Re: [APML] Rosette comparison (was New Rosette Mosaic)

Hi Rob et al

Just thought you might be interested in a thread on the Starlight Xpress group concerning the Rosette

I don't want to stir up any "x" ccd camera vs. "y" ccd camera debate, or whether film is or is not better with real resolution etc etc.. The comparison was made because one image was taken with a Tak FS60 refractor and the other with a 12.5 inch RC

For those that don't subscribe to that group, I've posted the lead message below.

Just thought some of you might be interested.

Eddie Guscott

PS. FWIW, both Bobby Middleton's pic and yours are excellent. I see too many Rosette shots where the central "tunnel" is red (overprocessing??) and not the same sky colour as that surrounding the nebula. Congrats to you both.

From: "Rick Krejci <randckrejci@y...>" <randckrejci@y...>
Date: Wed Jan 15, 2003 3:41 pm
Subject: Unfair comparison

Just thought I'd make a comparison as to what can be done with top end equipment versus lower end. Rob Gendler, whose work I admire to a huge degree, just posted his beautiful rendition of the Rosette Nebula here: http://www.robgendlerastropics.com/Rosettebigpage.html It's an amazing 9 image mosaic with the top-end SBIG camera and IMG104 with the sweet 12.5" RC scope on an AP900 mount. compare to mine here: http://www.ricksastro.com/Gallery/temp/sxv_rosette_hargb.jpg which was a single HaRGB image taken with the new SXV-H9 with the FS- 60C on a GP-DX mount. While Rob's is obviously much nicer than mine, I was actually surprised at how close mine comes in terms of resolution/detail. The RC's got 10" on the 2.5" FS-60, the ST-10 has about 2.5 times the area and his whole setup has more than $35,000 over mine. And I can't imagine the amount of time put into this, in both imaging 9 separate images as well as creating a mosaic. I had mine processed within an hour after completing the exposures. My point is not to take anything away from Rob's images, they are simply the best around...period. My point is that you can get pretty great results using more modest mounts/scopes/cameras (although you couldn't convince my wife that mine isn't the most expensive setup possible :) ) . Stacking allows less stringent tracking, and as mentioned on a recent thread, helps keep the target signal into the linear zone of the camera (longer single exposure does not always=better when light pollution's involved). The small APO refractors are a great match for the small pixels of the HX916 and SXV-H9. Rick Krejci http://www.ricksastro.com/

----- Original Message -----

From: Robert Gendler

To: astro-photo@seds.org

Sent: Thursday, January 16, 2003 11:39 AM

Subject: Re: [APML] Rosette comparison (was New Rosette Mosaic)

Bobby,

Thank you for posting that. The two images are actually remarkably

similar in resolution and star size. You know Bobby, I'm much more

impressed with your image now that I've seen what the true resolution is.

Its a great shot in all respects. One thing I should mention is that each

frame of my mosaic was only 15 minutes of exposure (luminance) from

moonlit mag 4.0 skies <G>. The color came from an old ST10 image

taken with a 4" refractor. Also the CCD for the luminance is a low res

detector with 24um pixels and not the ST10. Anyway that was helpful and

I commend you on a great image in all respects, color, depth, "AND"

resolution <G>.

Rob Gendler
Email: robgendler@att.net
Web site: http://www.robgendlerastropics.com/

----- Original Message -----

From: Bobby Middleton

To: astro-photo@seds.org

Sent: Thursday, January 16, 2003 6:10 AM

Subject: Re: [APML] Rosette comparison (was New Rosette Mosaic)

Here you go:

http://www.koyote.com/users/bobm/rosette2.htm

----- Original Message -----

From: Robert Gendler

This is easy

to demonstrate if Bobby would post an image cropped like the one below

of NGC 2244 at about 1000 x 1000 res. and a comparison can be made.

http://www.robgendlerastropics.com/RosettebigC.html