Baader Safety Herschel Prism + Vixen ED103 = No focus with DSLR?

[Trull]

Just gotten my new toy - the "P" version, fitted it to my ED103 and checked it visually with Ethos13mm. Sun looks lovely. Then I fitted my Canon 20D with MaxDSLR 2"nosepiece and I can't achieve focus, it wants to be closer than I can push the focusser!

Has anyone else had this problem?

I'm aware that some Takahashi refractors have this issue - but I wasn't aware that the Vixen would too. Any suggestions?

[iwatkins]

Yep, ditch the 2" Click-lock adaptor and nose piece and replace with the Baader T-ring adaptor and a Canon T ring. That lot will scrub about 30mm from the image train.

If you still struggle, a low profile T ring for the camera will scrub another 10mm.

See page 10 of the manual here: http://www.baader-planetarium.uk.com/en/pdf/HERSCHEL_PRISM_MANUAL.pdf

Part No. 150-8035

Cheers

Ian

[Trull]

Thanks Ian, adaptor ordered!

[iwatkins]

No worries

When it arrives, your Canon specific T ring fits one side and your stack of filters screws in the other. You then unscrew the 2" Click lock and the screw in tube that currently holds the filters. Your new stack then screws in top of the wedge.

In the picture below I have a DMK41 and a Baader T to C mount mounted onto the same ring you have just ordered, so you can see how much in focus you'll gain.

Cheers

Ian

[Trull]

Looks plenty, I have a DFK21 which will be getting the same treatment as your DMK41 shortly. I tried unscrewing everything - and its just as you described and all as per the manual.

Have you tried a Calcium K line filter?

[iwatkins]

I haven't yet, no.

But once I get the hang of this system (I've only had my wedge a few weeks) it's something on my list.

Cheers

Ian