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Posts Made By: Keith Fredrickson

April 17, 2018 05:15 PM Forum: CCD Imaging and Processing/Deep Sky

New Setup Test M101

Posted By Keith Fredrickson

I've been using the AP 160 for years visually and decided to try it for astrophotography. I wanted to try and capture a little larger image of some smaller DSO's and this seems to be a good combination of scope and camera for that.

30 minutes of luminance and red channels as a test, no calibration frames, just stacked and stretched.


AP 160
AP 900
QSI 660

Radius 0.363
Pixel scale 0.739

April 18, 2018 04:11 PM Forum: CCD Imaging and Processing/Deep Sky

SBIG STF8050C

Posted By Keith Fredrickson

Hello Mark,

I am not an expert and know just enough to be dangerous so take anything I say with a grain of salt.wink

You are imaging with a very difficult setup, large focal length, so i'm assume you are an experienced astrophotographer. I am familiar with the 8300 chip which is very close to the 8050 that you are using and the first thing that pops out is that with your setup the image scale is at 0.35"/pixel. That is very oversampled and you need excellent seeing conditions to pull it off. Your focal length is good for smaller DSO's but you won't get much of larger nebulas in the frame.

Secondly, with a color CCD camera there is the bayer matrix to contend with. Your DSLR that puts out raw files and takes care of this. When you processing the fit files of the color camera you have to tell the processing program what matrix it is, RGGB, GRGB, BRGG, or whatever it is for your camera, and I don't know what SBIG uses. With one color camera I had to take a daytime shot down the street and try all the different matrices until the colors where right, very difficult to do with your scope but if you have a small refactor it can be done. I'm strictly mono now. And yes, you need to take and stack a lot of frames if you want a pretty picture.

I probably told you things that you already knew but since you haven't had a response yet I thought I would throw out a little information.smile Good luck!

Keith

April 22, 2018 02:36 AM Forum: CCD Imaging and Processing/Deep Sky

Arp 34

Posted By Keith Fredrickson

A trio of interacting galaxies, NGC 4613, 4614, and 4615, that are about 220 million light years distant.

AP160
AP 900
QSI 660 - 5 hours LRGB

 

April 23, 2018 01:44 AM Forum: CCD Imaging and Processing/Deep Sky

Arp 34

Posted By Keith Fredrickson

Rod,

Thanks for taking a look and the comments. They range between mag 13 and 15, 4613 being the smallest and faintest. Arp 147 is pretty cool and is in the same magnitude range but twice as distant, maybe I'll give it a shot. I really need a 1/2 meter or larger scope (Hubble)smile for these...maybe someday.

May 17, 2018 12:03 AM Forum: How to make AstroMart BETTER!! My idea is.....

Forum Replies

Posted By Keith Fredrickson

When you hit reply to a forum post on the old site you saw the post you were replying to. Not on the new site and I'm old with fading memories.;^)

I also miss that you can't delete or re-list a classified after you marked it sold.

Keith

May 17, 2018 11:29 PM Forum: How to make AstroMart BETTER!! My idea is.....

Forum Replies

Posted By Keith Fredrickson

Originally Posted by Greg Shaffer


Use quoted reply instead..... I actually like that deleting sold ads is no longer valid for a number of reasons.
Fair enough, but sometimes I just want to comment and not quote.

I also can see reasons for not deleting an ad, just wish everyone would at least mark their ad sold...not done. When a buyer does ask to have it deleted...I guess they'll learn that it can't happen if it's already been marked sold. Maybe more sold ads won't be marked as such in the future.

May 30, 2018 11:28 PM Forum: AstroMart FAQ

New format needs work.

Posted By Keith Fredrickson

Anybody wonder why the forums have been so quite lately? There is no option to start a new topic.wink

May 31, 2018 03:01 AM Forum: AstroMart FAQ

New format needs work.

Posted By Keith Fredrickson

Originally Posted by Darian Rachal
Keith, if I click on Commentary and then Politics, I get a tab to the upper right that says "Start A New Thread".
Thanks Darian! I was so use to selecting the forum after hitting the start a new thread that I missed that.blush

May 31, 2018 03:08 AM Forum: CCD Imaging and Processing/Deep Sky

Portion of Hercules Cluster

Posted By Keith Fredrickson

Contains Arp 71, 172, 272, and almost 122 had I framed it correctly!sideways

AP 160
AP 900
QSI 660

8 hours



Larger Version

May 31, 2018 11:17 PM Forum: Digital SLR AstroPhotography

Rho Ophiuchus from Down Under

Posted By Keith Fredrickson

That's pretty incredible for 14 minutes. Nicely done!