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Chaos Corona for 3ds Max => [Max] I need help! => Topic started by: Correntes on 2017-06-14, 13:07:04

Title: Corona image editor saved images gamma
Post by: Correntes on 2017-06-14, 13:07:04
Why i can“t open corona exrs saved from CIE in after effects ?
And why CIE exr are with the exposure and gamma completely off ?

Mind that i don't have any issue in after effects with corona exr and regular exr saved from frame buffer.
Title: Re: Corona image editor saved images gamma
Post by: JoeVallard on 2017-06-14, 22:02:26
I'm having the same issue as well. Opening EXRs (In Photoshop) saved from CIE looks as if the tonemapping isn't being applied and for some strange reason the hdri background is really dark. Checked the photo below, you can see in the PNG and EXR have less contrast and the highlights aren't getting toned down, as well as the background issue.
Title: Re: Corona image editor saved images gamma
Post by: Ondra on 2017-06-16, 14:35:52
yes, the tonemapping is not applied by design - the files are meant to be opened by CIE, and tonemapping is not baked in, so it can be changed in CIE
Title: Re: Corona image editor saved images gamma
Post by: JoeVallard on 2017-06-16, 22:05:21
yes, the tonemapping is not applied by design - the files are meant to be opened by CIE, and tonemapping is not baked in, so it can be changed in CIE

I'm opening up my renders in CIE, applying tone mapping, LUT, and denoising. Then clicking "Save All". The picture i posted is of the renders saved out in that format via CIE. In CIE i can't save them as EXR otherwise when i open them in photoshop none of the post processing I did in CIE is there and the HDR background is very dark. I've tried loading the alpha as transparency and alpha, neither work.

Last week i was having the same issue, but loading the EXR with the alpha as transparency seemed to work fine. The background was present and all the tone mapping was there.

If i'm not mistaken I installed the 1.6.1 hotfix this week, so that may have been the difference between this week and last week.
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-19, 11:13:45
Hi, please, could you upload the CXR image so I can inspect it? Use our private uploader for that: https://corona-renderer.com/upload/

The save button saves EXR, PNG, BMP, or JPEG files with tone mapping (current element only), and CXR files with just tone mapping settings inside to be able to modify it in CIE any time later (all elements). The pixel data itself are not affected by saving into the CXR format.
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-19, 13:03:36
standart exr. format saves from CIE also without Tone Mapping?!!!!
It seems that it is so---because There is a big difference between exr. saved from VFB and exr. saved from CIE??
In my opinion this should be the same thing:))
If this is so, then it is not very convenient for final editing and adding effects in PS and others third-party applications in 32bit colorspace:))
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-19, 14:29:05
OK, I need some test data - please, can someone upload a max scene or CXR file for me so I can inspect the issue?

BTW, is LUT file correctly loaded in CIE (is it same as in VFB)? There is a bug (see https://forum.corona-renderer.com/index.php/topic,16462.msg103495.html#msg103495) that CIE fails to load LUT file sometimes. This should be fixed in next daily build.
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-19, 16:17:14
OK, I need some test data - please, can someone upload a max scene or CXR file for me so I can inspect the issue?

BTW, is LUT file correctly loaded in CIE (is it same as in VFB)? There is a bug (see https://forum.corona-renderer.com/index.php/topic,16462.msg103495.html#msg103495) that CIE fails to load LUT file sometimes. This should be fixed in next daily build.

Ok///
I discovered the problem...
The problem in old,good 3dMax:)
Sometime the scenes from old collections even with INPUT Gamma 2.2, having OUTPUT Gamma 1.0////
During saving, cxr. file was saving with Gamma 1.0 /must be 2.2////
Also sometimes on creating NEW scene Max using old setting from previous opened project... if this was GAMMA OUTPUT 1.0, as this is a problem for new created project///
A big inconvenience than last version's of 3dmax all this parameter's of Output Gamma are hidden//and can't controlled directly via preferences menu///
Solution:--- using script "Gamma Setting" or something like this for all new projects, and make this for all old works:)

Title: Re: Corona image editor saved images gamma
Post by: alexyork on 2017-06-19, 16:18:27
OK, I need some test data - please, can someone upload a max scene or CXR file for me so I can inspect the issue?

BTW, is LUT file correctly loaded in CIE (is it same as in VFB)? There is a bug (see https://forum.corona-renderer.com/index.php/topic,16462.msg103495.html#msg103495) that CIE fails to load LUT file sometimes. This should be fixed in next daily build.

Ok///
I discovered the problem...
The problem in old,good 3dMax:)
Sometime the scenes from old collections even with INPUT Gamma 2.2, having OUTPUT Gamma 1.0////
During saving, cxr. file was saving with Gamma 1.0 /must be 2.2////
Also sometimes on creating NEW scene Max using old setting from previous opened project... if this was GAMMA OUTPUT 1.0, as this is a problem for new created project///
A big inconvenience than last version's of 3dmax all this parameter's of Output Gamma are hidden//and can't controlled directly via preferences menu///
Solution:--- using script "Gamma Setting" or something like this for all new projects, and make this for all old works:)

Can confirm. Huge annoyance.
Title: Re: Corona image editor saved images gamma
Post by: maru on 2017-06-19, 16:37:45
Here is how to set up gamma in newer versions of Max (scroll down to the very bottom):
https://coronarenderer.freshdesk.com/support/solutions/articles/5000515647
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-19, 16:39:03
OK, I need some test data - please, can someone upload a max scene or CXR file for me so I can inspect the issue?

BTW, is LUT file correctly loaded in CIE (is it same as in VFB)? There is a bug (see https://forum.corona-renderer.com/index.php/topic,16462.msg103495.html#msg103495) that CIE fails to load LUT file sometimes. This should be fixed in next daily build.

Ok///
I discovered the problem...
The problem in old,good 3dMax:)
Sometime the scenes from old collections even with INPUT Gamma 2.2, having OUTPUT Gamma 1.0////
During saving, cxr. file was saving with Gamma 1.0 /must be 2.2////
Also sometimes on creating NEW scene Max using old setting from previous opened project... if this was GAMMA OUTPUT 1.0, as this is a problem for new created project///
A big inconvenience than last version's of 3dmax all this parameter's of Output Gamma are hidden//and can't controlled directly via preferences menu///
Solution:--- using script "Gamma Setting" or something like this for all new projects, and make this for all old works:)

P.S.---In addition to the foregoing...
During saving cxr. file from VFB don't exist option for change saving Gamma settings, as in regular saving menu of 3dmax, So it is not known with what Gamma settings cxr. was saving////
may be needed option for Controlling Gamma saving setting in File saving menu for Corona cxr. files:))
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-19, 16:42:38
Here is how to set up gamma in newer versions of Max (scroll down to the very bottom):
https://coronarenderer.freshdesk.com/support/solutions/articles/5000515647

A big problem is--- "Automatically"---- not working in some cases:))
Title: Re: Corona image editor saved images gamma
Post by: JoeVallard on 2017-06-20, 00:31:59
Hi, please, could you upload the CXR image so I can inspect it? Use our private uploader for that: https://corona-renderer.com/upload/

The save button saves EXR, PNG, BMP, or JPEG files with tone mapping (current element only), and CXR files with just tone mapping settings inside to be able to modify it in CIE any time later (all elements). The pixel data itself are not affected by saving into the CXR format.

Uploaded an example CXR that was having the issue that i posted about. I checked my gamma settings and the ini shows exactly what was posted for recommended.
Title: Re: Corona image editor saved images gamma
Post by: TomG on 2017-06-20, 21:05:53
Been doing some testing on various issues, using the CXR uploaded by Jtveclipse12, here are my results so far:

- Is tone mapping done in the CIE saved to the various file formats?
It is for me, tone mapping done in the CIE definitely shows in the saved images in all formats.

- Why does the EXR look different?
What are you using to load the EXR into Photoshop? In my tests I have used EXR-IO. I do see a slight increase in contrast in Photoshop compared to the CIE (if I screen grab both and overlay them). I also opened the EXR in Qt4Image, and I see that it matches PS. If I open the saved EXR in the CIE, it looks the same as the original CXR looked (that is, "less contrasty" than the EXR opened in PS or Q4T). 32 bit EXRs can be handled a bit differently by different applications. We'll keep testing - let me know what you used in PS to open it.

- Why do EXRs saved from the CIE not open in After Effects?
It opened for me. Could a sample "problem" EXR be shared with us?

- Why does the background image change in intensity?
When the CIE saved the EXR, it premultiplies the alpha. This is what the standard for EXRs says - however, my understanding is that almost no other software follows that standard.

- Saving to PNG from the CIE
I have noticed one new thing here while testing. After Denoising in the CIE, if Blend is greater than 0.0, the transparency in the PNG is 254,254,254 for solid, and not 255,255,255 (in PS, can extract this info by Layer -> Layer Mask -> From Transparency, then turn off the RGB and view just the Layer Mask in the Channels, then use the colour inspector on the "solid" parts).

This doesn't happen if no Denoising is done in the CIE (save without denoising, or load a CXR that was Denoised in the VFB), nor does it happen from the VFB. We'll investigate further. The upshot there is that darker areas in a PNG may look a little less dark in Photoshop, as it is displaying a small portion of the empty checkerboard behind it.

Counteracting for that though, the PNG from the CIE is the same as the JPG from the CIE, and both are the same as how the image looks in the CIE. So only EXRs loaded into external applications show a slight increase in contrast.

- Handy hint!
If you post comparison images, could you post them as separate images please? It allows easy overlaying of each one and then flicking layers on and off to make differences more noticeable :) Thanks!

More info as we do more research, and any feedback, tests and input welcome too! Thanks!
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-20, 23:28:53
Basically everything is fine, with correct setup scene in 3dmax /input-output Gamma settings/
I open in PS three versions saved to regular exr. file from CIE and it's the same//// (https://forum.corona-renderer.com/index.php?action=dlattach;topic=16497.0;attach=66329;image)

But exist problem with Alpha channel///
If i open exr. file saving from CIE Beauty as Alpha channel, not transparent, i get this problem:
(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16497.0;attach=66331;image)


------------------------------------------------------------------------------
It should be taken into account that with exr. file saving from CIE Lightmix always OKAY///
-----------------------------------------------------------------------------(https://forum.corona-renderer.com/index.php?action=dlattach;topic=16497.0;attach=66335;image)
Title: Re: Corona image editor saved images gamma
Post by: JoeVallard on 2017-06-21, 05:34:42
Open CIE
Load CXR
Apply, Denoise, Apply Tone Mapping, and Add Bloom and Glare.
Save as "Regular EXR"
Open Photoshop
Select EXR
Load alpha as Alpha Channel

The exr is saving the post processing info, I just thought it wasn't previously because the scene just looked different, which looks like its cause by the Background HDRI issue.

I did end up doing a blank render in Max and saving a PNG with Alpha unchecked. Now PNGs match CIE image exactly, however for some odd reason the next render I tried, the png saving settings were randomly change. So I had to save another blank PNG in Max again.

I tried loading the EXR i saved from CIE, back into CIE and the background is still dark. However I loaded the EXR into Max as a bitmap, and it correct.
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-21, 10:40:36
One TIP for CIE behavior...
Now CIE not correct for loading POST data settings from cxr. file by default /not only LUT settings, There is a suspicion that this applies to all settings in POST tab of VFB---I also found a problem with the filter sharpening/blurring ////
for full assurance that's all correct, exist possibility to save POST data to Corona Configuration file /conf./ from VFB and than loading them to CIE post data////
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-21, 11:02:10
Open CIE
Load CXR
Apply, Denoise, Apply Tone Mapping, and Add Bloom and Glare.
Save as "Regular EXR"
Open Photoshop
Select EXR
Load alpha as Alpha Channel

The exr is saving the post processing info, I just thought it wasn't previously because the scene just looked different, which looks like its cause by the Background HDRI issue.

I did end up doing a blank render in Max and saving a PNG with Alpha unchecked. Now PNGs match CIE image exactly, however for some odd reason the next render I tried, the png saving settings were randomly change. So I had to save another blank PNG in Max again.

I tried loading the EXR i saved from CIE, back into CIE and the background is still dark. However I loaded the EXR into Max as a bitmap, and it correct.

A Problem i think that CIE not correct saving exr. Alpha data, because even loading exr. file in PS with option /NOT TRANSPARENT--ONLY Alpha mask/ this still having TRANSPARENT on Alpha
channel///
For full controlled saving process i propose to make something like 3dmax saving tab for exr. type files///
In this case exist option to saving exr. files without ALPHA channel at all, only RGB data//
Also making saving configuration tabs for all other types of bitmap files /JPEG,TIFF,BMP,PNG/ for controlling Compression,Channels and etc. parameters during saving process///
Which exist in each
normal application for Image Reduction--- include Viewers:)))
Title: Re: Corona image editor saved images gamma
Post by: maru on 2017-06-21, 11:53:05
I think this thread is getting a bit chaotic. It would be great if you guys could report only the issues you have encountered in your posts, for example:
-EXR opens darker in Photoshop than in CIE
-Additional screenshots/files demonstrating the issue
And that would be the only content of your post.
That way it would be much easier for our developers to deal with the reports, and eventually provide with answers or solve the bugs.

Side not: I am using a free EXR-IO plugin to load EXRs in PS and I think it's really great, plus it has tutorials: http://www.exr-io.com/learning/
It also gets rid of that confusing "alpha channel as alpha" PS dialog.
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-21, 12:59:49
I think this thread is getting a bit chaotic. It would be great if you guys could report only the issues you have encountered in your posts, for example:
-EXR opens darker in Photoshop than in CIE
-Additional screenshots/files demonstrating the issue
And that would be the only content of your post.
That way it would be much easier for our developers to deal with the reports, and eventually provide with answers or solve the bugs.

Side not: I am using a free EXR-IO plugin to load EXRs in PS and I think it's really great, plus it has tutorials: http://www.exr-io.com/learning/
It also gets rid of that confusing "alpha channel as alpha" PS dialog.

Even with this Plugin i get completely same result:)
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-23, 14:21:43
A Problem i think that CIE not correct saving exr. Alpha data, because even loading exr. file in PS with option /NOT TRANSPARENT--ONLY Alpha mask/ this still having TRANSPARENT on Alpha
channel///
For full controlled saving process i propose to make something like 3dmax saving tab for exr. type files///
In this case exist option to saving exr. files without ALPHA channel at all, only RGB data//
Also making saving configuration tabs for all other types of bitmap files /JPEG,TIFF,BMP,PNG/ for controlling Compression,Channels and etc. parameters during saving process///
Which exist in each
normal application for Image Reduction--- include Viewers:)))

Yes, it is one of known feature requests and it is planned to be done.
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-23, 14:36:33
Thank you all for your posts. It took some time to dig in.

I have made a fix that should solve at least some of the alpha/transparency issues. It is being reviewed now and will be hopefully merged into next daily build. It would be great if you will be able to test the fix as it gets released. I will keep you informed in here.

I have still no idea, why display in CIE/VFB seems a little bit less contrast than EXR loaded to PS. So stay tuned!
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-23, 14:59:13
One TIP for CIE behavior...
Now CIE not correct for loading POST data settings from cxr. file by default /not only LUT settings, There is a suspicion that this applies to all settings in POST tab of VFB---I also found a problem with the filter sharpening/blurring ////
for full assurance that's all correct, exist possibility to save POST data to Corona Configuration file /conf./ from VFB and than loading them to CIE post data////
Hi, are you referring to the last daily build (2017-06-22)? If yes, could you please share a CXR that is not being loaded properly? Please use the private uploader for that: https://corona-renderer.com/upload/. Thank you.
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-23, 17:45:49
One TIP for CIE behavior...
Now CIE not correct for loading POST data settings from cxr. file by default /not only LUT settings, There is a suspicion that this applies to all settings in POST tab of VFB---I also found a problem with the filter sharpening/blurring ////
for full assurance that's all correct, exist possibility to save POST data to Corona Configuration file /conf./ from VFB and than loading them to CIE post data////
Hi, are you referring to the last daily build (2017-06-22)? If yes, could you please share a CXR that is not being loaded properly? Pleas use the private uploader for that: https://corona-renderer.com/upload/. Thank you.

This is was old post for Previous version's, BEFORE last Daily from 2017-06-22///
What happened in last Daily I have not yet tested:)
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-26, 14:01:44
This is was old post for Previous version's, BEFORE last Daily from 2017-06-22///
What happened in last Daily I have not yet tested:)
Please, try the latest daily then. There were fixed some bugs regarding loading postprocessing settings from CXR files ...
Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-06-26, 18:55:23
This is was old post for Previous version's, BEFORE last Daily from 2017-06-22///
What happened in last Daily I have not yet tested:)
Please, try the latest daily then. There were fixed some bugs regarding loading postprocessing settings from CXR files ...

Testing//
With loading post settings from VBF to CIE by default always OK :)
Thanks for work:)
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-26, 19:09:36
Testing//
With loading post settings from VBF to CIE by default always OK :)
Thanks for work:)

Great. :-) Thank you too.
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-29, 18:54:54
Thank you all for your posts. It took some time to dig in.

I have made a fix that should solve at least some of the alpha/transparency issues. It is being reviewed now and will be hopefully merged into next daily build. It would be great if you will be able to test the fix as it gets released. I will keep you informed in here.

I have still no idea, why display in CIE/VFB seems a little bit less contrast than EXR loaded to PS. So stay tuned!

Hi again, new daily is out (2017-06-29) and the fix is there. Please, could you try it whether it fixes your issuses? Thank you.
Title: Re: Corona image editor saved images gamma
Post by: James on 2017-06-30, 11:11:21
The problem I'm having is:

-Save CEXR from VFB.
-Open in CIE - all looks the same as in VFB (except Masking ID - see end*)
-Save from CIE to regular exrs
-Open regular exrs in photoshop with ProExr in photoshop
-Exposure is much higher in photoshop for Beauty - all other elements seem the same as in CIE
-Using an 'exposure' layer set to -1 corrects the exposure exactly when in 32bits. Then have to flatten to new layer and continue working as normal


*Also CIE applies the tone mapping to the Masking_ID element - really annoying! Cant imagine why anyone would want that? never had that happen in the VFB I don't think.

Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-06-30, 18:56:11
The problem I'm having is:

-Save CEXR from VFB.
-Open in CIE - all looks the same as in VFB (except Masking ID - see end*)
-Save from CIE to regular exrs
-Open regular exrs in photoshop with ProExr in photoshop
-Exposure is much higher in photoshop for Beauty - all other elements seem the same as in CIE
-Using an 'exposure' layer set to -1 corrects the exposure exactly when in 32bits. Then have to flatten to new layer and continue working as normal
Are you using the latest daily build from 29th of June? If not, try that please because it could be fixed there. If the latest build behaves the same, could you please upload the CXR file? Use the private uploader: https://corona-renderer.com/upload/. Thank you.

*Also CIE applies the tone mapping to the Masking_ID element - really annoying! Cant imagine why anyone would want that? never had that happen in the VFB I don't think.
Yes, it is a known limitation of the editor. It is planned to be handled properly in 1.7.
Title: Re: Corona image editor saved images gamma
Post by: mike288 on 2017-07-03, 15:27:47
Hi,

to be consistent with 3ds Max and Cinema 4D we have decided to no longer premultiply RGB channels by alpha while saving EXRs in Corona Image Editor, Corona Standalone, and in VFB of Corona for Cinema4D. This should avoid the above reported "edge/window/etc. darkening while saving into EXR" issues.

This change does not affect the CXR format. The change will be probably incorporated into next daily build.

(The premultiplication is actually required by the EXR standard and we were just following it. But it has lead to misunderstandings because 3ds Max nor Cinema 4D do not do it, which is wrong, but expected by many users and other software.)

Title: Re: Corona image editor saved images gamma
Post by: denisgo22 on 2017-07-03, 18:22:09
Hi,

to be consistent with 3ds Max and Cinema 4D we have decided to no longer premultiply RGB channels by alpha while saving EXRs in Corona Image Editor, Corona Standalone, and in VFB of Corona for Cinema4D. This should avoid the above reported "edge/window/etc. darkening while saving into EXR" issues.

This change does not affect the CXR format. The change will be probably incorporated into next daily build.

(The premultiplication is actually required by the EXR standard and we were just following it. But it has lead to misunderstandings because 3ds Max nor Cinema 4D do not do it, which is wrong, but expected by many users and other software.)

Beautiful news.
Thanks/////