5D MK II crush black issue?

[Yang Wen]

Is there a known issue of the videos from the 5D2 having crushed blacks? Every video I've seen exhibits this problem. Is there a workaround to it?

[Jon Fairhurst]

Yes, there is a workaround. It involves two steps:

1) Create a custom profile with low contrast, using the Picture Style Editor and load the profile into the camera.

2) Before bringing the MOV file into your editing system, process it to convert the 0-255 range video to 16-235. The easiest is to "re-wrap" the MOV file as an MP4. See this thread for details: http://www.dvinfo.net/conf/canon-eos...something.html

[David Moody]

I think if you edit with a Cineform intermediate you will avoid the issue.

[Jon Fairhurst]

Originally Posted by David Moody

I think if you edit with a Cineform intermediate you will avoid the issue.

It depends on how you generate the intermediate file. Before the machine can encode to Cineform, it must decode the MOV file. If the MOV decoder doesn't recognize the RGB 0-255 coding, then those levels will be lost in the translation.

Unless you are using Color, or some other app with a Quicktime Decoder that is known to deal with the 0-255 levels, I recommend, the rewrap method above - before creating your Cineform intermediates.

[Daniel Lipats]

Keep in mind that the .MP4 is not supported by all NLE.

Premiere will not load them, you will have to use one of the other methods well covered on this forum.

[Jon Fairhurst]

FWIW, Vegas supports the re-wrapped MP4 files.

[Yang Wen]

Is there data in the crushed blacks? Meaning if you lift the black level using the above workaround, will image information be brought out?

[Jon Fairhurst]

There is definitely data there. In some examples, the data recovered in the whites is stunning. One pic will have mushed white in the sky, while with recovery, you see blue sky and whispy clouds...

Here's a clear example:
http://www.dvinfo.net/conf/978000-post11.html

[Mike Calla]

I just downloaded the NeoHD trial. It definitely helped a lot - a few things and they are:
Note: As my reference I’m using the video2.mov sample from dpreview…the blue suit walking near the vegetable market clip:)

I did a straight conversion from the .mov file using HDlink to a Cineform, “high” setting .avi file.

- It brought back the details from the dark areas. You can see details in his blue suit now, and the awning over the vegetables now has a brownish quality rather than the deep blacks it had and I can see lots of detail in shadows now
- It did the same with the washed out white sky, I now have some detail in the clouds, there is more contrast and colour now

overall the colour seem less saturated and the footage handles colour correction quite well now.

I guess most people are getting these results so nothing special...

BTW my scopes show this for the Cineform clip - but in the audio world they have a saying: "trust your ears not your VU meters"

[Mark Palmer]

Looks good, but what's the Mac solution to getting back the detail in the blacks? I've tried Mpeg Streamclip with no success.

[Pat Reddy]

Just a side question. I've noticed that there is a lot of aliasing and/or moire visible in that video2 sample from dpreview. Is this typical for the 5D MKII?

Pat

[Aaron Palabyab]

I've been reading around here for a Premiere CS3-friendly fix to this.

I tried Didier Perrichon's fix (http://www.dvinfo.net/conf/canon-eos...4-problem.html) that involves using mpeg streamclip to convert the raw files (used "video2" from dpreview) to Avid DNxHD.

Tried to open it in Premiere CS3 - no dice. Crashes every time I try to view the video. BUT I tried checking it in After Effects CS3 and true enough, while the original file still exhibited clipping, the converted file had all these values back (i.e., levels histogram had no blanks). So I exported this clip from AE and voila, they worked in Premiere.

This has too many steps for my taste but for those who have both AE and Premiere, I guess it's a zero-cost alternative. Will have to do more tests though to see if rendering times will prove too onerous with longer clips.

[Yang Wen]

Okay I'm confused.. is the Crushed Black and blown whites an issue with the codec ? Or an issue of the default picture parameter of the 5D2? I was under impression that it has to do with codec incompatibility.. but then I saw the sticky in this forum with would suggest it is simply a picture parameter issue..

http://www.dvinfo.net/conf/canon-eos...ep-thread.html

Which is it?

[Derek Doublin]

I am also interested in a Mac solution for the crushed blacks. Anyone know of one?

[Jon Fairhurst]

Originally Posted by Yang Wen

Okay I'm confused.. is the Crushed Black and blown whites an issue with the codec ? Or an issue of the default picture parameter of the 5D2? I was under impression that it has to do with codec incompatibility.. but then I saw the sticky in this forum with would suggest it is simply a picture parameter issue..

http://www.dvinfo.net/conf/canon-eos...ep-thread.html

Which is it?

It's primarily a codec compatibility issue, but you can get even more dynamic range, if you lower the contrast in the picture profile. The standard profile has an S-curve, and by lowering the contrast, the S-curve is less aggressive. You can go even further by setting an inverse S-curve in your profile.

The bottom line is that you can shoot without crushing the blacks, but you have to take action to bring out the dark details. In fact, with the low light sensitivity of this camera, it can deliver a lot more dark detail than the competition, if you plan for it.