View Full Version : M-16 Nebula

Terry Johnson
10-15-2014, 11:47 AM

Hello, this image was taken years ago. It is composite of 80 images taken with a Santa Barbara Instruments ST-10, 6-meg, water-cooled, dual-chip camera. One chip is for guiding the equatorial telescope mount, the other is for taking the images. The lens used was an Astro-Physics 750mm, 5 inch, F5.6, telescope. The camera is special in that it is a B&W camera using color filters. To reduce noise brought on by heat in the camera, the camera is water cooled and images are stacked using special astro software.

Your comments please...Terry Johnson:S3:

Don Railton
10-15-2014, 06:49 PM
Hi Terry

Very impressive...I like that some of the stars are large and obviously round, a result of the sophisticated tracking no doubt.. Does "6 meg" means a 6 megapixel sensor?? If so, I wonder what this image would look like on todays sensors...


Andrew McLachlan
10-16-2014, 07:55 PM
Hi Terry, I think Don nailed it with his first two words...VERY IMPRESSIVE!!!

Diane Miller
10-17-2014, 08:38 PM
Simply gorgeous and stunning, with sharp detail and low noise! I'm new to astrophotography, but from what I've gathered, 6 meg is a very robust sensor. Not a regular camera but a dedicated CCD sensor. Terry -- fill us in!

What would be the equivalent focal length in terms of our full-frame cameras?

I'm still puzzling over stacking software, and using my Canon 600mm II and an Astrotrac -- can't see getting a telescope at this point.

Dvir Barkay
10-18-2014, 02:25 PM
beautiful shot of the Eagle Nebula, I love astrophotography, but haven't been able to do it in a while because of other photographic work. Really well done, and excellent image. Maybe if one nitpick is the stars could be a bit more pinpoint, and maybe the blacks just a tad blacker. Amazing though seeing the pillars of creation in there, even more amazing is that they technically don't exist anymore ;)

Terry Johnson
10-18-2014, 04:27 PM
Diane, it is not necessary to use a telescope to get good images of celestial objects...Stars, planets, nebula, star clusters, galaxies. However, I say this only if you are using high-end, large aperture, Canon, Nikon, etc lens. You can get panoramas and the moon without using a mount. Once you start taking images of night sky objects with exposures over 4 or 5 seconds using a large telephoto lens, you will get elongated stars and blurry images. The only way around this is to use a quality telescope mount. With most quality mounts you can purchase camera attachment hardware for the major DSLR cameras. Once you have this configuartion you can get some wonderful images with DSLR cameras. You will also need some astrophoto software specifically for stacking and processing the images. These products allow you to automate your imaging sessions and help in the processing of images by reducing the noise accumulated while taking long exposure DSLR images, ie, 10 to 20 minutes per image.

The scope I was using for the M-16 image was equivalent to a 750MM F5.6 camera lens...Terry Johnson

Cheryl Slechta
10-18-2014, 05:25 PM
Astrophotography is mind boggling to me but this is very impressive!

Morkel Erasmus
11-04-2014, 05:08 AM
Sorry for only commenting on this one now, Terry. VERY cool shot, really digging it!! I found your explanation of the gear and techniques used intriguing as well. :cheers: :5