Astrophotography help

Hello! So i have been doing much research about astrophotography for a very long time now, now I have took the time to drive 150 miles out of Los Angeles into the middle of the desert. It is pitch black out here and the sky is SO beautiful. I did a test run today and i didn't get anything I was expecting, quite disappointing. But I guess my more skilled friends just make is look easy. I have a Canon 60D and the lenses I have with me are Tokina 11-16 2.8, 24mm 2.8, 18-135mm 3.5, and a 50mm 1.8. I'm getting the best results with the 11-16. Now if i'm wrong help me out but it seems like I'm doing everything right. there is NO light population. I'm using bulb mode and using a Canon wireless remote and a tripod. Long exposures and high ISO(640-1600). I took all the UV filters off my lenes. I keep changing the aperture ISO and exposure time to see what is best, but nothings really i get really dark images with no stars or I get ones too bright. Can any of you please help me?

This is the best picture I have yet to get, very little editing.

http://s233.photobucke​t.com …¤t=IMG_96​1bvjv6.png

There is an astronomy / astrophotography section on here, you will probably get more answers if you re-post in there.

There is an astro section to look at for more info.

The general idea/problem with most astro shots (unless you're shooting bright nearby planets, or wanting star trails) is that the rotation of the earth causes the stars to move. You need to let a lot of light in (= long exposures), and so you get blur/trails of the stars. The way to overcome this is with a tracking mount of some kind as normally used for telescopes - things get complicated/expensive quickly.

You can get away with some fairly basic tracking set ups with wide lenses. Look at "barn door mounts" for example.

11-16 @ 11mm on a tripod. f2.8, ISO800, 20s exposure. Manual focus using liveview and a bright star. Point the camera towards the Milky Way (and if you can't see it with the naked eye you'll probably not get the results you want), shoot, chimp raise or lower ISO as needed.

You can make a reasonable estimate of your exposure before blurring using this little formula...

Exposure (seconds) = 36* PixelPitch (microns) / FocalLength (mm)

Using the 60D, I get that an 11mm lens will allow about 14 seconds of exposure. You may find that your lens is out-resolved by the sensor and you can go to 30 seconds, but you can be sure that you can use at least 14 seconds.

You can also record multiple images, align them and stack them together. I use MSB-AstroArt for this but you can do it with a number of packages, some of which are free. If you add four images together, you improve the signal to noise ratio by about 1 stop. A two stops improvement requires 16 images and three stops requires 64 images... Each of which has to be accurately aligned.

It's a good idea to record the camera's noise by shooting several images with the lens cap on and stacking these too. This is far better than Canon's implementation of dark frame subtraction because it just leaves you with random noise from the image rather than random noise from the image plus random noise from the dark frame.

Dark frames are somewhat temperature sensitive so you may want to record the temperature and collect a set of noise frames to suit a range of temperatures. You can then re-use the sets.

Finally - a shameless plug. There's a 2700-member group on Yahoo that specialises in astrophotography using Canon DSLR's. If you're interested, here's a link. Full disclosure - I'm one of the moderators. If you do apply, please spend a minute to explain your interest... "Hi" or "I'm interested" is too much like a spam-bot.

Really good tutorials at http://www.astro.shore​galaxy.com/dslr_astro.​htm.

Thank you for the tips, I'm new to the site so i don't know where to post certain things it took me 30 minutes to find out how to post a thread. Hopefully I can get better shots tonight!

noisejammer wrote in post #14655779
You can make a reasonable estimate of your exposure before blurring using this little formula...

Exposure (seconds) = 36* PixelPitch (microns) / FocalLength (mm)

Using the 60D, I get that an 11mm lens will allow about 14 seconds of exposure. You may find that your lens is out-resolved by the sensor and you can go to 30 seconds, but you can be sure that you can use at least 14 seconds.

You can also record multiple images, align them and stack them together. I use MSB-AstroArt for this but you can do it with a number of packages, some of which are free. If you add four images together, you improve the signal to noise ratio by about 1 stop. A two stops improvement requires 16 images and three stops requires 64 images... Each of which has to be accurately aligned.

It's a good idea to record the camera's noise by shooting several images with the lens cap on and stacking these too. This is far better than Canon's implementation of dark frame subtraction because it just leaves you with random noise from the image rather than random noise from the image plus random noise from the dark frame.

Dark frames are somewhat temperature sensitive so you may want to record the temperature and collect a set of noise frames to suit a range of temperatures. You can then re-use the sets.

Finally - a shameless plug. There's a 2700-member group on Yahoo that specialises in astrophotography using Canon DSLR's. If you're interested, here's a link. Full disclosure - I'm one of the moderators. If you do apply, please spend a minute to explain your interest... "Hi" or "I'm interested" is too much like a spam-bot.

Thank you. I'm not even getting star trails I can't even get them without the picture looking blown out. I'm really disappointed in myself for these images and it was quite embarrassing even posting a picture i took. I'll keep testing out exposure and ISO, and i'll see what I can get tonight. And i'm new to the site, I don't know really how to work it yet. How can I post my question in a "astronomy / astrophotography section" Thank You

You don't say which settings you were using... The Tokina 11-16 is a great star lens because it's pretty fast for a wide angle..

Here's a shot taken in my front yard with the Tokina and my 7D.. It shows the northern lights low on the horizon behind my pine tree windbreak. There is a touch of sodium vapor street lamp light pollution from a nearby small town 10 miles to the north of me. It adds a slight amber cast to the sky. The shot is shrunk to fit the posting rules, but no changes were made to the levels, contrast, color, sharpness etc.

Focal length 11mm
Aperture f/2.8
ISO 1600
Exposure time 20 seconds
.

Jim_T wrote in post #14657445
You don't say which settings you were using... The Tokina 11-16 is a great star lens because it's pretty fast for a wide angle..

Here's a shot taken in my front yard with the Tokina and my 7D.. It shows the northern lights low on the horizon behind my pine tree windbreak. There is a touch of sodium vapor street lamp light pollution from a nearby small town 10 miles to the north of me. It adds a slight amber cast to the sky. The shot is shrunk to fit the posting rules, but no changes were made to the levels, contrast, color, sharpness etc.

Focal length 11mm
Aperture f/2.8
ISO 1600
Exposure time 20 seconds
.

Wow thats fantastic! I've used many different settings to try to get photos. I have tried at aperture 2.8 and ISO of 1600 but if I have the shutter open for more than 15 seconds I get bright blue / blown out photos. I don't think its the lens because the lens is about 1 week old and i just got my 60D sensor cleaned from Canon. Hope I get better shots tonight. Thank you i'll try it out again

DBAKED wrote in post #14656929
Thank you. I'm not even getting star trails I can't even get them without the picture looking blown out. I'm really disappointed in myself for these images and it was quite embarrassing even posting a picture i took. I'll keep testing out exposure and ISO, and i'll see what I can get tonight. And i'm new to the site, I don't know really how to work it yet. How can I post my question in a "astronomy / astrophotography section" Thank You

Don't be embarrassed about posting bad results, it's part of learning!

You say blown out, is it light pollution? Is the sky not very clear? It's a reason why you should post the results, so people can help ID the problem.

Astro-photography has a steep learning curve. Lots of good advice already posted above. Your first shot isn't bad at all. Shoot multiple RAW images and convert to TIFFs, and then stack them. I use the free program RegiStax. Join Astronomy Forum... lots of good reading and people willing to help a newbie. And, most of all, have fun.

phreeky wrote in post #14658113
Don't be embarrassed about posting bad results, it's part of learning!

You say blown out, is it light pollution? Is the sky not very clear? It's a reason why you should post the results, so people can help ID the problem.

The sky is so clear! I see more stars than what show up. I'm about 120 miles form LA and 30 miles from palm springs literally in the middle of nowhere, I wish i can blame me photos on light population but no. If i get better results i'll post them!

ScubaDude wrote in post #14658755
Astro-photography has a steep learning curve. Lots of good advice already posted above. Your first shot isn't bad at all. Shoot multiple RAW images and convert to TIFFs, and then stack them. I use the free program RegiStax. Join Astronomy Forum... lots of good reading and people willing to help a newbie. And, most of all, have fun.

I tried downloading the RegiStax but i think its only for PCs . I normally don't ever edit my photos in photoshop but guess its about time I read those manuals. I've stacked photos before but never noticed a change in the photo outcome. and i shoot in RAW! Thanks

Yes, it looks like RegiStax is PC only (or Linux/Wine). Another GREAT resource is Jerry Lodriguss' e-books... well worth the money. His "Beginner's Guide" is mostly stuff you can learn for free on the internet, but "Photoshop for Astrophotographers" is, in my opinion, a must-have e-book.