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  1. I was curious about some of your views on the pic below. The official dvd for this film is in the middle and they did a nasty job of remastering it (way too dark for most of the film). I was playing around with auto levels in Premiere (as well as the third party made plug in for Sony Vegas)

    I am at a loss because both really bring the pic out so you can actually now see what is going on. I am partial to the Vegas version because the shot in question is supposed to be in a dark room and seems to be a nice mix. However the Premiere version clearly shows they probably shot the film in the light and artificially added the darkness afterward.

    Just wanted some other input before I start re-encoding and fixing this video



    for a much larger version, copy/paste the link below
    http://i40.tinypic.com/1z1hcpc.jpg
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  2. Member edDV's Avatar
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    Normal procedure is to make judgements from a calibrated TV monitor. Optimization is different for a computer monitor.

    A properly adjusted DVD will look dark on a computer monitor (different gamma) unless a gamma correcting software player is used.

    Auto correction is an approximation. The scene you show lacks any white reference so the auto algorithm must guess. The picture on the left shows the auto correction assumed the brightest luminance was white. That guess is too bright. The Vegas plug-in roughly doubled the wall luminance vs the original but one can't tell if this is correct unless viewed on a TV. Added to all that is the director's vision. Sometimes they like a dark look, other times darkness hides flaws.

    Click image for larger version

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  3. Thank you EdDV for your useful information.
    For this particular film (the Prowler), the vhs tape and tv prints were always muddled and hard to see in some scenes. The Blue Underground dvd that was released is a huge improvement, but like the tape, still hard to see many details in the darker scenes. Viewing this on a regular tv first I took notice and had thought the transfer for this film was overall too dark (I do not think the director wanted it this dark, then again you never know). I did some searching and noticed some other people who have this edition thought this as well. I then went in (more of playing around) with it on the PC. I am aware dvds play darker on the PC monitor and I apologize for not stating that I was viewing it on a regular tv first. I took some snap shots from the disc and put them in photoshop. Out of curiosity I used the auto levels and was taken back by the huge difference it was showing me. Clearly in some shots yes it was way too bright and exposed the fact that they probably shot the film with the lights on and added the effect to make them appear as if it was night afterwards. In some other regular daytime shots it jumped up the overall quality detail of the image and really brought the picture to life (so to speak).
    It was then that I wanted to see what it would do if I had let that auto level option run through the whole film. I am aware of it's side effects (like creating a bit of color flicker as some scenes play out), but it would be an interesting experiment.
    I later then noticed how both editing apps used different auto level options (which is what you pointed out and clearly gave much better info on) upon some test clips.

    For arguments sake they are doing a blu-ray of this film in the US (studio canal did one overseas which supposedly has a bit more clear picture), but for my own sake I wanted to see what I could do with the current dvd itself. I am leaning more towards what Vegas was producing, but I was curious as to what some others would say or give advice with
    Last edited by mazinz; 10th May 2010 at 03:20. Reason: typing
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  4. Member edDV's Avatar
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    When the pro colorist corrects an old film, they work scene by scene. The tools (usually a Da Vinci) work separately on low, mid and high tones but they are using 10 to 16 bit per component digital film transfers instead of DVD's 8bits per component. 8 bits results in serious quantization (stepping) errors when large adjustments are made. For this reason, gross VHS analog levels errors should be adjusted before A/D conversion.

    http://en.wikipedia.org/wiki/Da_Vinci_Systems
    Last edited by edDV; 10th May 2010 at 05:13.
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  5. Member 2Bdecided's Avatar
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    Originally Posted by edDV View Post
    8 bits results in serious quantization (stepping) errors when large adjustments are made. For this reason, gross VHS analog levels errors should be adjusted before A/D conversion.
    If you're going to denoise in software, it really doesn't matter for VHS. Fix the levels in software, then remove the noise. Result = no visible quantisation steps, because the VHS noise acts as/like dither.

    Cheers,
    David.
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  6. [QUOTE]=edDV;1985407]When the pro colorist corrects an old film, they work scene by scene. The tools (usually a Da Vinci) work separately on low, mid and high tones but they are using 10 to 16 bit per component digital film transfers instead of DVD's 8bits per component. 8 bits results in serious quantization (stepping) errors when large adjustments are made. For this reason, gross VHS analog levels errors should be adjusted before A/D conversion.

    http://en.wikipedia.org/wiki/Da_Vinci_Systems[/QUOTE]

    Thanks again for that info. In this case obviously that would be over stepping it a bit (I can see if this was a film I shot or had the original negative masters to), but for myself, it was just something to play around with. Still I learned more than I knew before so the posting was worth it
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  7. Member edDV's Avatar
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    Same principles are used in Premiere or Vegas color correction. Only the source quality differs.
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