A quick day out with the Olympus E-M1 and the SONY a7

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Daniel Wee
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A quick day out with the Olympus E-M1 and the SONY a7
6 months ago

I had some time today and wanted to see how the E-M1 and the a7 compares in real world usage. As I only have the Carl Zeiss 35mm F2.8 on hand, I decided to use the Olympus 17mm F1.8 as a way to bring the match closer. I am aware that as far as depth of field is concerned, the Olympus translates to F3.6 in 35mm terms. Be that as it may, that was the fastest 17mm lens we can readily get so that's what I tested.

Right off the bat, let me just say that both cameras and lenses are mine so I have no vested interest in promoting one over the other. The a7 setup costs quite a bit more than the E-M1 setup, primarily because of the cost of the Carl Zeiss lens.

In terms of handling - the two feels about the same weight with the a7 possibly a little lighter. The E-M1 felt very solid in my hands and if I had to defend myself, I'd swing the E-M1 at my assailant with confidence of scoring more damage points. This is not to say that the a7 is not well built. It certainly is quite a nice camera in my hands - not uncomfortable. Yet, having both in my hands, I'd say that the E-M1 inspires just a bit more confidence in terms of build quality.

I love the fact that the a7 has the power switch just under the shutter release button. This was how I was used to having things on my Nikon, and basically allowed me to turn the camera on as I raise it up to my eyes. As everyone already knows, this is not the case with the E-M1. I had not noticed it as much but with both cameras hanging off my neck, it became quite apparent that I preferred the a7 layout for the power switch. As for the rest of the buttons and dials, I think they're probably par for the course. Both feel good and easy to switch, although I had to get used to having two dials on my thumb on the a7 (which I have set for aperture and exposure compensation.)

The E-M1 powers up just a bit faster than the a7 but in all honesty, you'd have to be splitting hairs if that little difference would influence your preference one way or another. On the other hand, the a7 wakes up from sleep more quickly. With the E-M1, I found that I had to give the release a half-press and wait a bit before the image comes back into the viewfinder. Speaking of viewfinders, both EVFs look great. I did like SONY's use of more colours and their nice level indicator. The E-M1's EVF display seems less cluttered though, whereas the a7's EVF display is littered with all kinds of indications. On the other hand, I didn't really find that it got in the way of my shooting.

Once you start shooting though, the E-M1 feels so much more responsive than the a7. The camera obeys your presses instantly and without hesitation. The a7, by comparison, takes a more leisurely pace, forcing you to be more deliberate and less instinctive in capturing an image. I found myself taking more opportunistic images with the E-M1 than with the a7. The E-M1 also does it a whole lot more quietly compared to the a7 (which is already quieter than the a7r). Nevertheless, I imagine that I could learn to like the satisfying shutter-noise of the a7. This has the additional effect of announcing to the world that you're taking a photo, causing many subjects to look up to see what was going on. The E-M1 sounded like it's getting on with business, while the a7 seems to be ambling along.

After all that work, the E-M1 battery was in better shape than the a7 battery. This is, of course, non-scientific, but after about 50-60 shots, walking around with the cameras sometimes on, sometimes off, and sometimes in sleep mode, shot mostly through the EVF, the a7 battery showed 2/3rd full, while the E-M1 battery was still full.

Okay, now for some comparison images before I finish this off. Everything was shot in RAW mode and processed in Lightroom 5.3. I did tweak the images to my own liking (high contrast, high saturation) so please forgive me if that was excessive. While I shot at ISO100 (and some ISO125 on the a7) mostly, I found that I had to add some NR to the E-M1 photos since I had it turned OFF in-camera. The a7 didn't need this but I had the NR set to LOW in-camera rather than OFF. I also had to desaturate the red channel on some of the E-M1 photos as I found the reds to be too strong with my current settings.

E-M1

a7

E-M1

a7

E-M1

a7

E-M1

a7

E-M1

a7

I have more comparison shots but I think I'll just stop here for now. The colours can always be tweaked to one's own preference. I found the exposure of the E-M1 to be a bit high with center-weighted mode and had to dial in a -0.7EV on most of the shots. It also had a tendency to blow the highlights more (possibly due to it being used with ISO100) while the a7 exhibited much better dynamic range and held the highlights better in high-contrast situations.

Where the lenses are concerned, I must say that the 17mm F1.8 performed admirably. I would be quite happy to go with the DoF offered by it as I would with the Carl Zeiss. Since this was pretty much shot in daylight, I didn't have any problems with AF nor with the lack of IBIS (SONY calls theirs OSS) on the a7.

I was pleasantly surprised at how well the E-M1 held up against the full-frame a7. The a7 does perform very well in its own regard - nice colours, good AWB, EVF, DR, and of course, sharpness. At the same time, I don't feel like I'm suddenly transported into a whole new league with the a7. In many situations, the E-M1 would have been the better camera to use, while for critical image quality, I might resort to the a7.

Of course, one would expect a bit more from the a7 given how much more you pay for the overall setup. the a7r costs even more and has slower max. shutter speed, flash sync, etc. On the other hand, the a7 seems to suffer from some internal sensor reflections. I've not seen this happen and in shots with the sky, the 17mm flared (possibly due to not having any lens hood attached) while the 35mm held steady. I'm looking forward to see what both Olympus and SONY come up with next. Both the E-M1 and a7 are impressive cameras that I don't think anyone would be too disappointed with.

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

A few other minor notes - things I don't like about the cameras.

I've already mentioned that the E-M1 power switch was placed on the wrong side, and that the reds seemed a tad strong. I also don't like the fact that when the EVF is used, the backlight of the LCD screen seems to remain on, draining power unnecessarily. Then there's the problem with long exposure noise in the E-M1 that is worse than it is in the E-M5. Fortunately, this doesn't bother me too much since I rarely shoot long exposure (although I do need to from time to time.) The E-M1 dials sometimes feel a little unresponsive. One click of the dial does not result in a value change. Sometimes I need to use two clicks to get the aperture, for instance, to change. Rolling the dial vigorously seems to help a bit (maybe cleaning the contacts) but would also wear things out more quickly. They feel great - just that they're sometimes not responsive enough.
The a7 lenses are expensive, and for the moment, options are few. I also can't believe that for a camera this price, they did not include an external charger. That's right, you charge the battery in-camera through the micro-USB port. Although this is the same port on my Samsung phone, I am a little wary about plugging in and out of that port in the long term. Of course, when you're charging, you can't do anything else with the camera settings. Battery life, as I have mentioned, could be better too for this class of camera. The ability to charge via the USB port, on the other hand, would have been nice on the E-M1 since it would allow you to travel without bringing an external charger, or to charge the camera from one of those additional battery storage units that are sold for charging phones on the go.

The LCD tilting mechanism is about the same on two cameras but the one on the a7 slides out more smoothly and easily, while the E-M1 LCD mechanism feels a lot stiffer. The mount point on the a7 is centered along the lens axis, and is in fact centered on the sensor plane as well. The E-M1 mount point is off center, which can be rather annoying for some users.

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eaa
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

Just to clarify the terms:
NR is Noise Reduction, used for dark frame subtraction on long exposures.
NF is Noise Filter, used to suppress ISO noise.
I reckon it is the latter you mean here.

DR in the E-M1 is reduced by some 1.3 EV w/ ISO 100 compared to (base) ISO 200.
So you will be way better off handling harsh contrast and highlights using ISO 200.
That said, I'm surprised you found the need to run NF in post on the E-M1 ISO 100 pics here!
To me they look clean as a whistle.

For the reds I agree, provided you use ACR.
Developing the ORFs in Oly Viewer does not saturate reds that much.
Otherwise, thx for an interesting comparison.
Btw, did you sense any shutter shock on either camera?

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to eaa, 6 months ago

Yes, I meant NF then. Sorry about that - brain fart.

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ijustloveshooting
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

thanks for the effort,,, i couldnt open %100 resolutions however, from smaller views, i found A7 dof at F2.8 is much better than F1.8 oly,,,,

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to eaa, 6 months ago

Hit reply too early back there. None of my photos showed any sign of shutter induced vibration. This is possibly because I was generally shooting at relatively high shutter speeds most of the time. I had not realized how quiet the E-M1 is, having used the GF1 for so long (which is even quieter.) Now with the a7 side by side, I begin to appreciate the quietness of the shutter on the E-M1.
None of the my a7 photos exhibited any such problem either. All photos were handheld. It might be argued that the E-M1 is more prone to SS because of the floating sensor design. I had originally intended to write up an article after I attached an accelerometer to both cameras to measure the actual shutter induced vibrations in all three-axes. I've not had time to do that yet but I can tell you, even without testing, that the a7 shutter makes way more sound and vibration compared to the E-M1 shutter.
In either case, no SS spotted.
About the ISO100 on the E-M1, yes, I was aware of this. I wanted the best possible quality as far as noise is concerned, and ISO100 (LOW) is actually less noisy than at ISO200. The noise that I observed is not much at all, but neither is it super clean. Actually, I should probably call it "grain" if it makes more sense. I've attached a crop of some of the grain I'm referring to on the E-M1. Saving it to JPEG hides the grain due to the colour optimization and compression.

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

I should add that this "grain" or dithering effect can also be found in the a7 photos, just not to the same extent. As an example, you can take the loupe to the photos of the brushes (red paint brushes) and compare between the E-M1 and the a7 samples. Both have grain but it is considerably more pronounced on the E-M1 image.

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Loga
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to ijustloveshooting, 6 months ago

It's not just the bokeh - the A7 pictures are more lifelike, and more '3D', and not just because of slightly shallower DOF, but sharpness and transients. Look at that old man with that instrument.

ijustloveshooting wrote:

thanks for the effort,,, i couldnt open %100 resolutions however, from smaller views, i found A7 dof at F2.8 is much better than F1.8 oly,,,,

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Loga
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Loga, 6 months ago

However, it would have been better to set the exposure equally, even with post processing.

Loga wrote:

It's not just the bokeh - the A7 pictures are more lifelike, and more '3D', and not just because of slightly shallower DOF, but sharpness and transients. Look at that old man with that instrument.

ijustloveshooting wrote:

thanks for the effort,,, i couldnt open %100 resolutions however, from smaller views, i found A7 dof at F2.8 is much better than F1.8 oly,,,,

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MAubrey
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

Daniel Wee wrote:

I should add that this "grain" or dithering effect can also be found in the a7 photos, just not to the same extent. As an example, you can take the loupe to the photos of the brushes (red paint brushes) and compare between the E-M1 and the a7 samples. Both have grain but it is considerably more pronounced on the E-M1 image.

I'm not sure that this situation qualifies for the word "considerably" when the difference doesn't even show up in print.

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MAubrey
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Loga, 6 months ago

Loga wrote:

It's not just the bokeh - the A7 pictures are more lifelike, and more '3D', and not just because of slightly shallower DOF, but sharpness and transients. Look at that old man with that instrument.

ijustloveshooting wrote:

thanks for the effort,,, i couldnt open %100 resolutions however, from smaller views, i found A7 dof at F2.8 is much better than F1.8 oly,,,,

Color me cyncial, but I highly doubt you'd know which was which if they're weren't labeled. I hate to say it, but I think you're seeing what you want to see. Websizes don't reveal the differences. And no, I'm not a fanboy. I shoot with an A7.

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jaybp
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

Thanks for the excellent comparison! I spent a lot of time going back and forth on whether I wanted to upgrade from my E-M5 to an E-M1, or sell all my m43 gear and get an A7.

For a variety of reasons I ended up with the E-M1, but the one question I've had ever since is what the high ISO (1600+) ranges look like in comparison between the two cameras.

Do you have any examples that show the difference between the two?

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Lab D
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I liked the E-M1 pics better, but...
In reply to Daniel Wee, 6 months ago

I tried to look at the pictures before reading the text to which which was which.  I like the E-M1 pics better, but there is nothing I saw about them that couldn't be done on the A7 pics.   It is all based on MY personal preferences of colors and processing.

I would say if you like Sony cameras get the A7 and if you like Olympus get the E-M1.  Both are great tools and do more than most people need.

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Godfrey
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Daniel Wee, 6 months ago

Interesting comparison, thank you.

I also have both cameras, although I bought them to use rather differently. I use the E-M1 with FT and mFT lenses, use AF with it most of the time, and take advantage of the automation systems quite a lot. The A7 I bought to use with my Leica R and Nikkor SLR lenses, maybe a couple of M-Mount lenses (the ones that work well with its sensor), and have it set up such that shooting with it is an experience very similar to working with a manual focus film SLR with aperture priority AE and a motor drive.

  • Since I bought only the A7 body and necessary accessories (had the lenses already), and half of my lens kit for the E-M1 I already had, I compare the price of the bodies and accessories only. So far, they're running neck and neck on system expenses ... each just over $2000 when I account for body, lens mount adapters, power accessories, grips, cable remotes, etc.
  • As you noted, shooting with the E-M1 is fast and fluid where shooting with the A7 happens at a slower pace. This is true totally independent of AF as well, I don't own an AF lens for the A7 but find that even using the E-M1 with manual focusing only proves faster and more fluid than using the A7.
  • The control organization and layout on the E-M1 is very ergonomic to my hands, and the menu design very logical and easy to remember, albeit deep with many potential interactions. The A7 controls—buttons and dials—seem rather haphazardly scattered about the camera, not nearly so swift to "fall to hand." The menu system, also pretty deep and with many interactions, is very poorly organized and difficult to remember. The A7 has fewer customization options and controls than the E-M1. All that said, I have been able to set up and customize buttons and dials on both cameras such that I rarely need to dive into the menus to get something done, and the way I have them both setup the controls are easy to use and remember.
  • The biggest thing I miss on the A7 is the E-M1's superb image stabilization system. The five-axis IBIS is truly outstanding. The A7 is also more power hungry (and let's not get into the stupid decision to only supply it with very slow in-camera battery charging ... the purchase of two external chargers and three extra batteries are almost necessary for anyone trying to use this camera for serious picture taking; enough to have a battery in the camera and a spare in the bag while the other two are being recharged.
  • The biggest thing I miss on the E-M1 is the A7's excellent implementation of manual exposure with Auto-ISO. They've got that down just right, with EV Compensation and the wide dynamic range of the larger sensor you have excellent and fine control.

I've been shooting with the E-M1 since October and the A7 since last week, I'm still testing lenses for the latter. So far, the lenses I have for the A7 seem to work very well with its sensor. Image quality for both cameras is outstanding, with nuance differences related to depth of field and dynamic range—ultimately all based on the difference in the sensor size. These nuance differences are rather more subtle than it might seem, I know that if I made a series of photos with both and printed them to 11x17 inch, I would be hard-pressed to tell which camera made which photo other than because of lens/format characteristics. I would not buy either camera expecting a quantum change in image quality.

The E-M1 satisfies 99% of my shooting needs, and it could be 100%. So why did I spend the money for the A7? Because the Leica R lenses are truly wonderful and I found that using them on smaller format sensors did not bring out their best like using them with the original Leicaflex SL film camera did. The A7 does: photos made with the Summicron-R 90mm on film and with the A7 have the same lovely character. There is room for both formats in the visual language..

The E-M1 succeeds best because of its outstanding control ergonomics, wide customization options, superb lens line, fast and responsive handling and operation, and the very very good sensor. The A7 succeeds best because of its format, the outstanding sensor performance, and adaptability to use with many many wonderful older lenses. I'm happy to have and work with both cameras.

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to MAubrey, 6 months ago

Well, I almost never print but I think it would also show up if someone crops. That's when one is most likely to see the difference. That said, it's nothing serious at all - just a difference that I wanted to point out between two machines. Thus the use of "considerable" is surely relative in nature, between the two cameras, and not an absolute statement of performance.

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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to ijustloveshooting, 6 months ago

How can a depth of field of a lens be better than another?
One lens might suit the subject better, but the amout that is in focus for a given apeture, focal length and sensor size in neither better nor worse than another (in my mind anyways).

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to jaybp, 6 months ago

I have a few images from the a7 taken at ISO1600 but these were not taken under controlled conditions, and were JPEG, not RAW. Furthermore, the NF (noise filter) on the a7 was on the LOW setting, whereas the E-M1 was being shot in RAW with all noise reduction turned off. I may do more tests along these lines if I can find the time (and remember to) but off hand, it would seem to me that the noise is more controlled in the a7 at ISO1600 compared to the E-M1. This is particularly so with colour noise. That, and the higher resolution of the a7, which allows for down-sampling, means that it produces cleaner images when used at ISO1600 (what I have images of.)

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GBC
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Turning off the LCD in the back
In reply to Daniel Wee, 6 months ago

If you hold down the LCD button, you get the option to turn off the LCD completely.
The auto eye level swithing is disabled, but it will save your battery. I use the switch instead of the auto switch mostly now to save on the battery life, plus I never use the LCD unless I am reviewing images or using a tripod.
Thanks for the great post.

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Daniel Wee
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to GBC, 6 months ago

If I read the context of what he's writing (not everyone here uses English as their first language), I would assume that by "better" he means that:-
1. He prefers a shallower DoF for subject isolation

2. He means that the F2.8 on the full-frame a7 yields a shallower DoF than the F3.6 equivalent of the m4/3 E-M1.

As long as you see it like that, there's nothing too unusual about what he is saying.

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KwhyChang
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Re: A quick day out with the Olympus E-M1 and the SONY a7
In reply to Godfrey, 6 months ago

I also have both cameras and I found your assessment to be similar to mine.

Similar to Godfrey, I had FF lenses that weren't being used.

I must say I really enjoy using the both cams, but especially the A7. I have a few Zeiss rangefinder lenses that I really like using on the A7.

I do trust the µ4/3 system more to get the shot, because as was mentioned shooting is more slower paced with the A7.

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