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ImageMaker
04-30-2006, 01:00 PM
Another Polaroid from the AutoPin 210 on WPPD. Last frame in this pack, which has been in the camera for a couple months; don't know if that's a light leak on the right, drying out of the gel from being open too long, or some other fog source -- ISO 3000 is awfully easy to fog...

Type 667, f/320, auto exposure appr. 3/4 second (hand held). Attached files http://f295.f295.org/uploads/10_7182.jpg (http://f295.f295.org/uploads/10_7182.jpg)

earlj
04-30-2006, 04:32 PM
That's a nice one, Donald. I am still amazed that you managed to make an auto exposure pinhole camera that works.

dannykalkhoven
05-04-2006, 02:16 AM
Imagemaker,

What? Automatic exposure? Amazing!

Sometimes a "last one in the pack" makes everything worthwhile, see my "backlight bench" thread!
But the again, that pack did not stay in my camera for such a long time, less then one hour ;-)

Danny

Andrew
05-04-2006, 05:13 AM
no caterpillar ? maybe the fog was the little fella making his exit...

ImageMaker
05-04-2006, 03:28 PM
I didn't "make" autoexposure, I just converted the Polaroid system to work with a pinhole as long as I load only Type 667 film. Polaroid did the hard work; in the case of the 210, around 1963...

Steve Smith
05-09-2006, 09:10 AM
I have a query about your Autopin 210. Am I right in assuming that you use ISO300 film but leave the camera set for IS0100 (or is it ISO80?) and the 5 stops difference is then compensated for by the fact that the pin hole is a lot smaller than the aperture it thinks it's got?

I have done a conversion to a similar Polaroid pack film camera, I think it was a 360. It's somewhere in here: http://www.f295.org/DIYforum/cgi-bin/forum/Blah.pl?b-equip/m-1146826169/

Steve Smith

Steve Smith
05-09-2006, 09:11 AM
Sorry, that should have said ISO3000 film not ISO300!!

Steve.

ImageMaker
05-09-2006, 12:45 PM
Steve, the camera's film selector is locked at 3000. In order to compensate the exposure for the pinhole, I placed a small aperture, and, after testing, a piece of neutral density over the light sensor, by way of convincing the camera's 2-transistor "brain" there's a lot less light than there actually is. I very seriously doubt this would work with slower films (even ISO 400) because there'd be so little range of light in which exposures could run below the camera's automatic exposure limit of something like 10 seconds. With the ISO 3000, even behind a pinhole at about f/330, I get full-sun exposures as short as about 1/4 second, and it can be fairly dim and still stay well under 10 seconds.

The original aperture for ISO 80 film is f/8 or so; five stops smaller would still only be f/45, or about the normal aperture for the ISO 3000 film (there's actually a little less difference, IIRC from f/8.8 to f/42; originally there was a grid that slid over the sensor on the slow-film setting to make up for that variation).

buggy
05-24-2006, 02:30 PM
Nice one.