Expose to the right (ETTR) or underexpose?

[dwbell]

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Agreed BUT shadows are a problem on cameras like the 5D2 as they quickly shows lines in deep shadows when pulled too hard. In my experience, M9 files are far more tolerant in this respect.

 

Yes, I ETTR on my 5DII in the studio. Not on my M9 in the wild.

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[Jaybob]

No offence Jay, but I'm not sure what you want? The discussion was of the benefits of ETTR. He posted an interesting comparison of severe ETT*L*. What's wrong with contributing to the academic discussion as he did, in your view?

 

"It seems like you misunderstand how digital photography fundamentally works" and "You managed this far because camera makers decided to call camera gain "ISO,"" and "If the photographer doesn't understand the concept, I doubt a client would." and "I'm not going to take the time to do tests which you can do on your own..."

 

These are things that were said to me during the couse of this "academic" discussion.

 

radical ideas and people who present them are often quite difficult to take seriously when they're wrapped up so pretty.

 

For me, if it's ONLY about what digital information you have left to process later, (isn't it?) Posts 104 through 108 are where the fundamentals of ETTR RAW exposure are broken down to their core and explained pretty well. There's more stuff on the right than there is on the left, and it's less noisy.

 

Typing DEFINITELY makes me sound like a douchebag, but all I'm doing is pushing accepted science.

 

Jay

Edited October 19, 2012 by Jaybob

[douglasf13]

"It seems like you misunderstand how digital photography fundamentally works" and "You managed this far because camera makers decided to call camera gain "ISO,"" and "If the photographer doesn't understand the concept, I doubt a client would." and "I'm not going to take the time to do tests which you can do on your own..."

 

Jay

 

My apparently harsh quotes were in reference to your earlier post:

 

"This statement, from beginning to end, is inaccurate, except for "don't blow highlights".

 

Regardless of camera model, sensor type, film stock, OR ISO, "proper" exposure will always yield a better technical photograph. The BEST way to accomplish proper exposure in digital photography is to utilize ETTR. The only real "correctable" mistake you can make shooting RAW is in white balance, exposure errors will almost always compromise the image quality, unless of course, that's what you're looking for."

 

If you're now saying that your post was incorrect, then I will gladly retract those comments. Your above comment implies that ISO is part of exposure, which is not the case in digital. You may use it to calculate exposure, but it isn't a part of exposure itself. Either way, I apologize if they're were too harsh in the first place. I'm not saying that you're not a great photographer. I'm just saying that digital cameras may not work quite like you think they do.

 

As to the M9 push examples I posted earlier,http://www.l-camera-forum.com/leica-forum/leica-m9-forum/195838-expose-right-ettr-underexpose-7.html#post2212407, both files were exposed identically, imported into LR4 with the identical, standard import settings. The only thing the I changed was that I gave them identical white balances, and I boosted ONLY the exposure slider of the ISO 160 file. That's it. I'm curious which one you think is ISO 160 boosted.

Edited October 19, 2012 by douglasf13

[trond]

Thank you Jay, I fully agree!

 

I have been following this "discussion" with great amusement

 

There is only one single optimal exposure in a digital capture system, and that is to place the brightest pixel(s) at level 255 (@ 8 bit) or 16383 (@ 14 bit).

 

This exposure will give you three important things:

 

1. It will preserve all highlights without clipping.

2. It will maximize the shadow detail.

3. It will minimize the noise in the image.

 

This is all what ETTER (Expose To The Extreme Right) is all about.

 

Any lesser exposure will compromise point 2 and 3 above.

 

With this optimal exposure we have preserved all possible tone levels that our camera can handle.

 

Then in digital post possessing, we can use any desired tone mapping curve to suit the output medium; print, screen or projection.

 

Anyone that would like to have less shadow detail or more noise, can still add that in post processing.

 

However, lost shadow details or details blocked by noise due to sloppy exposure, can never be recovered in digital post.

 

That said, this is not always easy to achieve in the "heat of the action" doing street photography.

 

Best regards

 

Trond

[douglasf13]

To me the IQ vs. usability is the point. What surprises me is that there is so much discussion (some of which is certainly interesting) about theory when its not at all difficult to actually TRY suggested techniques. One of the maddening things about digital photography is a perception by some that understanding every last detail of theory will somehow produce better images. In my experience, getting out and taking photographs and trying things out in an old fashioned practical way is a far more productive approach. I've tried techniques which, whilst they work in practice, are too complicated and time consuming for the marginal increases in apparent (ie actually viewed) image quality, that they produce. And surely this is the point here.

 

Using ETTR is a very valid technique which I use when I consider it appropriate. But its not always appropriate and can sometimes lead to too much time dealing with an images in post processing. Fascinating as much theory is, using it isn't always as practical as might be hoped for, but fortunately we are able to think for ourselves and make decisions about how we apply technique based on our own requirements. Good thread though!

 

Oh, I agree. The usable advantage of sticking to base ISO in all conditions is that one essentially never blow highlights, because, by not raising ISO, you're not telling the camera's gain to clip what could have been a good exposure. However, then you have to adjust every image in the raw converter, although you'd have to do that with an ETTR image, too. Either way, I usually still raise ISO to a single number, like 800, in lowlight, so that I have a starting point for calculating exposure.

[douglasf13]

Thank you Jay, I fully agree!

 

I have been following this "discussion" with great amusement

 

There is only one single optimal exposure in a digital capture system, and that is to place the brightest pixel(s) at level 255 (@ 8 bit) or 16383 (@ 14 bit).

 

This exposure will give you three important things:

 

1. It will preserve all highlights without clipping.

2. It will maximize the shadow detail.

3. It will minimize the noise in the image.

 

This is all what ETTER (Expose To The Extreme Right) is all about.

 

Are you implying that the camera ISO is part of that exposure? Or are you speaking only about base ISO?

 

If you're talking about base ISO, then I'd agree, at least in terms of SNR. The one thing that can be a negative about ETTR is color, and exposing midtones too far to the right can cause hue twists in the raw converter.

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(...) exposing midtones too far to the right can cause hue twists in the raw converter.

 

Is this the case even when none of the color channels are overexposed (i.e., clipped)?

[Jaybob]

If you're now saying that your post was incorrect, then I will gladly retract those comments. Your above comment implies that ISO is part of exposure, which is not the case in digital. You may use it to calculate exposure, but it isn't a part of exposure itself. Either way, I apologize if they're were too harsh in the first place. I'm not saying that you're not a great photographer. I'm just saying that digital cameras may not work quite like you think they do.

 

...both files were exposed identically, imported into LR4 with the identical, standard import settings. The only thing the I changed was that I gave them identical white balances, and I boosted ONLY the exposure slider of the ISO 160 file. That's it. I'm curious which one you think is ISO 160 boosted.

 

Brother, I dont care what you do, what comments you retract, or what file is what. The technique you're advocating (even if it works perfectly in theory or practice) is the ass backward way to go about it. Photography is hard enough, I dont need the extra level of mental gymantics that leaves me with a file I still have to fix. So, no, thank you.

Edited October 19, 2012 by Jaybob

[douglasf13]

Brother, I dont care what you do, what comments you retract, or what file is what. The technique you're advocating (even if it works perfectly in theory or practice) is the ass backward way to go about it. Photography is hard enough, I dont need the extra level of mental gymantics. So, no, thank you.

 

Hey, that's fine by me. I'm not here to lecture on someone changing their technique. Just kinda trying to explain how things work.

[pop]

Douglas and Jay, can't we just assume that you won't going to agree soon and drop the personal notes, please?

[Jaybob]

Yes, sir.

[douglasf13]

Is this the case even when none of the color channels are overexposed (i.e., clipped)?

 

Yes, but any examples that I've seen of it in the past were subtle at best, so it may not affect most of us, practically speaking. If you're a stickler for accurate color, it may bother you.

 

I just remembered that the Chromasoft blog has several articles about ETTR, and this one shows an example of the color issue: ChromaSoft: Why "Expose to the Right" is just plain wrong

 

p.s. I'm sorry if I've somehow made this all personal. I'll be more careful.

[sandymc]

Is this the case even when none of the color channels are overexposed (i.e., clipped)?

 

Yes.

 

Sandy

[trond]

Are you implying that the camera ISO is part of that exposure? Or are you speaking only about base ISO?

 

If you're talking about base ISO, then I'd agree, at least in terms of SNR. The one thing that can be a negative about ETTR is color, and exposing midtones too far to the right can cause hue twists in the raw converter.

 

Dear Douglas,

 

The camera should be set to the ISO where the dynamic range is maximum.

 

This is usually base ISO, or sometimes one step above base ISO, as is the case f.ex with the Canon 5D2.

 

Best regards

 

Trond

Edited October 19, 2012 by trond

[k-hawinkler]

And a couple of 100% crops:

 

 

Image 1 crop A:

 

Image 2 crop B:

 

Image 1 crop B:

 

Image 2 crop B:

 

It looks pretty close to me, and Lightroom isn't really the best raw converter for this technique. Can you tell which is which?

 

 

 

Very close for sure. Now pixel peeping. My eyes aren't good enough for this.

But a friend tells me he thinks images 1 are smoother than images 2.

Can you tell by comparing the .DNG files?

Thanks.

[dwbell]

Gosh Jay, I was being polite and genuinely interested in your point.

 

Not to worry though. You guys have at it. Me? Not so much. Enjoy!

[Jaybob]

Gosh Jay, I was being polite and genuinely interested in your point.

 

 

sorry for the misunderstanding..my comments were not directed at you

[douglasf13]

Very close for sure. Now pixel peeping. My eyes aren't good enough for this.

But a friend tells me he thinks images 1 are smoother than images 2.

Can you tell by comparing the .DNG files?

Thanks.

 

Hi. Yep, these were from DNG's converted identically out of Lightroom 4 at Adobe's standard baseline settings, except that the ISO 160 file had the exposure slider at +2.90 EV. Pretty close, huh? I'm pretty sure I wouldn't be able to tell which is which. Plus, apparently Lightroom isn't the best converter to do this with, either, because of the way that it handles shadows, according to those that understand the technology more than I do.

 

With cameras that have linear DR like the M9, lots of MFDBs, Sony EXMOR cameras, etc., the amount of light getting to the sensor, which I would call exposure, is the important part. Changing ISO, while useful in calculating what your exposure should be, isn't technically necessary. With other cameras, like Canon DSLRs and the pro Nikon sports DSLRs that don't use Sony sensors, it is more beneficial to boost in-camera ISO, at least up to a point, because of the design of their ADCs.

 

Actually, to take this to a more confusing level, most cameras fall somewhere in between, where the in-camera ISO performs better up to a point, and then the raw converter push is better past that point. It just depends on the camera. In fact, with the Fuji X100, if you set ISO 3200, it actually just shoots at ISO 1600, and then the raw metadata tells the raw converter to push the exposure +1.0 EV under the hood without any indication of it doing so. Tricky! Some MFDB cameras do that with all ISOs above base ISO.

 

While this info may or may not be practical in all cases, here is one case where not upping the ISO may be helpful. Imagine you're in low light, and your camera is set to ISO 800, f2 and 1/30. Your meter/histogram tells you that you're "underexposed," so you have to decide your next step:

 

1) You could open up the aperture, but you're already at max aperture, so it isn't an option.

2) You could slow down your shutter speed, but, you don't want to, because you'll risk too much subject movement.

3) You can raise ISO, which will move your histogram to the right.

 

With the M9, step 3 is not necessary, because your raw converter is just as good at pushing the exposure as your camera, and, by pushing ISO in-camera, you risk over compensating and accidentally blowing out highlights. That's the beauty of sticking with the lower ISO. You don't risk blowing highlights by allowing the camera to do the gain boost. When I shoot the M9 in lowlight, I usually know what aperture and shutter are my bare minimum, so, once I have those set, the ISO kind of doesn't matter, unless you boost the ISO too much and blow the highlights. It's safer to just leave the ISO where it is and boost in the converter, assuming, like Jaybob mentioned, that you don't have to give the actual raw files to a client, because they might think you don't know what you're doing.

 

Does that make sense at all?

 

p.s. picture 1 was the ISO 160 file boosted by +2.9 EV, so your friend preferred that over the native ISO 1250 file. it's a super close call.

Edited October 19, 2012 by douglasf13

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[dwbell]

Interesting stuff.

 

Maybe a silly question. Is there any algorithmic stuff involved in increasing the exposure in computer? Such that with later / better process versions you will get a "better" exposure increase than the (relatively) primitive in camera processing? Or is +2Ev just a simple pure amplification of data wherever it's performed?

[douglasf13]

Interesting stuff.

 

Maybe a silly question. Is there any algorithmic stuff involved in increasing the exposure in computer? Such that with later / better process versions you will get a "better" exposure increase than the (relatively) primitive in camera processing? Or is +2Ev just a simple pure amplification of data wherever it's performed?

 

This does vary converter to converter, but you'd have to ask someone more knowledgeable than me about the each converter's methods. Iliah Borg once explained to me why RPP is better at doing this than Lightroom (at least at the time,) but I don't recall the conversation and the exact reasoning.

Edited October 19, 2012 by douglasf13