Binning during PA

Using SharpCap's Polar Alignment feature
Post Reply
epdreher
Posts: 2
Joined: Mon Jul 09, 2018 7:38 pm

Binning during PA

#1

Post by epdreher »

I downloaded and purchased the Pro version yesterday to hopefully replace my Polemaster procedure.

My guide scope has a 330mm FL. With a QHY5L-II, the FOV is approximate 0.83 x 0.62 degrees which, from what I've read, will work for polar alignment. My question:

If I bin at 2x2 which effectively doubles the FOV on both axes, does this actually translate to a wider FOV, making it easier to obtain the needed stars?

I'm living in thunderstorms right now and haven't had the chance to try the software yet, so I'm looking at all aspects.

Thanks for your answers.
User avatar
admin
Site Admin
Posts: 13271
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: Binning during PA

#2

Post by admin »

Hi,

unfortunately binning doesn't increase the FOV of your camera - you just see the same area of sky at a lower resolution. It may help find stars because of the increased brightness (or reduced noise) that binning gets you.

Please send some of your thunderstorms this way - we have had no rain for weeks and could do with a good downpour!

cheers,

Robin
epdreher
Posts: 2
Joined: Mon Jul 09, 2018 7:38 pm

Re: Binning during PA

#3

Post by epdreher »

So the math isn't always correct when it comes to FOV calculators. ;)

As to the thunderstorms, you can have them. This is the worst six months we've seen as far as astro-skies are concerned. Even when there's no rain for weeks, the clouds just play havoc with our observing conditions.

Thank you.
User avatar
admin
Site Admin
Posts: 13271
Joined: Sat Feb 11, 2017 3:52 pm
Location: Vale of the White Horse, UK
Contact:

Re: Binning during PA

#4

Post by admin »

What I thnk the FOV calculator may have missed is that if you bin 2x2 then you double the pixel size (say 3.75 to 7.5 micron) but you also halve the horizontal and vertical pixel count of the image (say 1280x960 to 640x480). The net effect is that the FOV stays exactly the same :)

cheers,

Robin
Post Reply