any tips on Astronomy (star) Photography???

[elfyrulz]

I have a EOS 300D with kit lens and I wanted to ask if the kit lens are good enought to take a picture of stars? (kinda notice that if I set the lens to infinity the stars arent that sharp) also which ISO setting should I used?

[jaypie77]

Good timing! I started doing astrophtograhy last night and I'm spennding the next two nights trying to catch an aurora or other cool stuff (galaxies and nubulae I hope).


Anyway, I was using the 50mm 1.8 last night, ubt I plan on trying the kit lens tonight for a few shots. I think it should be fine as long as you can get it set up with a steady tripod or something like that. I'm going to the store in 2 hours (when work ends) to get a wireless remote (RC-1) and a tripod (which model exactly, I'm not sure).

Anyway, go out this weekend, take lots of shots, experiment a lot, and let's meet up here on Sunday night to trade stories and results and to discuss technique!

Oh yeah - you actually asked a question...

I tried with ISO of 1600 and 800, I had better sharpness with the 800, of course. Still, in theory, you could set the ISO pretty low if you set the aperture and timing correctly.

If you have $80, go out right now and get a 50mm 1.8!

[Canuck]

I recon the 50mm would be good for a wide shot of the nite sky. I have gon the way of the Sigma 120-300mm F2.8EX and got these 2 pics that have been posted so far.
F7.1 and 1/60 sec for the first one and unsure about 2nd one.
http://images.fotopic.net/?id=2161111
http://images.fotopic.net/?id=3188930

I can only recommend whatever you get, please don't go cheap! Stay away from the Sigma 70-300mm F4-5.6DL macro, that lens is crap! I have heard better things about the APO version, but I can't say for sure. I'm thinking the Sigma 50-500mm F4-6.3 EX might be good for this to start. It has the reach for sure and is an EX lens. I on the other hand can slap on a 2x TC and have a 96omm F5.6 lens on my hands. The major down side to my lens is the cost. It was $1900 when I got it in Aug, 2003. I don't know if is has gone down in price since.

[Jon]

A search here will bring up a thread pointing to this Canon tutorial (http://web.canon.jp/Imaging/astro/index-e.html) (among other threads). If you want more than star trails or meteor showers, you need something somewhat bigger. And with astrophotography, unlike with normal photography, it's the absolute diameter of the aperture that's critical, not the relative (f/ stop) value. So a 200 f/4 is faster than a 50 f/ 1.8. This is because we're dealing with point light sources, not planar surfaces. Note: photographing the moon, you're photographing a planar surface; f/ stop rules there.

[jaypie77]

http://www.texbrick.com/photo/notes/astro.html

This guy has various examples with kit lens.

[elfyrulz]

Anyway, go out this weekend, take lots of shots, experiment a lot, and let's meet up here on Sunday night to trade stories and results and to discuss technique!

I wanted to but sadly Stars doesnt show in Northern Atlantic (New Jersey)

[c0ntr0lz]

i'm trying to hook mine up to my dad's HUGE 8 inch telescope and i'm missing one piece to do this with.

[ejhunt]

Found a neat trick to avoid dragging my lazy behind out to get a wire remote...

On the Digitial rebel (probably varies on other bodies), Enable Mirror Lockup
and set to Timer mode. This basically adds a 2 second delay, plenty of time to get your
hand away from the camera (of course the camera is on a tripod).

Obviously can't use bulb feature, though, but will work on exposures up to 30 seconds long.

[kfong]

it's the absolute diameter of the aperture that's critical, not the relative (f/ stop) value. So a 200 f/4 is faster than a 50 f/ 1.8. This is because we're dealing with point light sources, not planar surfaces.

And for a 200 f/4 the (light polluted) sky gets darker while the stars get brighter. The f/4 also has a bigger depth of field for tolerance in focus error.

An important item that haven't been mentioned in the posts are the issues of focusing. The manual focusing rings of EOS AF lenses are just not precise enough for shooting astrophotos. IF you want pin-point star images you'll need to rig up some mechanical gearing system attached to the focus ring to be able to focus precisely.

Ken

[Jim_T]

Focusing on stars can be a problem.. You can AF on the moon if it's in the sky.. Once you have the camera correctly focused, then switch the lens to manual focus..

If there is on moon, on trick is to focus on distant lights (if you have any nearby).. The headlights of a distant car or very distant street lights will usually work in a pinch. Right now in the evening, you can focus on Venus.. It's bright enough for the lens to see..

If you want detail, you can't take very long shots, because the stars move.. They'll start to streak.. How badly they streak depends on whether you're pointing at the north or south sky and the focal length you're using..

I'm currently thinking of getting a sky tracking mount for my tripod.. The mount works like a clock and moves the camera at the speed of the stars.. This allows for long exposures with no streaking..

With a tracking mount, there are lots of interesting things you can shoot with 'regular' lenses.. Below is the Andromeda galaxy taken with a 50mm f/1.8 lens and no tracking mount.... (Its a tight crop.. a bit noisy, slightly out of focus and the streaking is just starting but not bad for a first try )..

[GyRob]

although the stars are moving its the earths rotation thats the headake.
Rob

[kfong]

I'm currently thinking of getting a sky tracking mount for my tripod.. The mount works like a clock and moves the camera at the speed of the stars.. This allows for long exposures with no streaking..


Ah.., now you're opening a new can of worms. A tracking mount will have it's own set of problems : polar alignment, mount flexure, periodic error, microphonics, just to name a few. The rule of thumb is to spend more money on the mount than on the optics.

Ken

[PhotosGuy]

ask if the kit lens are good enought to take a picture of stars? (kinda notice that if I set the lens to infinity the stars arent that sharp)
&
Focusing on stars can be a problem.. You can AF on the moon if it's in the sky.. Once you have the camera correctly focused, then switch the lens to manual focus.. ... and then tape that ring down 'cause vibration might change the focus for you! That ring is the only thing I really hate about that lens. I can work around the other problems.