M20 Big and Beautiful

Hagar (Doug) · #1 31-05-2009, 11:34 AM

With the sale of the FS102 I again mounted the Vixen VC200L without it'f focal reducer.(FL = 1800mm) I thought I might take a quicky of M20 to compare to the wider field shot a couple of nights back with the FS102 and reducer.

This is a compilation of 9 X 10minute images, 7 used for the stack in Images plus. Darks flats and bias files used in the calibration process.

Both these are the same image and both reduced in size using PS CS2 web image. The second image has had the histogram moved to the right prior to resizing as web image seems to clip the black point during the shrinking process.

Hope you enjoy.

TrevorW · #2 31-05-2009, 02:25 PM

Doug is this cropped

Hagar (Doug) · #3 31-05-2009, 02:59 PM

Full frame, only the oversampled edge removed.

bluescope · #4 31-05-2009, 03:10 PM

Number two definitely brings out the reflective neb better ....

Peter Ward · #5 31-05-2009, 04:28 PM

Doug....the stars are bloated in this one.

CCDInspector says the FWHM is around 8 arc sec....bad seeing? or maybe the focus was a bit off.

Nicely guided though.

Stick with it

Hagar (Doug) · #6 31-05-2009, 08:32 PM

Quote:

Originally Posted by Peter Ward

Doug....the stars are bloated in this one.

CCDInspector says the FWHM is around 8 arc sec....bad seeing? or maybe the focus was a bit off.

Nicely guided though.

Stick with it

Thanks for the comments Peter, I have a copy of CCD Inspector and have some trouble understanding the figures given considering the difference between say the final Tiff image and the size reduced JPG image. Using the figures I believe to be correct for my camera and scope I get quite different figures and as I say different between Tiff and JPG image. FWHM = 5.2.

The seeing here is very rarely good. Living in the bottom of a valley surrounded by quite high mountains only about 4 km away makes for quite a bit of atmospheric turbulence. The best imaging time here seems to be about 3.00am but not my best time for sure. The other problem with this image was my own wood fire blowing smoke overhead during the imaging session.
Things I just have to live with.
I still enjoy the whole deal and love the final results even when not the best I've seen.

Alchemy (Clive) · #7 31-05-2009, 09:04 PM

go get em doug, nice Rooooouuuund stars, looks fine to me

clive

Hagar (Doug) · #8 01-06-2009, 01:11 PM

Thanks Clive, The round stars were somewhat a surprise to me as the guiding seemed to be all over the place. I had trouble keeping the RA line within the first grid line above and below the middle in PHD.