[johnmeyer]

Fred,

I think it is wonderful that you are continuing to improve your transfer system and also improve the post-production techniques, including your script. Many people abandon these projects after their initial effort.

Since you are starting a new thread, and since you want to discuss possible areas for improvement in the script, let me make a few comments about the before/after video you posted. As you know, I have used your script, with a few variations of my own, for several years now. I mention this because what I am about to write below could be seen as negative, but I think you will understand that my intention is to be constructive, and to point out those areas that I still think need improvement.

1. Water. One of the problems in both the MDegrain and also RemoveDirt sections of the script is that they deconstruct waves, flowing water, and other similar "watery" structures. If you go to the 0:20 mark in your video and look at the middle upper part of the little waterfall (concentrate on the bright upper part of the middle section), not only is there a green shift, but there is a loss of a lot of subtle structure in the water, most notable in the whitest parts of the water. I have seen this so often that I no longer use your original script on any scenes that contain open or running water.

2. Blue Sky. I have pretty much given up using the color correction in your original script (the "coloryuv(autowhite=true)" setting), although once in awhile it does help correct color casts that I cannot correct any other way. If you look at the blue skies in the various scenes in the clip, you will see a definite turquoise (blue-green) shift. The original blue colors appear much closer to correct. There is also a shift towards green in some of the white highlights in all the scenes in the clip. I use the Spyder colorimeter to color calibrate my display, so I think I am viewing the colors correctly, although as most people know, color is extremely difficult to get right.

3. Gamma correction. It appears that you may have improved the gamma correction algorithms. The street scene taken from overhead (at about 0:14) has wonderful improvement in the shadows. I will be interested to know what you have done to get that improvement. As anyone who has transferred film knows, this is one of the toughest things to get to look good, especially if you use a stock video camera for capturing.

4. Clouds. This is actually probably the same issue as what I described with the water, but if you look at the clouds at the 0:24 mark, you will see that a lot of subtle structure and detail in the dark part of the clouds has disappeared. One of the issues here is grain removal. I have done a lot of noise reduction over the past ten years, and one thing I have noticed is that noise (and grain) impart a certain artificial sense of detail, even where none existed. Part of this is psychological, but part of it may be due to the fact that all these "dancing artifacts" do tend to form real details via their movement, and eliminating that movement reduces the details. Once again, the problem is most evident in "objects" that have very little fine structure or detail. On the other hand, objects with lots of detail -- like buildings, flowers, people's faces -- look spectacularly better after treatment with the script. The flowers at 0:28 look unbelievably good. Nice job!

5. Streets. This is similar to the water and clouds, but it happens so often in my film transfers that I have noted the problem many times. You'll see it in the scene starting around 1:09. At first, all most people will see is the remarkable improvement on the external structure around the building in the background. Good stuff! But then, if you start to look at the road in front of the car, you'll notice that almost all the detail and "depth" has been eliminated. It almost looks like what happens if you take a little water and smear it over a watercolor painting, blending all the details together.

The scene that follows, with the tops of the railway cars, shows both the positives and negatives: at times the details are improved, and at other times, especially on the tops of other cars, the details seem to be obscured. This scene actually may hold some clues as to how we might build a better script because the detail on the tops of most of the cars seems to have been improved, whereas the details on one or two seem to have been diminished.

6. Motion stabilization edge loss. The depan motion stabilization works exceedingly well. I own Mercalli and have written extensively about Deshaker, so I have had a lot of experience using these tools. You have done a great job discovering the right settings for Depan. However, one area of improvement would be to find a way to use Deshaker or some other tool that preserves the edges so that we don't lose so much of the frame due to the zooming needed to hide the moving black edges introduced by the motion stabilization. I have justified this because the motion stabilization, IMHO, is one of the two biggest improvements the script provides (the other being dirt removal), and because my capture systems (like yours) capture the entire frame of film (the gate has been removed) so all that is being discarded is the part of the film that probably would have never been seen during normal projection. Still, it is sad to see all this information discarded ...

So, in summary, the areas of improvement I would like to work on would include (more or less in order of importance):

1. Better color correction.
2. More natural (or less aggressive) grain removal that doesn't harm detail in water, roads, and clouds.
3. Better gamma correction (which you seem to have already achieved -- I just want to know how you did it!)
4. Deshaking that preserves borders.

I don't have any ideas for #1. I think #2 may mostly be a matter of finding better settings for the existing plugins. #3 you have already achieved, but I hope you can explain how you did it. And, #4 will probably mean incorporating Deshaker, something that may be more bother than it is worth, given the two-pass nature of the approach that program takes.