A good read in the mirrorless vs DSLR debates

[JamieTux]

rossdoyle wrote:

Richard wrote:

rossdoyle wrote:

JamieTux wrote:

They have the dof of an f1.2 lens no? So they are really f/1.2, just not T1.2

If the light past f/1.6 is not recorded by the sensor, then no, the DOF is not any shallower than f/1.6. In fact, the light probably does eventually reach the sensor after scattering all around the camera innards, so you basically just get a washed-out f/1.6 equivalent DOF image.

I don't think that is correct, DOF is out of focus. So if I turn the focus ring and put the lens out of focus it does not matter how much light reaches the sensor, it is still OOF.

I am not an expert in this but when I shoot at 1.2 with a 7d, it does not look washed out.

Well, you are right, I guess "washed out" is probably too strong of an expression, since most of the scattered light will just be absorbed by the black inner walls of the camera and lens. It's probably more accurate to say that the scattered light slightly reduces contrast. It's hard to estimate this effect, though, since we do not have a way to compare to something (we have no way to NOT block that light from reaching the same performance sensor).

Regarding the DOF/focus issue, think about the fact that higher angle of incidence light will be rejected by the structures covering the sensor, once the angle is high enough. Microlenses and electronic structures on CMOS sensors contribute to this. If the light past a certain aperture is not reaching the sensor, it does not matter whether it is due to the lens iris or the microlens or CMOS electronic layer. It has the same effect on DOF.

Also, two more issues -- some camera makers may mask this effect by boosting metering by a known amount when you go to large aperture. Pentax K-5 does not seem to do this and I see my Pentax-A 50mm f/1.2 meter too dark at f/1.2-f/1.6. And finally, different camera sensors have some differences in this effect depending on their exact physical characteristics.

Hi Ross,

Thanks for the information and explanation - however despite sounding logical it doesn't fit with my experience.

The Leica Noctilux definitely has less DOF at f0.95 than at f1.4 - I only got to use it for a little while but there was a noticeable difference (I realise that the Leica M9 has angled microlenses so that could be a difference) - likewise the Canon 85L appears to have less DOF than I have seen with any other lens of the same focal length at f1.4. I don't have much personal experience of this so that's anecdotal but my observatoin.

Would you be able to take shots and post them with your Pentax to demonstrate that the DOF is the same from 1.2 to 1.6 if you get a chance please? If this is a photography "FACT" that I need to unlearn I'd like to start!

Thanks Ross

 

[Richard]

I have heard this before

rossdoyle wrote:

Richard wrote:

I don't think that is correct, DOF is out of focus. So if I turn the focus ring and put the lens out of focus it does not matter how much light reaches the sensor, it is still OOF.

I am not an expert in this but when I shoot at 1.2 with a 7d, it does not look washed out.

Well, you are right, I guess "washed out" is probably too strong of an expression, since most of the scattered light will just be absorbed by the black inner walls of the camera and lens. It's probably more accurate to say that the scattered light slightly reduces contrast.

As far as contract, even on film cameras where there is no loss due to sensor contrast went down and cameras with fstops in the .95 to 2.0 that is just the way it works.

As far as the amount of light. This is an interesting test, though it could be the camera sensor sensitivity being increased but it is in manual. I do not see washed out though. And remember there is not a lot of difference between F1.2 and 1.4 1.4 to 2.0 is one full stop

http://vimeo.com/28007649

It's hard to estimate this effect, though, since we do not have a way to compare to something (we have no way to NOT block that light from reaching the same performance sensor).

Regarding the DOF/focus issue, think about the fact that higher angle of incidence light will be rejected by the structures covering the sensor, once the angle is high enough. Microlenses and electronic structures on CMOS sensors contribute to this. If the light past a certain aperture is not reaching the sensor, it does not matter whether it is due to the lens iris or the microlens or CMOS electronic layer. It has the same effect on DOF.

I will disagree with you on this. This has been tested before, I remember reading this before I bought the 85 1.2

http://www.wlcastleman.com/equip/reviews/85mm/mann_port/mann_port.htm

You can see there is a difference though not alot but there is a difference between 1.2 and 1.4 as far as Out Of Focus OOF. The difference between 1.2 and 1.8 is even bigger. You can see the lines behind the mannequin get narrower as you stop down in the link above. Below is the full test and you can review the full sized images yourself.

Here is the complete article.

Loading…

www.wlcastleman.com

Also, two more issues -- some camera makers may mask this effect by boosting metering by a known amount when you go to large aperture. Pentax K-5 does not seem to do this and I see my Pentax-A 50mm f/1.2 meter too dark at f/1.2-f/1.6. And finally, different camera sensors have some differences in this effect depending on their exact physical characteristics.

 

[Richard]

JamieTux wrote:

rossdoyle wrote:

Richard wrote:

rossdoyle wrote:

JamieTux wrote:

They have the dof of an f1.2 lens no? So they are really f/1.2, just not T1.2

If the light past f/1.6 is not recorded by the sensor, then no, the DOF is not any shallower than f/1.6. In fact, the light probably does eventually reach the sensor after scattering all around the camera innards, so you basically just get a washed-out f/1.6 equivalent DOF image.

I don't think that is correct, DOF is out of focus. So if I turn the focus ring and put the lens out of focus it does not matter how much light reaches the sensor, it is still OOF.

I am not an expert in this but when I shoot at 1.2 with a 7d, it does not look washed out.

Well, you are right, I guess "washed out" is probably too strong of an expression, since most of the scattered light will just be absorbed by the black inner walls of the camera and lens. It's probably more accurate to say that the scattered light slightly reduces contrast. It's hard to estimate this effect, though, since we do not have a way to compare to something (we have no way to NOT block that light from reaching the same performance sensor).

Hi Ross,
Thanks for the information and explanation - however despite sounding logical it doesn't fit with my experience.

The Leica Noctilux definitely has less DOF at f0.95 than at f1.4 - I only got to use it for a little while but there was a noticeable difference (I realise that the Leica M9 has angled microlenses so that could be a difference) - likewise the Canon 85L appears to have less DOF than I have seen with any other lens of the same focal length at f1.4. I don't have much personal experience of this so that's anecdotal but my observatoin.
Would you be able to take shots and post them with your Pentax to demonstrate that the DOF is the same from 1.2 to 1.6 if you get a chance please? If this is a photography "FACT" that I need to unlearn I'd like to start!

Thanks Ross

I don't think you need to unlearn. I agree with your observations. I believe this shows this as well. Notice the lines behind the mannequins head as the get narrower.

http://www.wlcastleman.com/equip/reviews/85mm/mann_port/mann_port.htm

The full article

Loading…

www.wlcastleman.com

 

[happysnapper64]

DenWil wrote:

Just bored people with nothing better to do. There's probably a vacuum cleaner forum where the debate is bag or bag less.

Special people.

Definately bagless, plus Hoovers' pet hair facility is useless compared to Dyson. :-D

 

[The Davinator]

rossdoyle wrote:

JamieTux wrote:

sportyaccordy wrote:

Richard wrote:

sportyaccordy wrote:

The glass is a legitimate reason to stick with DSLRs for sure, but 1.2 glass on a DSLR is a myth...

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

So you are saying that 1.2 is an incorrect designation for a lens or 1.4? I disagree, the lens is the lens, it allows so much light in. The Fstop is a theoretical maximum. Now if you were to say there were no TStop 1.2 lenses, I would agree but this takes into account amount of light loss.

Now the sensor may not be able to take advantage of the extra light to various degrees. So it is not an issue with the lens. The lens manufacturer is not trying to cover up something, their lens is indeed an f 1.2 or 1.4 but the camera may or may not allow that much light to the sensor.

No, I am not disputing the aperture of the lens at all. I am sure it is what they say it is. The question is how useful it is on a digital sensor. According to that letter, not very below ~f/1.6. I mean the shots look beautiful, but when push comes to shove they are not really f/1.2.

They have the dof of an f1.2 lens no? So they are really f/1.2, just not T1.2

If the light past f/1.6 is not recorded by the sensor, then no, the DOF is not any shallower than f/1.6. In fact, the light probably does eventually reach the sensor after scattering all around the camera innards, so you basically just get a washed-out f/1.6 equivalent DOF image.

Well, as I've conpared DOF differences between f 1.6, 1.2 and f1 on cameras and obtained a shallower DOF with each step, you'd be wrong. I also noticed no drop in contrast attributable to light scatter....so you'd be wrong there as well. Funny how many people have ever tried this and yet spout off like experts.

 

[sportyaccordy]

Dave Luttmann wrote:

rossdoyle wrote:

JamieTux wrote:

sportyaccordy wrote:

Richard wrote:

sportyaccordy wrote:

The glass is a legitimate reason to stick with DSLRs for sure, but 1.2 glass on a DSLR is a myth...

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

So you are saying that 1.2 is an incorrect designation for a lens or 1.4? I disagree, the lens is the lens, it allows so much light in. The Fstop is a theoretical maximum. Now if you were to say there were no TStop 1.2 lenses, I would agree but this takes into account amount of light loss.

Now the sensor may not be able to take advantage of the extra light to various degrees. So it is not an issue with the lens. The lens manufacturer is not trying to cover up something, their lens is indeed an f 1.2 or 1.4 but the camera may or may not allow that much light to the sensor.

No, I am not disputing the aperture of the lens at all. I am sure it is what they say it is. The question is how useful it is on a digital sensor. According to that letter, not very below ~f/1.6. I mean the shots look beautiful, but when push comes to shove they are not really f/1.2.

They have the dof of an f1.2 lens no? So they are really f/1.2, just not T1.2

If the light past f/1.6 is not recorded by the sensor, then no, the DOF is not any shallower than f/1.6. In fact, the light probably does eventually reach the sensor after scattering all around the camera innards, so you basically just get a washed-out f/1.6 equivalent DOF image.

Well, as I've conpared DOF differences between f 1.6, 1.2 and f1 on cameras and obtained a shallower DOF with each step, you'd be wrong. I also noticed no drop in contrast attributable to light scatter....so you'd be wrong there as well. Funny how many people have ever tried this and yet spout off like experts.

How did you compare the DOF? By a subjective, seat of the pants, bias confirming (i.e. "I paid for this F/1 lens so I see a difference that justifies my purchase) "analysis"? Plus nobody said there is no difference; the report said the bokeh was not as pronounced as the science would indicate, and then they explained why. Also, nobody said anything about contrast. Bottom line, I take DPR's laboratory tests and unbiased + educated conclusions over your emotion fueled wholly subjective defenses over your purchases anyday. There is nothing to argue- manufacturers realized large aperture lenses hit a point of diminshing returns around ~1.6 and built in correction into their cameras to follow suit. That doesn't mean the lenses are worthless- for example while you might not get the full f/1.2, the lens might still be sharper and have higher IQ throughout than a slower lens. Wide open speed + performance isn't everything.

 

[The Davinator]

sportyaccordy wrote:

Dave Luttmann wrote:

rossdoyle wrote:

JamieTux wrote:

sportyaccordy wrote:

Richard wrote:

sportyaccordy wrote:

The glass is a legitimate reason to stick with DSLRs for sure, but 1.2 glass on a DSLR is a myth...

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

So you are saying that 1.2 is an incorrect designation for a lens or 1.4? I disagree, the lens is the lens, it allows so much light in. The Fstop is a theoretical maximum. Now if you were to say there were no TStop 1.2 lenses, I would agree but this takes into account amount of light loss.

Now the sensor may not be able to take advantage of the extra light to various degrees. So it is not an issue with the lens. The lens manufacturer is not trying to cover up something, their lens is indeed an f 1.2 or 1.4 but the camera may or may not allow that much light to the sensor.

No, I am not disputing the aperture of the lens at all. I am sure it is what they say it is. The question is how useful it is on a digital sensor. According to that letter, not very below ~f/1.6. I mean the shots look beautiful, but when push comes to shove they are not really f/1.2.

They have the dof of an f1.2 lens no? So they are really f/1.2, just not T1.2

If the light past f/1.6 is not recorded by the sensor, then no, the DOF is not any shallower than f/1.6. In fact, the light probably does eventually reach the sensor after scattering all around the camera innards, so you basically just get a washed-out f/1.6 equivalent DOF image.

Well, as I've conpared DOF differences between f 1.6, 1.2 and f1 on cameras and obtained a shallower DOF with each step, you'd be wrong. I also noticed no drop in contrast attributable to light scatter....so you'd be wrong there as well. Funny how many people have ever tried this and yet spout off like experts.

How did you compare the DOF? By a subjective, seat of the pants, bias confirming (i.e. "I paid for this F/1 lens so I see a difference that justifies my purchase) "analysis"? Plus nobody said there is no difference; the report said the bokeh was not as pronounced as the science would indicate, and then they explained why. Also, nobody said anything about contrast. Bottom line, I take DPR's laboratory tests and unbiased + educated conclusions over your emotion fueled wholly subjective defenses over your purchases anyday. There is nothing to argue- manufacturers realized large aperture lenses hit a point of diminshing returns around ~1.6 and built in correction into their cameras to follow suit. That doesn't mean the lenses are worthless- for example while you might not get the full f/1.2, the lens might still be sharper and have higher IQ throughout than a slower lens. Wide open speed + performance isn't everything.

Interesting. I compare, and according to you it's emotion filled bias. Might I suggest you pull the chip off your shoulder and give it a try yourself. It seems it's you sputtering with emotion....and I'm pretty certain you've never done a comparison yourself.

 

[Richard]

sportyaccordy wrote:

Dave Luttmann wrote:

rossdoyle wrote:

JamieTux wrote:

sportyaccordy wrote:

Richard wrote:

sportyaccordy wrote:

The glass is a legitimate reason to stick with DSLRs for sure, but 1.2 glass on a DSLR is a myth...

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

So you are saying that 1.2 is an incorrect designation for a lens or 1.4? I disagree, the lens is the lens, it allows so much light in. The Fstop is a theoretical maximum. Now if you were to say there were no TStop 1.2 lenses, I would agree but this takes into account amount of light loss.

Now the sensor may not be able to take advantage of the extra light to various degrees. So it is not an issue with the lens. The lens manufacturer is not trying to cover up something, their lens is indeed an f 1.2 or 1.4 but the camera may or may not allow that much light to the sensor.

No, I am not disputing the aperture of the lens at all. I am sure it is what they say it is. The question is how useful it is on a digital sensor. According to that letter, not very below ~f/1.6. I mean the shots look beautiful, but when push comes to shove they are not really f/1.2.

They have the dof of an f1.2 lens no? So they are really f/1.2, just not T1.2

If the light past f/1.6 is not recorded by the sensor, then no, the DOF is not any shallower than f/1.6. In fact, the light probably does eventually reach the sensor after scattering all around the camera innards, so you basically just get a washed-out f/1.6 equivalent DOF image.

Well, as I've conpared DOF differences between f 1.6, 1.2 and f1 on cameras and obtained a shallower DOF with each step, you'd be wrong. I also noticed no drop in contrast attributable to light scatter....so you'd be wrong there as well. Funny how many people have ever tried this and yet spout off like experts.

How did you compare the DOF? By a subjective, seat of the pants, bias confirming (i.e. "I paid for this F/1 lens so I see a difference that justifies my purchase) "analysis"? Plus nobody said there is no difference; the report said the bokeh was not as pronounced as the science would indicate, and then they explained why. Also, nobody said anything about contrast. Bottom line, I take DPR's laboratory tests and unbiased + educated conclusions over your emotion fueled wholly subjective defenses over your purchases anyday. There is nothing to argue- manufacturers realized large aperture lenses hit a point of diminshing returns around ~1.6 and built in correction into their cameras to follow suit. That doesn't mean the lenses are worthless- for example while you might not get the full f/1.2, the lens might still be sharper and have higher IQ throughout than a slower lens. Wide open speed + performance isn't everything.

Well I agree with Dave, it has been my observation too. Here are some test that prove, I can see the difference between F1.2 an 1.8 Between 1.2 and 1.4 there is a difference but much smaller, but then it is only 1/3 of a stop.

http://www.wlcastleman.com/equip/reviews/85mm/mann_port/mann_port.htm

Here is the whole article

Loading…

www.wlcastleman.com

 

[Midwest]

DenWil wrote:

Just bored people with nothing better to do. There's probably a vacuum cleaner forum where the debate is bag or bag less.

LOL, probably there is a forum where people are declaring that the hand mixer makes countertop blenders obsolete.

 

[JamieTux]

Richard wrote:
I don't think you need to unlearn. I agree with your observations. I believe this shows this as well. Notice the lines behind the mannequins head as the get narrower.

http://www.wlcastleman.com/equip/reviews/85mm/mann_port/mann_port.htm

The full article

http://www.wlcastleman.com/equip/reviews/85mm/index.htm

Yeah - that's what I was expecting to see but I'm open minded and if Ross proves his point with images I'll pay attention - until then I'll keep thinking the same

 

[paulski66]

DenWil wrote:

Just bored people with nothing better to do. There's probably a vacuum cleaner forum where the debate is bag or bag less.

Special people.

Maybe the best post I'v read on any forum, anywhere, for weeks.

 

[xpatUSA]

It wasn't too difficult to resist the temptation to respond to a thread that started out with 'F1.2' in the title but, unfortunately, the open-letter provided a considerable amount of amusement all it's own.

One lives in hope that the 'T-stop' will die a natural death before it embeds itself in the lexicon.

P.S. anyone know the Reynolds number of a mini-vac tube?

--
Regards,
Ted http://kronometric.org
SD9, SD14, GH1

 

[sportyaccordy]

Like I said, there's more to the difference between the two lenses than the apertures.

 

[ragmanjin]

DenWil wrote:

Just bored people with nothing better to do. There's probably a vacuum cleaner forum where the debate is bag or bag less.

Special people.

I used to sell Kirby vacuums door-to-door when I was 17, and honestly, that job sealed the deal for me. Bullet-proof kevlar fan, 5-speed automatic transmission built into the handle, enough suction to pull ALL of the dead skin and dust mite eggs out of a 10-inch-deep luxury pillow-top mattress and/or lift the entire box the vacuum came in...absolutely the Phase One of the Vacuum world.

That said, I've vacuumed my apartment once since we moved in....a year and a half ago......with a $30 vacuum from London Drugs. I think my wife did once, too. All of those things I know about Eureka being a fraud is totally lost on my actual lifestyle (if you think I'm lying, pour a bit of flour into your carpet, mash it in with your foot, vacuum it and then mash it with your foot again to see that all the flour is still in there. With Kirby, not so). Instead I come here to argue about things I actually have an emotional investment in and use every day.

BTW, Kirby is a bag system. Way better than the bagless garbage with the expensive commercials....speaking of expensive commercials, who was it that hired Ashton Kutcher to promote their inferior sub-par cameras all over TV again?

Probably doesn't matter.

--

 

[ragmanjin]

ragmanjin wrote:

DenWil wrote:

Just bored people with nothing better to do. There's probably a vacuum cleaner forum where the debate is bag or bag less.

Special people.

I used to sell Kirby vacuums door-to-door when I was 17, and honestly, that job sealed the deal for me. Bullet-proof kevlar fan, 5-speed automatic transmission built into the handle, enough suction to pull ALL of the dead skin and dust mite eggs out of a 10-inch-deep luxury pillow-top mattress and/or lift the entire box the vacuum came in...absolutely the Phase One of the Vacuum world.

That said, I've vacuumed my apartment once since we moved in....a year and a half ago......with a $30 vacuum from London Drugs. I think my wife did once, too. All of those things I know about Eureka being a fraud is totally lost on my actual lifestyle (if you think I'm lying, pour a bit of flour into your carpet, mash it in with your foot, vacuum it and then mash it with your foot again to see that all the flour is still in there. With Kirby, not so). Instead I come here to argue about things I actually have an emotional investment in and use every day.

BTW, Kirby is a bag system. Way better than the bagless garbage with the expensive commercials....speaking of expensive commercials, who was it that hired Ashton Kutcher to promote their inferior sub-par cameras all over TV again?

Probably doesn't matter.

--

This thread's really filling up with people who have opinions about vacuums, eh? I never thought I'd be partial to certain vacuum and diaper brands when I was a kid, but life does that to you I guess. Huggies and Kirby 4 Life. Represent.

--

 

[ragmanjin]

sportyaccordy wrote:

The glass is a legitimate reason to stick with DSLRs for sure, but 1.2 glass on a DSLR is a myth...

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

A physical measurement in a lens is a myth. Right. Yeah, there's light loss with any lens, but to say the whole f/1.2 measurement is a myth is absolute rubbish. Check this out:

Hell, a 0.7 lens isn't even a "myth" as you claim: http://petapixel.com/2013/08/05/zei...two-of-the-largest-aperture-lenses-ever-made/

--

 

[tko]

It's a myth according to one article that has never been independently verified. As usual, DXO never tell you how they obtained the results. Funny how people disbelieve their sensor numbers, but believe this. I guess it's whether they are on your side on not.

Actually, even that article admits, by it's own number, that 1.2 glass works just fine.

Going from 1.4 to 1.2 should give you 36% more light. According to the DXO figures, you only get 24% more light. OK, not as good as expected, but still a clear benefit.

You want me to do the math for going from F2.8 to F1.2 and see who wins?

sportyaccordy wrote:

The glass is a legitimate reason to stick with DSLRs for sure, but 1.2 glass on a DSLR is a myth...

http://www.luminous-landscape.com/essays/an_open_letter_to_the_major_camera_manufacturers.shtml

 

[CFynn]

Mirrorless vs DSLR - people will choose one or the other (or both) for various reasons - I think both are here to stay in one form or another - but anyway ultimately both are camera sales.

If the market really shifts from DSLRl to mirrorless - or ever settles on one or two particular sensor sizes - both Canon and Nikon are capaple of bringing out competitive systems at short notice. Sometimes the tortoises win the race.

That long race may only have strarted - in ten or fifteen years who knows who will be in the lead?

 

[TrapperJohn]

Gawd, that 85 1.2 is a sweet lens. It shows the same razor sharp, leap out at you definition that one finds in the best Leica M or Oly SHG ZD lenses.

But... you're really looking at two types of photographs, out of dozens of styles. Portrait, and picking one person or one thing out of an otherwise busy scene.

Steve's photos make me want to run out and grab a 5DII or 5DIII and an 85 1.2, while also keeping my EM5 for the scenarios where it really shines: discrete, small, light, but still very good IQ.

Arrrgh! So many options, so little money...

 

[57LowRider]

TrapperJohn wrote:

Gawd, that 85 1.2 is a sweet lens. It shows the same razor sharp, leap out at you definition that one finds in the best Leica M or Oly SHG ZD lenses.

But... you're really looking at two types of photographs, out of dozens of styles. Portrait, and picking one person or one thing out of an otherwise busy scene.

Steve's photos make me want to run out and grab a 5DII or 5DIII and an 85 1.2, while also keeping my EM5 for the scenarios where it really shines: discrete, small, light, but still very good IQ.

Arrrgh! So many options, so little money...

Know what you mean. As a committed Fuji X user, some of those 85 shots made me drool more than a bit - the butterflies are perfect. Unfortunately, unless I hire a bearer to lug the stuff around, I can't go there.