Corona Image Editor issue

[hrvojezg00]

We have a problem with Corona Image 1.6 hf2. After making the postproduction in it, saved in exr, openes in photoshop unclamped (over highlighted). Is this a know issue?

[maru]

(already on support, I checked this and it seems everything is fine, but waiting for further info from Hrvoje)

[hrvojezg00]

Problem remains on 1.6 hf2 when using glare/bloom in CIE, waiting for final 1.7 to check if fixed.
Also, images saved as exr have black (AA?) frame around windows looking out towards background plane with applied photo. Doesn`t show when saved to jpg.

[mike288]

Problem remains on 1.6 hf2 when using glare/bloom in CIE, waiting for final 1.7 to check if fixed.
Also, images saved as exr have black (AA?) frame around windows looking out towards background plane with applied photo. Doesn`t show when saved to jpg.

Hi, the effect of "black frame" (or "darkening edges" in general) in EXR files saved by CIE is caused by alpha premultiplication which is something that standard for the OpenEXR format requires to do. 3ds Max (and almost no other software) does not follow the standard in this. That is why EXRs saved by Max (and others) don't introduce such "darkening". Saving to EXR format in VFB is being done by Max, not by Corona. CIE used to premultiply by alpha in 1.6.2 version. Even if it is wrong and goes against the standard, we have decided to stop doing it because this seems to be expected by users and also to be consistent with VFB. CIE in 1.7 daily builds already implements this change.

I still don't understand what is wrong with bloom and glare. Purpose if these effects is to add highlights. Please, could you better describe the issue? What is expected result and what result are you getting?

[hrvojezg00]

Thanks for the clarification!

We setup Bloom/Glare in CIE and it looks great, but saved as exr and opened in Photoshop, comes overexposed/over highlighted. I mean just the parts where B/G is.

[TomG]

Bear in mind that Photoshop does not work very well with EXRs - do you get the same problem opening with either an EXR plugin for Photoshop (EXR-IO is the one I use), or with another application that handles EXRs well (Nuke, Fusion, After Effects should all work)?

[hrvojezg00]

I will check that plugin, we work in PS mainly for post. Would the problem remain if there would be a way to save as 16bit exr?

[mike288]

I will check that plugin, we work in PS mainly for post. Would the problem remain if there would be a way to save as 16bit exr?

not sure ... could you make some screenshot (with both CIE and PS) where it can be seen, that the same image is overexposed? maybe, could you also upload your image via our private uploader (https://corona-renderer.com/upload) so we can inspect it?

[hrvojezg00]

Images sent to private uploader.

I will check that plugin, we work in PS mainly for post. Would the problem remain if there would be a way to save as 16bit exr?

not sure ... could you make some screenshot (with both CIE and PS) where it can be seen, that the same image is overexposed? maybe, could you also upload your image via our private uploader (https://corona-renderer.com/upload) so we can inspect it?

[mike288]

Images sent to private uploader.

Thank you. Please, could you also upload the input CXR for them? Just for debugging purposes. We are not gonna share it anywhere ...

[hrvojezg00]

Its originally 6k cxr 6.5 gb, so its a bit tricky to send it.

[TomG]

The private uploader page has a link at the bottom that allows files of up to 10GB to be uploaded using dropbox - https://corona-renderer.com/upload

Thanks!