Videokarma.org TV - Video - Vintage Television & Radio Forums

Videokarma.org TV - Video - Vintage Television & Radio Forums (http://www.videokarma.org/index.php)
-   Early Color Television (http://www.videokarma.org/forumdisplay.php?f=36)
-   -   Lighting experiment - WWOC on CTC-5 (http://www.videokarma.org/showthread.php?t=274323)

old_tv_nut 09-02-2021 05:58 PM

Lighting experiment - WWOC on CTC-5
 
I spent most of yesterday and the day before trying different ways of lighting my CTC-5 to be able to see the cabinet but not wash out the (dim) picture, to get some shots of "Wonderful World of Color." I ended up using two remote flashes aimed at the ceiling through honeycomb light modifiers to prevent spill light. (It turns out two were necessary to get enough output from this indirect light.) The flowery "TV light" on top of the set added the warm glow on the back wall. Camera was set manually to F/10, two seconds, ISO400. The resulting light on the furniture was still dark and was increased with the Shadows control slider in Lightroom. The room was quite dark, which is hard to tell in the pictures. Texture, Clarity, Sharpness (with masking) and Detail were also increased in Lightroom. There was no need for noise reduction. Some moire' is visible, and appears to be mainly in the greens and yellows.

After all this, I missed the most important shot, the title, so today I took a separate screen shot with the same settings but no flash, and overlayed it on one of yesterday's shots. All the other shots were taken yesterday as described above.

A few more are at https://www.flickr.com/photos/old_tv...57719776551752

https://live.staticflickr.com/65535/...ed750d98_b.jpg

https://live.staticflickr.com/65535/...35d8cf95_b.jpg

Electronic M 09-02-2021 06:13 PM

Looks great.

etype2 09-02-2021 06:40 PM

I love seeing this and you did a great job. Especially like the butterfly and parrot shots. The lit channel indicator displays well.

Nice iconoscope display.

Penthode 09-02-2021 10:15 PM

The lighting is excellent! The key appears to be the rear lighting and diffusion of the front. The shot has a good contrast ratio.

Have you done any absolute measurement of peak white off the CRT before blooming? Would be curious to see if I can borrow a light meter to do some quantitative brightness tests. Certainly it would be interesting to compare 21AXP22 brightnesses.


The 21AXP22A in my CTC5 appears to be tracking well but is noticably dimmer than the 21FP22 in the RCA CTC 11 and even the well used CRT in the Zenith 24NC31Z. I assume this to be normal.

old_tv_nut 09-02-2021 10:49 PM

Quote:

Originally Posted by Penthode (Post 3236211)
The lighting is excellent! The key appears to be the rear lighting and diffusion of the front. The shot has a good contrast ratio.

Have you done any absolute measurement of peak white off the CRT before blooming? Would be curious to see if I can borrow a light meter to do some quantitative brightness tests. Certainly it would be interesting to compare 21AXP22 brightnesses.


The 21AXP22A in my CTC5 appears to be tracking well but is noticably dimmer than the 21FP22 in the RCA CTC 11 and even the well used CRT in the Zenith 24NC31Z. I assume this to be normal.

Is your CTC-5 the Super (cost cut) or DeLuxe chassis? This is a Super, which has pitiful brightness due to low high voltage, and I suspect lower video drive as well. I have been having thoughts of checking the high voltage and retubing the H output / high voltage section, which I haven't done since I got it running. Then it might make some sense to measure brightness. I can tell you that the 21AXP22 was visually dimmer than the 21FBP22 when I swapped it in.

According to a paper by Austen E. Hardy of RCA, the white-light efficiency of CRTs increased as follows:

Tube Type, Lumens per watt:

15GP22 0.6
21AXP22 1.0
21CYP22 1.4
21FBP22 (all sulfide) 2.6
21FBP22A (early vanadate rare-earth red) 2.9

kvflyer 09-03-2021 09:56 AM

Yes, that looks great and I wonder just how many people actually understand the significance of this thread?

OT if I may, I also like your display of the iconoscope and Image Orthicon. I have then as well and want to display them. Thanks!

ceebee23 09-04-2021 04:15 AM

wonderful shots!!! Like others here... I love the Iconoscope and Image Orthicon and Zenith stereo...

These shots remind me just how astounding color tv must have been in 1957! Imagine your grandparents and the whole family sitting down to watch COLOR! what a thrill...


All times are GMT -5. The time now is 02:37 PM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2026, Jelsoft Enterprises Ltd.
©Copyright 2012 VideoKarma.org, All rights reserved.