Good morning! I noticed the manual references 200mm fl for a guidescope in PA. Is there a minimum recommended fl for plate solving in SharpCap? I'm considering a William Optics Unigude 32 with a fl of 120mm @ f3.75. My imaging scope is an ED102 with 714mm fl. Is fl of 120mm sufficient for SharpCap? The 32mm saves me almost 10oz of weight.
Thanks
Rick
Recommended FL for guidescope?
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Re: Recommended FL for guidescope?
Hi Rick,
for polar alignment the 120mm guidescope will be fine. I've actually tested using a 50mm camera lens with a guide camera for polar alignment and had it working.
Of course when you actually guide you will have a little less accuracy due to the shorter focal length, but it sounds like that is a trade-off you are prepared to make in order to save weight. Certainly with a main scope of only ~700mm you should be fine (it might be a different story trying to guide a 2000mm FL SCT using a 120mm guide scope!)
cheers,
Robin
for polar alignment the 120mm guidescope will be fine. I've actually tested using a 50mm camera lens with a guide camera for polar alignment and had it working.
Of course when you actually guide you will have a little less accuracy due to the shorter focal length, but it sounds like that is a trade-off you are prepared to make in order to save weight. Certainly with a main scope of only ~700mm you should be fine (it might be a different story trying to guide a 2000mm FL SCT using a 120mm guide scope!)
cheers,
Robin
Re: Recommended FL for guidescope?
Thanks!! Much appreciated. My first experience with software guiding since original ST-4. Yes, I'm old