AS16-116 stain

[trebor]

Hey people,
On the images in the Apollo 16 film roll 116 they all have a brown stain which is the same in each image on the roll.
Does anyone know what it is and where it came from?

[Data Cable]

My first guess would be some foreign material (glue on the beginning of the roll?) that was trapped between the film and reseau plate when the film cartridge was installed, which then got smeared as the film advanced.

Edit: The same stains are visible on roll 114, starting with frame 18444. From ALSJ:

Readers should note that the smudges visible on frames 18444 to 18470 at the end of the magazine are most likely on the original film. The scans linked below were made by NASA Johnson from the original film in about 2005-6. Identical smudges appear on scans made from prints and negatives which derive from duplicate negatives made long ago from the original film, probably not long after the film arrived in Houston from the Moon. Because the original film is the only common ancestor, the smudges are necessarily on the orginal film. The fact that the film was in the LM cabin between the time 18443 and 18444 were taken may be significant.

Note that frames 18442-3 are both completely sunstruck (as is 18444, slightly), which suggests the magazine was removed. Apparently this is when the contamination occurred.

[trebor]

Sept 27, 2009 14:09:35 GMT -4 Data Cable said:

Edit: The same stains are visible on roll 114, starting with frame 18444.
Note that frames 18442-3 are both completely sunstruck (as is 18444, slightly), which suggests the magazine was removed. Apparently this is when the contamination occurred.

That is interesting.
I see that the film roll 115 does not have the stains. So the chronology goes from 114 to 116?
It would be good to know why the camera was opened in the LM at that point.

Edit:
Thanks for the help Mr Cable,
It was very handy

[Data Cable]

Sept 27, 2009 15:20:44 GMT -4 trebor said:

I see that the film roll 115 does not have the stains. So the chronology goes from 114 to 116?

115 was loaded in Charlie Duke's camera. 114 and 116 were in John Young's, which apparently contained the contaminated reseau plate. And, going by the brief summary here, I don't think the magazine numbers are necessarily chronological. e.g. 105 and 106 were used on EVA-3, 107 and 108 on EVA-2 and 109 on EVA-1. It's a bit of a scavenger hunt through ALSJ to track down when the magazines were swapped out.

Thanks for the help Mr Cable,
It was very handy

Not a prob.