Horrible Liquid colour correction side effects
 

I am trying to warm up some talking heads of Africans people. Side effects from doing this include green patches on their faces, both as colour fringing and blotches, and grey vertical stripes, also, helpfully, in their faces. Non of this is present until colour correction is applied. Is this another of liquid's delightful bugs?

Shot on z1 in hdv, logged in sd.

s

Stuart,

What render/fuse codec are you using for your sequence? Are you using MPEG2 MP@HL, 2VUY HD, DVCPro50, or DV25, or DV ? And which color correction tool are you using, clipbased corrector, GPU, Commotion. There are different levels of quality for the different color correction tools.

Which color correction tool gives the best quality? (and which the worst?)

How does a new user know about this? Is it in the manual?

Stuart,

The Clip FX CC operates in 8 bit RGB while the others use YUV. However, if you're trying to color correct on a highly compressed file/timeline, (I'm making an assumption here) like DV 25 and using the Clip FX cc then I can see where you can possibly get banding. Other than that, I've never encountered this issue.

Jack, I've only been using Liquid for about 9 months and the manual has an extensive section on color correction and I'm still learning it. Each color corrector has different controls depending on whether you need just quick color balance, luminance or if you need gamma or all the way to secondary cc. So you pick the cc tool for the task at hand. I normally use the Clip FX because it is easy, handy and real-time.

Maybe it's an obvious question, but are you using a compatible version of Quicktime? Starting with 7.1.3, and continuing with the recent 7.1.5 update, Quicktime does not play well with Liquid, whether the source footage is QT or not. Versions 7.0.4 and 7.1 are reported to work as intended, though you'll have to juggle installations if you use other apps that depend on newer updates.

They don't seem to be available on Apple's site anymore, but you should be able to find them somewhere. Worse comes to worst, I can always email you the copies I've got.

Thanks Guys. I am just off out and the edit suite is off but the material is captured from HDV downsampled in the deck to DV, I think that the timeline is set to DV PAl- the default to be honest and the editor I am using is the one from the menu bar with the little paint palette and arrow logo.

David - are you saying that changing to a diffrent format for the timeline will solve the problem? (whihc seems to simple to my mind) If so which timeline format? And do you then need to change it back to output?

s

Stuart, It maybe too late for changing the timeline because you started out at digitize at DV. For best image results in HDV post workflow, the process I've used goes like this. Capture HDV. Edit HDV. Color correct HDV. Then fuse a new timeline, (copy the timeline and change) for downconversion/scaling in uncompressed YUV. Some people color correct the uncompressed timeline, but I've tried both and couldn't tell the difference.

Then output the uncompressed timeline to DVD or Betacam SP etc. I would stay away from posting and cc in DV altogether. If you must go to DV, do at the last stage by fusing from HDV after cc to DV. But color correct before you go to DV. I think this is even the common workflow for Final Cut Pro.

This is my best guess as to what is causing your problem.

Good luck.