Night Sky Star Shots

<p>Hello Guys,<br>

I am using F3 and would like to try to achieve a night sky star shot. What film should I use, what aperture and shutter setup is most ideal? How do you meter the light to get proper setting?<br>

All I know is I'll need a sturdy tripod, telephoto lens is ideal. I should prob use cable shutter with mirror lock up to avoid minor shake. <br>

Although I am shooting film, digital knowledge are welcome too.</p>

<p><img src="http://www.utahskies.org/image_library/deepsky/messier/m045/M45_2_Sky_6x4_150dpi_edlunt.jpg" alt="" width="900" height="606" /></p>

<p>William, Is this image yours? Is this an example of what you are already doing? There are some good articles in the learning section here.</p>

<p>http://www.photo.net/learn/nature/sunmoon</p>

<p>and this one is very detailed: http://www.photo.net/learn/astro/intro</p>

<p>I'll watch this post with interest, as I'd very much like to have a go with my DSLR.<br>

I have a good motor driven telescope, and with it a CCD 'astro imager' but I've never managed to get decent results with the imager, so would love to try with my camera.<br>

Forgive me if you know the basics, but<br>

- One of the problems is going to be that to get the right exposure means long exposure times, and that means without some form of drive, the stars will appear as elongated ovals rather than points. That can add to the 'artistic' effect but is a nuisance if you want a true representation of the constellations etc.<br>

- Next problem will be that with long exposure, you're going have to be certain there's not the faintest amount of stray light about - with my DSLR that maybe means using all the noise reduction techniques available.<br>

-my limited experiments so far have suggested the longer exposure the better, subject to the above - I'm not sure any meter is going to cope with it, just go 'B' and maybe try 1 minute, 2, 3, etc...</p>

<p>No Michael, it is not my image. It is just an example what I would like to achieve.<br>

If I were at cloudless outdoor, sky always seems to be the same color most of time. Deep blue/black with bright stars.<br>

Don't know how exactly to meter in such extreme situation. Since the sky color will be constant, I thought there should have a good math formula to take such shots.<br>

I thought digital group will be interested too since it might be slight easier than expose on film. Fundamental shouldn't differ too much.</p>

<p><strong>ISO: </strong>100? 400? 800? Both film and digital will suffer the same noise issue.<strong><br /></strong><br>

<strong>Aperture:</strong> Should Aperture be wide or small? and why?<br>

<strong>Shutter Speed:</strong> I know it should be long shutter but how long? 3min+?<br>

ISO X Aperture X Shutter<br>

If I know the method to meter and nail one of the variant down, pretty much the other two can be adjusted accordingly.</p>

<p>That image was shot, I suspect, with what you need. An excellent telescope on an equatorial mount.</p>

<p>The larger physical opening you allow to gather light at night, the more photons reach the film/sensor. The higher ISO, the more light again. </p>

<p>Unless you have an equatorial drive and a good telescope and a "clean sky sweeper" to clear all moisture, dust and light pollution away where you shoot, you will never get results like the one you showed taken from 14,000 feet high in the Andes through a 5m telescope that cost a few hundred million dollars to build and the same to maintain.</p>

<p>Try star trails instead; the earth turns once by 360 degrees in every 24 hours, so by 15 degrees in every hour, etc.<br>

So open up your lens, point at the clearest part of the sky, expose for 2 or 4 or 8 or 15 minutes on a tripod and look at the trails in your pics to decide what gives. It helps if you can identify true north (= Polaris) in the sky. Just play and see!</p>

<p>Astro-photography is a great hobby Michael which can take you from the simple to the complex.</p>

<p>The image you posted is M-45, or "The Pleides" star cluster. The image is easily duplicated with a (guided) motor drive, a 400mm lens @ f/4 and about a 8-10 min exposure.</p>

<p>This forum is far too limited to give you precise step by step instructions as astro-photography bears little resemblance to terrestrial photography.</p>

 

<blockquote>

<p>I have a good motor driven telescope, and with it a CCD 'astro imager' </p>

 

</blockquote>

<p>As a side note to this poster; a CCD imager is only one element required to attain great results. Standing alone it is almost useless w/o some rather sophisticated stacking software, dark frame calibrations and semi precision guiding.</p>

<p>Back in th day, precision guiding was paramount; today not so much as multiple images of shorter exposures are now stacked after CCD capture.</p>

<p>1) Start small. Get a good equitorial mount with motor drive, and a periodic correction controller.<br>

2) Learn to polar align with precision. These instructions are everywhere if you google them.<br>

3) Piggyback the camera and fire away.</p>

<p>Its a good way to start..anymore will bury you in too much complexity too soon.</p>

<p>The image above might be a little extreme, but how about something more like this?<br>

<img src="http://markunrau.com/wp-content/uploads/2010/08/night_sky9030_thumb.jpg" alt="" width="630" height="420" /></p>

<p>William,<br>

Not sure why the above posters are making this so complicated. This is actually simple to do and with better results when shooting film.<br>

Here's how I would capture the shot you've posted above. Place the F3 on a tripod with Ball head. Use a cable release. I'd suggest slide/transparency film (iso 100 or 200) as during processing no auto corrections will be made. I'd use a fast Nikon Manual Focus lens from 24mm to 50mm. I prefer the MF ais lenses because they have a hard stop at infinity so you know you're obtaining excellent focus. Set the aperture at a stop or two down from maximum aperture meaning if you're using a 50mm lens with a maximum aperture of f/1.4 I'd be shooting at f/2 or f/2.8. Depth of field will not be a problem - you're focused at infinity and should you choose to place something in the foreground (such as the trees in the photo above) they are far enough from you to be in sharp focus at infinity. You're going to be making quite a number of exposures at different exposures. I believe the F3 has a 'B' mode. Use it and start shooting away! Exposures of anywhere from 20 seconds to several hours. The longer the exposure the more the stars will "trail". You could also try "painting" the trees in the foreground with a flashlight for a few seconds. Experiment. Fresh batteries, a good flashlight, plenty of film (I'd suggest Fuji Provia 100), proper clothing and a location that's very dark without auto traffic. The attached shot shows what happens when you think you have a dark sky however with a long exposure I'm getting the glow of Las Vegas in the distance. Enjoy yourself and try a number of different shutter settings. <br>

Dave</p><div></div>

<p>Neglected to mention aircraft - avoid an area under commercial air routes, they'll add light as travel across your image.<br>

Regards,<br>

Dave</p>

<p>Thanks Dave. I'll give a shot this weekend at camp site :D</p>