Hi everyone first of im new so dont shoot me if this has been asked 100's of times before. I have been looking into astrophotograhy and i am hoping i have everything i need.

First of i want to shoot with my DSLR cammera (Nikon D200), i am aware that i will need a t-mount and a t-adapter. what i am wondering is there away to mount my camera to the telescope with a lens on it? As i would like more control over my exposure or is a t-adapter they only way i can set this up.

I'm not sure why you say using the lens gives you more control over exposure. Is there something about the D200 that requires a lens to adjust the exposure time? I wouldn't think so. But I don't use a DSLR so I don't know. I did use a film SLR for years, always without the lens. The lens just gets in the way. Its diaphram only reduces the field of view when you stop it down, it doesn't change the exposure to any extent, at least in my SLR.

I assume you are talking about photographing the moon and planets. To do that you project an image onto the sensor. For low power you just use the telescope's objective to do this. It is called prime focus. For higher powers you project the image through a barlow or eyepiece. I much prefer barlow projection as it seems to have less distortions and a flatter field. By increasing the projection distance you increase the magnification. Same as increasing the distance of a projector from the screen increases the image size. Stacking barlows is allowed. You'll likely find the sweet spot is about f/30 for maximum resolution on planets or the moon. Though this depends on your pixel size. Larger pixels will need a higher f ratio.

For best results a web cam usually is preferred to a DSLR. Their advantage is they can take a thousand images in a minute or two. Software finds the best of the best and stacks them for further processing. You can't begin to do this manually with a DSLR so you have to hope you get lucky and trip off a shot when seeing is good.

Covington has two books you should read. The first covers the basics of astrophotography the second is specific to the DSLR
http://books.google.com/books?id=ZT0...with-thumbnail
http://www.covingtoninnovations.com/dslr/

I'm not up on books for web cam planetary photography. Here's a website that covers it fairly well.
http://www.astro.shoregalaxy.com/webcam_astro.htm

You'll note in the astrophoto forum most planetary imagers use web cams not DSLRs because of their ability to get the most out of limited seeing opportunities. Though their chip size is smaller making mosaics often necessary for the moon, but not planets.

Rick

Afocal imaging is imaging with the camera lens on through the eyepiece. It is for planetary and lunar, but not so great for deep sky. Here is an adapter to do afocal imaging.
http://www.telescope.com/control/pro...oduct_id=05228

Afocal imaging has more flexibility, but prime focus is better for stability.

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hi first of thanks for the messages i think ill give one of the books a shot.

I have been trying out the astronomy over the last few nights however im having real problems the minute i attach the t-mount. once i attach the t-mount i can no longer focus on anything in the night sky i've spent a whole night just trying. if i remove the t-mount i can see what is up there perfectly. anyone have any advice as to where im going wrong?

as for the a-focal system from what i have seen im not sure that would be stable enough to hold my camera i would be looking at using a prime lens it would just mean that i could do further focusing on the camera as well as having more control over my exposure(im a photographer first so i want to control my apeture. idealy i am just now trying my hand at planets and the moon but if i have luck with that may move for deep space stuff though i would buy a camera for that