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Colorcasts on B&W 16mm, Media Encoder issue?
Hey Everyone,
I am really stumped by this one. I am working with FCP6 and Apple Pro Res HQ scans of 16mm B&W footage. I am trying to encode a self-contained .mov file (direct from FCP) in Adobe Media Encoder CC (for Blu-ray) and then burn to Blu-ray with Encore CS6.
I burned the first test Blu-ray last night and when I played it back on my Blu-ray player/TV, I was stunned by the fidelity and definition of the otherwise thick/complicated 16mm grain structure, even via what was only a 6GB .m4v render (compressed from 33.5GB .mov). Everything was perfect…EXCEPT…I got these horrible “colorcasts” of red, blue, green, magenta, across the footage. Particularly in the last shot of the drain pipe (see example clips 14 seconds long):
Original: https://vimeo.com/97456916 (pass: “original”)
Blu-ray: https://vimeo.com/97453674 (pass: “colorcast”)***
Obviously the footage does not look this in either FCP6 or .mov in QT7. I just double checked and the colorcasts ARE visible when playing back the ME converted .m4v in Encore. So I am assuming this is a Media Encoder issue. Here are the settings I used:
I suppose it could also be a setting in FCP6 that is tagging gamma/color incorrectly and confusing ME…?
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Considering how long is has taken me to get satisfactory web compression results from 16mm footage in the past, I feel like I just hit a grand slam in the bottom of the 9th with the playback fidelity of the first test Blu-ray. The motion and definition are phenomenal, I mean we are talking Criterion quality–without X.264 or Blu Code–(even with all the modern “overcompensation” crap turned off on my TV). I AM SO SO CLOSE TO RENDERING/BURNING A PERFECT BLU-RAY IF I CAN JUST FIGURE THIS COLOR THING OUT!
Got a deadline for Friday to get this into the hands of a couple of prominent filmmakers.
Any help or ideas that anyone can provide will be most appreciated.
Thank so much!
Alec
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MAC PRO // OSX 10.7.5 // 2 x 2.66Gmz 6-Core Intel Xeon // 32 GB 1333 MHz DDR3 -
12 Replies
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there might be a color sub-carrier still attached to your film. try applying the color corrector to the footage and bring the chroma down to zero.
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Jerry,
Which program are you referring to when you say apply “the color corrector”?
At what point would the “color sub-carrier” have been applied since it is native B&W…in the telecine process? Is there a way to remove said sub-carrier without having to manipulate things in ME? I’d really like avoid re-encoding if possible.
Thanks much for getting back.
-Alec
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I watched those clips side by side on my HP Dreamcolor display and I’m not noticing any huge color differences here. There will be some minor changes when you are transcoding between formats.
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Tero, I watched the colorcast video 3 times before I realized what I was seeing – on the vertical shot at the end, the right side of the frame alternates between green and magenta. It’s subtle, but there.
I would second the motion to add a BW filter before exporting, hope that helps. Even though the source is black and white, the video file is still “color”, so best to “kill” that color in the image before re-encoding.
Thanks
Jeff Pulera
Safe Harbor Computers -
when color broadcasting came about….if one was broadcasting a black and white movie you would have to turn off the color sub carrier in the film chain otherwise you would get a faint red to blue to green color cycling on home TV’s. I remember having to do that back in the 70’s. you could kill the color using the color corrector on some clips and see if that is the issue. good lock.
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Jeff,
Yeah I guess all digital is technically “color”. Never run into a problem like this so I’ve never actually thought about that. It is a bit harder to see on Vimeo, like I said, it came and went throughout the whole of the film, but that last shot of the drain pipe is the biggest offender. I don’t have a Dreamcolor monitor but when you work with “real” BW as much as I have, I suppose you don’t need one for these things become glaring problems. Glad you were able to see it.
I applied Color Corrector (3 Way) in FCP and brought both the Saturation and the Chroma Center to 0, but I’ve run into a burning error a couple times here with my Blu-ray burner. I will get back here as soon as I have results…(think I am getting really close).
-Alec
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[jerry wise] “when color broadcasting came about….if one was broadcasting a black and white movie you would have to turn off the color sub carrier in the film chain otherwise you would get a faint red to blue to green color cycling on home TV’s. I remember having to do that back in the 70’s. you could kill the color using the color corrector on some clips and see if that is the issue. good lock.”
Oh wow that is really interesting.
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Okay so this is fascinating…
I added the 3-Way Color Corrector to the entire film with Saturation/Chroma Center at 0 > saved .mov self-contained > converted to .m4v (Blu-ray) in AME with the same settings as above > Burned to disc in Encore…and guess what? THE COLOR IS STILL THERE AND STILL JUST AS BAD.
I suppose this means that AME is introducing some color information…??? WHY!?!?!
I just went back and looked at the .m4v in Encore and in the playback, even as “demo-quality” as the playback is, I can still see the colorcasts. Suppose I should’ve checked that before I burned.
Any ideas?
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well crap…I thought that might have been the issue.
is there a “filter” setting on AME.? maybe there is a Black & White filter on AME. -
Not that I am aware of. I have looked high and low.
I am considering downloading Compressor 4 and trying an export out of there. I have Comp 3 but I imagine 4 has more up-to-date Blu-ray settings >>> i.e. .m4v as opposed to mpeg2 export options like AME?
This sound sane to anyone?
I guess it is worth a test, at least to single out if it is Encore or Media Encoder’s fault. I doubt it is Encore but at this point I will try anything.
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