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Hi all

Here's a couple more shots from Monday's session. 
First, the rather faint Hickson compact group 34 in Orion, a chain of 4 galaxies in the centre of the image. The brightest is NGC 1875 at mag 14.6 and looks stellar. The other three are falling off to the west/south-west and range in magnitude from 17.5 to 18.4 as shown in the figure. The sensitivity of the X2 mono is evident here.
Second, something that has been on my hitlist for a while: Abell Galaxy Cluster 539 a few degrees away from the Hickson group. This 50-strong cluster at around 470 M light years is doubly interesting since it contains a lovely galaxy chain, VV161, at its centre. 
The accompanying pdf provides details of all the galaxies and the wider field. The VV161 galaxies are numbered. 
This chart is part of a new project I've been working on during the overcast nights of the last few months: developing from scratch a new deep atlas suitable for EAA. I hope to release a first version in early March (probably focusing on Virgo and Coma) in time for galaxy season.
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Hi Martin,

Excellent work! I was happy to see you got yourself the LSX2 mono. I figured we would start seeing some of your great presentations of distant galaxies with it.

I'm going to try to get Hickson 50 next time out. Your work always inspires me.


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Thanks Paul & Nathan. The original mono would go a little less deep in the same exposure time but I suspect it would be less than a magnitude different. With 45 or 60s exposure I imagine it would go as deep. My Lodestar-C is the original version which is less sensitive than the original mono and I've managed to go beyond mag 18 with that too.

Much depends on the skies. Although there was no moon the sky was quite bright due to reflected light from the snow I suspect. I'm hoping to get down to mag 19 with the Quattro+LodestarX2 at some point….


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Hi Mark

In principle, yes :smiley:. When I prepare the Virgo-Coma maps in March I'll sort out a mag15 version too. The main difference is in the FOV, which can be somewhat larger for each mag15 chart, although I may have to adopt a different map projection if it gets too wide in order to minimise distortion.


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Nice HGC 34 in Orion Martin - well done. It's surprising that N1875 is so much brighter [and larger] than the remaining trio but all have similar RV and distance.  Tried for it tonight but thin cloud intervened but will post under my 'B33' thread and repeat sometime.  Wikisky shows brighter mags for gxs than Megastar [=close to yours] - so much variation :police:  

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Thanks Nytecam. Mine are directly from the LEDA catalogue so supposedly up to date whatever that means.

Now, if you're looking for variation then distance estimates to PNs are the thing….Martin

Thanks Martin - LEDA leads and trumps others cats !

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