st80 qhy5

Using SharpCap's Polar Alignment feature
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Joined: Sat Jul 22, 2017 7:02 pm

st80 qhy5

Post by MarkH » Sat Jul 22, 2017 8:36 pm

Hi All,

I have had some success in the past but last night I tried to use polar align with my st80 and old qhy5 mono. After lots of tries only once did it solve the first image but refused to resolve the second. Other than than I would just not solve.

I tried lots of setting but failed and gave up. I really want this to work.

If anyone can help me with settings that would be really helpful.

At the moment it seems the uk is shrouded in constant cloud so I am limited on test time.

I have seem that increasing my star size to 4 may help but I will not know until I get another clear enough night.


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Location: Vale of the White Horse, UK

Re: st80 qhy5

Post by admin » Sun Jul 23, 2017 2:42 pm

Hi Mark,

Some people have had success with this combination, but it may depend on a little luck in starting off in an area with a relatively rich star field.

I would generally suggest that the starting point should be max (or near max) camera gain and 2s exposures. Then try the digital gain option or slightly longer exposures if not enough stars are being selected. If hot single pixels are being detected as stars then try increasing the minimum width.

Also, make sure you are within 5 degrees of the pole when starting or it just won't work!

If none of that helps then make sure you save some frames (use the snapshot button in SharpCap) and share them here so I can see if there is anything obvious wrong. It's also not a bad idea to try plate solving one of the saved frames at - if that fails then it's unlikely that the SharpCap plate solving can be made to work (and if it works but gives you a dec of 85 or less then you know you are further than 5 degrees from the pole).

The final option would be to consider a 0.5x focal reducer to give a wider FOV - these can be bought in 1.25" filter thread fitting from various suppliers.



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