Image of the day

Captured by
Philip Imbrogno

Jupiter

About Astromart

My Account

New to Astromart?

Register an account...

Need Help?

Posts Made By: Andrew Riehl

December 15, 2002 05:44 PM Forum: Equipment Talk

Base mounting screws for Nexstar 11 GPS

Posted By Andrew Riehl
If memory serves me correctly from when i replaced mine, they are 3/8"-16 tpi. Best to take your current bolts to the hardware store and confirm. If anyone else can correct me, please do. Be very careful not to screw to far into the base, BAD things will happen if you punch through to the other side.

December 22, 2002 07:34 AM Forum: CCD Imaging and Processing/Solar System

A not so ordinary look at m33...

Posted By Andrew Riehl
Here's the raw image (after flat fielding and dark subtracting). Note the huge light pollution/lunar gradient, along with some dark spots that didn't flat field out for some reason. I'm really proud of the magic I was able to work for the final image. Thanks for all the great processing info in your book ron.

December 29, 2002 06:54 PM Forum: Film Astrophotography - Imaging and Processing

Taking the Hartmann Mask another step forward?.

Posted By Andrew Riehl
Not much to add on this except one little thing that may be corrected by someone more knowledgeable in optical design. If, you were able to get the holes to be an exactly identical size, I'd think you would still need absolutely PERFECT collimation to get the cancelling effect also seeing conditions would probably fluctate it. It would be probably easier to use a knife edge/ronchi focuser (which has pretty much the same effect) or use a mask with holes that introduce diffraction spikes (i.e. triangular). centering the diffraction spikes is a lot easier. My thoughts.

December 31, 2002 09:30 PM Forum: CCD Imaging and Processing/Solar System

Interesting Jupiter Feature..

Posted By Andrew Riehl
very neat. Kind of looks like a duck...

January 10, 2003 10:42 PM Forum: Film Astrophotography - Imaging and Processing

Orion

Posted By Andrew Riehl
ah yes; beautiful image. I love film for it's huge field of view and ease of use. I use it whenever I can (which is very little). New Mexico is one story, but try taking such an image from a very light polluted suburban back yard. This is where film is useless, yet the ccd will still allow you to image. Each definately has its place. When I get to a good sky, I take film. 330 other days of the year, I'm ready to go with my ccd.

January 11, 2003 09:21 PM Forum: Equipment Talk

Making larger SCT's mobile

Posted By Andrew Riehl
well, the 11" celestron weighs almost 15lbs less than the 12" meade, (almost the same as the 10" meade)and also the 12" meade costs a few hundred dollars more with the optional coatings you need to match the celestron's which are standard. There are a million pros and cons which could justify the choice either way, but these would be the ones which would concern you the most I believe.

January 12, 2003 10:12 PM Forum: CCD Imaging and Processing/Solar System

moonshot redone...

Posted By Andrew Riehl
this is a single frame from the stack, processed with exactly the same sharpening numbers as the stacked one above. Note the extra grain

January 14, 2003 01:41 AM Forum: CCD Imaging and Processing/Solar System

another preliminary...M81--big pic

Posted By Andrew Riehl

January 16, 2003 11:55 AM Forum: Equipment Talk

Color Filter Wheel help

Posted By Andrew Riehl
well, there's no one answer without some backround info--what is your intended use for it (film/ccd/etc?), what type of instrument will you be using it on, etc.? There's a huge number of options, but choosing depends specifically on your needs.

January 16, 2003 11:41 PM Forum: CCD Imaging and Processing/Solar System

Re: Blackeye...

Posted By Andrew Riehl
Thanks, but you'd have to grow 'out' to be like me, not up...I've tacked on some lbs. since I've been off work for back surgery smile It sucks; I haven't worked since the end of october, and I've had about 8 clear calm nights. Good news is, I go back to work in february, so then the weather will be beautiful all the time.

Funding Member

Sponsors


View all sponsors

Search