Cineform r2cf and cf2dpx color profile handling

[Stepan Kment]

[perhaps David Newman, would You help, please?]
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Just downloaded trial of Neo4K and run into trouble. Not with Neo's performance, that's totally amazing and on our Core i7 it even transcodes r3d to cf avi reasonably fast. The problem is .. color management.

R2CF appears to convert r3d's to Cineform encoded AVI perfectly with ton of great options. I am missing color profile setting, though. And even can't tell, what resulting CF AVI is. And faq on CF web site has no information on this.

It seems AFX importer of R3Ds outputs HDTV Rec. 709 profile (can't be changed in any way, probably clips a bit as RED came with their REDspace). What CF AVI is however? Linear? Maybe - direct convert of CMOS response. Or log? Which? What does RED SDK return and how it is set in r2cf..

[Observation: 12 bits in CF 4:4:4 encoding mode should be just fine if r3d to linear 4:4:4 takes place - 12 bits is mysterium's A/D precision I believe. However, any log conversion means information losses in this case.]

Also, for seamless AFX integration, one would certainly need a ICC profile for these CF files. Expect some unknown luminance response curve and white at ??5000K??, which is said to be native Mysterium color temp. or anything that RED SDK renders out.
Anyone could help create this profile? ICC file is.. binary :crying: I bet everyone using CF AVI in AFX needs this - or always applies the same set of filters to each imported file to change the appearance manually, which is -well.. :yikes:

Much the same applies to CF2DPX utility. Seems to me there is no way to change anything there. It'd really help to allow for profile conversion there, eg. from .. linear CF to typical DPX, which is gamma 1.7 and PDlog 685 or 985 interval of RGB values.
[at least, there is a ICC profile for 5500K DCI and Kodak stock present in AFX, so one can directly export and let AFX do the conversion itself.]
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CF's soon to be released metadata editor maybe will solve most of the pain with both import and export, we'll simply set proper metadata on converted AVIs and that'd be it. However, that'd solve a problem with a need of specific import ICC profile; still we need to know what profile r2cf exports.

 

[Stepan Kment]

clarification to previous post..

clarification to previous post..

to clarify more - page 7 of this PDF from adobe:
http://www.adobe.com/devnet/aftereffects/articles/color_management_workflow/ae_color_mgmt_wkflow.pdf
explains, why ICC profile is needed. As a workaround, it may be OK to convert r3ds to Rec. 709 profile perhaps.. otherwise one is forced to correct every single file imported in AFX, gamma, color temp heavily. Again and again. Valid ICC profile certainly can't mean first light is done; it'd just mean initial view of files in the viewport would be much better than probably linear luma I see at the moment with all the washed colors etc.

I manged to read whole 60 pages of "CineForm Officially Supports Red One" thread in this forum, it is incredible chaos of posts added over maybe more than a year(!), versions of CF builds and Q+A. From that, it seems r2cf doesn't change luminance in any way, only reencodes with different codec, it embeds metadata from r3d file to CF avi and that's it. However, as I doubt I'll get files with usable metadata from camera, I'd rather simply set something average, ensure I don't loose any single bit of precision and import into floating point precision of AfterFX to handle the data.

Bad is new website of CF caused most specific hyperlinks one can find on reduser threads now fail .. really, anyone from Cineform, please..! I'd be glad to volunteer and write everything down here, nice 1-2-3 how-to with some help!

 

[Hans von Sonntag]

Hi Stepan,

I highly suggest that you either contact CineForm directly, or use under http://www.dvinfo.net//conf/forumdisplay.php?f=76 the specific CineForm forum.

Kind Regards,

Hans

 

[David Newman]

There is no color profile for any CineForm exporter, and that is the correct way to handle this. The data is basically RAW and all changes from RAW are under user control. Premiere Pro doesn't need ICC profiles form HDSDI feeds to calibrated monitors (same for AE.) You are making a simple issue too complicated. Yes you can calibrate a desktop display for color correction (HP dream color monitors are a nice way to go) but that happens after the decoder output not before. So that question has very litte with you source data.

All the cool information from the old (hard to find) website has moved to techblog.cineform.com.

 

[Stepan Kment]

thanks...

thanks...

OK, acknowledged. It seems one imports "something" in the project and has to do color tweaking really from scratch. As a reasonable starting point one can assign sources Rec.709 profile.

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I really can't imagine working in uncalibrated environment for any serious work. OK, for HD.. at least sRGB is pretty close match to HDTV, so it is reasonably safe to work in Premiere and even tweak colors. However, for film.. I don't think, when Digital cinema is 5900K, sRGB and HDTV 6500K, camera sources often as low as 3200K... Just try to play with available color profiles in AFX, each profile represents completely different look, not some slight change, the differences are dramatic - so don't expect any predictable output without hardware calibrated LCDs. The first thing operators of Lustre I worked with say is LUTs, LUTs. (even worse is each SW uses different LUT type, ICC, LUT, LOOKS.. and whatever else, of course mostly incompatible, as usual).

Btw - concerning recommended LCDs - I have HP LP2475w as a secondary monitor, much much cheaper than Eizo we use as a primary, still it has wider than AdobeRGB gamut and can be directly connected to RED via HDMI. That was a good choice, too, highly recommended for its price/performance.