Posts Made By: Vincent Bert

Awesome. the full res image looks fantastic.

Very nice! amazing how you captured this so well at such short exposure times. 8O

Hi Louie. I think you used all 66 mm of that scope and got a very nice image! congrats, vince

sure doesn look like it needs any more data at the posted res, very smooth, great colors, all around awesome shot.

Great job capturing all that nebulosity in that huge FOV!

Thats a fine image! Congrats.

Hi Paul, great to see you jumping in with both feet! As far as darks are concerned its generally accepted practice to take at least 10 darks for your exposure time and camera temp then do a median combine to make the master dark for that particular exposure time/camera temp. As mentioned this can be done before you go out and image, just put the camera in the fridge and you can take a whole library of darks for diferent exposures/camera temps in one evening or while you sleep. Once you take the camera out of the fridge make sure you immediatly put it back in the case and close it up so you dont get any condensation on the camera. I genereally make new darks each month before I go out but on occasion have used darks for several months.

With my setup I make darks for 300 sec, 600 sec, and 1200 sec for Ha exposures. I do it at -15C for summer and -20C winter, of course YMMV on operating temps to choose.

Also I have found that you really dont need to image with a camera temp cooler than -20C. I have tried -30C and could not tell a difference in the dark current. On warm nights (75F or so) I can still get down to -15C easily with water assisted cooling. So I generally use either -15C or -20C depending on the season.

Also instead of a median combine for darks and flats I use Ray Gralak's sigma program to make the master frames with outstanding results, and its free.

http://gralak.com/Sigma/index.html

I also use this to combine my light frames with the standard deviation mask as it provides a much smoother image than if using simple median or sum combine. The difference is quite evident when you start stretching the image. Ray has detailed instructions for using this program on his site. Highly recommended.

Also another good resource for figuring how many dark you should take to make your master frames, and a calculator for figuring optimal sub-exposure time for light frames can be found here:

http://ccdware.com/resources/subexposure.cfm

Good luck and look forward to more images from you. Vince

Its magic!!!! Depending on your particular set up youcan almost get by without taking flats and using grad xterminator.

Ivan Ong said:

Hi, any one use Russell Croman's Gradient X Terminator. If so, what is your opinion about it? Thanks very much,
Ivan

Great image of the jellyfish! You did a masterful job of blending the Ha data.

Hi Eric, those Ha shots look fantastic! man I love widefild Ha. Great shots, especially 1499 and 2244. The color came out good to on 405 and 410. I agree, maybe longer RGB subs would have brought out some more of the faint nebulosity, still looks great though, Vince