Need some advice on setting up my DSLR to Telescope

[InnesUK]

Hi folks,

this is my first post on here. My friend has been in to astronomy for ages and has a (starter) reflector telescope called a TASCO MODEL 45-076280. I'm into photography so thought we'd try and combine our skills and start trying to take images of the moon and planets. Well thats the plan anyway.

From reading some threads on here I believe I need a T mount to attach to my Olympus E550 (Four Thirds) via the cameras Bayonet mounting. Something like this?

http://www.firstligh...rs/t-rings.html

I then screw the T-Mount onto the Focus part of the telescope? I measured the diameter of the Focus tube and its 1.5 Inches.

The T-Mount above doesnt mention diamters but Im sure I saw in other threads that the standard size is 2 Inches? if so is the diameter of this telescope smaller be cause its just a starter telescope and a little inferior?

The telescope also has an erecting eyepiece 1.5x and a Barlow Lens 2x. These have threads for the eye piece but the T-Ring doesnt go on here does it? Diameter for thread looks to be 1 1/4 Inch in Diameter.

I just need some pointers and that I'm going to buy the right adapter for my needs. if anyone else has this setup (or similar) then that would be great to see what your experience of astrophotography has been like.

Thanks everyone,

Innes

Eye Piece thread

[Stargazer33]

Hi Innes,

You can also get a 1.25" nosepiece that the T mount screws into. This effectively turns your camera into an eyepiece. You then just slot this into the focus tube of your scope as you would an eyepiece.

Similar to this: http://www.firstlightoptics.com/adaptors/flo-125-inch-t-mount-camera-adapter.html

HTH

[MattGoo]

You could also experiment with widefield imaging, put your smallest (<50mm) and fastest (<F3 ish) lens on your camera, mount it on a tripod, point it at the sky, focus, do 10-20 second exposures with a remote shutter release and see what comes out!

[ronin]

The telescope also has an erecting eyepiece 1.5x and a Barlow Lens 2x. These have threads for the eye piece but the T-Ring doesnt go on here does it? Diameter for thread looks to be 1 1/4 Inch in Diameter.

I presume these are seperate items and are not built in as part of the focuser. I do not think they are on the 76/700, mainly concerned that it might be a bird-jones design and there is a barlow in the focuser.

Assuming not then you may have difficulty getting the camera in close enough to achive a focused image on the camera sensor, if so you may need to put the barlow in as this often causes the image to move out and so get an image on the sensor. No guarantee however and the image is biger so dimmer.

Does the 1.25" section of the focuser come out ?

I am thinking that it will not as the focuser will be fairly basic but on some the focuser is 2" with a 1.25" insert for eyepieces.

Start out wih the moon. It is big and bright, at f/10 1/250 sec iso 200, or even less should give something, reduce the iso if too bright, as this reduces the noise. Start expecting the image to be fairly small, they always are. Good aspect is you simply delete what you don't like. The moon is a nice narrowish cresent at present.

Previously mentioned but take a tripod, camera and widish lens and wander up towards Yelverton. Set tripod and camera up and aim at the milky way, set exposure for 20 sec and then 30 sec, not sure of an iso but try 400 and 800 and see what comes out. One combination should be good. After 30 seconds I would expect trailing to start to show up.

For any of this I hope you have a cable release, pressing the button with a finger results in too much shake.

Could use the timer option if no cable.

All this will have to be done with camera in manual mode.

[malc-c]

Innes, I think you are going to struggle fitting a dslr to a Tasco scope. These are designed to take 0.96" eyepieces rather than the now standard 1.25" and 2" formats. You'll also find that the thread on the end of the draw tube is not the correct pitch for a T-Adapter.

For Luna and planetary imaging you would be better off getting a 0.96" to 1.25" adapter ( http://www.telescopehouse.com/acatalog/Adapter--AD-2-fits-.965in-foc.-07501.html ) and use a webcam with a 1.25" fitment

[mitchelln]

I tried this a couple of years ago. You may encounter a problem with the 0.96" to 1.25" adapter. It adds length to the optical path and you then may not have enough travel on the focuser to get the image in focus on the camera.