New Book on Apollo TV Technology

[MeteorWayne]

I've become aware of new book describing the TV systems used for the Apollo broadcasts in transit and on the lunar surface. There was quite a bit of advancement over the relatively short period from slow scan B&W to much more resolution and higher scan rate color video.

First Camera:
The RCA Block I TV Camera was used sucessfully on the first manned flight of Apollo 7, and was also the camera which brought the world its first live look back on itself during the flight of Apollo 8...
Camera Specifications:

•RCA Vidicon tube
•Lines per video frame: 320
•Frame rate: 10 frames per second
•Black and white

Last Missions:
The RCA Ground Controlled Television Assembly (GCTA) was used on the last three missions of Apollo 15, 16 and 17. It was mainly mounted on the Lunar Rover and remotely controlled via commands sent from Houston. Thus people were able to watch the lunar launch of the LM at the end of the lunar EVAs.
Camera Specifications:
•Frame rate: 60 frame/s BW / 20 frame/s color (color filters alternated between each field)
•Color: Field-sequential color system
•Spectral response: 350–700 nm
•Sensor: Silicon Intensifier Target (SIT) Tube
•Optics: 6x zoom, f/2.2 to f/22
•Automatic light control (ALC): average or peak scene luminance

Personally, as a child of the Mercury through Apollo missions, and a 35 year technician/engineer on television broadcast and test and measuremant products, it sounds really interesting to me. :ugeek: :ugeek:

Once I get a chance to read it, I'll report more.


http://www.livetvfromthemoon.com/About_the_Book.html

Wayne

 

[Woggles]

Hi MW Thanks! I would be interested in hearing the updates. I just may buy it too!

 

[adrenalynn]

That definitely sounds like something I should read.

I've been long-stunned by the amazing quality of the lunar mission videos compared to commercial broadcast television of the day. The video masters hold-up well today, even when upscaled to ATSC/HD. That sixty field with broad spectral response explains much of why it holds up so well, I think.

It's also amazing how far we've come. My friends and I are sending up 1080p/60/12 for a 4.6oz weight budget and a couple hundred dollars to near-space in April. Imagine how far we've come just in your career, MW!

 

[Dstevenb]

Hi everyone. I'm the author of said book. If any of you have any questions pertaining to Apollo era TV I'd be happy to answer them for you.
I'm always happy to talk with fellow space enthusiasts.

regards
Dwight

 

[adrenalynn]

Hi Dwight,

Firstly - thanks for offering your expertise, and welcome to SDC!

Disclosure: I've ordered your book, but haven't read it yet (expect to receive it Monday).

The Westinghouse Lunar Surface Camera captured my interest. 1280 line (@ 0.65fps)

Throughout your descriptions, you use Frames per Second rather than Fields per Second. Were all the cameras progressive scanning?

What was the scoop on the 1280 lines? Were they doing multiple scan/multiple field and combining it into a frame? In Cam? That just seems light years ahead for their time! What were they going to project it with back on the ground?

Thanks for any insight! Greatly appreciated!

 

[MeteorWayne]

I'm still trying to find some wiggle room in my budget

The cat needs another oil change, and i'm falling further in debt every day

 

[Dstevenb]

Hi adrenalynn,

IIRC the WEC slow scan camera was 10 fps progressive. I need to check that as I dont have my notes with me. The later color field sequential cameras were all 60 fields per second. The color converter used a delay trick to compensate for problems in mismatched fields when matrixing the color signal.

I was discussing the high-res mode with the honeysuckle creek engineers earlier this year and none of them could recall any particular documentation for the equipment which would have been necessary to replay the image. I only have maybe two or three memos/reports regarding the setting. All I can really say is that it definitely was a feature of the camera. Unfortunately Stan Lebar passed away before we could ask him more about it.

regards
Dwight

 

[jimglenn]

I was only a teenager, but clearly remember one mission where the astro aimed the camera at the sun,

said "there is the sun" and it bloomed out and destroyed the tube. I knew this was bad because was

working with some Ampex 1" reel to reel school recorders, in a class they said not to aim the camera

at bright lights. That incident may be mentioned HERE:

http://www.hq.nasa.gov/alsj/ApolloTV-Acrobat5.pdf

Yeah, see page 28.

 

[Dstevenb]

Hi jimglenn,

yeah Al Bean mistakenly pointed the camera at the sun while moving it from the MESA to its final resting place (similar to A11). The internal electronics mistook the burnt out section of the image tube as being a bright object and stopped the signal down to being virtually black. There was no easy over-ride function and so the TV camera was essentially rendered useless. Had the AGC been bypassed, the camera was still operational and would have supplied some useful images, albeit with 1/4 of the screen burnt out.

The modifications made to subsequent cameras after that mishap allowed them to be pointed at the sun and on later J-missions you can see this modification working as the cameras pan past the sun.

 

[3488]

It was unfortunate as the Apollo astronauts were all trained to never, ever point that camera at the sun directly. It clearly shows how much difficult the real EVAs on the Moon really were as compared to their training.

Surely that camera could have been powered down & 'rebooted' restoring the factory defaults????? As said, even a quarter frame burnt out, the ramaining 75% would have been very useful.

Andrew Brown.

 

[Dstevenb]

Hi Andrew,

unfortunately the powering down of the Apollo 12 TV camera wouldn't have changed anything. What needed to be done was cut a wire controlling the Automatic Gain Control, and that wire was not accesible without opening the camera housing. Later cameras were modified with a bypass switch.

Stan Lebar did say one thing about the mishap though - and that was it finally hammered home to NASA how crucial TV was on the missions. Every mission since Apollo 12 has always had redundancy plans to ensure TV is never an afterthought occurance.

regards
Dwight

 

[adrenalynn]

And now we (my little team and I) have 960 line / 60 progressive frame wide dynamic range cameras that will fit on a quarter with a wide field lens, store 12hrs of recording in that size, and draw just 85uA... What hath Bell Labs wrought?

 

[andrew_t1000]

I'll have to get a copy of that book!

Just recently a box of video tape (reel to reel) and cine film, not sure which format, I'd guess 16mm, was found in the basement of the Perth Uni, it was discovered to be the "missing" footage from the Apollo 11 landing.
Somehow the video and film got from Parkes radio observatory to the basement of Perth Uni.

 

[Dstevenb]

Hi Andrew,

I certainly would be very happy if you did grab a copy of "Live TV From the Moon"!

Regarding the Perth Uni story: the tapes were unfortunately _not_ the missing material sought after by the search team. There are only the experimental 2" tapes still not accounted for which may show up one day. In the 6 years of looking for the telemetry material, only a simulation recording for Apollo 9 was uncovered. The restoration team has located the best possible _scan converted_ material and has had the Lowry Digital team clean up the footage. Compared to the kinescopes (film recodings of the video signal) the restored stuff looks fantastic!! Once the Parkes antenna kicks in, you can see a good deal of clarity which comes close to how the telemetry raw signal might look.

The bonus DVD included in "Live TV From the Moon" includes the press conference from July 16, 2009 in which NASA presented the news of the tape search and presented snippets of the restored video.

regards
Dwight

 

[adrenalynn]

You're definitely on my reading list, Dwight!

I'm still slogging through the last half of Fundamentals of Astrodynamics (Bate, Mueller, White) - it's a sleeper for sure.

Wishing your publisher was more ebook friendly. Be nice to kindle it on the go!

 

[Dstevenb]

Hi adrenalynn,

You never know what the future holds for Apogeebooks and kindle! If they move to digital, I'll definitely put my hand up to try it out. However until that time, you'll have to make do with the old fashioned version (at least you can get autographs in it!!).

Speaking of which, when you decide to buy you can either get through usual means, or if you would prefer a signed copy, I have a few still at home. PM me here - though be warned I am in Germany, so postage to the US aint cheap!

Ideally I'd like to have the book be successful enough to convince the publisher that the follow-up dealing with Skylab, ASTP and the Shuttle TV systems should get published as well. The story behind TV on those projects is as interesting as the one which got TV to go to the moon.

 

[jimglenn]

Thanks for the data. I had thought the sun burned the phosphors in the tube. They did a great job back then

considering the level of technology that was available.