Does anyone know the path length of a SkyWatcher 2" diagonal?

[StuartT]

I can't seem to find a figure online for the path length of my SkyWatcher 2" diagonal.

I want to replace this with extension tubes so I can use my Quark in a linear configuration with a camera. It reaches focus fine with the diagonal so I'd like to get extension tubes of the right length to do the same.

Thanks

[Captain Scarlet]

I have 3 2” diagonals, a Baader, a Revelation and an OEM Skywatcher one. In the past I measured and noted the Baader and the Revelation to be each 107mm. The external extension on the SW can be seen to be the same length as the Revelation one, so my assumption would be that it too is 107mm.

If I get a moment later today I’ll test that theory on a scope for par-focality with an actual eyepiece

Cheers Magnus

 

Edited March 11, 2022 by Captain Scarlet

[vlaiv]

My guess was about 110mm - so pretty much inline captain said above.

[StuartT]

40 minutes ago, Captain Scarlet said:

I have 3 2” diagonals, a Baader, a Revelation and an OEM Skywatcher one. In the past I measured and noted the Baader and the Revelation to be each 107mm. The external extension on the SW can be seen to be the same length as the Revelation one, so my assumption would be that it too is 107mm.

If I get a moment later today I’ll test that theory on a scope for par-focality with an actual eyepiece

Cheers Magnus

 

 

16 minutes ago, vlaiv said:

My guess was about 110mm - so pretty much inline captain said above.

Thanks so much guys!

I hope I can find a 110mm extension 1.25"

[StuartT]

Actually, I remembered that I already have an adjustable extension tube with a 1.25" EP fitting at one end and M42 at the other. So I could arrange this after the Quark (see photo). Would this be ok, or does the extension need to be before the Quark?

 

Edited March 11, 2022 by StuartT

[vlaiv]

11 minutes ago, StuartT said:

Would this be ok, or does the extension need to be before the Quark?

I would put it before quark.

Quarks have blocking filter at the eyepiece side that is limited in size. Further you put sensor - more vignetting you will have from blocking filter (and possibly rest of the assembly).

[StuartT]

21 minutes ago, vlaiv said:

I would put it before quark.

Quarks have blocking filter at the eyepiece side that is limited in size. Further you put sensor - more vignetting you will have from blocking filter (and possibly rest of the assembly).

right. Ok. Thanks