Having Trouble Succeeding with Astrophotography

[GreggS]

Hi there-

I shoot with a Canon 550D/T2i and I've taken a few stabs at astrophotography. Namely, I'm trying to get some semblance of those clear Milky Way shots you see, with clear banding visible. If anyone has any experience with astrophotography that may be able to point me in the right direction, I'd love some advice. Here are the settings I typically use when trying:

-50mm f/1.8 or Tamron 10-24mm lens
-sturdy tripod
-manual mode: 'bulb'; f/22 or f/29; ISO 100-800 (I experiment within that range); 25-30 second exposures (using a remote timer); manual focus on infinity (when applicable)

If it matters, I'm shooting in Southwest Florida.

Thanks.

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[Aloicious]

how dark is the area you're shooting at? fort myers is pretty light polluted IIRC, try driving out of town a ways, and find a nice darker area (higher elevations help too)

the small aperture is the main problem. f22-f29 are WAY too stopped down. you're blocking practically all the light out.

out of those 2 lenses, I'd use the 50mm because it's quite a bit faster, the wide angle of the tamron is nice, but its a slow lens. I'd be using the 50mm at f1.8 or close to it. you want all the light you can get.

however if you're using the 50mm, you'll probably have to make a series of images and stitch them together like a panoramic because 50mm isn't wide enough to see everything you're looking for. you also won't be able to shoot 25-30s at 50mm without getting star trails. try something more like 10-15s....800ISO is good.

here is a milky way image I made with my D90 + 50mm 1.8 last year. this is a series of 'panels' stitched together, and each 'panel' has several images stacked together to get the most clean light in it....if that makes sense. you can see where a few were stitched together, and the small portion in the upper right corner that I missed.



also shoot in RAW if you're not already. post processing will be the key to bringing out the details...

[Aloicious]

also, here's one from that same night, this is one single image after post processing, you can see how the light from the milkyway is still fairly dim here, this is what stacking multiple images helps with, to help increase the light beyond what you're able to take with 1 shot...(this shot was actually an accidental shutter trip, I didn't mean to get the telephone poles in there, but I liked it when I downloaded the images so I did some processing on it)



that cluster of stars you can see in this image, is the same cluster in the bottom middle of the image in the post above

these aren't world class images or anything, but hopefully it helps you get going in the right direction

EDIT - these were also taken in a dark sky area out in the desert, so if where you're shooting at is more light polluted, it will be harder to capture

[GreggS]

also, here's one from that same night, this is one single image after post processing, you can see how the light from the milkyway is still fairly dim here, this is what stacking multiple images helps with, to help increase the light beyond what you're able to take with 1 shot...(this shot was actually an accidental shutter trip, I didn't mean to get the telephone poles in there, but I liked it when I downloaded the images so I did some processing on it)



that cluster of stars you can see in this image, is the same cluster in the bottom middle of the image in the post above

these aren't world class images or anything, but hopefully it helps you get going in the right direction

EDIT - these were also taken in a dark sky area out in the desert, so if where you're shooting at is more light polluted, it will be harder to capture

Thanks for the great examples and advice. Follow up question--Is there any specific direction I should be shooting to get the Milky Way (i.e. North? South? etc.)

[Aloicious]

if you're in a sufficiently dark area, you should be able to see the active portion of the milkyway with your unaided eye....south south east around 11-12PM would be the best, but remember that it kindof depends on what time of the night you're shooting, since the earth is moving, the position of everything will change a little depending on the time you're looking at it, here is a place with free star charts to help you find stuff, they even list what stuff needs a telescope or not, on their chart the blue area is the general milky way...

Skymaps.com - Publication Quality Sky Maps & Star Charts
also forgot to mention, that if the moon is out, the light from the moon will make it alot harder to capture the milky way, its best to wait for a new moon (which is happening this tuesday) when the moon won't be out at all.

[Garbz]

Wait what? F/22 or F/29? Just a few tips for photography in general:

- When you stop down smaller than f/11 diffraction stars causing sharpness issues on cameras with sensors as small as yours.
- If you can spare an aperture stop to increase the light getting to your sensor and still have acceptable depth of field, then open the aperture rather than increasing the ISO. In the case of shooting space you should be shooting wide open before you even consider increasing the ISO beyond 100.
- If you can't get the required brightness when shooting stars and you don't want to end up with streaks (since the earth rotates) take a series of shorter exposures and stack them together with a program like Deep Sky Stacker. This will track the stars and rotate the pictures accordingly. Then in photoshop you can blend the completed sky shot with a still shot of the ground.