Posts Made By: Brian Maynard

Good image Enrico. Nice detail.

Very nice Wes as usual.

Its hard to handle at first. Someone will reply with a more detailed reply but I'll say that basiclly, the color filters are isolating certain wavelengths of light red, green or blue. The CCD registers the light the same it will always be B&W. The software does the dirty work combining the images into a single color image. Then its up to you how much RGB to mix together for the final image. That part is more art than science for the amature. Its amazing how many different colors you can get from the same RGB images. Anyway, no need to rack your brain about how it works, it just does

There's not alot you can do with that I'm affraid. The image is too dim. You need to stack more images to get it brighter. It also looks like the image is enlarged too much or you are a little out of focus.

That is the best deep space image from a web cam I have seen. Great job!

Mark, seems that you've handled the gradient well. What technique do you use? I use the copy, blur, subtract with photoshop but it seems to wash away a lot of star color.

Very nice. Good job

Ivan,
Darks are different from flats. Dark frames remove "noise" from an image that is caused from a heating of the chip from the electronics. A CCD chip is photon sensitive. Since heat and light are the same, a CCD chip can not tell the difference between the two so a dark frame is basicly a picture of the heat being created by the chip. Most software will take a dark frame and subtract it from the images you are taking. It uses the same dark no matter if you take one or a hundred.Darks Must be the same exposure and temperture as your light frames. A one minute light image at -20 must have a one minute dark exposure at -20. Some people will take dozens of darks and average them together and make one single "Master dark."
Flats are different. A flat field is basicly a picture of your telescopes optical path and is used to evenly illuminate the CCD chip. It also removes any images of dust that may show up in longer exposures. Your flats will be at a different exposure and can be at a different tempreture. However since your taking an image of your optics, you MUST be at the same focal plane as your image. If you change your focus the flat will not work. Flats are a little harder to do. You want to saturate the pixels to about 30 to 50% so you need to check your manual to see what the saturation level is. You also need an evenly illuminated surface to image for your flats. Most will use a "sky flat". Taking an image of the sky about 20 minutes after the sun has gone down or comes up.
There are dozens of web sites about both of these that can explain in much more detail. Just do a search for "Dark frames and Flat fields" and you should find everything you need to know.

Thanks for the feedback guys, I really appreciate it.
Mike the only tip I can give you about this camera is the longer the exposure the better. And Joseph, I used an IDAS light pollution filter. Thanks.

Actually, you have a great shot. I have a 2000XCM and I've played around with the processing for a while. I personaly stay away from the DDP. You need a very strong signal for DDP to do any good or, as you already know, things start lookig weird. Stick with the RGB. If need, boost the contrast up as much as possible. Then finish with photoshop or some othe program that lets you adjust the histogram. If your using the Meade 3.3 reducer get rid of it. Its terrible. I recommend the Astrophysics .67. It work perfectly, no vignetting whatsoever. And it cost about the same as Meade's or Celestron.