Help on converting Finder to guide scope

[krobbo]

Hi again! 

So here's problem 656 so far (feels like it trying to get this gear to work!!).

I'm trying to convert a 9x50 finder for guidescope use? I've a Celestron & Skywatcher finder. I've bought the correct step rings & a Baader Helical focuser thinking this would do the trick?

Nope!!

I've tried using a 25mm Plossl in the back & I've a QHY CCD guide camera but the focus point is well inside the main finder tube?

 I've taken the back off & manually moving the eyepiece in there is a huge difference between the two focus points. With the Baader on there's no way of getting anywhere near the focus. It's going to go on a new ED80 PRO hence the Skywatcher 9x50, gutted it doesn't work! 

Throwing good money after bad, I'll be gutted if I've got to but another guidescope setup, I've tried searching the forums on here but can't seem to find the answers??

If there's anybody on here that can help I'd appreciate it !!

Your faithfully, Battered Head !

[MARS1960]

When i converted mine i had to find a 5mm adapter to screw into the finder to screw the camera into, any longer and it wouldn't work, thx to an SGL member, Bernard at modern astronomy stocks them.

[krobbo]

Cheers for the info Mark I was hoping to use it as a finder & guider combo by switching between eyepiece & camera, looks like it's not feasible?

 

[MARS1960]

6 minutes ago, krobbo said:

Cheers for the info Mark I was hoping to use it as a finder & guider combo by switching between eyepiece & camera, looks like it's not feasible?

 

It is possible, i just unscrewed mine in a couple of seconds and could easily pop the eyepiece back in, here's a pic, the little screw thread thingy screws right inside the finder so you can get focus but when you take it out it always unscrews from the finder and not the camera so it doesn't get stuck in there.

[krobbo]

Is this the adapter you bought from modern astronomy mate? Found a few threads online and the norm seems to cut down the finder tube assembly and re- thread it  great If you've got the gear to do it! 

[MARS1960]

Yes mate, 5ml, It's the only place i know that sells them, works a treat, dead cheap and better than getting the hacksaw out .

[JimT]

I have a few of these spare and have converted them to take a camera, the bit you may not have done yet is to unscrew the front off, the lens piece and the ring.  Once off turn the ring around and screw back on and then put the lens piece back on as normal, screw both in all the way, you will find that you get that extra bit down which will give you focus.  It will be trail and error, turn the lens part back up and focus will be achieved, turn the ring back up to the lens piece to keep all in place, good luck.

Jim

[krobbo]

Hi Jim & thanks for the info. I spoke to Steve at FLO & I think he's hit the nail on the head. The trick seems to fit the lens element off a 2X Barlow lens into the path before the eyepiece/camera. I've tried this (you have to unscrew the lens part of the Barlow off the eyepiece adapter) & focus can be achieved. I just need to make a push fit adapter to fit the barlow element inside the rear of the finder scope then I can fit the helical focuser. Should be able to achieve focus with a camera & an eyepiece with this set up!