why was the usa the only one to go to the moon?

[JayUtah]

As far as I know, the color emulsion was standard Ektachrome.

Yes, the E-3 process.

I don't remember if we've discussed why it wasn't Kodachrome, which has better dye stability.

More latitude in the darkroom.  The theory was to have professional photo lab people correct the mistakes of amateur astronaut photographers.

Rumor has it that Kodak developed Estar film for spy satellite photography, which makes a lot of sense.

Yes, the Estar base was invented for Project Corona and, at the time of Apollo, was still secret.

[ka9q]

The lenses were replaceable.  On the J-missions they took a 500mm lens for shooting mosaics of distant terrain.

I'm pretty sure those were separate cameras with 500mm lenses permanently attached. They were carried in addition to the usual EDCs with 60mm lenses. They did take some spectacular pictures, such as the west face of Hadley Rille and the flanks of the mountains around the J-sites.

I think there were two likely reasons to make the lenses fixed in the surface cameras: a) removing them on the lunar surface would invite in too much dust, and b) each lens/reseau plate combination was carefully calibrated before flight, and removing a lens would disturb this calibration.

[ka9q]

Yes, third-generation star trackers can go from no-initial-fix to 90% confidence of a 3-arcsecond tolerance in a little under a minute.

I wonder how hard that would be to build from scratch with cheap CCD cameras. I'm thinking of an AMSAT application.

[cjameshuff]

I wonder how hard that would be to build from scratch with cheap CCD cameras. I'm thinking of an AMSAT application.

There's parts available that are basically a camera-on-a-chip, a sensor (often CMOS instead of CCD) and everything needed to read out an image, sometimes even with on-chip resampling and JPEG compression. I've actually been wondering if they have the sensitivity needed for a star tracker...

[frenat]

If I may make my guess, at this point he is trying to get banned.

anybody figure out how to do a lunar rendezvous without an IMU alignment yet?  I'm looking into that.  I know that's a touchy subject.

Only in your mind.  You've been told before why you're wrong.  Why should they tell you again?

[ka9q]

There's parts available that are basically a camera-on-a-chip, a sensor (often CMOS instead of CCD) and everything needed to read out an image

My main concern is the sun. Even though modern cameras aren't damaged by it, it will severely overload the sensor and produce major artifacts like bleeding. If I could knock the sensitivity down enough to minimize these artifacts, I could use the sun's position in the image as attitude data. Alternatively I'd have to build a separate dedicated sun sensor, or simply analyze solar cell currents to determine the sun's direction.

I'd also want the sensor to recover quickly enough to provide usable star field images when the spacecraft is spinning and alternately viewing the sun and dark sky. Of course there would be a limit to the tolerable spin rate as it would limit exposure times and sensitivity would suffer. Maybe I'd need some other kind of attitude sensor for this situation and reserve the star trackers for when the spacecraft is almost stable.

Sunshades would be a good idea to minimize lens flares when the sun is just outside the field of view. They seem standard on commercial star trackers, but bulky.

As for sensitivity, nearly all of the stars in the Apollo catalog were 2nd magnitude or brighter, yet the astronauts still complained that they were often hard to see.

[frenat]

HOW DO YOU FAKE A ROCK?

Dontcha know that NASA can do anything it sets its mind to, except go to the Moon.

So they used the:

The New and Improved MagiTech™ MoonRock Oven®
Will fool every geologist in the world, even those you haven't bribed yet!*

(*Not available in this and the next 3 parallel Universes. Sales Taxes where applicable.)

Come to think of it, how many geologists live in million-dolar mansions and drive Maseratis?

Why so testy?  Sounds like someone who knows they're on thin ice.  I must be striking a nerve.  The truth does not suffer investigation.

So why don't you start investigating.

So far you have only mindlesly regurgitated nonsense fabricated by hoax promoters.
Why are you such a sheeple?

You should be nice to me.  I'm the one trying to get you off the moon.  I'm not regurgitating nonsense.  My nonsense (IMU alignment) is original.  I understand your discomfort with originality.  Sheeple?  Moi?  That's called "projecting."  A great man once said, or maybe it was Pee Wee Herman, "I know you are but what am I?"


Psychological projection or projection bias is a psychological defense mechanism where a person subconsciously denies his or her own attributes, thoughts, and emotions, which are then ascribed to the outside world, usually to other people.

It may be "original" but it is still crap.  You prove with every post that you have no idea what you are talking about.  Rather humorous actually.  You were going for humor, right?

[cjameshuff]

I'd also want the sensor to recover quickly enough to provide usable star field images when the spacecraft is spinning and alternately viewing the sun and dark sky. Of course there would be a limit to the tolerable spin rate as it would limit exposure times and sensitivity would suffer. Maybe I'd need some other kind of attitude sensor for this situation and reserve the star trackers for when the spacecraft is almost stable.

CMOS sensors generally behave better when overloaded...you don't get whole lines obliterated. You might use sun tracking to get control of your rotation, but I think it'd be better to just use a MEMS gyro for a first approximation than to try to find a cheap image sensor that can spot stars while the sun is sweeping through the field of view.

[frenat]

anybody figure out how to do a lunar rendezvous without an IMU alignment yet?  I'm looking into that.  I know that's a touchy subject.

It's not a touchy subject.  Everyone but you knows how to do it, and how it was done.  Don't pretend your ignorance on the subject is anyone's problem but yours.

Did Apollo 11 go to the moon and land while still faking the video?

Prove ANY of the video was faked.  I'll bet you that you can't.

[gillianren]

The vast majority of medium format still cameras used the 61.5mm wide "120", "220" or "620" films

Learn something every day! I handled a lot of medium format film way back in my junior high school photography days, and I'd always just assumed it was the same width as 70mm movie film, just no sprocket holes. I never measured it or did the math.

The only film camera I ever personally owned was a 120.  It came in these little cartridges that you just dropped in place.  I think my dad had owned a camera that used the reel kind, one that he'd bought in Germany when he was there with the Air Force, but my older sister inherited that, and by the time I bought a camera as an adult, it was a digital.

[ka9q]

Cartridges? 120 film came in rolls, little metal or plastic spools maybe 2cm in diameter. You dropped it into the supply slot, cut the tape holding the paper leader in place, and threaded it across the camera into the takeup spool.

Were you maybe thinking of the "Instamatic" format, aka 126? They used molded black plastic cartridges that you just dropped into place. There was also a "baby" Instamatic format, 110.

Those cartridges were a pain to develop. You had to break them open in the dark, usually by smashing them on the corner of the countertop, and fish out the film to put on the developing reel.

[gillianren]

Okay, it was the 110, I think.  I know it was 1-something, but I haven't had the camera in years.  Why would I?  They probably don't make film for it!

[nomuse]

I still miss my little Minolta 201.  Took a lot of pictures on it, got very used to manually dialing in.  And loading the film under the shade of a jacket.

[PetersCreek]

Okay, it was the 110, I think.  I know it was 1-something, but I haven't had the camera in years.  Why would I?  They probably don't make film for it!

It could have been another Instamatic cartridge: 126.  It was much larger than 110, producing images about 26 mm square.  As I recall, the film stock was also 35 mm wide.

ETA:  Ach!  Beaten to it by ka9q.

[gillianren]

No, it was a small cartridge, the smallest available.