[X] My Assistant

[DDAVIS]

I have a page on Apollo which is updated annually. Do others feel more optimistic than i do on the prospects for return? I for one won't believe we will leave LEO until the hardware to do it is actually being built.

http://www.donaldedavis.com/PARTS/Apollo30.html

[dvandorn]

The problem with the Apollo 14 camera was in its electronics, although it was using a different vidicon coating than had been used on the three earlier color cameras developed for Apollo.

The first color camera was put together just barely in time to fly on Apollo 10. That same camera was re-flown on Apollo 11, although a back-up camera had been built by the time 11 flew. The first camera was used inside the CM only on 10 and 11.

After Apollo 11, the in-cabin camera used on 10 and 11 was re-packaged and mounted on the LM descent stage for Apollo 12. It was the camera that was burned out by being pointed into the sun. Apollo 12's CM camera was the back-up developed for Apollo 11.

The camera on the Apollo 13 LM was identical to the cameras previously flown in terms of vidicon coating and electronics, but it was never used. (Careful use of a lens cap was to protect it from direct sun-imaging burnouts.) The camera on the Apollo 14 LM was of the same design, but had a new and different type of vidicon coating that made it less susceptible to damage from direct sunlight (although they still used a lens cap).

The real problem with the Apollo 14 camera was a bad component in the peak light control circuit. Instead of making the video signal balance to the peak lighting elements in the scene, it exaggerated peak lighting elements. The quality of the images from that camera when it was opened up all the way (biggest aperature), at the beginning of EVA-1 when it was looking into the shadow of the LM at the foot of the ladder, was actually quite good -- except that the sunlit surface beyond bloomed up and made the descending astronauts look like they had little tiny stick legs. But when Shepard came close to the camera as he took off the MESA blankets, the detail on his visor assembly and RCU was quite good.

Image quality was poor but acceptable when the camera was looking cross-sun. But when they set it up looking down-sun (during the ALSEP deployment from the SEQ bay and, later, during the setup of the ALSEP), the crew and their equipment were nothing more than big white blobs. It's a shame, since this was the only time the deployment of the ALSEP from the SEQ bay was televised or filmed, and the images are of extremely poor quality.

The glitch in the peak lighting circuit resolved itself somewhat by the beginning of the second EVA, and the images during EVA 2 were better. But since a vast majority of EVA 2 was spent with the camera pointed at the wrong segment of Cone Ridge to see any of the traverse, it really made no difference to the overall poor taste the Apollo 14 camera left in the public mouth.

I sort of wish they had gone to Plan B, which had been part of the planning on both Apollos 13 and 14. On both of those missions, the LM actually carried a back-up TV camera, a black-and-white camera identical to the unit used on the surface during Apollo 11. It was strapped to the side of the LM and covered with a thermal blanket. If the color camera was burned out on one of these missions, the crew was supposed to replace it with the B&W camera. I sometimes think the B&W camera would have given better pictures during EVA-1 than the color camera did.

On the J missions, of course, they used a much better color surface camera, capable of generating 525-line (NTSC-compatible) output. It still used the sequential field color wheel system, but it had a much sturdier vidicon coating (those cameras got pointed directly into the sun several times and never suffered a problem). Those cameras provided near-studio-quality video from the Moon during those missions -- a vast improvement over anything we saw during the first three landings.

-the other Doug