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[RobbW]

Just for a point of reference, when it comes to astrophotography, what could you expect to image just using a camera not attached to a scope? Say I have my DSLR, a 300mm zoom lens, and a steady tripod, what could I take pics of? I assume my 300mm lens will give me more reach than my 10x50 binos, but nowhere near as much as my 5" scope. So if I can at least see an object in my binos, I should be able to get a better look at it with my 300mm lens, right? Or am I not thinking properly? Of course, since I would be using my camera on a non-tracking tripod, I would have to take shorter exposures.

[Chicago Astronomer - Astro Joe]

Robb,

The 300mm zoom lens screams out for longer exposures and other than the Moon, (being so bright), and without tracking...would be a lot of trails and smears.

You may be able to just start to catch some things solid with a very high ISO, 1600 0r 3200, but the grain might not make it a good pic.

I say that the direct viewing of objects with the 300mm lens would be too dim. Such high powered lenses on cameras are quite slow - ( maybe f-5.6 or so), limiting the light coming into the camera and your eye. I got good results with my old 35mm film camera with a 80-200mm zoom of the Moon, but without tracking, I was pushing the limit - even with fast film. And I was never able to capture anything else worthwhile.

You could attach the camera piggyback and have the scope track while imaging...but I don't know if the motors will carry the extra weight - but worth a try. Many have got great images of naked eye nebula and the Milky Way spanning overhead like this. I haven't tried it yet, as my camera only has a max exposure of 15 seconds, but there is a hack to extend the time and other features on the Canon Powershot S3.

So, the limited light that the camera 300mm lens is able to gather might disappoint.

[RobbW]

Thanks for the info, Joe. Yeah, I hadn't thought about the slowness of the lens. Tracking's going to be an issue,too, since I don't have a working mount that tracks.

[RobbW]

Well, I tried my hand at non-tracking astro pix of the Andromeda Galaxy the other night using my DSLR with 300mm zoom @ 3200 ISO. I took about 100 exposures at 5 seconds each, as 5 seconds was about the limit to prevent any star trails at all. I ran the images through Deep Sky Stacker and came up with....... crap! The final stacked image was basically all black with only a couple pinpoints of stars. No image of the galaxy at all, even though I was able to see the faint bulge in all the original photos. So, that was pretty much a waste of time and energy.

However, now that I have my new, trusty, actually-working, tracking motor mount (thanks to Galileo Telescopes), I'm thinking of trying my hand at some guided astro pix. My only problem now is that I have no way of attaching my DSLR to my tracking scope. Also, I have no way of knowing if the motor mount will even be able to handle the extra weight of the camera.

Is anyone aware of any simple MacGyver-style methods for piggy-backing a camera onto a scope? I don't have any fancy-schmancy piggy-back mount that costs $100, nor do I want to spend that much. I'd like to be able to jimmy-rig something as quickly as I can and possibly try using it tonight. Anyone have any ideas? Or am I S.O.L. until I can purchase a proper camera mount?

[Paulie pchris00]

Jul 13, 2010 14:56:31 GMT -6 RobbW said:

Well, I tried my hand at non-tracking astro pix of the Andromeda Galaxy the other night using my DSLR with 300mm zoom @ 3200 ISO. I took about 100 exposures at 5 seconds each, as 5 seconds was about the limit to prevent any star trails at all. I ran the images through Deep Sky Stacker and came up with....... crap! The final stacked image was basically all black with only a couple pinpoints of stars. No image of the galaxy at all, even though I was able to see the faint bulge in all the original photos. So, that was pretty much a waste of time and energy.

Consider it a lesson learned, instead of a waste of time and energy. You may have saved somebody who reads this the trouble you went through.

That does suck, though...

[Chicago Astronomer - Astro Joe]

Robb,

Not wasted effort.

Thomas Edison went through thousands of elements in search of a material to use in the incandescent bulb. When asked why didn't he give up, as apparently each one was a failure and so much time involved.

"No", he said.

Each one was a victory in getting closer to what eventually worked.

But, now you know too, what does not work...and won't do it exactly the same way again.

It can only get better.

[mojocvh]

Guys newbie Mo here.

I don't want to upset the applecart or anything OK.

BUT I found the twain site to have not only excellent images but with some VERY interesting composition and it has certainly given me some "ideas" about combining pure earth based astro photography (which some might say has been almost done to death perhaps)with images that "break the mold" and certainly will grab the public's imagination.

Just my 5c worth!

Awerabest,

Mo.

www.twanight.org/newTWAN/index.asp