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View Full Version here: : C11 Microfocuser and Rack & Pinion Focussing


stefang
14-01-2015, 05:53 PM
Hi there,
I currently have a CPC 800 with a Starlight FeatherTouch Micro-focuser which i love. I recently also acquired a C11 CGEM as well and am looking to upgrade the stock focuser with a Starlight FeatherTouch as well.

I have read a couple of threads both here and CN about SCT users installing both Micro-focusers and Crayford Rack and Pinion Focusers as well directly on the SCT visual back.

As a relatively new astronomy student, does the R&P focuser negate the need for the standard focusing assembly? Am i correct in assuming that if both are installed, initial approximate focussing is undertaken with the secondary focuser and then fine tuned focusing undertaken with the Crayford R&P as its not directly bending the secondary mirror assembly?

Is this correct or am I on the wrong path?
Many thanks for any assistance.
stefan

casstony
14-01-2015, 06:21 PM
If you buy the Crayford there's no need to replace the standard focuser - rough focusing is done with the standard focuser then the Crayford is used for final focusing. If you get a feathertouch Crayford I'd recommend the 0.8" travel model which chews up the least back focus.

Merlin66
14-01-2015, 08:39 PM
Stefan,
I've used the Feathertouch 10:1 micro on both my original C9.25 and the current C11.
It works extremely well. IMHO there is no need to add anything else.

Camelopardalis
15-01-2015, 10:07 AM
+1 for the Feathertouch...works really nicely on my C11.