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Boötes - Planning a session with the 12"

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"But that's a quiet part of the sky - there's nothing there!" Really? Think again. Here's my chart of the area around Izar for use with the 12". There's so many doubles, we are looking at several sessions to get them all. There's even a couple of long sessions for the 4".


My code:
Yellow - above 50.0"
Green - 10.0" to 49.9"
Orange - 3.00" to 9.99"
Pink - 1.14" to 2.99" (done with the 102mm in mind)
Purple - 12" only
T - 0.6" or below
VT - 0.5" or below
F - secondary below 13.0 mag
VF - secondary below 14.0 mag

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I'll be trying to get some tight ones, if seeing permits. I've previously had Σ1867 in the C9.25. At 0.7" it was an easy split and is to date my tightest double. I'm targeting Σ1937 at 0.6" with the 12"; if I get that, there are several around the map at 0.5" to try. The scope is capable of 0.38", so we shall see.

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Good luck with those! The seeing has been poor for several days here in a row with strong wind and lots of clouds, to the extent that when I see an observing opportunity I just reach for the binoculars instead of my telescopes!

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While that map is great for Boötes, when I came to look at Lyra, there were so many doubles at that scale there wasn't enough space to write the names!

I've doubled the scale for Lyra; what a show that is going to be! It will take me all afternoon to label it though...

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I've decided the idea behind the Boötes map was fine, it just needed a little refining. 

When I look closely at the scale, which is the 20° + 1 scroll in CDC, near the equator an A4 sheet covers 1hr x 10°. So if I arrange the maps by that scale, it works ok up to about 40° where things start to get a little narrow. I'll only label doubles within that 1h x 10° box. I've also labelled doubles beyond the scope with an x so I don't think I've missed some.
I've restricted the doubles to a primary of 10.0 mag and above, and set my minimum separation to 0.6" (T), with my F category being 13.0 mag and below.

The Delphinus map below was a challenge. There's a huge cluster to the right which is packed full of doubles. I've abbreviated CHE to e to fit the labels in. With a modest aperture you could spend a couple of hours just in that spot!


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