CF vs. Avid DNx175 10bit vs. Native 7d footage

[Brian Luce]

Here are 3 un-CC'd frame grabs from some test footage.
The Avid was transcoded w/mpeg streamclip and wrapped as MOV.

Pulled from Vegas 9.0c timeline.
On a 24" Dell 1920x1080 display, the native 7d footage always looks a little sharper and has better color.

Why should I stay with Vegas when other NLE's like Edius apparently handle these files natively?

[Perrone Ford]

I don't know that the native footage looks sharper in these grabs, but it does look like you got a gamma shift. I don't know about the CF conversion, but what settings did you use in Mpeg Streamcllip for the Avid one?

[Cliff Etzel]

Just because you can edit files that are compressed natively doesn't mean you should.

Transcode them to a file format that is less CPU intensive and can handle being rendered and added back to the timeline accordingly without loss in image quality...

[Brian Luce]

Originally Posted by Perrone Ford

I don't know that the native footage looks sharper in these grabs, but it does look like you got a gamma shift. I don't know about the CF conversion, but what settings did you use in Mpeg Streamcllip for the Avid one?

Export to Quicktime
Avid DNxHD>Options button>Color levels RGB>Select 1080/24p DNxHD 175 10bit>quality 100%>Uncheck Interlaced Scaling>Select 1920x1080 unscaled>"Make Movie"

The difference is more pronounced on my Dell, though not huge, it really looks like the Avid and CF take a sharpness and color hit.

I downloaded Edius trial btw, and native files play not so good, but you can render them quickly and that transcodes them to HQ which is a Grass Valley version of CF.

[Perrone Ford]

Originally Posted by Brian Luce

Export to Quicktime
Avid DNxHD>Options button>Color levels RGB>Select 1080/24p DNxHD 175 10bit>quality 100%>Uncheck Interlaced Scaling>Select 1920x1080 unscaled>"Make Movie"

Yep, that sounds right.

Originally Posted by Brian Luce

The difference is more pronounced on my Dell, though not huge, it really looks like the Avid and CF take a sharpness and color hit.

Could it be that the Avid and CF codecs are actually bringing the image into compliance with could actually be broadcast, whereas the 7D is happy to record images that could never be broadcast? What do the native and transcoded files look like on the scope?

Originally Posted by Brian Luce

I downloaded Edius trial btw, and native files play not so good, but you can render them quickly and that transcodes them to HQ which is a Grass Valley version of CF.

Saying that CanopusHQ is the Grass Valley version of CF is implying some things that aren't true. CanopusHQ has a LOT more in common with DNxHD than Cineform.

[Pete Bauer]

Originally Posted by Perrone Ford

Could it be that the Avid and CF codecs are actually bringing the image into compliance with could actually be broadcast, whereas the 7D is happy to record images that could never be broadcast?

I don't use either Avid or Vegas so not going to get too far into this discussion. I did want to add, however, that IMO reducing the color to broadcast should be the prerogative of the editor (as in the person using the software) rather than automatically done by the NLE. There are other options for final use than broadcast, so I would think NLEs don't (or shouldn't, anyway) assume that purpose for the encode. Along those lines, Cineform pride themselves on maintaining good color and gradation and have posted in times past about utilizing super-whites.

Otherwise, sorry I can't be of much help with the color shifting issues here.

[Perrone Ford]

Originally Posted by Pete Bauer

I don't use either Avid or Vegas so not going to get too far into this discussion. I did want to add, however, that IMO reducing the color to broadcast should be the prerogative of the editor (as in the person using the software) rather than automatically done by the NLE. There are other options for final use than broadcast, so I would think NLEs don't (or shouldn't, anyway) assume that purpose for the encode. Along those lines, Cineform pride themselves on maintaining good color and gradation and have posted in times past about utilizing super-whites.

Otherwise, sorry I can't be of much help with the color shifting issues here.

Pete, I don't disagree. However, please be aware that at least with the case of the DNxHD conversion here, this is not being done inside an NLE. The conversion is being done in third party freeware. I should also note that Avid is VERY well regarded in the world of feature film, and the DNxHD codec was built with that audience in mind.

I will also note that having done DNxHD conversion both inside Vegas and in Avid MC, that the superwhites and blacks were preserved, and I experienced no color degreadation as shown to me on the scopes. I've done those tests with footage from numerous cameras including the Canon 5D.