You don't need a telescope

victorelessar wrote in post #13861164
guys what is the cheapest atrotrack (im not sure if atrotrack is a brand or the actual object. but i meant the tool rly)?
i say that because here in brazil i cant find anywhere that sells it. and to import would be very expensive for me, so im afraid id have to lose a bit on quality in order to have one.
i see here some equatorial mounts. perhaps it would be cheaper to buy one of those and later try to find the motor for it?

You can get a lightweight EQ mount with tracking motors for a reasonable price. Probably less expensive than the Astrotrack..

Another option for simple DSLR astrophotography is to build a Barn Door Tracker (Scotch Mount)..
here's an example >> http://www.jlc.net …TM/Barndoor/bar​ndoor.html
And another with the plans. http://www.philharring​ton.net/scotch.htm

tkerr wrote in post #13858838
That depends on what you are after. If you want a real wide field of view to cover more area of the sky then the 8-16mm would be a good choice. But then at those focal lengths, especially the shorter, you will start running into the problems that have been discussed above such as field distortions, coma and vignetting.

However, the wider you go the more tolerant it is to the movement of the stars across the sky. IOW you will be able to get a longer exposure which will collect more details in the night sky.
Typically a good starting figure for shutter speed before trailing will be noticeable is to divide 500 by the lens focal length. Or if you're using a Full Frame Camera try 600 by the focal length. It's not perfect but it will get you close.
For Example with the 8-16mm Sigma @ 8mm on a camera with an APS-C crop sensor you can go as long as 62 seconds
With the other lens at 17mm you can only go as long as about 30 seconds.

Thanks for the info! No mention of f/stop should i be shooting in build more and manuallu timing these exposure times or just shoot in ****ter priority (for the exposures of 30 seconds or less) and I'm guessing focus should be manual at infinite?

Thanks for helping a noob get his feet wet!

tkerr wrote in post #13862003
You can get a lightweight EQ mount with tracking motors for a reasonable price. Probably less expensive than the Astrotrack..

Another option for simple DSLR astrophotography is to build a Barn Door Tracker (Scotch Mount)..
here's an example >> http://www.jlc.net …TM/Barndoor/bar​ndoor.html
And another with the plans. http://www.philharring​ton.net/scotch.htm

thanks! it seems that building one is the best option for now. ill see what i can do

S.n.a.f.u. wrote in post #13862107
Thanks for the info! No mention of f/stop should i be shooting in build more and manuallu timing these exposure times or just shoot in ****ter priority (for the exposures of 30 seconds or less) and I'm guessing focus should be manual at infinite?

Thanks for helping a noob get his feet wet!

With either of those lenses I recommend going back a page or two here and read what has been posted about stopping down from wide open.. Only one or two stops from wide open should be enough... Otherwise you want to allow as much light in as possible. Additionally, Start with ISO 1600, if that's too much or too noisy then try ISO 800.

As for timing the shutter speed you can set it to the closest speed or use the Bulb setting and a remoter shutter switch or Intervalometer..
Focusing might be a little tricky and is often the most difficult issue for people to accomplish. You want to focus at infinity, but lenses with auto-focus go beyond that, so you don't want to just turn it all the way. Additionally, if you're lens uses a slide zoom you want to make sure it is locked in position so it won't slip while the camera is angled high toward the sky taking the exposure.

The idea is to capture as much light in the amount of time before you start seeing significant star trailing. Unless of course the idea is to create a star trail image, then it won't matter.
https://photography-on-the.net …/showthread.php​?t=1131579

Here's my go at the Orion Nebula with 7D and 100-400L at 400mm, on a homemade tacking mount. I get quite bad light pollution here and am still trying to find the best way of processing it out, so I apologise for the slightly weird sky.

PHOTOBUCKET EMBEDDING IS DISABLED BY THIS MEMBER. Photobucket sends ads instead of embedding photos from their free galleries. Click the link (if available) below to see the image in a gallery page. http://i72.photobucket​.com …kle/Canon/small​1098-1.jpg

Todd Lambert wrote in post #13309954
No, I'm from TX. Drove 12 hours on Fri to get there and shoot all Sat night and then 12 hours back on Sun.
Ouch!

Yes, the 16-35 is one of my favorite lenses - especially for night stuff. I've thought about the 14L, but I just don't think it could replace the 16-35, as it's still only 2.8 and of course not a zoom. Most of the time, I am now using a 24L just because it goes to ƒ1.4 which is awesome for night stuff. Couple the 24L with a 5D2 and there really isn't a better setup for night shots.

Todd/anyone, quick question. I'm using a T2i with a 16-35 L lens. I can't seem to ever get my night shots in focus. Looking on the screen after the shot everything looks great. Then I get it home and on the monitor and see it's all out of focus. Help? I've tried zooming in after taking a shot but it's alot of hit and miss, mostly miss.

Beardy wrote in post #13875309
Todd/anyone, quick question. I'm using a T2i with a 16-35 L lens. I can't seem to ever get my night shots in focus. Looking on the screen after the shot everything looks great. Then I get it home and on the monitor and see it's all out of focus. Help? I've tried zooming in after taking a shot but it's alot of hit and miss, mostly miss.

With zooms, it's important to find the point on your lens that it's actually at true infinity. This point can vary a bit and even lining things up on the lens, doesn't work all the time. I would recommend using LiveView during the day, focus on something manually, until you get infinity.

Then, memorize that spot on your distance scale on the lens. Once you memorize that spot, it's really simple to get correct focus even in pitch black conditions (of course you'll need a lighter, or flashlight in order to set the right spot on the lens).

That's what I do and it works really well.

Todd Lambert wrote in post #13875534
With zooms, it's important to find the point on your lens that it's actually at true infinity. This point can vary a bit and even lining things up on the lens, doesn't work all the time. I would recommend using LiveView during the day, focus on something manually, until you get infinity.

Then, memorize that spot on your distance scale on the lens. Once you memorize that spot, it's really simple to get correct focus even in pitch black conditions (of course you'll need a lighter, or flashlight in order to set the right spot on the lens).

That's what I do and it works really well.

Use a red light filters on your flashlights so your eyes dont dillate losing your night vision

That's a good tip, Tony!

60D, Sigma 120-300 2.8 OS + Sigma and Canon 2x TCs stacked.

IMAGE LINK: http://www.flickr.com …/29108710@N04/6​809858171/

Terrific Moon shot!

Beardy wrote in post #13875309
Todd/anyone, quick question. I'm using a T2i with a 16-35 L lens. I can't seem to ever get my night shots in focus. Looking on the screen after the shot everything looks great. Then I get it home and on the monitor and see it's all out of focus. Help? I've tried zooming in after taking a shot but it's alot of hit and miss, mostly miss.

A trick I use, if available, focus on distant lights, street lights porch lights, doesn't matter as long as they are far enough away they require you to focus at Infinity.
Other than that and what has already been recommended, the only thing I can add is to use a laptop computer with your EOS Utility if you can. That way you can take test shots and get a better look at them to see if they are in focus or need adjustment. Or use Live View via the EOS Utility on the laptop and you will be able to see a bigger picture that will help you get better focus.

When using live view to focus on stars, Increase the ISO as High as you can, and then increase the Live View magnification so that you can see the stars good enough to achieve focus.

Todd Lambert wrote in post #13875534
With zooms, it's important to find the point on your lens that it's actually at true infinity. This point can vary a bit and even lining things up on the lens, doesn't work all the time.

It's not just zoom lenses, but pretty much any lens with Auto-focus..
For smoother operation as well as to reduce vibration or wear and tear from a sudden stop, Lenses with high speed auto-focus go beyond infinity and then back.

However, sharp focus isn't only a function of the lens, but of the camera body as well.
Getting a physical feel for / familiarity with how your lenses and camera body function together will help considerably.

Beardy,
Trying to convince the camera to work perfectly under dark skies with nearly no available light is next to impossible. This is why we must rely on or skill and familiarity with our own equipment when we are in the dark. It's going to take a little time and practice. Even then you won't get it every time. Just keep at it and don't give up.

gabebalazs wrote in post #13875616
60D, Sigma 120-300 2.8 OS + Sigma and Canon 2x TCs stacked.

on Flickr

Wow, that is a Great Lunar image.

I wonder, Without bringing out too much noise, I bet you could processes that image using Lab Color and it will reveal more colors actually captured by the camera. E.g. Blues and Magenta's as well as greens and yellows that reveal the differences in the metallic (iron and titanium) content of the various surface features.
You've already revealed some of it.

Madweasel wrote in post #13873489
Here's my go at the Orion Nebula with 7D and 100-400L at 400mm, on a homemade tacking mount. I get quite bad light pollution here and am still trying to find the best way of processing it out, so I apologise for the slightly weird sky.

this is very cool. my friend is bringing me a sigma 70-300mm, with the crop effect, i might have 480mm, i hope i can get such good result