April 27, 2010

M92 (4-14-10)

M92 is a globular cluster about 26-27,000 light years away in the constellation Hercules. Visual observers often look first for the great globular M13 in that constellation, as it is brighter and larger (it is closer). M92 appears more compact to me, but it too, like all its cousins, is a stunning sight.

This is another shot with the SXVF-H9C and the AT8RC, taken just before the M39 image. This is 17x5'. Bias subtracted but not flats (if you stretch this image you will see the dust donuts; I don't have a rubber band large enough to tie a t-shirt around this scope yet). Like M39, this image too has a bit of collimation or guiding error; I'm not sure which. Compare this image with my last image of M92.

M39 (4-24-10)

This is M39, or most of it. The brighter stars in the image are members of this open cluster in the constellation Cygnus. This image was started around 4:40 am on the morning of 4-25-10. The sun was going to come up (my last worthwhile exposures were taken around 5:47), so it was time to hurry and find one more object to image. A bright open cluster was an ideal target. The cluster is larger than what you see here, but it spilled out of the field of view.

This is 62x60" taken with the SXVF-H9C through the AT8RC. Capture and preprocessing was done in Nebulosity 2 and touchup in Photoshop CS3. Bias frames subtracted; no darks; no flats. The moon was 80+% full. Collimation (or possibly guiding, I suppose) was still just a touch off, but this is a colorful, quite usable image nonetheless. If I let perfection get in the way of enjoying the images, I'd never have taken any.

April 11, 2010

Another M101 (4-8-10)

M101 is an enormous galaxy just 27 million light years away in the handle of the Big Dipper. It is 170,000 or so light years across. It is so large that it distorts nearby galaxies, and it is so far-flung that pieces of it seem to be dragging behind it. What looks like a small piece of M101 at the bottom of the image is actually considered a separate galaxy, NGC 5477, but very deep images of M101 (such as this one by R Jay GaBany) show longer and more tenuous spiral arms swirling out beyond what you see here.

This image is a bit better than the one taken a few weeks ago. This is 43x6' with the SXVF-H9C, through the ED80 and WO 0.8x II ff/fr. An IDAS-LPS-P2 filter sat between the fr and the camera. Bias and T-shirt flat frames applied; no darks. Capture was done in Nebulosity 2 and guiding with PHD through the AT66ED on the EM-10. Pre-processing was done in Neb 2, stacking and most post-processing in Maxim, and much touch-up and color work in Photoshop CS3 with the use of an important Carboni action. Thanks to Jim Wood for editing tips.