Jump to content

Color shift/compression artifacts in video rendering of S8 scan?


Dan Peterson

Recommended Posts

Hi All,

I can't seem to get to the bottom of these issues. I've posed the question(s) on the forum for Sony Vegas, but no answers were really helpful or solved my problem...

Also, I would truly appreciate any advice on how to take a good scan of Super 8 film and get it on to YouTube or Vimeo with accurate and faithful color representation, no compression artifacts, and best HD quality.

Ok, here goes:
I've shot both Tri-X 7266 and Vision 50D with my Nikon R8. I've had the Tri-x scanned at two separate facilites (one west coast, one east coast). The Vision 50D was scanned at the west coast facility. All scans were done at 2k to the Apple Pro Res 422 .mov format.

This .mov format can be handled by Sony Vegas Pro (version 13). However, when ever I render to any .mp4 file type (different resolutions, frameserving to Handbrake, etc.) the reds shift from fire engine red to a cranberry red.

Look at the image in my Dropbox account below. The upper window is the Vegas timeline preview, where the colors are correct after tweaking brightness/contrast and color balance (the scans were "flat" scans). (You will also see that the Computer RGB to Studio RGB fx is disabled in Vegas. Typically you use that when sending a file to YouTube, but just ignore that, since the color shift is very apparent whether the render is done with or without that effect.) The lower window is the .mp4 file being played back on the same (calibrated) monitor. Notice the big color difference in the red truck.

https://www.dropbox.com/s/1mdsudkgyo2d1ps/Vision_50D_colors.jpg?dl=0

Any ideas if the issue arises because I'm using an Apple Pro Res PC on a Windows PC? I've read forum threads elsewhere where people claim that renders on Apple computers (with Final Cut Pro) keep colors true without a hassle.

Another issue is that no matter what my workflow or render type (frameserving from Vegas, Avisynth, Handbrake, etc.), the grain in the Tri-X scan is really just mangled and the compression artifacts are just unacceptable. I finally just pushed the original scan file to YouTube (which it accepts, btw), but it's no where close to the beautiful projected image. Here is that scan:

 

https://youtu.be/JWfcbewW1O4

Any advice here? How do you get high quality, true-color scans on YouTube or Vimeo? What is your workflow? Do you ask the scanner facility to scan to a different codec? I feel like I'm missing something....

Thank you for any help!

Edited by Dan Peterson
Link to comment
Share on other sites

  • Premium Member

It's complicated.

 

The problem isn't anything to do with the source files or the fact it was shot on film, nor is it due to any concern of operating system. The colour issues are to do with the differences between studio and full swing, and/or colourspace conversion that's happening at some point in the whole chain of stuff. It's extremely difficult to diagnose these problems remotely, unfortunately, and I'm not an expert on Vegas. It should be possible to fix it with the right combination of settings, although that combination may be difficult to arrive at. An alarmingly large amount of software doesn't make it easy enough to do this and you have my sympathy; I can offer little else.

 

Grain is noise, and noise is hard to compress. Use the highest possible bitrate and the best possible encoder.

 

P

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...