Comet C103p/Hartley in Perseus Oct 13, 2010 50% pixel view
click the image for a 100% pixel view or HERE to return to the index page

More time on the green comet, 20 minutes of comet combined with 80 minutes of background. The tail is becoming easier to see, rather image,
but it takes at least a few four minte exposures to bring it out. I had planned 100 of the comet, but, if you look closely in the larger image,
you can see a star right next to the nucleus... bad news for the guider which I had left unattended... Obediently, the guider
took off after the star.. and did quite well actually, giving me 80 minutes .. LOL

Processing on these subs was tricky. I first did a standard deviation stack of the comet nucleus, and then a standard deviation stack of the
background aligning on the stars. I cleaned up the star trails in the comet stack, and combined that with the star stack using "lighten" in
photoshop. I used curves to stretch the comet a bit, and the spotting brush to clean up residual star junk...
Carboni's tools made the stars a bit more colorful and a final density adjustment was applied on the end stack with Photoshop...

simple, no?

Telescope	Explore Scientific David H. Levy Comet Hunter Maksutov-Newtonian 152mm f/4.8 mounted piggyback on Meade LX 200 Classic 12 inch
Camera	Canon XT/350d modified with Baader type 1 filter by Hap Griffin
Exposure	twenty 4-minute sub-exposures guiding on the stars, and five 4-minute sub exposures guiding on the comet, all at iso 800
Guiding	PHD Guide from Stark labs with Meade DSI pro I on Meade 12-inch LX 200 Classic at f/3.3
Software	Images acquired, calibrated, stacked and color corrected with Nebulosity 2.3.3 from Stark Labs. Further processing in Photoshop CS 3.
on-line links to more information	for more information try a google search for the comet.