Red jumps out on SVHS

Caruso wrote on 5/15/2004, 4:39 AM
If I hook my Digi8 cam to my TV, the colors on my project are just beautiful - so, without knowing, I guess I'm not violating any broadcast standards - it looks great.

But, if I copy via SVHS hook-up (either from the Digi8 Cam or pass-through from my computer) to my SVHS deck, one character's red dress literally jumps out - it's too saturated, the red is bleeding around the edges, and black trim in the dress is blurred due to the oversaturation and bleeding of the red.

So, what would you suspect is wrong, and how would I go about toning down that color without muting the vivid colors in the rest of the piece.

Thanks.

Caruso

Comments

farss wrote on 5/15/2004, 4:54 AM
Even though you may have the levels within BC legal limits you can still run into problems just like this one. Red against black can be a problem. This isn't anything you've done wrong, just a limitation of the system. You could just ignore it but if you think it's going to be an issue then you need to turn the red down or else bring the black up to avoid the jump in level at the edges.
If there isn't any other reds in the shot you could use the color curves to reduce the gain on the red channel which will turn the offending reds down. By putting a few bumps in the curve you maybe be able to avoid upsetting any other reds elsewhere in the frame. If that doesn't cut it then you'll need to create a mask and just turn down the reds on the dress. Don't know the specifics of how to do that but I'd suggest first off all try pushing the reds up the use a min/max filter to generate a mask. Unless someone else has more experience you'll have to experiment a bit but I know it can be done.

Other tool to look into would be secondary color corrector.
johnmeyer wrote on 5/15/2004, 10:38 PM
Use Secondary Color corrector. I gave rather explicit instructions for a starting point in these threads:

Correct Red Blooming

How can I remove just red saturation?
Caruso wrote on 5/15/2004, 11:34 PM
Thanks, John. I'm going to print out your settings and give them a try. Here's one more follow-up question for you (the answer to which will be telling when I view the results after applying your settings - eight hours from now):

If the rendered file, printed to DV and played through a TV via S-video cable, looks fine, and only starts to jump out at me after being copied to VHS or SVHS tape, is this still a problem that can be overcome through secondary color correction?

I'm just wondering why everything looks so natural when I play the digital8 version of this piece, then, the red jumps out upon copying to VHS/SVHS.

Thanks again for your informative response.

Caruso
Caruso wrote on 5/16/2004, 2:06 AM
John:

Tested your settings and rendered just a portion of the offending footage.

No appreciable difference in the VHS copy.

I can see the effect through V5 Preview, using the split screen preview, but, after rendering a section of the piece and printing it to VHS tape, I see virtualy no difference - this gal's red dress jumps out at you.

I fiddled with my TV's picture settings, cutting the saturation a bit, and that makes the piece much less objectionable, IMO.

Doubt casual viewers will bother with changing settings on their TV.

I need to issue the piece, so, I guess I'll have to let this little detail go for now . . . but, I'm disappointed - wanted to solve the issue.

Caruso
farss wrote on 5/16/2004, 2:44 AM
If it looks OK on the TV off the D8 and not the VHS then you're probably right, no ones likely to fiddle with the TV just to accomodate your tape. I don't know what's in John's settings but you probably need to cut the red channel back a bit more. Rather than render the whole project out just try to work on the offending clip, render out a short section and PTT. Also you could make some generated media with say the same reds and blacks, have a look at the levels on the histogram. Then see how much you need to pull that back to stop the bleed. Possibly part of the problem is also that you're going from the D8 into the TV using S-Video but I'd imagine you're going from the VHS to the TV using composite..
You may be able to simulate the problem and hence work on it easier by going composite from the D8 to the TV rather than S-Video. If you can get it to show up on preview it'll be much easier to make adjustments.
Caruso wrote on 5/16/2004, 6:10 AM
Farss:
You're right about my VCR hook-up - well, no, you're not right, come to think of it, I'm using co-axial cable. My VCR (part of my sound system setup) is 20 some feet away from my TV. House was pre-wired during construction using coax - the state of the art at the time.

Your troubleshooting thought did cross my mind, however, so I printed a segment using composite cable instead of S-Video from the camcorder to the VCR.

No appreciable change in the red areas, although I could see some drop off of sharpness everywhere else.

For now, I'm tired of fiddling with this - need to finish the thing and move on.

Thanks for the suggestions. I'll revist this after I cool off a bit.

Caruso
johnmeyer wrote on 5/16/2004, 7:50 AM
In the Secondary color corrector, take the color saturation ALL the way down to nothing. The offending color should now look B&W. If you see any color at the edges, you will have to adjust the settings to make sure you are getting it all. Then, move the saturation control back up until you see a small amount of color. Print that to tape and see if if looks acceptable.

Make sure you use S-video cables to record the video on your deck. Use the best tapes possible. And most important, under no circumstances should you use the 6 hour tape speed -- it will dramatically worsen the red blooming problem.
HPV wrote on 5/16/2004, 11:39 AM
Svhs and vhs can't handle the DV color saturation. Reds will always be the worst. You can use the color correction filter and drop the saturation down.
I do this with a external tbc so I don't have to render a project twice.

Craig H.