Posts Made By: Steve Mathis

September 17, 2007 07:14 PM Forum: Celestron

focal reducer question

Posted By Steve Mathis

Hey, everyone...
I have a C11 with a sand-cast back. The original owner had a custom ring made for the 2" (I think) male threads on the back to increase the size of it to accommodate a large Crayford focuser. The ring is not removable, as far as I can tell. I would like to be able to use the Celestron f/6.3 focal reducer, but with the modification on this scope I can't thread a reducer onto the back. I am trying to figure out a way to go about this. I need to know the outside diameter of the reducer to even begin. Can anyone provide this information?

Thanks,

Steve

September 21, 2007 09:46 PM Forum: Celestron

2 Celestron Questions

Posted By Steve Mathis

Hey, everyone...
(1) Has anyone out there tried to get help through Celestron's Tech Dept E-mail? You have to submit a request form, then you get a "ticket". Two full days have passed since I submitted my questions, and the "ticket" still has only my question on it, with no response. How long should I expect to wait?

(2) (This is the question I submitted to Celestron) Does anyone know if there is an adapter available to convert the 3.29" diameter, 16 tpi threads on the back of my C11 to ~2" SCT threads? If so, where?

OK, that's more than two questions.

thanks for any input!

Steve

September 23, 2007 06:31 PM Forum: Equipment Talk

Making a Solar filter with Baader Film

Posted By Steve Mathis

Hey everyone,
I've ordered a sheet (7.9" x 11") of Baader Solar film and want to construct a filter for my C11. So, I'm wondering if I should make a 7" dia. concentric filter, or a 4" - 4.5" off-axis filter. The concentric construction has the relatively large central obstruction, whereas the 4" off-axis has a clear light path. Which one would give the sharpest, highest contrast image? Thanks for any insight here!

Steve

September 28, 2007 11:45 PM Forum: Celestron

C130mm Mak

Posted By Steve Mathis

So, I bought one of these without doing a lot of research. The name and the price pretty much convinced me to push the "BUY" button, and I did. Then I read the reviews. The stuff on CN forum. Have any of you folks purchased one of these? I performed one of the "prescribed" modifications on mine today, and it helped! I tore into a brand-new scope that I'd had less than 24 hours. cwy

but, grin

Steve

October 20, 2007 05:29 PM Forum: Digital SLR AstroPhotography

M 31

Posted By Steve Mathis

Hey, everyone. I got to spend a week at a dark site, and did a bunch of photography. I just got a C 130 Mak to use for manually guiding either my 6" f/4 homebuilt Newt, or my C11. It opens up a lot of targets! Here is M31 and company, a composite of 3 exposures of 10 minutes, 6 minutes and 3 minutes. The shorter exposures were used to help fill in the overexposed core on the 10 minute exposure. These were shot with a Nikon D70 through the 6" f/4 at ISO 1600. Thanks for looking, comments are welcome!

Steve

October 20, 2007 05:34 PM Forum: Digital SLR AstroPhotography

N.A. Nebula

Posted By Steve Mathis

Here's another photo from the recent trip. This is a single 12 minute exposure at ISO 1600 through the 6" f/4 Newt. Thanks for looking.

Steve

October 21, 2007 06:03 PM Forum: Digital SLR AstroPhotography

M 13

Posted By Steve Mathis

Another image from two weeks ago. This is a single two-minute exposure at ISO 1600 through my C11 @ f/6.3. Thanks for looking, comments welcome!

Steve

October 26, 2007 12:02 PM Forum: Digital SLR AstroPhotography

Another Holmes

Posted By Steve Mathis

Here is my image of Comet Holmes. This is a stack of 6, 5 sec @ ISO 400 through a C11 @ f/6.3 with a Nikon D70. Thanks for looking!

Steve

October 26, 2007 07:51 PM Forum: Digital SLR AstroPhotography

Hunter's Moon at Midnight

Posted By Steve Mathis

Hey, everyone. After shooting some photos of Comet Holmes, I couldn't resist pointing the C11 at that giant full moon overhead. Here is a 3 image composite ( a top, a middle, and a bottom smile ), 1/1000 sec @ ISO 200, C11 @ f/6.3 with my Nikon D70.

October 28, 2007 12:51 PM Forum: After Dark

Holmes Sunday Morning

Posted By Steve Mathis

Hey, everyone...I captured this image of Holmes this morning at about 6:15 AM local time. This is a stack of 16, 5 sec exposures at ISO 400 through my C11 @ f/5.6. Thanks for looking!