View Full Version : 32-bit HDR in after effects
01 January 2010, 04:22 PM
I'm wondering why this HDR file I created reads as "properly" exposed in Photoshop and in my finder window (Mac), But it comes out dark in after effects.
I suppose I am actually seeing it correctly in after effects? As it is a linear file? And it is being color managed in Photoshop and then the finder?
I messed around with color management both in Photoshop and in after effects and was unable to make the result consistent between both programs.
Any insight would be much appreciated.
01 January 2010, 04:48 PM
As it is a linear file?
No. It's the other way around: It's not linear, but AE linearizes it. Check your footage interpretation to avoid this behavior.
01 January 2010, 01:51 AM
Oh? I was under the impression that HDR files were "linear". Just to give you a bit more detail the HDR was created from unedited raw files.
01 January 2010, 09:25 AM
Oh? I was under the impression that HDR files were "linear".
Huh? Why should they? HDR/ EXR files can be Gamma biased just like any other image file. Sorry to burst your bubble, but HDR != (not equal) linear color. It still depends a lot on how the file was created. RAW files are not full HDR to begin with, anyway, so you already skew the color info by blowing them up to float. Not to speak of tonemapping and other adjustments, let alone multi-exposure merges...
01 January 2010, 02:44 AM
ouch, consider my bubble bursted... OK HDRs are not necessarily linear. But what about an hdr created from raw files, bracketed exposures of converted directly from RAW.
01 January 2010, 07:04 AM
I think you are getting to crazy about the specifics. There can never be such a thing as a direct RAW to HDR conversion. Yes, you may be able to retain the value ranges, but they may not necessarily produce visible data. That's the whole point why RAW files need to be "developed" - you compress/ expand and offset those ranges to make sense in relation to the Gamma of the viewing device. In conclusion, this merely means that what you define as linear Gamma is the process of setting black and white points and eliminating the response curves of the viewing device and the source file by applying the inverse. If you will, you are pushing the values into specific ranges, making sure they are between 0 and 1 and have a neutral midpoint at 0.5. That's all there is to it and that's why AE auto-adjusts files that do not meet this criteria, if you want it to. Beyond that, "linear" often is merely a case of tagging the meta data, so sometimes it becomes a matter of what you want to be "linear". The result is pretty much the same, though. based on retagged Gamma info, the colors will still adjust.
01 January 2010, 07:04 AM
This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.