Baader Hyperion can't reach focus on Moonlight CR2?

[Peje]

As title,

I used the Hyperion without any trouble on the stock focuser but when I upgraded to the CR2 (38mm) I now can't get focus. I'm pretty certain this is because I haven't got enough travel to get far enough back. I just wondered if anyone else had seen this, and if so, what length extension tube did you use?

I have some extensions but not sure if they'll be long enough so wanted to get a feel for what others are doing before I go ordering parts.

Pete

[John]

Hi Pete,

Are you using the 1.25" barrel of the Hyperion or the 2" section of barrel ?

If you use the 2" section, this in effect moves the focal plane of the eyepiece inwards quite a way which means that you would need to rack the focuser outwards by a corresponding amount and you might run out of focus travel ?

Another point is that the Orion Optics newtonians generally have their focal plane well outside the tube wall. When I fitted a Moonlite focuser to my Orion Optics 12" I needed to use both the 1 inch and .5 inch spacers as well as the fitting plate to get the focuser to the correct position where all my eyepieces would come to focus.

[Peje]

Hi Pete,

Are you using the 1.25" barrel of the Hyperion or the 2" section of barrel ?

If you use the 2" section, this in effect moves the focal plane of the eyepiece inwards quite a way which means that you would need to rack the focuser outwards by a corresponding amount and you might run out of focus travel ?

Another point is that the Orion Optics newtonians generally have their focal plane well outside the tube wall. When I fitted a Moonlite focuser to my Orion Optics 12" I needed to use both the 1 inch and .5 inch spacers as well as the fitting plate to get the focuser to the correct position where all my eyepieces would come to focus.

I'm using the 1.25" section for that very reason!

I'm almost certain when I originally fitted the CR2 (using all the spacers) I was able to see the lens in focus when I manually held the len above the focuser, unfortunately to get my DSLR to focus I had to remove these adaptors.

I think I might be looking at 3" or so of spacing to get focus, my main reason for starting this thread was to make sure this was correct..which it seems to be!

[Peje]

John,%2

[John]

I'm using the 1.25" section for that very reason!

I'm almost certain when I originally fitted the CR2 (using all the spacers) I was able to see the lens in focus when I manually held the len above the focuser, unfortunately to get my DSLR to focus I had to remove these adaptors.

I think I might be looking at 3" or so of spacing to get focus, my main reason for starting this thread was to make sure this was correct..which it seems to be!

In which case I think you will need to use an extension tube. I needed one when I 1st got my 12" Orion Optics because it had a low profile focuser for imaging. I only use it for visual. I found that both 35mm and 50mm extension tubes worked OK with the 35mm one suiting my eyepieces a little better.

This Moonlite one might be worth considering:

http://www.firstlightoptics.com/adapters/moonlite-15-focus-extension-tube.html

[Peje]

In which case I think you will need to use an extension tube. I needed one when I 1st got my 12" Orion Optics because it had a low profile focuser for imaging. I only use it for visual. I found that both 35mm and 50mm extension tubes worked OK with the 35mm one suiting my eyepieces a little better.

This Moonlite one might be worth considering:

http://www.firstlightoptics.com/adapters/moonlite-15-focus-extension-tube.html

Got it to focus with a bit of buggering around but  something just isn't right...when I focus with no camera attached to the end of the eyepiece the image is beautifully detailed. When I attach the camera directly to the end of the eyepiece and readjust the focus the best i can get is pretty awful. (I'm using Backyard Nikon to measure the focus value to be totally sure). Yes I can see the surface but it's nowhere near as crisp.

Am I right in assuming that because it's fine without the camera that it means there's something not right with the junction between the eyepiece and camera? Currently all there is :

Nikon Body

Nikon T-ring adaptor

Hyperion T-" Adaptor with small rubber ring

8mm Hyperion Eyepiece

It strikes me that it's as if I'm missing something in there