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07-08-2019, 11:51 AM   #16
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QuoteOriginally posted by mccririck Quote
Exposing to the right does not mean blowing the highlights! If you're blowing the highlights you're going too far!
As I said, it's all a matter of balance. Small blown highlights mean more captured detail in the bottom end on wide DR images.

07-08-2019, 11:51 AM - 1 Like   #17
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QuoteOriginally posted by mccririck Quote
Exposing to the right does not mean blowing the highlights! If you're blowing the highlights you're going too far!
I think that's roughly the point I was trying to make...your initial post seemed to be implying that ETTR is something one should always be trying to do. One shouldn't assume that trying to do ETTR makes sense in all situations. In very high dynamic range situations, even at what the camera sees as a neutral exposure, you may have both dark shadows and blown highlights. See Normhead's photo below. That's at -1. At 0, those spots in the sky would already have been really bright(i.e. blown out).

So in a situation like that, trying to apply a rule like ETTR is only going to make things worse. No way around that without a GND filter or doing an HDR merge of multiple images and exposure settings(in which case are doing both ETTR and ETTL). Or you can spot meter a brighter part of the scene, effectively causing the scene to have a lower "zero". Then maybe you could ETTR. But that is basically doing the same thing as using a matrix meter that sets the "zero" higher and doing ETTL.

And to answer your initial question on blinkies, I don't use them, as I find them too annoying, largely for the reasons that we're discussing here.
07-09-2019, 06:18 AM   #18
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The histogram is derived from the in camera processed jpg setup. I've found from the K-1 that what parameters are chosen for saving the jpg file can affect the histogram especially the high end. In shooting "Bright", the right edge of the display is usually higher than for "Natural." Neither one really represents the RAW data. If shooting jpg only, that is fine but for RAW shooters are not getting much benefit from the histogram or blinkee.....

I've requested of Pentax a number of times to offer a RAW histogram but have never heard anything from them.

Do any of the other brands offer a RAW histogram?

RONC
07-09-2019, 06:27 AM - 1 Like   #19
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QuoteOriginally posted by rechmbrs Quote
The histogram is derived from the in camera processed jpg setup. I've found from the K-1 that what parameters are chosen for saving the jpg file can affect the histogram especially the high end. In shooting "Bright", the right edge of the display is usually higher than for "Natural." Neither one really represents the RAW data. If shooting jpg only, that is fine but for RAW shooters are not getting much benefit from the histogram or blinkee.....

I've requested of Pentax a number of times to offer a RAW histogram but have never heard anything from them.

Do any of the other brands offer a RAW histogram?

RONC
That's crazy, I've completely learned how to interpret raw exposures from the "natural" setting. As long as your settings are constant, and honestly, as a raw shooter you shoudn't even be missing around with the jpeg settings, the camera repeats the same processing every time. It's not at all irregular. You can figure it out. And if in doubt, just like with film, bracket.

Now if you want to go through every jpeg setting and figure them all out fine, it's not necessary but if you're genius, have at it. Honestly, this has never occurred to me, even once.

07-10-2019, 06:30 AM - 1 Like   #20
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QuoteOriginally posted by rechmbrs Quote
The histogram is derived from the in camera processed jpg setup. I've found from the K-1 that what parameters are chosen for saving the jpg file can affect the histogram especially the high end. In shooting "Bright", the right edge of the display is usually higher than for "Natural." Neither one really represents the RAW data. If shooting jpg only, that is fine but for RAW shooters are not getting much benefit from the histogram or blinkee.....
Yes, not news - I said this two days ago.

QuoteQuote:
I've requested of Pentax a number of times to offer a RAW histogram but have never heard anything from them.

Do any of the other brands offer a RAW histogram?

RONC
ETTR is not for 'amateurs' - you have to know what you are doing.

I repeat my comment #12:

'Blinkies' and histograms are based on what a JPEG will show. The photographers I know of who talk most about ETTR become very familiar with their cameras, and almost don't need a light-meter to guide their decision-making.

added: To be honest with you, I couldn't depend on my camera's built-in light meter in the Age of Film. I shot slide film, and the metering seemed to be primarily aimed at users of negative film, so even then I had to use my own judgement as much as the meter. I use the techniques I developed back then even though I usually use the JPEG images created by my camera.

Last edited by reh321; 07-10-2019 at 06:35 AM.
07-10-2019, 06:58 AM - 3 Likes   #21
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It may not be 100% match but it's enough to work with.

I set my camera to -.7 all the time... when I bracket, most of the time the original setting is what I end up using the image from. My guess is a "natural" histogram allows me to make an accurate exposure between 80% and 90% of the time. And if I'm in any doubt at all, I bracket.

People seem to assume that there should be no scene with lighting so complex an auto-exposure camera can't nail it. That's not my experience with Pentax, and I've never heard anyone claim perfect exposure on any system.

The jpeg engine is remarkably good. When I tried to match the jpeg of a sunset I took, it took me close to a half hour. The raw was better in the end, but man oh man. The jpeg engine makes spot exposure adjustments that if you're not using some very high end software you aren't going to be able to mimic. You're going to need a white balance brush to come close.

Raw used to be a necessity... these days, I'm not so sure it is.

Last edited by normhead; 07-10-2019 at 07:30 AM.
07-10-2019, 09:20 AM   #22
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QuoteOriginally posted by normhead Quote
People seem to assume that there should be no scene with lighting so complex an auto-exposure camera can't nail it. That's not my experience with Pentax, and I've never heard anyone claim perfect exposure on any system.
That was exactly my experience with my Super Program using slide film - perhaps the higher 'latitude' of negative film gave better results. At first i thought this was a "Pentax issue", but I found exactly the same thing when I got a Canon EOS Elan. With slide film I always bracketed after a while. With my digital cameras, I find that they get it close enough in a 'normal shot' {nothing really challenging, such as shooting into the sun} that I don't have to bracket ..... I can make a minor "levels adjustment" to the JPEG.
07-10-2019, 10:22 AM   #23
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QuoteOriginally posted by reh321 Quote
Yes, not news - I said this two days ago.

ETTR is not for 'amateurs' - you have to know what you are doing.

I repeat my comment #12:

'Blinkies' and histograms are based on what a JPEG will show. The photographers I know of who talk most about ETTR become very familiar with their cameras, and almost don't need a light-meter to guide their decision-making.

added: To be honest with you, I couldn't depend on my camera's built-in light meter in the Age of Film. I shot slide film, and the metering seemed to be primarily aimed at users of negative film, so even then I had to use my own judgement as much as the meter. I use the techniques I developed back then even though I usually use the JPEG images created by my camera.
My entry was added to emphasize that the histogram does not represent what one might think it does. The manufacturers are not giving us what they should as far as optimization of raw data. What I didn't mention was "what does the histogram really mean." unless there is other info, the histogram can be very misleading.
RONC

07-10-2019, 11:42 AM   #24
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QuoteOriginally posted by rechmbrs Quote
My entry was added to emphasize that the histogram does not represent what one might think it does. The manufacturers are not giving us what they should as far as optimization of raw data. What I didn't mention was "what does the histogram really mean." unless there is other info, the histogram can be very misleading.
RONC
I think we need an example....
It's plausible, but, I'm not just taking someone's word for something like that.

Especially since trusting the histogram except when the curve goes off both sides of the frame has worked so well for me in the past.
07-10-2019, 04:00 PM   #25
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I don't really understand how the blinkies could work for jpeg but not RAW. Are you saying if you took the perfect ETTR photo and then converted it to jpeg the highlights would be blown?
07-10-2019, 05:27 PM   #26
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QuoteOriginally posted by mccririck Quote
I don't really understand how the blinkies could work for jpeg but not RAW. Are you saying if you took the perfect ETTR photo and then converted it to jpeg the highlights would be blown?
Are you saying if you took the perfect ETTR photo there might not be less than optimal shadow detail?

This is getting real obtuse.
07-10-2019, 06:27 PM - 5 Likes   #27
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QuoteOriginally posted by mccririck Quote
I don't really understand how the blinkies could work for jpeg but not RAW. Are you saying if you took the perfect ETTR photo and then converted it to jpeg the highlights would be blown?
Yes, a perfect ETTR RAW photo might blow out highlights in JPG.

The important issue with RAW is that blinkies and histogram can only be correctly computed AFTER a white balance and color space is determined which is a JPG or post-processing setting. Sure, you could just look at the RAW data values to test for clipping in R, G, or B, but that implies assuming a white balance and color space that has equal gains of 100% on all the colors (actually it's worse or more complicated than that due to color correction matrix which can include both positive and negative cross-contribution terms which can mean the signal in one color could cause a different color to blow-out).

In general, a white balance setting might boost an unblown color into blow-out by correcting for the lack of some color of light from that light source. For example, a picture of a bright blue ball lit by tungsten light might have RAW blue channel values well under the clipping value. But when white balance corrects for the lack of blue light in tungsten lighting, the pixels of the blue ball might blow-out.

Camera makers could show a RAW histogram for ETTR purposes but the photographer would need mad skillz in color science to correctly interpret the relationship between the RAW values and the developed ones.
6 Days Ago - 1 Like   #28
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QuoteOriginally posted by photoptimist Quote
Camera makers could show a RAW histogram for ETTR purposes but the photographer would need mad skillz in color science to correctly interpret the relationship between the RAW values and the developed ones.
Exactly, the art of producing a decent image would be very difficult to codify. And codifying would reduce photography from an art form to series of same looking images. There are some things you never want to give up control of, and decisions about how to interpret the light you are seeing with camera is the most obvious. You do it by knowing your tool, and experience. Which is why this argument is futile. Every shortcut has it's issues ETTR is not different. That being said there will be scenes where ETTR is appropriate. It's the opportunities you miss when it's not that will be the problem.

If I had to make up an acronym for what I do it would be "Expose for the Available Light". With modern high DR cameras, expose to the left will be as appropriate in as many situations as expose too the right will be. And soemtimes "keep the highest part of the curve in the centre (or to the left or right of centre)" is the appropriate approach. I fail to see how ETTR dude came to the conclusion that adopting 1 of of those possibilities is the correct one. Possibly a function of your average colour film having half the DR of a K-1 has something to do with it. No shadow detail could be rescued from unexposed areas of film, there was nothing there.

Bottom line, if you're learning photography there are no acceptable cheats. You have to chimp, look at your histogram, then decide how to adjust accordingly. I haven't come up with any rules to help with that. IMHO, each case stands on it's own.
6 Days Ago - 3 Likes   #29
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QuoteOriginally posted by normhead Quote
Exactly, the art of producing a decent image would be very difficult to codify. And codifying would reduce photography from an art form to series of same looking images. There are some things you never want to give up control of, and decisions about how to interpret the light you are seeing with camera is the most obvious. You do it by knowing your tool, and experience. Which is why this argument is futile. Every shortcut has it's issues ETTR is not different. That being said there will be scenes where ETTR is appropriate. It's the opportunities you miss when it's not that will be the problem.

If I had to make up an acronym for what I do it would be "Expose for the Available Light". With modern high DR cameras, expose to the left will be as appropriate in as many situations as expose too the right will be. And soemtimes "keep the highest part of the curve in the centre (or to the left or right of centre)" is the appropriate approach. I fail to see how ETTR dude came to the conclusion that adopting 1 of of those possibilities is the correct one. Possibly a function of your average colour film having half the DR of a K-1 has something to do with it. No shadow detail could be rescued from unexposed areas of film, there was nothing there.

Bottom line, if you're learning photography there are no acceptable cheats. You have to chimp, look at your histogram, then decide how to adjust accordingly. I haven't come up with any rules to help with that. IMHO, each case stands on it's own.
Exactly!

ETTR is about using exposure settings that maximize the dynamic range and minimize the noise source in the RAW data. What's clever and important about ETTR is that it explicitly optimizes exposure for data collection purposes rather than insisting that middle gray in the scene should be middle gray in the RAW or JPG file. Thus, a proper ETTR RAW file for an image of a black cat on a black couch might look like a gray cat on a gray couch in the SOOC JPG but it would enable creation of the smoothest possible final image and the recovery of the inkiest blacks in the shadows between the cat and couch.

That said, ETTR can't be applied mechanically in a lot of situations because the DR of the scene vastly exceeds the DR of the camera. The sun, in particular, is upwards of 16-17 EV brighter than the any of the sun-lit middle gray objects in the scene and those sun-lit middle gray objects might be a great many EV brighter than important objects in the shadows (e.g., picnickers under a tree). That's where the photographer's judgment comes in to determine what can be blown-out, whether the image needs to be reframed to avoid acceptable blow-outs, whether a fill-flash or reflector can illuminate the shadows, or whether the image is not worth taking because of unfavorable lighting conditions.

I also think ETTR can also create trouble if the scene has small but important highlights (e.g., colored holiday lights, the colored disk of a rising sun, etc.) that cover so few pixels that the histogram looks like it could tolerate more pushing to the right when, in reality, the colored lights are blown-white.

Shortcuts and rules can only be a starting point for getting a good image. A big part of photography is learning which shortcuts or rules can or can't be used in a given scene with a given photographic goal.
6 Days Ago - 1 Like   #30
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QuoteOriginally posted by rechmbrs Quote
I've requested of Pentax a number of times to offer a RAW histogram but have never heard anything from them.
It's easy to get a raw histogram, select jpeg style natural and drop the contrast parameter in that style, you now get histogram and blinkies represent how the image data is within the range of raw coding.

---------- Post added 11-07-19 at 19:00 ----------

QuoteOriginally posted by rechmbrs Quote
the histogram can be very misleading
The histogram says where the image data is located on a scale from 0 to max value (you know that). In case of bell shaped histogram, camera auto-exposure centers the histogram, no issue. In case of U shaped histogram the camera can't know what you want to prioritize in the image, you as a user have to decide if you leave the exposure centered (in that case both shadows and high-lights are crippled), or if you shift exposure to the right to save shadows at the expense of high lights, or if you shift exposure to the left to save the high-lights at the expense of shadows. No camera tech so far can read your mind to know what you want to achieve with the image.

---------- Post added 11-07-19 at 19:10 ----------

QuoteOriginally posted by photoptimist Quote
Camera makers could show a RAW histogram for ETTR purposes but the photographer would need mad skillz in color science to correctly interpret the relationship between the RAW values and the developed ones.
I've sometimes been surprised that my K1 in matrix mode underexposed when looking at the lightness histogram, only to discover that the AE matrix algorithm had underexposed to avoid clipping the red channel, the histogram for the red was at the right while other colors when relatively shifted about one stop to the left. But nowhere in the camera it is possible to tell the camera what to prioritize, the algorithm on the K1 prioritizes colors over noise.

Last edited by biz-engineer; 6 Days Ago at 10:02 AM.
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