Exposure settings for astrophotography on film?

<p>I'm going to be camping on a very remote beach this weekend with little to no light pollution so I want to take advantage and take some astrophotography shots. I'll be shooting with a Leica M3 w/ Summicron 50mm f/2 and a Yashica Mat-124 with 80mm f/3.5 lens. <br /><br />Using ISO 400 film, shooting both cameras wide open (f/2 and f/3.5), what kinds of shutter speeds should I be using to get a decent exposure? <br>

<br />Would I be in the 1-5 minutes territory or should I be more in the neighbourhood of 1-5 hours? I really have no idea since I've never done long exposures on film before, but as long as a I have a general idea of what kind of shutter speed I need, I can take several different exposures. <br /><br />Preferably I would like to have exposures under an hour (under 30 minutes would be ideal), since I do not want to have to stay up all night watching my tripod. What kind of settings would yield useable results with shutter speeds under an hour? <br /><br />I would like to get shots of both still stars as well as star trails, so if someone could let me know generally what kind of exposure settings I could use for those respectively, that would be awesome. </p>

<p>This is a great Web site that should answer all your questions:</p>

<p>http://www.astropix.com/HTML/I_ASTROP/toc_ap.html</p>

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<p>As for "still" photos, you'll be best off with a motorized equatorial mount. Otherwise you'll get trails. The longer the exposure, the more stars you will gather on you film. Bright stars will look larger than dimmer stars. Good deep space photos take quite a while.</p>

<p>Star trails - start at f4 for an hour. Then experiment.</p>

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<p>Star trails - start at f4 for an hour. Then experiment.</p>

 

 

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<p><a name="pagebottom"></a><br />Is this for 400 speed film? Also if I wanted to cut that exposure time in half, would it be logical to shoot at f/2 instead? </p>

<p>For still shots I usually go for 30 sec. or less, but not wide open - usually closed down by a stop. You want to be able to reduce the effect of motion blur due to the earth's rotation - may need some post processing, but I've always been happy with my results.. Star trails - whatever floats your boat...longer is better. Just try to center on the locus of rotation (not sure where you are shooting from in the world, it will vary by location).</p>

<p>The website that David listed is excellent. I don't have much to add--just two examples. <br>

If you want to shoot pictures of constellations, it is best to limit exposures to 30 seconds. The background exposure for this shot (a composite of 4 shots) was a 30 second exposure at f/3.5 with 800 speed film.<br>

<img src="https://photos.smugmug.com/photos/i-k4fD8mp/2/M/i-k4fD8mp-M.jpg" alt="" /><br>

If you are shooting toward the poles, you can get by with a longer exposure. In this 2 minute exposure you can see the beginnings of star trails for the stars that are farther from Polaris. The stars closer to Polaris are close to points. Polaris would be just above the center of the top edge of the image.<br>

<img src="https://photos.smugmug.com/photos/i-hN3zGDL/2/M/i-hN3zGDL-M.jpg" alt="" /></p>

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<p>Is this for 400 speed film? Also if I wanted to cut that exposure time in half, would it be logical to shoot at f/2 instead?</p>

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In the case of star trails, you can't cut the exposure and open up the aperture for the same result. The result will be brighter, and shorter, trails. </p>