FF/FR & SCT star diagonal advice...

[RT65CB-SWL]

Hi guys & girls,

As per the title. I am asking for some advice on... 

1. ...which way round do I fit them if used at the same time with my C6/SCT and/or 're-modded' ETX105?  
2. ...or should I just 'shoot' straight through, (i.e. forget the star diagonal), either with a DSLR or digtal compact camera?
3. ..or would purchasing a 90deg viewfinder for the DSLR be the better option? ...(if "yes!" what magnification. I was thinking of 2.5x-3x).

...as I would like to try a few 'basic' lunar or planetary images.

tnx in adv.

[michael8554]

1) your usual SCT FR has 105mm back focus - the distance the camera sensor needs to be from the back of the FR - so it depends on the optical path length of the star diagonal being used.

If it was possible to mount the FR after the star diagonal your camera would have to be 105mm further away, rather cumbersome and wobbly.

2) Straight through with the correct spacers for the FR has less light-robbing optical surfaces and is more rigid.

3) Do you mean an optical magnifier for the DSLR optical viewfinder ?  Old hat, use the up to 10X magnifier on the DSLR Liveview screen.

Michael

[RT65CB-SWL]

Thank you.

The FF/FR is Celestron and the star diagonal is Altair Astro, with SCT coupling, not 2" pushfit.

15 hours ago, michael8554 said:

3) Do you mean an optical magnifier for the DSLR optical viewfinder ?  Old hat, use the up to 10X magnifier on the DSLR Liveview screen.

Yes. That is the type. Not sure though if my DSLR's, [Nikon D40x & D80], have it. I will re-read the manuals.