Camera Raw: 32 Bit Toning Error when converting to 16 bit/channel

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So here's the deal - I'm an avid user of HDR and have always made my HDRs in photoshop (but tonemapped elsewhere). Now, with the new tonemapping in ACR I can get great results - BUT - there's a BIG problem.
After I've created my HDR and toned it in ACR it opens in photoshop as a 32 bit file (with the camera raw adjustments showing as a filter).
And it looks great.
BUT, when I try to make that a usable file by converting down to 16 or 8 bit - all that work goes to waste.
I've always used "exposure and gamma" to convert from 32 to 16 or 16 to 8 - that's the one we all know and love because it doesn't change anything as far as the image appearance.

However - with HDRs I create and tone in ACR: Once I do this to convert to 16 bits using exposure and gamma (like always and touching nothing) - the image turns almost white - horribly washed out and lousy looking. I've tried it every way I can think of. I'll flatten the 32 bit file as to get rid of the acr smart filter, I've rasterized the layer, I've duplicated the document, I've tried merging and not merging - everything. The preview that shows when I am about to convert 32 to 16 in exposure/gamma looks correct, but as soon as I do it - boom - washed out weird looking image.

Other issue:
If I save a 32 bit psd after toning in ACR to work on later - it looks way different the next time I open it. This happens whether I save the profile along with the file or not. It opens darker, for the most part and I can never get back to how it was (and was unable to save as 32, 16, or 8 looking right!).

Last issue: If I create a 32 bit hdr image but choose NOT to tone in acr and save it as a radiance file - if I open that radiance file later in photoshop and use the acr filter to tone it - again, it appears way different like a lot of data has been lost. The image is usually a lot brighter, washed out, less colorful, and the pixels seem to not be able to bend very far in any direction.

Can someone please explain if I am doing something wrong?? Or if this is a bug?? I love the way the 32 bit images look once I've toned them - but that's the only time they'll look remotely like that! Can't save, convert to 16 bit, or do doodly squat without the image drastically changing!
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Joe lekas

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Posted 5 years ago

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Steve Sprengel, Champion

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32-bit floating-point (HDR) images are always opened in Photoshop and Lightroom as "scene-referred" (raw data) rather than "output-referred" (have a color-space that tells us the gamma) and so PS and LR always assume they are linear gamma and convert them to a normal non-linear for viewing, which is why they brighten.

The ONLY ways for a 32-bit images to show up again the same way upon reopening in PS is to either convert it to 16 or 8 bit as part of the HDR-toning process (meaning they are not 32-bit, anymore) OR to keep the ACR-toning smart-filter intact so it can be re-done on the fly every time the image is opened.

See raw-engineer Eric Chan's responses to a similar topic a couple days ago:
http://feedback.photoshop.com/photosh...
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Joe lekas

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Yep - I'm aware of this - but that's not the problem. It's the converting to 16 or 8 bit that is the problem. And it isn't a minor change - it's drastic. I was on with adobe help today (they took control of my computer) and no one could figure out how to resolve this problem.
Once I've created the 32 bit image from (in this case 3 exposures) - I tone it in ACR with photoshop cc and then have it open in photoshop. Now. If I save THAT as a psd with the acr-toning-smart-filter intact - it STILL opens again looking all funky and weird.
The other alternative - converting to 16 or 8 bits is where the main problem comes in. I will flatten out the 32 bit file so that the acr-toning-smart-filter is now rasterized with the image and (hey, i've also tried it without flattening just to check) when I go to image>mode>16 bits per channel (as always) - I am presented with the photoshop hdr toning dialog box where I scroll up to "exposure and gamma" - change no settings - and hit ok. This has always worked for me for switching between bit modes and the image remains 99% the same. However - like the attached image - the result is that the image changes drastically to the point of being useless.
Do you see what I'm saying?
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Steve Sprengel, Champion

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Here is my result for your steps 5 and 5 (6), above. With the GPU turned on in Preferences / Performance I see a very slight difference in contrast, pictured, below, 16-bit left, 32-bit right. If I turn off the GPU settings, then I see no difference. To me this suggests my video card isn't dealing with my monitor profile exactly right:


I did figure out how to make previously-saved 32-bit document (yours on Dropbox) look the same as it did when saved, rather than washed out, when it is re-opened, later, without an ACR-toning smart-filter included. The trick is to turn on your profile mismatch warnings and Convert to Working Profile instead of Use Embedded Profiles. This works because the embedded profile has a linear gamma but the working profiles have a non-linear gamma so if you convert the gamma is changed and the image is darker:
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Joe lekas

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Ok! Thank you everyone for taking the time to help me figure this out! I appreciate it!
I have taken everyone's advice into consideration and tried everything suggested - watched every video - read every link - and here's where I'm at now.

There's some good news and bad news and just plain weird news.

I do have those profile settings enabled (always have) - and it does ask me if I want to embed, convert, or discard.
If I flatten a 32 bit toned image (to get rid of the acr filter) and save it as a 32 bit tiff - I can re-open that tiff with convert to working space on - and it looks the same. I can ALSO convert that tiff to 16 bit and have it look a LOT closer to the original (nothing like the washed out ones). That's good news!
However, if I save the 32 bit toned image with the acr filter still there as PSD - it will open washed out and crazy the next time I open it (using convert to working space - I've also tried every other option). So - working on a 32bit toned in acr image again is still impossible after closing it without it looking all washed out.

ALSO - there is one section in color profile settings that is puzzling me and affects all of this in a major way.
Above the three boxes to check about profile mismatches and warnings - there are 3 settings
RGB, CMYK, and Gray.
Now by default my RGB settings was RGB: Off
I know this is a weird issue because my working space is adobe rgb and the profile mismatch warnings are still on - so the same result happens when opening files. And also by checking the include the working color profile with an image when you save it should achieve the same result as haveing RGB: Preserve Embedded Profiles on. But there's a weirder area this causes a difference.

If I have that RGB setting OFF - and merge those 3 same images to hdr and then go to tone in ACR it looks really dark (not a problem it's a 32 bit hdr file - I use acr to make it look the way I want). It's rich in color and seems to have loads of data and tone available to play with.

HOWEVER - if I start with that RGB setting to "Preserve embedded profiles" - then merge those same 3 images to hdr and then go to tone in ACR it looks entirely different. It looks way less dark and contrasty, is very drained in color, and seems to have a lot less data to play with in terms of bringing out shadows or toning down highlights.

It's best for me to just show you a side by side - as I'm including here. This is the same hdr created with no changes other than that one setting (shown in the image) being different before I merge to hdr. (And the 32bit image that opens in ACR I have made zero changes to at the point of screen capture).

Any ideas?
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Steve Sprengel, Champion

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Normal to washed-out is linear-gamma (dark) increased to normal (2.2) gamma.
Normal to dark is normal gamma (2.2) decreased to linear-gamma.

How do things act coming out of ACR Toning if you have Convert set?

Can you post your 32-bit-with-acr-filter-intact on dropbox -- the one that opens brighter after you save it?

Do things act differently when you have the GPU settings turned off in Preferences / Performance, just to make sure your video-card doesn't have some strange luminance or gamma setting that is confusing the issue.
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Joe lekas

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Ok - I'm posting 2 psds to dropbox.

This reflects the attached jpeg (same as my last post) - where the hdrs look totally different with no adjustments depending on if that setting in color profiles for rgb is on "off" or "preserve embedded."

They are both 32 bit psds made from the same 3 raw images and sent to "tone in acr" - only I didn't adjust a thing in acr I just hit ok.

Oddly - the one that looks really really dark is chalk full of tone and more range and color than the lighter one.

https://www.dropbox.com/sh/qg9bsln8r8...
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Dan Watkins

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Convert 32bit to Smart object.
Then convert 32 smart to 16.
Then flatten.
You're welcome.