More Matched Doubles In Delphinus

[cloudsweeper]

Delphinus is a good region for matched doubles. Of the ones planned, the greatest difference in magnitude is 1, meaning that the primary is 2.5 times brighter – not a huge difference, considering that a magnitude difference of 2 indicates about 6.3 times the brightness, and for 5 it’s 100 times!

Quick collimation check of the Bresser Dob – spot on. Caught a ‘plane passing – managed to focus and track it for a few moments. Then spotted Vega at 7.20 – that’s more like it time-wise!  Before serious observing, I enjoyed the beautiful sight and sound of thousands of geese overhead, then the usual twilight bats swooped and darted above me.

I reported recently on the Delphinus Double Double, comprising Gamma Del and Sigma 2725 – both easily split at x64. But now for some new targets:

Sigma 2703 – matched double, 25” - from Rotanev to a small triangle of stars, the two closest being this target. Very easy.

Sigma 2701 – close match, 2.1” - from Aldulfin this was easily found, taking AV and x127 to split it.

Sigma 2718 – very close match, 8.4” - not far from the above, just split at x35, clearer x64.

Before trying for a few more, I did a quick diversion via Enif to the Globular Cluster M15 in Pegasus – small and fuzzy at first, better x127, then with some stars resolved out of the dense mass at x159.

Further progress in Delphinus was thwarted by cloud, but it was a successful and enjoyable couple of hours.

Doug.

 

 

 

[mark81]

Nice report on doubles there,  very interesting how many varieties there are.  I have been enjoying the many easier doubles with the st80 and when I eventually upgrade I will certainly buy with Doubles in mind.. 

[cloudsweeper]

4 hours ago, mark81 said:

Nice report on doubles there,  very interesting how many varieties there are.  I have been enjoying the many easier doubles with the st80 and when I eventually upgrade I will certainly buy with Doubles in mind.. 

Thanks Mark.  All my 'scopes do well with doubles.  A bigger aperture would help you with tight ones, and on a good frac would perhaps also help with nice, sharp images.  There's certainly plenty to enjoy in this topic!

Doug.

[Special K]

That’s a handy list of doubles I must try for. Small constellation too!  I had a look at M15 the other night and it sure is dense. Nice one!