Yet another go at the Crescent...

[ollypenrice]

I went back to a Crescent done with Yves this summer to compare it with the Jellyfish (they're remarkably similar to look at) and found I really didn't like the processing so I started all over again with it. This version combines HaO111 RGB from the Tec 140 taken with Jordan (JCJC) and the ODK data with Yves. There was no 0111 from the big scope, though perhaps we should get some next year, or at least more from the TEC. (Having just looked at Gendler's image from a 0.9 M scope I can see that the O111 needs a lot more data, prbably over 10 hours. It's the 0111 which catches the diaphanous outer shell which is low tantalizing on his image.) http://www.robgendle...GC6888-BYU.html

Olly

[Mark72]

This came out great Olly,

Would IC443 show the same blue envelope with OIII filter?

Mark

[ollypenrice]

This came out great Olly,

Would IC443 show the same blue envelope with OIII filter?

Mark

Astrophyusically they're not the same, the Cescent being a Wolf Rayet planetary and IC443 a SN remnant but I think it might be worth findinfg out!

Olly

[Gina]

Lovely shot Olly as usual but I certainly see what you mean about the OIII Seems to me that OIII needs quite a lot more exposure than Ha.

[turbotim]

Nice shot!

[AndyEllis]

Very nice shot

[MartinB]

Definitely worth getting more OIII Olly. It's very faint and interesting to compare with Thor's Helmet which is also formed from a Wolf Rayet star and has almost as much OIII as Ha. I found the OIII to be very dim and used that Rod Gendler processed image as a reference, but we're never going to have the data to match that from a skillfully used 9000mm scope! Looking good Olly and with some extra data will see you getting into the realms of the diaphanous

[laser_jock99]

The outer shell on that link looks interesting never seen that before- wish I had a 0.9m scope! Great image BTW- do you think you get all the OIII data?

[sologuitarist61]

Nice shot Olly

[ollypenrice]

The O111 is gettable. You don't need a huge scope, though a very fast F ratio would be nice. Here, at the FL necessary, we have Yves' 14 inch at F6.8 and our TEC at F7. I found 14x20 mins O111 data which I seem to have forgotten about and, by stretching it way past its noise limit, was able to get some sense of the outer O111 shell. This isn't a presentable image, just a test of the principle, but I can't see why the shell shouldn't come within range given sufficient exposure. I stress, this is just a test. Rob Gendler does know a thing or two, though. Playing with this data made me seriously respectful.

It's a great one to work on, though, because until now I've never been able to make any physical sense out of the O111 since it just seemed tp create some strange hard boundaries outside the main nebula. It's weird the way the O111 shell looks as if it's wrapping the Crescent in cling film!

Ay SGLers with an O111 layer at about a metre or more of FL like to combine forces? That would be the way to beat this one!

Olly

[MartinB]

I've got 12x30mins I used for this chappy http://stargazerslounge.com/index.php?app=core&module=attach&section=attach&attach_rel_module=post&attach_id=73074 Happy to share

[ollypenrice]

I've got 12x30mins I used for this chappy http://stargazerslou...attach_id=73074 Happy to share

Hey, that looks like the business, Martin. Let's do a swap. Dropbox?

Olly

[andyo]

A fantastic image.The O111 shell really makes this an amazing object (never seen that before)

[turbotim]

wow! amazing!