I recently acquired and watched all the Jon Pertwee era Doctor Who episodes that have been restored to color through various processes. I thought this would be a good time to share my opinions on them.
To start with, Doctor Who had a major change following the departure of Patrick Troughton. It switched from about 48 episodes a season, to 26, went from black and white to color and most of the production team changed. Much of the same practices existed so even though all the Jon Pertwee episodes were converted for US viewing in color, the original video tape masters were wiped. Only a handful of episodes remain as the original PAL 2" video tape masters. Most of the rest that have existed in color were tapes returned to the BBC from the US market. I was fortunate to see virtually all these episodes in color in the early 80's.
But there are several big holes in what the BBC holds. While they have a black and white copy of every single Pertwee episode, they do not have ever episode in color. After a lot of hard work, they have been able to restore the original color to all but 2 individual episodes. The Mind of Evil episode 1 has no color data at present and Invasion of the Dinosaurs episode 1 is missing the blue color data. Other than that, they have all been restored using original color data and those two episodes have been restored using colorizing techniques and the color data from the other episodes.
The two techniques they have used to restore the color leave something to be desired when compared to even the NTSC copies. The first technique was to use inferior off-air US broadcast recordings and overlay the color on the black and white film copy (which has superior resolution). As the original recording was made according to the standards, it was a black and white layer and a color layer superimposed (so that black and white televisions could interpret the signal). This process was complicated by the warping of the image when converted from video to black and white film (the mechanics were to show the program on a television screen while filming it with a camera). The second method makes use of the detail of that filming process. For many of the episodes (except the two noted above), the detail on the film is such that the individual pixels on the television screen can be made out. This can then be converted to color data based on the red, green, and blue pixels and used to restore the image to color.
My critique comes in the inconsistencies that glare when viewing them. Don't get me wrong, seeing them in color is far superior to having to watch them in black and white. And knowing that the colors are original is magnificent, but the errors could be fixed to make this a much more enjoyable and seamless viewing experience.
One of the flaws relates to how the image was recorded. There are some issues with filming a television screen. You end up with some ghosting. It is especially bad when you have portions of the image that are very bright or very dark. Bright areas have a lighter halo around them and the dark areas can be too dark. This extends back to the first six seasons as well. But with the color, it causes a distortion in the colors.
The other major flaw is in color consistency and color ghosting. I must say that the color ghosting only is noticeable in the episodes restored from the off-air NTSC video tapes. In particular an abundance of magenta near darker flesh tones. The real problem is a frame to frame inconsistency. The two processes yield two slightly different results, but it is the same issue. There are color fluctuations that distract. Some ares need some of the colorization stabilization techniques. In particular I recall an orange curtain in the background that had unrealistic magenta stripes than flickered off and on and change position in the scene. In the other process (which I forgot to name as the Chrome Dot technique), some frames loose the color intensity in the middle of a scene. Usually when things move. Both of these issues could be solved by applying some of the colorizing software and some creative computer editing to create a more accurate and realistic color across all the frames. It is kind of bad when a completely colorized episodes (The Mind of Evil episode 1) looks better than the restored color.
But they have come a long way from the colorless versions I last saw. I am suitably impressed at what they have done, but they still have a way to go to get it to a final state. I think they have tried too hard to be faithful to the slightly flawed color in their source material at the expense of the final product. The whole point is to try to make these episodes look like they were never lost in the first place. They have come damn close. They have already tried to restore from the NTSC sources more than once and the current restoration is a vast improvement on the last, but they need another go at it. They need to further compensate for the flaws in their color sources and try to make these episodes look indistinguishable from those that exist as NTSC conversion masters or the original PAL masters.
Just considering the quality of image, I'd rate these restored episodes a three out of five. Just considering what they managed to do with what they had, I'd rate them a five. Just incredible.
Who knows, some fan in the US may yet have these Pertwee era stories on video tape. I think if all the episodes could blend both methods, giving us the best of both methods, that these episodes would then look identical. Sadly that is not possible at this time. I look forward to seeing their next pass at restoration.