I'm thinking of taking a shot of the Andromeda Galaxy with my 600mm at f/4 with 3200 speed film pushed one stop for 20 seconds. Can this be done undriven with this setup or should I resort to a clock drive? Will it expose the film in 20 seconds? Do I have enough magnification for this object? Thanks, SR

-- Steve Rasmussen (srasmuss@flash.net), June 24, 1999

Answers

Welcome back Marcelo. Thanks for the suggestion. I will try to piggyback on a large scope and use slow film and long exposure. BTW, Andromeda is the most distant object seen by the naked eye. Also, after some research, I found that its angular size is 6 times that of the full moon. Visually through a telescope, it looks much smaller. SR

-- Steve Rasmussen (srasmuss@flash.net), July 07, 1999.

Marcelo: Yes, Andromeda is huge and is six moon diameters in angular size. It is much larger than our galaxy. My 600mm should be OK for that except I should probably drive it for best results. SR

-- Steve Rasmussen (srasmuss@flash.net), July 12, 1999.

Hi Steve,

I doubt you will have enough magnification for the Andromeda Galaxy. In my observational astronomy class, we used a Meade telescope which magnified the equivalent to around 1000mm (in 35mm photography) and even then we could barely see the galaxy. I think your best bet for that kind of astrophotography is to use a telescope and a sky tracker; there are many sites on the web about this, specifically with photographers who use the P67. With the tracker you can also use lower speed film, but you will probably need to expose for a few hours.

Regards, Marcelo

-- Marcelo P. Lima (MPL4@cornell.edu), July 05, 1999.

Hi Steve,

Hmm...that's intriguing. So maybe I'm confusing Andromeda with some other object. But if it's angular size is 6x that of the full moon, shouldn't it cover six times more room on the sky than the full moon? So the problem with it is that it's much fainter than the moon. This is where using a telescope proves better; the main purpose of telescopes is to be light buckets, or photon-collecting lenses, if you will. Because of their larger diameter, telescopes can "see" fainter objects than camera lenses. But I'm still curious about Andromeda's size...

regards, Marcelo

-- Marcelo P. Lima (MPL4@cornell.edu), July 12, 1999.