Mounting SLR onto Scope.

[Bloosman]

Hi,

I've had a look on the forum, but can't find an answer to my query, which maybe speaks more about my searching capabilities than anything else...!

However...

I have been happily mounting my Canon DSLR onto my 8" dobsonian via a T-Mount fitted directly onto the 2" focusing tube.

This is fine if I want images of the "whole" moon...

What should I do if I want closer focusing to the target...???

Is it possible to mount the SLR onto an eyepiece for instance, or is there another method that I am missing...???

Dougie.

[Cornelius Varley]

You could use eyepiece projection (eyepiece connected to camera body using a suitable adaptor  http://www.opticalvision.co.uk/astronomical_accessories-camera_adaptors_and_imaging_products/camera_adaptors.html ) . Baader eyepieces  can be connected using a t-ring and adaptor http://www.firstlightoptics.com/baader-planetarium.html. Or use a barlow lens to increase the focal length of the telescope. By using an extension tube between the barlow and camera you can increase the effective magnification of the barlow lens. 

[PeterCPC]

You can do something called eyepiece projection where you fit an extension tube in the focuser with an EP in it and the DSLR fits on the other end. You could also have a Barlow lens between the focuser and the camera.

The problem though might be getting focus with a Newtonian as they don't have much inner travel. Someone with this type of set up will come along I hope to answer your query more fully.

I had a 250 Dob and I had a problem getting focus with my DSLR.

Peter

[Leveye]

With a Newt or Dob style scope you may have to move the primary mirror up a bit to reach prime focus. I removed my focuser and held my rig up to the hole during a full moon and made measurements where i reached focus within the travel of my focuser while moving the primary into the right spot,marking it and then remounting it in that position. You can always put it back to just view if you wish.

[frugal]

It took me ages to get my head around the idea that the focal length was fixed and if you wanted a longer focal length then you really needed a different telescope. If you look at it from a photography perspective then each scope is just a fixed focal length lens. The trick seems to be find outwhatkindof thingyou want to image, and then buy a scope to match.

[RichM63]

This might sound barkingly daft, but, I'm guessing that what you want to see is more detail of a crater rather than the whole Moon.

Have you tried shooting in RAW and then zooming in and cropping to your chosen area. I'm very much still playing with techniques and a DSLR, but am finding that the limitations are more mine rather than the kit.

Adding a Barlow is probably not going to work with focusing, although an extension just might as there is no lens element. There is an expensive optical converter that people use but the name escapes me.

[Bloosman]

Thanks for the replies guys....

What I was looking for was the ability to get a closer image of the moon rather than the entire lunar object, hence my query re attaching to an eyepiece...

What you say about the focal length of my scope being fixed is quite correct, and as a photographer I can't understand why I didn't realise that...doh....!!!

I'll look into the option of eyepiece projection, which I think is maybe what I'm needing...:-)

[Aeseir]

Just a fyi, depending on what you are shooting. If say you are shooting the moon and you really really want to see that crater, what you do is take a stackload of RAW images and then stack them.

When you do this you are effectively increasing the pixels per area, which means you can zoom in to the section you want and extract it.

This won't work as well tho for DSOs as you are stacking anyways just to get the basic image. Granted i've seen some DSOs where it has been done and there is a decent zoom on it.

[Aeseir]

I forgot to advise that if you are shooting objects such as moon, a video is more effective at capturing the large number of frame which you can then stack and create a gigantic image with a lot of detail.

[wxsatuser]

Eyepiece projection with a Baader zoom EP, Canon 60Da mounted on the EP with the 43mm adapter, scope ED80.

All images recorded with movie crop mode at 60fps.

These were my first attempts but I never pursued this line of imaging and better images could be obtained over time.

Clavius area

Plato

[jimbo747]

Thats a cracking image of Jupiter.

[Daveb3650]

Great pics ...well done..

[Bloosman]

Thanks guys...advice taken on board and monies now spent at First Light Optics....:-)