Orpington Astronomical Society

Astronomy => Astrophotography => Topic started by: Fay on Jan 22, 2010, 09:39:28

Title: M45 180110 17x300
Post by: Fay on Jan 22, 2010, 09:39:28
This image is no good, I was not going to post it. It was really a test image. Uncropped as far as I can remember, unless there  was a very slight one due to mis alignment.

Taken 180110, Canon 350D, ED80/ 0.85fr,17x300secs, internal cls

I have put it on as it is the first time I have used the dedicated 0.85 focal reducer for the Canon/ ED80.

The flats were no good, as I was having problems with programs, & gave up. The edges & corners seem to be ok.

(http://farm5.static.flickr.com/4022/4294442017_909547a467_b.jpg)
Title: Re: M45 180110 17x300
Post by: Mac on Jan 22, 2010, 15:45:56
QuoteThe edges & corners seem to be ok.

yup, you seem to have these blueish / whitish blobs in the middle.
as well as this larege speclly white pattern :cheesy: :lol:

Looks ok. you can just start to see the nebulosity coming throught.,
Title: Re: M45 180110 17x300
Post by: MarkS on Jan 22, 2010, 16:15:48
In the images I've done with the Canon on the ED80 with the William Optics reducer I've found that one or more of the colour channels was mildly defocused.  It doesn't show too much in the full colour image though, except that the H-alpha regions are less sharp.

Try splitting your image into RGB planes and see if they are all equally sharp - mine were not.  I'll probably end up getting the proper ED80 reducer now it's available (assuming it is better!)

Mark
Title: Re: M45 180110 17x300
Post by: Fay on Jan 22, 2010, 16:37:43
I could not get any more out of this, it was an exceptional dewy night,  I was surprised not to get any more nebulosity out of it.

I split the channels but it was difficult to see if one colour was more focused than another. I will have a look on an individual sub