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  #211  
Old 05-18-2018, 11:11 PM
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Does this smear (left set) show up when the color is all the way off? Hard for me to tell from the photo if its in the luminance, but I'm guessing it is.

If I had to guess without further investigation, I'd suspect the IF alignment around the video carrier. A non-symmectrical Nyquist slope can do this kind of thing. To do some diagnostics, turn the chroma all the way down. If it's still there, see what happens when you change the fine tuning. If it gets wider and narrower as you turn the fine tuning left and right, it may be alignment.

The pic on the right set seems to have a bit of a ghost to the right of objects, which could be a bit of delay line ringing.

Again, these are only guesses without exploring further.
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  #212  
Old 05-18-2018, 11:16 PM
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If you watch the video, the shadows only appear occasionally. This scene is the worst.
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  #213  
Old 05-18-2018, 11:29 PM
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Quote:
Originally Posted by old_tv_nut View Post
Does this smear (left set) show up when the color is all the way off? Hard for me to tell from the photo if its in the luminance, but I'm guessing it is.


If I had to guess without further investigation, I'd suspect the IF alignment around the video carrier. A non-symmectrical Nyquist slope can do this kind of thing. To do some diagnostics, turn the chroma all the way down. If it's still there, see what happens when you change the fine tuning. If it gets wider and narrower as you turn the fine tuning left and right, it may be alignment.


The pic on the right set seems to have a bit of a ghost to the right of objects, which could be a bit of delay line ringing.

Again, these are only guesses without exploring further.
Don’t know, will check.

We had a textbook alignment curve after completing alignment.

We have put on about 125 hours on the set since restoration one year ago. Stuff drifts, etc.
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Last edited by etype2; 05-18-2018 at 11:32 PM.
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  #214  
Old 05-18-2018, 11:39 PM
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I will do some testing on Saturday. Preparing for an all nighter with the live Royal Wedding.
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  #215  
Old 05-18-2018, 11:40 PM
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Well, I've caused enough trouble for today - going to get ready for bed.
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  #216  
Old 05-19-2018, 12:54 PM
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I think that if the image were any smaller, one would be unable to see just how well the image on the set has been restored.

I never would have believed there could be an image this good from a 15G.
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  #217  
Old 05-19-2018, 02:44 PM
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Quote:
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I think that if the image were any smaller, one would be unable to see just how well the image on the set has been restored.

I never would have believed there could be an image this good from a 15G.
You mean 21AXP22.

The 21CT55 (CTC-2B/CTC-3[they gave the convergence board it's own CTC#]) uses a 21AXP22.
The RCA CT-100 (CTC-2 plain) uses a 15GP22.

I should know; I've (somehow) got an example both models, the chassis are side by side on my bench.
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  #218  
Old 05-20-2018, 01:50 PM
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Quote:
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I think that if the image were any smaller, one would be unable to see just how well the image on the set has been restored.

I never would have believed there could be an image this good from a 15G.
There is a link too see the images in full resolution in the post.

https://visions4netjournal.com/2018/...-carousel-5083
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  #219  
Old 05-20-2018, 02:11 PM
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I’ve posted shots of “Kiss Me Kate”, “Ferris Bueller’s Day off”, “Gone With The Wind”, “The Red Shoes”, “The Wizard Of Oz” and “Gentlemen Prefer Blondes” and videos from the 21CT55 at this link.

https://visions4netjournal.com/2018/03/07/movie/

Here is Ferris and girlfriend in 1500X1000. The above link has them in 6000X4000.



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Last edited by etype2; 05-20-2018 at 02:25 PM.
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  #220  
Old 05-20-2018, 02:42 PM
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You can see what Wayne is talking about with DC restoration. In the first photo, the letterbox band at the top is black, but at the bottom it is blue. In the second photo, her hair is normal but too blue at the bottom of the screen.

I hadn’t noticed this until Wayne brought it up. The first thing will be some testing and a tube exchange.
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  #221  
Old 05-20-2018, 04:11 PM
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On the other hand, I would expect to see a blue push at the bottom of this shot of Jane Russell’s dress. The problem if it exists, is hard to see from movie to movie and scene to scene.

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  #222  
Old 05-20-2018, 04:37 PM
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Quote:
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On the other hand, I would expect to see a blue push at the bottom of this shot of Jane Russell’s dress. The problem if it exists, is hard to see from movie to movie and scene to scene.
The letterbox emphasizes the problem in Ferris...The thing about DC restoration issues is their effect is dependent on video content and strong contrast transitions...Even the lousiest monochrome TV set without any DC restoration will look normal if the video content does not force the problem to be apparent...Conversely relatively decent sets if given just the right program material to illustrate the imperfections in their DC restoration can look really bad...This is why test patterns exist, to push a set to its limits and show it's deficiencies.

What you need to see the problem is a letterboxed program or something with similar characteristics.
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  #223  
Old 05-20-2018, 05:38 PM
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Agree.
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  #224  
Old 05-20-2018, 06:15 PM
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Whoa! Look at Tournament of Roses Parade #2, at 01:26 and following, and 01:58 and following. In these scenes, much of the background is neutral pavement. In the 21CT55 there is a 60 Hz blue hum bar moving slowly upward. The CTC-5 also has a hum bar, but it's weaker and different.

Some portion of these effects could be caused by a beat between the TV video and your camera sensor, but I don't see how your camera could cause two different effects on the two sets like that. It seems like there's some hum in the color circuits or the blue matrix/amplifier, which sometimes makes the bottom bluer and sometimes not. The DC restorer *might* be able to take out hum, but then again maybe not, if the time constants are long.

Besides checking DC restorer operation, maybe you should be looking for the hum.
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  #225  
Old 05-20-2018, 06:19 PM
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By the way, I thought I caught a brief glimpse on one of the videos (sorry, I can't find it again) of the CTC-5 hue pulling momentarily in the top third of the picture. I have this problem with my CTC-5 occasionally when there is a strongly colored area at the left of the picture, and the horizontal hold is slightly off, causing the burst gate to let in some picture chroma. I haven't bothered to put a scope on it to see if the burst gate pulse is too wide or something.
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