SLR Astrophotography

[adree]

Im curious on how SLR cameras can be attached to telescopes and how they are taken. Are the adaptors available in the market for SLR cameras a one size fits all kind? nikon/canon/etc ?
When attaching the SLR camera to the telescope, are any camera lenses used? or is the camera body just attached to the scope?

Can anyone explain how it works?

[weixing]

Hi,
You need to get a T-Ring Adapter for your SLR camera. The T-Ring adapter will replace your lens. I think different brand use different T-Ring, since most of their lens mount are different. Depend on your telescope, you may need a 1.25" to T-Ring adapter to connect your Telescope eyepiece holder to theSLR camera.

Hope the information is useful.

[Sam Lee]

There are a few ways which you can attach a camera to the telescope, each for different purpose.

A-Focal - Its like holding the camera with the lenses right in front of the telescope's eyepiece and taking a shot.

Prime focus - This is what weixing mention :-) , placing the camera without any lenses right into the telescope eyepiece holder. Usually this is meant for deep skies photography (example: Shooting the Orion Nebula).

Eyepiece projection - For this case, this is also counted as A-focal, but without the camera lens. A T-ring adaptor is use instead. A eyepiece projection tube is used to connect a eyepiece and the camera together so that there are no external lighting to affect the shot being taken. Then the whole tube is inserted to the back of the telescope. Usually used for Lunar or Solar Photography.

[kayheem]

Im curious on how SLR cameras can be attached to telescopes and how they are taken. Are the adaptors available in the market for SLR cameras a one size fits all kind? nikon/canon/etc ?
When attaching the SLR camera to the telescope, are any camera lenses used? or is the camera body just attached to the scope?

Can anyone explain how it works?

I have started a short article on this in response to your questions. I have not finished it, but I think it will answer some of your questions. Once I have finished, perhaps someone can make it sticky on the Singastro website.

I have currently posted it in the 'Files' section of the singastro-yahoogroups.

Can the admin make a files section on this singastro website?

Kay Heem

[nF]

kayheem, why not you cut and paste your article on the astrophotography forum, then I make it as sticky so it will be more visible for us?

[Airconvent]

kayheem, why not you cut and paste your article on the astrophotography forum, then I make it as sticky so it will be more visible for us?

perhaps it would be neater to create a "resource" link instead as the number of stickies increase. Otherwise we will end up seeing onlly stickies on the first page! Alternatively, create a new locked forum and shift all these gems there, so that people can access it...

rich

[ChaosKnight]

Im curious on how SLR cameras can be attached to telescopes and how they are taken. Are the adaptors available in the market for SLR cameras a one size fits all kind? nikon/canon/etc ?
When attaching the SLR camera to the telescope, are any camera lenses used? or is the camera body just attached to the scope?

Can anyone explain how it works?

Firstly you need a T-ring, which is a metal ring with an internal screw thread and some sort of external thread. The external one attaches to your camera body the way you attach a lens. T-rings are specific to the camera types (Canon Eos for Canon Eos, Nikon for Nikon etc).

Next you need an adaptor to attach the T-ring to your telescope. There are adaptors which can screw onto the internal screw thread of the T-ring at one end and a 1.25" barrel at the other. After you attach the T-adaptor to the T-ring, you can mount your camera like a regular 1.25" eyepiece.
This gives you prime focus photography. You can imagine your telescope acting as the lens for your camera now. Check your telescope. You may already have an external screw thread on your focuser ready for a T-ring, so you wouldn't need this T-adaptor. Magnification as seen from the canera is about the focal length of your OTA divided by 50 (Suppose your OTA FL is 1000mm, magnification is 1000/50 = 20).

Then there are adaptors which screw onto the T-ring and ends in a 1.25"barrel, but these are slightly bigger tubes that can hold an eyepiece inside them. Using these adaptors give eyepiece projection photography. The magnification is more than the magnification given by the eyepiece. (Suppose your OTA FL is 1000mm. A 20mm eyepiece in the adaptor gives 1000/20 = 50X magnification. The view from the camera is more than 50X). This is because the distance from the plane of the lens of the eyepiece to the plane of the film plays a part in the magnification process.

Are you looking for adaptors for photography? My advice: get the 2nd type. By popping in an eyepiece, you can do high-powered eyepiece-projection photography. Without the eyepiece, it's just prime focus photography. Saves you the money for a regular T-adaptor. But you got to make sure your OTA wouldn't be off-balanced by the addition of all your stuff, or look for a new way to balance your OTA.

And one more thing. It's a good idea to invest in a remote. Avoids direct handling of the shutter and reduces vibration.

[addy]

thanks for sharing the info.. nice article indeed.. next question :-)... are the T-rings and eye-piece projection tubes available locally..

cheers
Addy

[weixing]

Hi,
I think Astro Scientific Centre have T-Rings for quite a number of camera brand or you can find it from some camera shop in Peninsula Plaza. As for eyepiece projection tubes, I think you can get it from Astro Scientific Centre, StarMatrix or McGill.

Have a nice day...

[ChaosKnight]

thanks for sharing the info.. nice article indeed.. next question :-)... are the T-rings and eye-piece projection tubes available locally..

cheers
Addy

Yeah they are. Got mine from Astro Scientific. Also, be sure to find out from the vendor all the necessary equippment for mounting your camera.