Another Olympus E-M1 and SONY a7 walkabout test, high ISO

Started 11 months ago | Discussions
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: Thanks for admitting it finally.
In reply to Lab D, 11 months ago

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

skyglider wrote:

blue_skies wrote:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

Hi Henry,

I understand how the Oly 12-40mm is equivalent to 24-80mm in 35mm terms because of the 2x crop factor of the micro 4/3 sensor. But AFAIK, the aperture remains the same.

Aperture is the same.

Think of it this way:

A fat lady and a thin supermodel are laying on the beach. Who will get sun burnt faster? Answer: both will burn/tan the same despite the fat lady having 4x the skin area. This is because they both have the same exposure. Anyway, Four Thirds is the hot supermodel.

F/2.8 is the same for a Nikon 1, an RX100, the E-M1 and the A7.

f/2.8 = f/2.8 = f/2.8 across formats - same exposure. WE AGREE. You see? BUT THE NOISE LEVELS ARE NOT THE SAME.

Yes, and you know noise levels are NOT 2 stops different and dynamic range is NOT 2 stops different for these cameras. Dynamic range is about 1/2 stop for the majority of ISOs DxO tested.

http://www.dxomark.com

-- hide signature --

Cheers,
Henry

Here is what you link shows. As we agree, from ISO150 to ISO10000 (the most common range), there is maybe 1/2 stop. Interestingly, I didn't see before that sometimes it is only one third.

Thanks for this, and thanks for admitting the truth. If you adjust for the difference in the F/2.8 and F/4 lenses, we can see which the better camera is.

?????

Please go take ISO 6400 pictures with your EM1 then

You conveniently deleted that I stated that it is immaterial whether it is 2x, or 1.65x, or 1.5x stops. It is immaterial, imho, as I would not use a smaller sensor camera at higher ISO. Why not? Because the image quality degrades too much. I would rather use longer exposure and lower ISO, if possible.

And we have had this discussion so many times already. Why the nitpicking?

Lower the ISO, and both cameras are great. They both have their pros and cons.

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: Right.
In reply to Lab D, 11 months ago

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

Thanks for the samples, they are very helpful.

I would remind everyone that Olympus has wider aperture lenses and IBIS too. This means if you use the Olympus 12-40mm F/2.8 as a walkabout lens, not only will you have a greater range and more uses (also a great close-up lens), but you will get 1 extra stop of light over the new Sony 24-70mm F/4 lens.

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

You can expose on the Oly one stop faster (at f/2.8), but the sensor difference nullify this.

I saw in another thread where you admitted the difference between the E-M1 and A7 is NOT 2 stops, and when I went to DxO's site to verify this I saw the difference in noise was usualy about one to one and a half stops and the difference in dynamic range was almost always only 1/2 stop and maybe less. Are you now saying DxO is wrong? I'll take the camera with more dynamic range that can has a focus system that works over one that is very unreliable, had slightly less noise, but also less dynamcic range. I am just glad I can use the E-M1 to take pictures of kids in action with a lens over 70mm.

You throw in DR and other variables to get nitpicking on what is going on here. Please also start talking true ISO and true resolution and RAW vs RAW...

You never let facts get in the way do you. DxO normalizes for ISO (makes sure it is the same for cameras tested) and only compares RAW files because JPEGs are modified and can be misleading. So when they comapre apples to apples, the difference in dynamic range is about 1/2 stop and the difference in noise is much less than 2 stops, and you know this.

I didn't say F/2.8 is equal to F/4 either. You said that to distract eveyone.

ok, I repeat your first post:

Lab D wrote:

Thanks for the samples, they are very helpful.

I would remind everyone that Olympus has wider aperture lenses and IBIS too. This means if you use the Olympus 12-40mm F/2.8 as a walkabout lens, not only will you have a greater range and more uses (also a great close-up lens), but you will get 1 extra stop of light over the new Sony 24-70mm F/4 lens.

and I repeat my answer again:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

You can expose on the Oly one stop faster (at f/2.8), but the sensor difference nullify this.

I read, again, that you claim that the Oly 12-40/f2.8 gets you one stop faster than the Sony 24-70/f4.0.

Correct. Let's look at the picture from your link. Since the F/2.8 lens gets you an extra stop, you can shift the E-M1 results 1 stop (ISO) to the right. When you do that, it gives you more dynamic range than the A7 or A7R. Anyone claiming there is a 2 stop difference for those ISOs is not telling the truth.

?????

Please go take ISO 6400 pictures with your EM1 then

You conveniently deleted that I stated that it is immaterial whether it is 2x, or 1.65x, or 1.5x stops. It is immaterial, imho, as I would not use a smaller sensor camera at higher ISO. Why not? Because the image quality degrades too much. I would rather use longer exposure and lower ISO, if possible.

And we have had this discussion so many times already. Why the nitpicking?

Lower the ISO, and both cameras are great. They both have their pros and cons.

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: @ Lab D
In reply to Lab D, 11 months ago

Lab D wrote:

Thanks for the samples, they are very helpful.

I would remind everyone that Olympus has wider aperture lenses and IBIS too. This means if you use the Olympus 12-40mm F/2.8 as a walkabout lens, not only will you have a greater range and more uses (also a great close-up lens), but you will get 1 extra stop of light over the new Sony 24-70mm F/4 lens.

And if you are using primes, the FE primes don't have IS, so the IBIS will in some cases also give you a couple extra stops advantage.

For me it doesn't matter. There are no avaialbe long lenses fo rthe A7 and the focusing is still not good. For me the Sony is not even a consideration because it can't do what I want.

Since you are having a hard time to grasp the concept, why don't you consider the Sony (yes Sony) RX10 camera?

It has a constant f/2.8 aperture zoom lens, which has an FF-equivalent reach from 24mm-200mm in FF equivalent terms.

Per your own reasoning (see your dozen or so posts in the last two hour in two threads), this has a faster aperture than the A7 with the FE24-70/f4.0 and is exactly as fast as the EM1 with the 12-40/f2.8 (24-80mm in FF).

It is a perfect walk-about go-anywhere lens. Just a fixed one. But, per your comments, it is (obviously) the better choice And I mean the RX10

My point, that sensor size get into play, means that the EM1 is f/5.6 equivalent, and the RX10 is f/8.0 equivalent (see DPreviews preview link and image below). See the image below: in FF equivalency, the A7 sits at f/4 with the 24-70 zoom, the EM1 at f/5.6 and the RX10 at f/8.

But since f/4 versus f/5.6 does not matter, neither should f/5.6 versus f/8, right?

The RX10 cost less than half the EM1+12-40/2.8 and it easily outdoes it, per your arguments, correct?

If not, the difference between the RX10 and the EM1 (2x) is actually LESS than the difference between the EM1 and the A7 (4x), so per your own reasoning the RX10 is a MUCH BETTER camera than the EM1.

I mean, the EM1 becomes the fat lady and the RX10 the skinny one, and both get a sun-burn, right?

Ok, the RX10 has a fixed lens, but what else do you need, outside 24-200mm FF equivalent?

To make sure that you do not mis-quote me, sensor size matters. You seem to have a really hard time grasping how and why.

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
Daniel Wee
Contributing MemberPosts: 529Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to assaft, 11 months ago

Ahh.... darn. I forgot to mention that for that last shot I was using the Carl Zeiss 35mm F2.8 and the Olympus 17mm F1.8 lenses. Duh. How could I forget.

Apart from that, I would think that some of that blurriness could be due to the a7 misfocussing (it was on AF) or some form of shake. If I can, I'll try to do the same test again tonight under more controlled conditions. Sorry about the oversight.

 Daniel Wee's gear list:Daniel Wee's gear list
Canon PowerShot SD750 Olympus C-2000 Zoom Nikon D70 Panasonic Lumix DMC-GF1 Olympus E-M1 +17 more
Reply   Reply with quote   Complain
Lab D
Senior MemberPosts: 5,734Gear list
Like?
You missed it.
In reply to blue_skies, 11 months ago

blue_skies wrote:

Lab D wrote:

Thanks for the samples, they are very helpful.

I would remind everyone that Olympus has wider aperture lenses and IBIS too. This means if you use the Olympus 12-40mm F/2.8 as a walkabout lens, not only will you have a greater range and more uses (also a great close-up lens), but you will get 1 extra stop of light over the new Sony 24-70mm F/4 lens.

And if you are using primes, the FE primes don't have IS, so the IBIS will in some cases also give you a couple extra stops advantage.

For me it doesn't matter. There are no avaialbe long lenses fo rthe A7 and the focusing is still not good. For me the Sony is not even a consideration because it can't do what I want.

Since you are having a hard time to grasp the concept, why don't you consider the Sony (yes Sony) RX10 camera?

It has a constant f/2.8 aperture zoom lens, which has an FF-equivalent reach from 24mm-200mm in FF equivalent terms.

The RX10 is great camera. It also is an good example of what I said (glad to see you are agreeing with me again). Smaller sensors outperform larger sensor when you account for the size difference. For example, you would expect the A7 to be 2.7 stops better than the RX10, but is not (see diagram). It is only about 1.5 stops better, so if you use lenses that account for the 2.7 stop difference, the RX10 comes out ahead by a full stop as some ISOs. In fact, the RX10 with it's F/2.8 lens will beat the A7 F/5.6 zoom at 70mm and at some ISOs. Since there is no A7 lens that is longer than 70mm today, the RX10 is the best option for someone needing 100-200mm.

I loved my RX100, but the fixed lens made it too restrictive. I would get the RX10, but the size is a deterrent for me. I can put my GM1 in almost any pocket and I can attach a 300mm lens when I need it. Still, I highly recommend those Sony cameras.

I am done side tracking this thread, sorry Dan.

 Lab D's gear list:Lab D's gear list
Panasonic Lumix DMC-FZ1000 Nikon D600 Panasonic Lumix DMC-GH4
Reply   Reply with quote   Complain
Daniel Wee
Contributing MemberPosts: 529Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to blue_skies, 11 months ago

Thanks for your thoughtful reply. I agree with pretty much all you said - there were quite a few areas that I could have done better. I used the default sharpening in LR for the post-processing. Unfortunately I didn't have time to optimize them - I thought keeping them default would at least let us know where we can go from there.
As for the framing - it was quite difficult to get exact framing, given the slightly different aspect ratios, and the slightly longer reach of the 55mm. I moved just enough to roughly get things into the frame so that there would not be too much of a size disparity when looked at side by side.
On the image with the yellow wavy bits - the focus was set on the front most yellow board, on the top edge. As for the "horses", I used AF on both and it sure looks to me like there was some misfocus. If I could I would re-do this one as it is quite a useful photo with lots of detail. In the Cityscape photo, I forgot to mention that I switched to the CZ 35mm F2.8 and the Oly 17mm F1.8 for that shot. There too, it appears that there might be less than perfect focus on the a7 photo. I would re-do this one if possible.
Once again, thanks for your very useful remarks, both here and in the other thread.

 Daniel Wee's gear list:Daniel Wee's gear list
Canon PowerShot SD750 Olympus C-2000 Zoom Nikon D70 Panasonic Lumix DMC-GF1 Olympus E-M1 +17 more
Reply   Reply with quote   Complain
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: Lol, YOU missed it...
In reply to Lab D, 11 months ago

Lab D wrote:

blue_skies wrote:

Lab D wrote:

Thanks for the samples, they are very helpful.

I would remind everyone that Olympus has wider aperture lenses and IBIS too. This means if you use the Olympus 12-40mm F/2.8 as a walkabout lens, not only will you have a greater range and more uses (also a great close-up lens), but you will get 1 extra stop of light over the new Sony 24-70mm F/4 lens.

And if you are using primes, the FE primes don't have IS, so the IBIS will in some cases also give you a couple extra stops advantage.

For me it doesn't matter. There are no avaialbe long lenses fo rthe A7 and the focusing is still not good. For me the Sony is not even a consideration because it can't do what I want.

Since you are having a hard time to grasp the concept, why don't you consider the Sony (yes Sony) RX10 camera?

It has a constant f/2.8 aperture zoom lens, which has an FF-equivalent reach from 24mm-200mm in FF equivalent terms.

The RX10 is great camera. It also is an good example of what I said (glad to see you are agreeing with me again). Smaller sensors outperform larger sensor when you account for the size difference. For example, you would expect the A7 to be 2.7 stops better than the RX10, but is not (see diagram). It is only about 1.5 stops better, so if you use lenses that account for the 2.7 stop difference, the RX10 comes out ahead by a full stop as some ISOs. In fact, the RX10 with it's F/2.8 lens will beat the A7 F/5.6 zoom at 70mm and at some ISOs. Since there is no A7 lens that is longer than 70mm today, the RX10 is the best option for someone needing 100-200mm.

I loved my RX100, but the fixed lens made it too restrictive. I would get the RX10, but the size is a deterrent for me. I can put my GM1 in almost any pocket and I can attach a 300mm lens when I need it. Still, I highly recommend those Sony cameras.

I am done side tracking this thread, sorry Dan.

You keep nibbling on whether the "better" is quantified at 2x, 1.65x or 1.5x (see how early on I mentioned this?).

My point is that it is qualitatively better. The exact number is irrelevant, to a large degree.

I don't want to nitpick the graphs, they are what they are. Your understanding of them needs a little bit of work. Take some pictures, for starters.

If you can shoot low ISO - a smaller sensor is easier to work with if you can tolerate large DOF.

But if you shoot at high ISO - a larger sensor is your friend.

FWIW, you seem to not be able to understand that.

And by the way - your meandering by twisting subjects and attacking the messenger(s) does not change what was being discussed here: a 24Mp FF camera is a better choice at high(er) ISO levels than a 16Mp m43 camera. Pictures don't lie, especially the ones posted.

So go and enjoy your RX100??? (You actually purchased a Sony camera, lol?)

None of your side-discussions have any bearing on the main point: sensor size matters. For if it did not, we'd all be shooting with cell phone cameras, wouldn't we?

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
TheEyesHaveIt
Forum MemberPosts: 86Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to Daniel Wee, 11 months ago

Thanks for posting the comparison images. I think it is pretty apparent how these formats differ, especially in terms of DOF, IQ, and detail.

 TheEyesHaveIt's gear list:TheEyesHaveIt's gear list
Sony RX100 Sony Alpha NEX-6 Nikon D5300 Sony E 10-18mm F4 OSS Sony E 35mm F1.8 OSS +1 more
Reply   Reply with quote   Complain
brycesteiner
Senior MemberPosts: 1,354Gear list
Like?
Nice
In reply to Daniel Wee, 11 months ago

You make very good comparisons for what you had to work with in public.

There are two shots where the noise looks better on the E-M1 to me. Otherwise the noise is better on the Sony. The EM-1, against logic, seems to have more detail in a couple of the pictures.

I do agree with the colors on the OMD series. The reds are too saturated and become "orange", losing detail. Since I shoot JPG I set the saturation -1 and the same for sharpness. I try to leave the camera on a specific white balance (depending on the light) then if I need to I change the whole group in Aperture. Though Oly's WB is pretty good, some lights just throw it off with their flicker of different colors.

Output on both cameras look like winners.

-- hide signature --

Make it a Great day!

 brycesteiner's gear list:brycesteiner's gear list
Olympus E-510 Olympus E-30 Olympus OM-D E-M5 Olympus Zuiko Digital ED 9-18mm 1:4.0-5.6 Olympus Zuiko Digital ED 14-42mm 1:3.5-5.6 +5 more
Reply   Reply with quote   Complain
technic
Veteran MemberPosts: 8,626Gear list
Like?
Re: can't choose on IQ anymore
In reply to ohmydentist, 11 months ago

ohmydentist wrote:

Choosing camera based on IQ is like choosing a car based on whether it could take you from point A to B. All cars do it very very and very well.

Optics, AF performance (accuracy, speed) and IS can be more important nowadays for image quality than the sensor, assuming one chooses between the better mirrorless and DSLR cameras (also depending on the type of photography of course). Choosing a camera is also choosing a lens line which can make a major difference for IQ and creative options, especially if you want full functionality like auto-aperture, good AF, IS etc.

 technic's gear list:technic's gear list
Canon EOS 450D Canon EF 50mm f/1.8 II Canon EF 200mm f/2.8L II USM Canon EF 300mm f/4.0L IS USM Canon EF-S 15-85mm f/3.5-5.6 IS USM +5 more
Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 19,048Gear list
Like?
Re: Thanks for the truth!
In reply to blue_skies, 11 months ago

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

skyglider wrote:

blue_skies wrote:

skyglider wrote:

blue_skies wrote:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

Hi Henry,

I understand how the Oly 12-40mm is equivalent to 24-80mm in 35mm terms because of the 2x crop factor of the micro 4/3 sensor. But AFAIK, the aperture remains the same.

IOW, if an Oly 12mm lens could be used on a full frame (35mm) sensor, only the center 1/4 of the sensor area would be illuminated which is equivalent to 1/2 the horizontal and vertical pixels. Thus the crop factor of 2x. But the aperture remains the same so the same amount of light is hitting that portion of the sensor by the F2.8 aperture. So the aperture does "not" become equivalent to a F5.6 aperture.

Is my understanding incorrect?

Thanks,
Sky

Hi Sky, no your understanding is correct.

In terms of ISO, aperture and shutter speed, the exposure is the SAME on the small and the larger sensor.

If you are after (fast) shutter speed, you only care about the lens speed, and your thinking is correct.

But in terms of noise, the larger sensor allows to operate at a much higher ISO level and produce the same amount of noise: in m43/FF this is a 4x ratio, or 2 stops. This means that eg. m43 at ISO 1,000 is as noise as FF at ISO 4,000.

So, if you want to produce comparable images, you would shoot the FF image with two stops slower aperture and at two stops higher ISO. This is equivalent exposure.

Ironically, the same metric applies to DOF - you roughly see about the same DOF in both images as well.

Thus, shooting the Oly at 12mm f/2.8, ISO 1,000 as 1/60th is equivalent to shooting the Sony at f/5.6, ISO 4,000 and 1/60th. Aside from the resolution, the two images will appear similar.

If you use the same exposure on both, you are comparing the FF at ISO 1,000 versus the Oly at ISO 1,000. The FF image will have a lot less noise, ie. be much cleaner, but the DOF will also be reduced. The images are not equivalent at that point.

On FF you can trade noise for DOF, assuming you have a fast lens. There is a 2 stop delta to play with.

In the example, using the Sony lens at f/4.0 implies that the ISO goes to 2,000. This is one stop below the equivalent values of f/5.6 and ISO 4,000, so, with more shallow DOF, you will have a less noisy image on the FF.

-- hide signature --

Cheers,
Henry

Hi Henry,

I think I understand your point now. I wondered how many stops difference there was between a micro 4/3 sensor verses a full frame sensor. Now I know it's a 4x ratio or 2 stops difference.

That only applies for Depth of field. If you check the results from DxO tests, the difference is much less. A good example is dynamic range where the E-M1 is only about 1/2 stop different than the A7 for most of the ISO settings DxO tested.

Remember if you need F/2.8, 1/60th sec shutter speed, and ISO800 on the E-M1, you will need the SAME settings on an A7, a Nikon 1 and a Sony RX100. It would even be the same on your smartphone!

Again, exposure = exposure and equivalence = equivalence.

And you know in this case equivalance does not tell us the facts. Admit it, there is NOT a 2 stop difference for noise or dynamic range at almsot all the ISOs DxO tested.

Just admit the truth for once.

Henry showing the difference between sensors

-- hide signature --

Cheers,
Henry

You are right with the DxO link. The difference is really negligible. There is not a 2 stop difference almost all of time here.

?????

Please go take ISO 6400 pictures with your EM1 then

You conveniently deleted that I stated that it is immaterial whether it is 2x, or 1.65x, or 1.5x stops.

Where did you state that? And of course it isn't immaterial. If it's less than two stops (as it certainly is), MFT has an advantage with regard to signal-noise performance for equivalent images (same DoF, same shutter speed, different exposure, different ISOs).

It is immaterial, imho, as I would not use a smaller sensor camera at higher ISO. Why not? Because the image quality degrades too much. I would rather use longer exposure and lower ISO, if possible.

When you are in a position to freely increase the length of the exposure (because the scene is static), you are also free to bracket exposure and merge/align multiple images. This makes sensor performance a moot point.

When you are not in a position to do so, MFT has the advantage with regard to signal-noise performance for equivalent images.

And we have had this discussion so many times already. Why the nitpicking?

Because you are not admitting the truth.

Lower the ISO, and both cameras are great. They both have their pros and cons.

They both have their pros and cons, but it is important to be factually correct about what those pros and cons are.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
Daniel Wee
Contributing MemberPosts: 529Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to photofan1986, 11 months ago

Okay, I went and re-did the Cityscape photos because I didn't think the Carl Zeiss 35mm F2.8 would be that bad. Here's the new test. This time round, I shot at ISO3200, ISO1600, and ISO100. For the E-M1 shots, I also did some at F8 although I think the F4 shots should match the F8 on the Carl Zeiss for depth-of-field. So to satisfy everyone, I have got the F4 and F8 versions for the ISO3200 and ISO100 shots for the E-M1/17mm.

Since the 17mm gives you the field of view of a 34mm lens on FF, you will notices some field of view differences between that (wider) and the 35mm of the Carl Zeiss.

On Lightroom 5.3, this time I've used pretty much the same settings for both the ARW and ORF RAW files. Because the E-M1 has a tendency to expose for the shadows apparently, it tended to result in some blown-out highlights. As a result, I had to turn the highlights down a bit more to recover some details. As far as I am concerned, this is all fair game since these are the tools available to me.

Okay, so without much ado, here goes:-

a7 ISO 3200, 0.8 sec @ F8

E-M1 ISO 3200, 1/2 sec @F4

E-M1 ISO 3200, 1.6 sec @F8

a7 ISO 1600, 1.6 sec @F8

E-M1 ISO 1600, 0.8 sec @F4

a7 ISO 100, 30 sec @F8

E-M1 ISO 100, 13 sec @F4

E-M1 ISO 100, 50 sec @F8

The first thing that we can see is that my earlier Cityscape test image for the Carl Zeiss was indeed misfocussed. This set shows that it is very sharp from edge to edge, and is easily comparable to the Olympus 17mm lens, which speaks well for both of them.
I should also add that I have little interest in technical comparisons. I'm only looking at how an end user might use the cameras to get a particular shot, and personally - my specific interest is high-ISO performance and depth-of-field. Therefore, this is not necessarily a "fair" comparison from a scientific point of view, but I would think it is fair enough from an end-user's point of view.

 Daniel Wee's gear list:Daniel Wee's gear list
Canon PowerShot SD750 Olympus C-2000 Zoom Nikon D70 Panasonic Lumix DMC-GF1 Olympus E-M1 +17 more
Reply   Reply with quote   Complain
amalric
Forum ProPosts: 10,815
Like?
Re: You are rigtht and BS is try to sell Sonys
In reply to Lab D, 11 months ago

Lab D wrote:

skyglider wrote:

blue_skies wrote:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

Hi Henry,

I understand how the Oly 12-40mm is equivalent to 24-80mm in 35mm terms because of the 2x crop factor of the micro 4/3 sensor. But AFAIK, the aperture remains the same.

Aperture is the same.

Think of it this way:

A fat lady and a thin supermodel are laying on the beach. Who will get sun burnt faster? Answer: both will burn/tan the same despite the fat lady having 4x the skin area. This is because they both have the same exposure. Anyway, Four Thirds is the hot supermodel.

F/2.8 is the same for a Nikon 1, an RX100, the E-M1 and the A7.

LOL, this is the best I have ever read about exposure. You made my day, and I am sure to quote it. Thank you

Am.

Reply   Reply with quote   Complain
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: Thanks for the truth!
In reply to Anders W, 11 months ago

Anders W wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

skyglider wrote:

blue_skies wrote:

skyglider wrote:

blue_skies wrote:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

Hi Henry,

I understand how the Oly 12-40mm is equivalent to 24-80mm in 35mm terms because of the 2x crop factor of the micro 4/3 sensor. But AFAIK, the aperture remains the same.

IOW, if an Oly 12mm lens could be used on a full frame (35mm) sensor, only the center 1/4 of the sensor area would be illuminated which is equivalent to 1/2 the horizontal and vertical pixels. Thus the crop factor of 2x. But the aperture remains the same so the same amount of light is hitting that portion of the sensor by the F2.8 aperture. So the aperture does "not" become equivalent to a F5.6 aperture.

Is my understanding incorrect?

Thanks,
Sky

Hi Sky, no your understanding is correct.

In terms of ISO, aperture and shutter speed, the exposure is the SAME on the small and the larger sensor.

If you are after (fast) shutter speed, you only care about the lens speed, and your thinking is correct.

But in terms of noise, the larger sensor allows to operate at a much higher ISO level and produce the same amount of noise: in m43/FF this is a 4x ratio, or 2 stops. This means that eg. m43 at ISO 1,000 is as noise as FF at ISO 4,000.

So, if you want to produce comparable images, you would shoot the FF image with two stops slower aperture and at two stops higher ISO. This is equivalent exposure.

Ironically, the same metric applies to DOF - you roughly see about the same DOF in both images as well.

Thus, shooting the Oly at 12mm f/2.8, ISO 1,000 as 1/60th is equivalent to shooting the Sony at f/5.6, ISO 4,000 and 1/60th. Aside from the resolution, the two images will appear similar.

If you use the same exposure on both, you are comparing the FF at ISO 1,000 versus the Oly at ISO 1,000. The FF image will have a lot less noise, ie. be much cleaner, but the DOF will also be reduced. The images are not equivalent at that point.

On FF you can trade noise for DOF, assuming you have a fast lens. There is a 2 stop delta to play with.

In the example, using the Sony lens at f/4.0 implies that the ISO goes to 2,000. This is one stop below the equivalent values of f/5.6 and ISO 4,000, so, with more shallow DOF, you will have a less noisy image on the FF.

-- hide signature --

Cheers,
Henry

Hi Henry,

I think I understand your point now. I wondered how many stops difference there was between a micro 4/3 sensor verses a full frame sensor. Now I know it's a 4x ratio or 2 stops difference.

That only applies for Depth of field. If you check the results from DxO tests, the difference is much less. A good example is dynamic range where the E-M1 is only about 1/2 stop different than the A7 for most of the ISO settings DxO tested.

Remember if you need F/2.8, 1/60th sec shutter speed, and ISO800 on the E-M1, you will need the SAME settings on an A7, a Nikon 1 and a Sony RX100. It would even be the same on your smartphone!

Again, exposure = exposure and equivalence = equivalence.

And you know in this case equivalance does not tell us the facts. Admit it, there is NOT a 2 stop difference for noise or dynamic range at almsot all the ISOs DxO tested.

Just admit the truth for once.

Henry showing the difference between sensors

-- hide signature --

Cheers,
Henry

You are right with the DxO link. The difference is really negligible. There is not a 2 stop difference almost all of time here.

?????

Please go take ISO 6400 pictures with your EM1 then

You conveniently deleted that I stated that it is immaterial whether it is 2x, or 1.65x, or 1.5x stops.

Where did you state that? And of course it isn't immaterial. If it's less than two stops (as it certainly is), MFT has an advantage with regard to signal-noise performance for equivalent images (same DoF, same shutter speed, different exposure, different ISOs).

http://www.dpreview.com/forums/post/53010416

"If DxO points out that it is 1.65x stops or 1.5x stops, it does NOT CHANGE the general thoughts"

Sure, MFT has a 'technical advantage' but the image is worse - my eyes don't deceive me - download Daniel's newly uploaded full-image side-by-side and see for yourself.

@ ISO 3200 - M1 at left, A7 at right

@ ISO 100 - M1 at left, A7 at right

It is immaterial, imho, as I would not use a smaller sensor camera at higher ISO. Why not? Because the image quality degrades too much. I would rather use longer exposure and lower ISO, if possible.

When you are in a position to freely increase the length of the exposure (because the scene is static), you are also free to bracket exposure and merge/align multiple images. This makes sensor performance a moot point.

When you are not in a position to do so, MFT has the advantage with regard to signal-noise performance for equivalent images.

See the image above, sure, it can be improved upon, but as Daniel said "the way a user would do it". Clearly the images are not similar in IQ, neither at ISO 100 nor at ISO 3200.

And we have had this discussion so many times already. Why the nitpicking?

Because you are not admitting the truth.

What truth? I thank Daniel for uploading the images - they speak for themselves.

Technical slides do not tell this story, and in the analysis we get lost in sensor efficiency, not image IQ.

Lower the ISO, and both cameras are great. They both have their pros and cons.

They both have their pros and cons, but it is important to be factually correct about what those pros and cons are.

See my comments here: http://www.dpreview.com/forums/post/53009228

Pros and cons are subject to an individual bias.

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to Daniel Wee, 11 months ago

Daniel Wee wrote:

Okay, I went and re-did the Cityscape photos because I didn't think the Carl Zeiss 35mm F2.8 would be that bad. Here's the new test. This time round, I shot at ISO3200, ISO1600, and ISO100. For the E-M1 shots, I also did some at F8 although I think the F4 shots should match the F8 on the Carl Zeiss for depth-of-field. So to satisfy everyone, I have got the F4 and F8 versions for the ISO3200 and ISO100 shots for the E-M1/17mm.

Since the 17mm gives you the field of view of a 34mm lens on FF, you will notices some field of view differences between that (wider) and the 35mm of the Carl Zeiss.

On Lightroom 5.3, this time I've used pretty much the same settings for both the ARW and ORF RAW files. Because the E-M1 has a tendency to expose for the shadows apparently, it tended to result in some blown-out highlights. As a result, I had to turn the highlights down a bit more to recover some details. As far as I am concerned, this is all fair game since these are the tools available to me.

Okay, so without much ado, here goes:-

a7 ISO 3200, 0.8 sec @ F8

E-M1 ISO 3200, 1/2 sec @F4

E-M1 ISO 3200, 1.6 sec @F8

a7 ISO 1600, 1.6 sec @F8

E-M1 ISO 1600, 0.8 sec @F4

a7 ISO 100, 30 sec @F8

E-M1 ISO 100, 13 sec @F4

E-M1 ISO 100, 50 sec @F8

The first thing that we can see is that my earlier Cityscape test image for the Carl Zeiss was indeed misfocussed. This set shows that it is very sharp from edge to edge, and is easily comparable to the Olympus 17mm lens, which speaks well for both of them.
I should also add that I have little interest in technical comparisons. I'm only looking at how an end user might use the cameras to get a particular shot, and personally - my specific interest is high-ISO performance and depth-of-field. Therefore, this is not necessarily a "fair" comparison from a scientific point of view, but I would think it is fair enough from an end-user's point of view.

Thanks for doing this, Daniel, below the side-by-sides:

@ ISO 3200 - M1 at left, A7 at right

@ ISO 100 - M1 at left, A7 at right

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
Caledonia
Forum MemberPosts: 75Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to quezra, 11 months ago

I noticed that too, and suspect that particular E-M1 frame is a candidate for a re-do, if it were possible.  It's quite singular, and the IQ is completely inconsistent with the rest of the series.  Murphy at work, I suspect.

I appreciate the series and the trouble it took to prepare it.

Reply   Reply with quote   Complain
Anders W
Forum ProPosts: 19,048Gear list
Like?
Re: Thanks for the truth!
In reply to blue_skies, 11 months ago

blue_skies wrote:

Anders W wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

skyglider wrote:

blue_skies wrote:

skyglider wrote:

blue_skies wrote:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

Hi Henry,

I understand how the Oly 12-40mm is equivalent to 24-80mm in 35mm terms because of the 2x crop factor of the micro 4/3 sensor. But AFAIK, the aperture remains the same.

IOW, if an Oly 12mm lens could be used on a full frame (35mm) sensor, only the center 1/4 of the sensor area would be illuminated which is equivalent to 1/2 the horizontal and vertical pixels. Thus the crop factor of 2x. But the aperture remains the same so the same amount of light is hitting that portion of the sensor by the F2.8 aperture. So the aperture does "not" become equivalent to a F5.6 aperture.

Is my understanding incorrect?

Thanks,
Sky

Hi Sky, no your understanding is correct.

In terms of ISO, aperture and shutter speed, the exposure is the SAME on the small and the larger sensor.

If you are after (fast) shutter speed, you only care about the lens speed, and your thinking is correct.

But in terms of noise, the larger sensor allows to operate at a much higher ISO level and produce the same amount of noise: in m43/FF this is a 4x ratio, or 2 stops. This means that eg. m43 at ISO 1,000 is as noise as FF at ISO 4,000.

So, if you want to produce comparable images, you would shoot the FF image with two stops slower aperture and at two stops higher ISO. This is equivalent exposure.

Ironically, the same metric applies to DOF - you roughly see about the same DOF in both images as well.

Thus, shooting the Oly at 12mm f/2.8, ISO 1,000 as 1/60th is equivalent to shooting the Sony at f/5.6, ISO 4,000 and 1/60th. Aside from the resolution, the two images will appear similar.

If you use the same exposure on both, you are comparing the FF at ISO 1,000 versus the Oly at ISO 1,000. The FF image will have a lot less noise, ie. be much cleaner, but the DOF will also be reduced. The images are not equivalent at that point.

On FF you can trade noise for DOF, assuming you have a fast lens. There is a 2 stop delta to play with.

In the example, using the Sony lens at f/4.0 implies that the ISO goes to 2,000. This is one stop below the equivalent values of f/5.6 and ISO 4,000, so, with more shallow DOF, you will have a less noisy image on the FF.

-- hide signature --

Cheers,
Henry

Hi Henry,

I think I understand your point now. I wondered how many stops difference there was between a micro 4/3 sensor verses a full frame sensor. Now I know it's a 4x ratio or 2 stops difference.

That only applies for Depth of field. If you check the results from DxO tests, the difference is much less. A good example is dynamic range where the E-M1 is only about 1/2 stop different than the A7 for most of the ISO settings DxO tested.

Remember if you need F/2.8, 1/60th sec shutter speed, and ISO800 on the E-M1, you will need the SAME settings on an A7, a Nikon 1 and a Sony RX100. It would even be the same on your smartphone!

Again, exposure = exposure and equivalence = equivalence.

And you know in this case equivalance does not tell us the facts. Admit it, there is NOT a 2 stop difference for noise or dynamic range at almsot all the ISOs DxO tested.

Just admit the truth for once.

Henry showing the difference between sensors

-- hide signature --

Cheers,
Henry

You are right with the DxO link. The difference is really negligible. There is not a 2 stop difference almost all of time here.

?????

Please go take ISO 6400 pictures with your EM1 then

You conveniently deleted that I stated that it is immaterial whether it is 2x, or 1.65x, or 1.5x stops.

Where did you state that? And of course it isn't immaterial. If it's less than two stops (as it certainly is), MFT has an advantage with regard to signal-noise performance for equivalent images (same DoF, same shutter speed, different exposure, different ISOs).

http://www.dpreview.com/forums/post/53010416

"If DxO points out that it is 1.65x stops or 1.5x stops, it does NOT CHANGE the general thoughts"

It certainly does. The facts are as follows:

1. With respect to exposure, that is, the amount of light falling on the sensor per area unit (e.g., per square millimeter), f/2.8 on MFT is equivalent to f/2.8 on FF.

2. With respect to the total amount of light falling on the sensor, DoF, and diffraction, f/2.8 on MFT is equivalent to f/5.6 on FF (assuming, with regard to DoF, that the AoV and the focus distance is the same).

3. The total amount of light falling on the sensor is not the only determinant of signal-noise performance. What additionally matters is the quantum efficiency and the read-noise performance. In these regards, smaller sensors tend to be more efficient than larger sensors, as illustrated, for example by the graph posted by Lab D. Consequently, the difference between the A7/A7R and the E-M1 with regard to signal-noise performance at the same exposure is less than two stops.

You consistently overlook point 3 in spite of the fact that it has repeatedly been pointed out to you for months.

Sure, MFT has a 'technical advantage' but the image is worse - my eyes don't deceive me - download Daniel's newly uploaded full-image side-by-side and see for yourself.

Your eyes may not deceive you but your brain certainly does. Daniel's images are not equivalent images (see definition above). Rather they are images shot at the same exposure, in which case the A7 can be expected to do better with regard to signal-noise performance (although less than two stops better) but at the expense of two stops less worth of DoF.

It is immaterial, imho, as I would not use a smaller sensor camera at higher ISO. Why not? Because the image quality degrades too much. I would rather use longer exposure and lower ISO, if possible.

When you are in a position to freely increase the length of the exposure (because the scene is static), you are also free to bracket exposure and merge/align multiple images. This makes sensor performance a moot point.

When you are not in a position to do so, MFT has the advantage with regard to signal-noise performance for equivalent images.

See the image above, sure, it can be improved upon, but as Daniel said "the way a user would do it". Clearly the images are not similar in IQ, neither at ISO 100 nor at ISO 3200.

Again, the images above are not equivalent.

And we have had this discussion so many times already. Why the nitpicking?

Because you are not admitting the truth.

What truth?

The truth contained in my point 3 above.

I thank Daniel for uploading the images - they speak for themselves.

Only if you know how to interpret them correctly and you just showed you didn't.

Technical slides do not tell this story, and in the analysis we get lost in sensor efficiency, not image IQ.

"Technical slides" (I'd call them diagrams) do tell the story as long as they reflect relevant and accurate measurements (as they do in this case). And sensor efficiency has implications for image quality as indicated by my point 3 above.

Lower the ISO, and both cameras are great. They both have their pros and cons.

They both have their pros and cons, but it is important to be factually correct about what those pros and cons are.

See my comments here: http://www.dpreview.com/forums/post/53009228

Pros and cons are subject to an individual bias.

The facts are objective, the evaluation of those facts is not.

 Anders W's gear list:Anders W's gear list
Panasonic Lumix DMC-G1 Olympus OM-D E-M5 Olympus E-M1 Panasonic Lumix G Vario 14-45mm F3.5-5.6 ASPH OIS Panasonic Lumix G Vario 7-14mm F4 ASPH +21 more
Reply   Reply with quote   Complain
blue_skies
Senior MemberPosts: 7,467Gear list
Like?
Re: Thanks for the truth!
In reply to Anders W, 11 months ago

Anders W wrote:

blue_skies wrote:

Anders W wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

blue_skies wrote:

Lab D wrote:

skyglider wrote:

blue_skies wrote:

skyglider wrote:

blue_skies wrote:

How so: in equivalence terms, the Oly 12-40/f2.8 becomes 24-80/f5.6 versus the Sony 24-70/f4.0?

Hi Henry,

I understand how the Oly 12-40mm is equivalent to 24-80mm in 35mm terms because of the 2x crop factor of the micro 4/3 sensor. But AFAIK, the aperture remains the same.

IOW, if an Oly 12mm lens could be used on a full frame (35mm) sensor, only the center 1/4 of the sensor area would be illuminated which is equivalent to 1/2 the horizontal and vertical pixels. Thus the crop factor of 2x. But the aperture remains the same so the same amount of light is hitting that portion of the sensor by the F2.8 aperture. So the aperture does "not" become equivalent to a F5.6 aperture.

Is my understanding incorrect?

Thanks,
Sky

Hi Sky, no your understanding is correct.

In terms of ISO, aperture and shutter speed, the exposure is the SAME on the small and the larger sensor.

If you are after (fast) shutter speed, you only care about the lens speed, and your thinking is correct.

But in terms of noise, the larger sensor allows to operate at a much higher ISO level and produce the same amount of noise: in m43/FF this is a 4x ratio, or 2 stops. This means that eg. m43 at ISO 1,000 is as noise as FF at ISO 4,000.

So, if you want to produce comparable images, you would shoot the FF image with two stops slower aperture and at two stops higher ISO. This is equivalent exposure.

Ironically, the same metric applies to DOF - you roughly see about the same DOF in both images as well.

Thus, shooting the Oly at 12mm f/2.8, ISO 1,000 as 1/60th is equivalent to shooting the Sony at f/5.6, ISO 4,000 and 1/60th. Aside from the resolution, the two images will appear similar.

If you use the same exposure on both, you are comparing the FF at ISO 1,000 versus the Oly at ISO 1,000. The FF image will have a lot less noise, ie. be much cleaner, but the DOF will also be reduced. The images are not equivalent at that point.

On FF you can trade noise for DOF, assuming you have a fast lens. There is a 2 stop delta to play with.

In the example, using the Sony lens at f/4.0 implies that the ISO goes to 2,000. This is one stop below the equivalent values of f/5.6 and ISO 4,000, so, with more shallow DOF, you will have a less noisy image on the FF.

-- hide signature --

Cheers,
Henry

Hi Henry,

I think I understand your point now. I wondered how many stops difference there was between a micro 4/3 sensor verses a full frame sensor. Now I know it's a 4x ratio or 2 stops difference.

That only applies for Depth of field. If you check the results from DxO tests, the difference is much less. A good example is dynamic range where the E-M1 is only about 1/2 stop different than the A7 for most of the ISO settings DxO tested.

Remember if you need F/2.8, 1/60th sec shutter speed, and ISO800 on the E-M1, you will need the SAME settings on an A7, a Nikon 1 and a Sony RX100. It would even be the same on your smartphone!

Again, exposure = exposure and equivalence = equivalence.

And you know in this case equivalance does not tell us the facts. Admit it, there is NOT a 2 stop difference for noise or dynamic range at almsot all the ISOs DxO tested.

Just admit the truth for once.

Henry showing the difference between sensors

-- hide signature --

Cheers,
Henry

You are right with the DxO link. The difference is really negligible. There is not a 2 stop difference almost all of time here.

?????

Please go take ISO 6400 pictures with your EM1 then

You conveniently deleted that I stated that it is immaterial whether it is 2x, or 1.65x, or 1.5x stops.

Where did you state that? And of course it isn't immaterial. If it's less than two stops (as it certainly is), MFT has an advantage with regard to signal-noise performance for equivalent images (same DoF, same shutter speed, different exposure, different ISOs).

http://www.dpreview.com/forums/post/53010416

"If DxO points out that it is 1.65x stops or 1.5x stops, it does NOT CHANGE the general thoughts"

It certainly does. The facts are as follows:

1. With respect to exposure, that is, the amount of light falling on the sensor per area unit (e.g., per square millimeter), f/2.8 on MFT is equivalent to f/2.8 on FF.

2. With respect to the total amount of light falling on the sensor, DoF, and diffraction, f/2.8 on MFT is equivalent to f/5.6 on FF (assuming, with regard to DoF, that the AoV and the focus distance is the same).

3. The total amount of light falling on the sensor is not the only determinant of signal-noise performance. What additionally matters is the quantum efficiency and the read-noise performance. In these regards, smaller sensors tend to be more efficient than larger sensors, as illustrated, for example by the graph posted by Lab D. Consequently, the difference between the A7/A7R and the E-M1 with regard to signal-noise performance at the same exposure is less than two stops.

You consistently overlook point 3 in spite of the fact that it has repeatedly been pointed out to you for months.

Not at all Anders, you have elaborated on this in the past, and the difference, even per DxO, they rate the ISO performance for the cameras as EM1/A7/A7r as 757/2248/2746. Two stops would have been 3028. So we all agree?

Sure, MFT has a 'technical advantage' but the image is worse - my eyes don't deceive me - download Daniel's newly uploaded full-image side-by-side and see for yourself.

Your eyes may not deceive you but your brain certainly does. Daniel's images are not equivalent images (see definition above). Rather they are images shot at the same exposure, in which case the A7 can be expected to do better with regard to signal-noise performance (although less than two stops better) but at the expense of two stops less worth of DoF.

And this is my argument: users shoot alike Daniel, and this produces images that may or may not be equivalent - even in Daniel's case he tried to match FL, aperture and framing as best as he could. Yet the resulting images speak for themselves.

It is immaterial, imho, as I would not use a smaller sensor camera at higher ISO. Why not? Because the image quality degrades too much. I would rather use longer exposure and lower ISO, if possible.

When you are in a position to freely increase the length of the exposure (because the scene is static), you are also free to bracket exposure and merge/align multiple images. This makes sensor performance a moot point.

When you are not in a position to do so, MFT has the advantage with regard to signal-noise performance for equivalent images.

See the image above, sure, it can be improved upon, but as Daniel said "the way a user would do it". Clearly the images are not similar in IQ, neither at ISO 100 nor at ISO 3200.

Again, the images above are not equivalent.

They are not, and I expected the high ISO image to perform better on the larger sensor. Again, read noise and pixel noise are not the same, and the larger sensor has larger pixels.

But the low ISO image surprised me, I would have expected the ISO 100 images to be much closer to each other in IQ than they in fact are.

And we have had this discussion so many times already. Why the nitpicking?

Because you are not admitting the truth.

What truth?

The truth contained in my point 3 above.

Which shows that the ratio is not proportional to sensor size. It still confirms that larger sensors perform better. Let me explain: per your point, an 'equivalent' exposure on the smaller sensor would be of higher IQ. But the larger sensor allows more noise/DOF trade-off which results in a higher IQ image (but non-equivalent), at the cost of shallow DOF (which may or may not matter).

I thank Daniel for uploading the images - they speak for themselves.

Only if you know how to interpret them correctly and you just showed you didn't.

Which image would you hang on the wall then? Perhaps not equivalent, but one camera is cleanly cleaner.

Technical slides do not tell this story, and in the analysis we get lost in sensor efficiency, not image IQ.

"Technical slides" (I'd call them diagrams) do tell the story as long as they reflect relevant and accurate measurements (as they do in this case). And sensor efficiency has implications for image quality as indicated by my point 3 above.

Yes, and you repeat this as often as you can. But to my point - show side-by-side images, let them speak. We have side-by-side images here to point at, and I would definitely pick the larger sensor camera.

Change the venue and shoot people walking at low ISO, I would expect the smaller sensor camera to pull ahead.

Like I said, both cameras have pros and cons, but low light & high ISO (and shallow DOF) are not the smaller sensor's strong points.

Lower the ISO, and both cameras are great. They both have their pros and cons.

They both have their pros and cons, but it is important to be factually correct about what those pros and cons are.

See my comments here: http://www.dpreview.com/forums/post/53009228

Pros and cons are subject to an individual bias.

The facts are objective, the evaluation of those facts is not.

Then show us how to shoot the M1? Obviously, users don't know how to.

-- hide signature --

Cheers,
Henry

 blue_skies's gear list:blue_skies's gear list
Canon PowerShot S95 Sony Alpha NEX-7 Sony Alpha NEX-6 Sony Alpha 7 Sony a6000 +34 more
Reply   Reply with quote   Complain
Ulric
Senior MemberPosts: 2,629Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to Daniel Wee, 11 months ago

Daniel Wee wrote:

Okay, I went and re-did the Cityscape photos because I didn't think the Carl Zeiss 35mm F2.8 would be that bad. Here's the new test. This time round, I shot at ISO3200, ISO1600, and ISO100. For the E-M1 shots, I also did some at F8 although I think the F4 shots should match the F8 on the Carl Zeiss for depth-of-field. So to satisfy everyone, I have got the F4 and F8 versions for the ISO3200 and ISO100 shots for the E-M1/17mm.

These two happen to have received about the same amount of light:

a7 ISO 3200, 0.8 sec @ F8


E-M1 ISO 1600, 0.8 sec @F4

 Ulric's gear list:Ulric's gear list
Panasonic Lumix DMC-GF3 Olympus OM-D E-M5 Panasonic Lumix DMC-GM1 Panasonic Lumix G 20mm F1.7 ASPH Panasonic Lumix G 14mm F2.5 ASPH +6 more
Reply   Reply with quote   Complain
Ulric
Senior MemberPosts: 2,629Gear list
Like?
Re: Another Olympus E-M1 and SONY a7 walkabout test, high ISO
In reply to Ulric, 11 months ago

Ulric wrote:

These two happen to have received about the same amount of light:

a7 ISO 3200, 0.8 sec @ F8

E-M1 ISO 1600, 0.8 sec @F4

Crops:

 Ulric's gear list:Ulric's gear list
Panasonic Lumix DMC-GF3 Olympus OM-D E-M5 Panasonic Lumix DMC-GM1 Panasonic Lumix G 20mm F1.7 ASPH Panasonic Lumix G 14mm F2.5 ASPH +6 more
Reply   Reply with quote   Complain
Keyboard shortcuts:
FForum MMy threads