An update on photographing all NGC objects

[rogerg (Roger)]

G'day all,

I've been continuing to make progress with photographing all the NGC objects visible from my location. I haven't been finding the time to prepare any for display on the web or transfer to fellow astronomers who have requested them, so no actual photographs right now (hopefully some day soon). But I do have an updated scatter graph showing the coverage I have so far. I have 747 photographed now. I've photographed more, but cull about 5 out of about 60 taken each night due to various factors.

It's become quite easy to run the project. The other night I was trying to get TPoint working and doing some long exposure shots of a cluster of galaxies, 10 minute exposures. The exposures were turning out perfect but scripting of it just wasn't working because of my tiny guide chip. So I took the slack option of going back to photographing NGC objects and was up and going in 15 minutes flat. Very nice.

It's good fun, and nearing almost 1/4 the way through observable NGC objects from my location, completion is looking quite achievable now.

Soon I'll have to start thinking up a new project to keep myself busy Oh wait, I could just take normal astro photo's... no, surely not..

The attached graph shows distribution of objects across RA & Dec. Earlier in the project I was taking images across the full Dec range each night, where as now I work from south to north. So that's why the graph is shaped as it is, wider patch (more even distribution) where I started, and more dense narrow distribution where I'm currently progressing through.





Roger.

[renormalised (Carl)]

Interesting graph....I wonder if it has any statistical significance with regards to the distribution of objects in the sky?? Would be interesting to find out.

[allan gould]

This will be a great resource when you manage to complete it. Hope progress goes well

[rogerg (Roger)]

Originally Posted by renormalised

Interesting graph....I wonder if it has any statistical significance with regards to the distribution of objects in the sky?? Would be interesting to find out.

Yes... I think it would, if it were complete. Right now, the distribution is mis-leading because I have changed my "scanning pattern".

It'll be very interesting when complete to have a high res graph so you can see "strands" of galaxies and the like, I think.



Of course the complete graph could be generated right now without any observations, just using data extract from TheSky, but that's not the point

[Ric]

That would make your project roughly 10% completed. Your progressing at a good rate by the looks of it.

Top stuff Roger

[rogerg (Roger)]

Originally Posted by Ric

That would make your project roughly 10% completed. Your progressing at a good rate by the looks of it.

Top stuff Roger

10% if I could see all 7900 odd objects My telescope can only physically photograph about 4000, maybe up to 4800. So much better than 10%

[renormalised (Carl)]

Originally Posted by rogerg

Yes... I think it would, if it were complete. Right now, the distribution is mis-leading because I have changed my "scanning pattern".

It'll be very interesting when complete to have a high res graph so you can see "strands" of galaxies and the like, I think.



Of course the complete graph could be generated right now without any observations, just using data extract from TheSky, but that's not the point

Have you come up with an algorithm to account for selection bias caused by the change in scanning pattern???. It might pay to try and come up with one, so that the graph can be corrected for it.

[rogerg (Roger)]

Originally Posted by renormalised

Have you come up with an algorithm to account for selection bias caused by the change in scanning pattern???. It might pay to try and come up with one, so that the graph can be corrected for it.

No, I'm not sure why I would? The point of the scatter graph is to show actual position/distribution in the sky of photographed objects, any algorithm would surely affect that and hence not give a true representation of the currently recorded objects positions?

Anyhow, I intend to finish the whole scan so the graph will be 100% complete and hence scanning pattern will be of no consequence . Spare time I have generally tends to go into improving the algorithms associated with object selection and the automation process of creating scripts and processing images.

Thanks,
Roger.

[rogerg (Roger)]

Here's 3 galaxies from last night. Each is 10x30 secs:

http://content.rogergroom.com/cms/000884.jpg
http://content.rogergroom.com/cms/000885.jpg
http://content.rogergroom.com/cms/000886.jpg

Roger.