2" Prime Focus Adapter Help!

[jaskel]

Hi all,

I just got a elim Prime focus adapter for my 400D SLR but I cant get it to focus no matter what I do... can anyone assist as the correct way to set this up?? im new to this so i have no clue! I assume it just goes in where the eyepeice goes and the camera goes on the end, then move the scopes focuser untill u get a focus?

Thanks guys

The one I got is: Elim-T 2" Prime Focus Telescope Adapter for Canon EOS (eBay item 110610318032 end time 11-Dec-10 15:50:21 AEDST) : Cameras Photo

[Cornelius Varley]

I don't think you are doing anything wrong. I suspect that the problem is the telescope. I assume that your telescope is similar to the Skywatcher Skyliner 200P. This telescope, as do a lot of other reflectors, don't have sufficient inward focus travel to allow a camera to come into focus. There are a number of solutions to the problem though.

1. Photograph through a barlow lens. The barlow lens should move the focus point outwards and allow the camera to focus.

2. Move the primary mirror up the tube. You may only need a few millimetres to move the focus point . This can be done by adjusting the collimation screws and theit locking screws.

3. Replace the focuser with a lower profile one - expensive.

Peter

[jaskel]

hmm..ok, would it be better to get a T adapter etc?? Thanks for your advice

[brantuk]

Check the scope first. On my 300P I found a thread suitable for a T-ring on the 1.25" adaptor (about one year after I got it - did I feel a numbnut! lol). The camera now goes straight on the draw tube for a little more inward focus. If you're lucky the 200P will have one too.

[Merlin66]

Jaskel,

A T thread adaptor won't help unless the focus tube is short enough and already has a male T thread on the end. You need about 55mm of inward travel from the normal focus point to position the camera correctly.

I honestly don't know why the scope manufacturers don't take this into account when designing the distance from the main mirror to the focuser...very easily done and none of these issues would arise...

[jaskel]

bummer, I bought the adapter on a recommendation ...looks like ill be returning it...or selling it!

[Shibby]

jaskel, see the black bit on the top? Try unscrewing it from the silver barrel, then remove the EP holder from your focuser and try to screw the black ring from your adapter directly onto the focuser. This will be as close as you can get!