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09-20-2018, 03:05 PM   #16
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QuoteOriginally posted by dms Quote
But if you want to learn about exposure (e.g., be able to judge how much exposure adjustment to make) looking at the screen after every shot is a godsend--as it gives us instant feedback. Pre-digital we took notes of the shots, and then weeks later saw the developed film, but (except for a Polaroid camera/back) that was the way to get the most complete feedback.

Actually rereading your post, I think you meant you are doing it, but would prefer to see it in the viewfinder. I agree the screen can be problematic, especially so if it is sunny.
Hi! Yes, correct, I'm trying to get precise exposure without the display, having only viewfinder.


QuoteOriginally posted by runswithsizzers Quote
kislotiq, Your '255, 255, 255' represents the maximum brightness for JPEG or TIFF files which are 8-bit - but a raw file should be 12 or 14-bit. Which have much higher levels of maximum brightness, right?

What raw editor are you using to recover your highlights and/or boost the shadows when post processing?
I use CaptureOne. I recover highlights by dragging exposure left until there's no clipping and then use curves to add contrast to shadows or highlights.
I believe that RGB(255, 255, 255) should represent the maximum value of the original color space, no matter how deep.

---------- Post added 09-20-18 at 03:07 PM ----------

QuoteOriginally posted by Adam Quote
Indeed, as UncleVanya said, highlight correction automatically underexposes by one stop, then lifts the shadows.

It is equivalent to shooting with an exposure compensation of -1 and doing some PP in RAW, i.e. it does affect the exposure parameters.
Oh, I did not expect that, thanks for info!

09-20-2018, 03:19 PM - 1 Like   #17
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QuoteOriginally posted by kislotiq Quote
...So I want to ask you experienced guys on how to improve this workflow?
TLDR: Try matrix metering rather than spot, and don't agonize about highlights. What I say may or may not be applicable to your case.

There are many different kinds of "street photography". My style, which I'm still developing, shows people as they go about their day. I don't want them to react to me or pose, so I don't have time to carefully compose. I usually shoot in TAv mode: shutter fast enough to freeze motion, aperture stopped down a little for depth of field, pre-focused 2 meters away.

I use matrix metering to help the camera select ISO in TAv. Always use DNG format so I can adjust exposure later.

Sometimes those settings will blow out highlights. I can try highlight recovery in Lightroom. If the highlights are too far gone, it doesn't much matter because the subject is more important than the background, anyway. I'd rather have a bad background than a subject that's too dark and turns overly noisy when I brighten shadows.

Blown highlights might matter more if your "street photography" is more about the buildings. You can still use matrix metering. Turn on bracketing and pick the brightest, least-blown exposure later.

Here are 2 examples where the subjects were in deep shadows cast by tall buildings. The background had more sunlight. Getting the highlights correct would have meant subjects looking too dark. In hindsight, the subjects have potential but I didn't catch them at especially interesting moments, so the photos could be better. The blown highlights are irrelevant and probably out of focus, anyway, because I'm focused close.

09-20-2018, 03:41 PM   #18
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QuoteOriginally posted by kislotiq Quote
... I recover highlights by dragging exposure left until there's no clipping and then use curves to add contrast to shadows or highlights. ..
I'm confused. If you are able to recover the highlights and boost shadows in post, then what's the problem?

When you say: "... when a piece of sky comes into the composition - it's almost always overexposed if there's a small patch of it or under-exposed if it's a major element in composition" - the terms 'underexposed' and 'overexposed' are only applicable to the 8-bit JPEG or TIFF, right? If the values you need are present in the raw file, I don't understand how this is an exposure problem.
09-20-2018, 03:49 PM   #19
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QuoteOriginally posted by runswithsizzers Quote
kislotiq, Where are you seeing those numbers when looking at a raw file? Your '255, 255, 255' represents the maximum brightness for JPEG or TIFF files which are 8-bit - but a raw file should be 12 or 14-bit. Which have much higher levels of maximum brightness, right?
JPG is 8 bit. TIFF and raw (DNG, PEF) offer more bits and more precision but not much more maximum brightness. For discussion sake, lets's compare 8 bit JPG to 16 bit TIFF. 8-bit can store 0 to 255. 16-bit can store 0 to 65535.

255 JPG = 65535 TIFF and if you hit either number then the respective color channel is blown out.

Pretend you exposed a little short of blown out. The next lower number in JPG is 254. In TIFF, you have all the numbers between 65280 and 65535, that's 256 tiny steps while JPG only gives you 1 step.

Another rough way of thinking of 16-bit is like decimal, with 8-bit on each side. JPG has no decimal, able to store 254.0 or 255.0 with nothing in-between. TIFF provides 254.1 through 254.255 to represent smaller steps between the one JPG step. Once you hit 254.256 it turns into 255.0.

(the math above is crude but I hope it demonstrates how the advantage of raw is extra precision in similar-but-different shades)

Here's an illustration (link to web, not my photo) how more bits = more precision. All the bit depths achieve the same minimum black and the same maximum white. https://fstoppers.com/education/can-you-see-difference-between-10-bit-and-8-...footage-166977




09-20-2018, 04:33 PM   #20
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QuoteOriginally posted by DeadJohn Quote
JPG is 8 bit. TIFF and raw (DNG, PEF) offer more bits and more precision but not much more maximum brightness. For discussion sake, lets's compare 8 bit JPG to 16 bit TIFF. 8-bit can store 0 to 255. 16-bit can store 0 to 65535.

255 JPG = 65535 TIFF and if you hit either number then the respective color channel is blown out.

Pretend you exposed a little short of blown out. The next lower number in JPG is 254. In TIFF, you have all the numbers between 65280 and 65535, that's 256 tiny steps while JPG only gives you 1 step.

Another rough way of thinking of 16-bit is like decimal, with 8-bit on each side. JPG has no decimal, able to store 254.0 or 255.0 with nothing in-between. TIFF provides 254.1 through 254.255 to represent smaller steps between the one JPG step. Once you hit 254.256 it turns into 255.0.

(the math above is crude but I hope it demonstrates how the advantage of raw is extra precision in similar-but-different shades)

Here's an illustration (link to web, not my photo) how more bits = more precision. All the bit depths achieve the same minimum black and the same maximum white. Can You See the Difference Between 10-Bit and 8-Bit Images and Video Footage? | Fstoppers

Thanks for the clarification. For further clarification, not all TIFFs are 16-bit, some are 8-bit.

But bit depth is probably the wrong way to talk about to the OPs problem, which, if I understand it, is more about dynamic range.

Correct me if I'm wrong, but wouldn't the fact that highlight detail can be recovered from the raw file prove that the dynamic range of the scene did not exceed the dynamic range of the sensor, and therefore there was no overexposure?
09-20-2018, 04:58 PM   #21
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QuoteOriginally posted by runswithsizzers Quote
...Correct me if I'm wrong, but wouldn't the fact that highlight detail can be recovered from the raw file prove that the dynamic range of the scene did not exceed the dynamic range of the sensor, and therefore there was no overexposure?
I think software highlight recovery gets fairly sophisticated and can make guesses about overexposed areas from adjacent non-blown areas.

Let's say you have a patch of pixels at 90% red, 45% green, 45% blue. (Perhaps it's the sky near a sunset.) That's a 2:1 ratio of red to the other channels.

In the middle of the patch there's a smaller blown-out patch at 100% red, 100% green, 100% blue where the sun is. If you dial back the highlights, software could theoretically use the adjacent 2:1 ratio to know the overexposure should be reduced to 50% green and blue when red is 100%.

Here's how one software developer describes their process How white balance and highlight recovery works
09-22-2018, 07:50 AM   #22
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QuoteOriginally posted by runswithsizzers Quote
Correct me if I'm wrong, but wouldn't the fact that highlight detail can be recovered from the raw file prove that the dynamic range of the scene did not exceed the dynamic range of the sensor, and therefore there was no overexposure?
When I described my workflow, it was a generic example. Sometimes the highlights are fine, but sometimes they cannot be recovered.

Dynamic range of the scene rarely exceeds sensor's, I just tend to push the histogram right as much as possible while trying not to clip the highlights and not to look at the screen.
So if I enable highlight recovery in camera and it underexposes all my shots by one stop it defies the original purpose of exposing to the right.
09-22-2018, 03:05 PM   #23
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QuoteOriginally posted by kislotiq Quote
When I described my workflow, it was a generic example. Sometimes the highlights are fine, but sometimes they cannot be recovered.

Dynamic range of the scene rarely exceeds sensor's, I just tend to push the histogram right as much as possible while trying not to clip the highlights and not to look at the screen.
So if I enable highlight recovery in camera and it underexposes all my shots by one stop it defies the original purpose of exposing to the right.
Do you have problems with shadow recovery when you are 1 stop shy of ettr?

10-13-2018, 06:19 AM   #24
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There is only interest to expose for the high lights at ISO100 to avoid blown highlight. At ISO200, the sensor is underexposed by 1 ev (from sensor physical dynamic range), ISO400 underexpose by 2 ev. , ISO800 underexposes by 3 ev. etc.. (ISO200 , 1 ev of highlight can be recovered by underexposing 1 ev in post), etc. At ISO100, the best way to have no highlight blown out without having the camera reset to a different exposure is to set the camera to M mode, exposure compensation to +2ev, press the green button, and that's all: from that point , all shoots will be exposed without burned high lights unless the lighting changes, if the light source changes then same procedure again. There is no "free lunch", doesn't seem like camera have a mode that expose for the highlights, because sometime the highlight is out of interest for a photographs, and the rest of the image would suffer less quality just for protecting a tiny piece of highlight area that is not playing a role in the image. It's up to the photographer to decide what to do for getting the best possible images depending on what the photograph should emphasize in a scene.
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