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01-11-2014, 09:21 AM   #721
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QuoteOriginally posted by Ravvie Quote
I'd love to try out the astrotracer on a telescope but I thought it was impossible. On my scope the image is inverted and the eyepiece is at 90 degrees to the tube. Doesn't the astrotracer work by knowing which way the camera is pointing, then correcting for the earth's rotation relative to its orientation?
Hooking up your camera without the diagonal will make the image/orientation right.

01-11-2014, 09:28 AM   #722
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Wonder lf a 45degree correcting diagonal would work.
Hank
01-11-2014, 01:51 PM   #723
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QuoteOriginally posted by Ravvie Quote
I'd love to try out the astrotracer on a telescope but I thought it was impossible. On my scope the image is inverted and the eyepiece is at 90 degrees to the tube. Doesn't the astrotracer work by knowing which way the camera is pointing, then correcting for the earth's rotation relative to its orientation?
You are right. The Astrotracer will adjust sensor movements according to 1) focal length and 2) which way the camera is pointing. And if the latter is different from, which way the telescope is pointing, then the combo won't work at all.

Thus, one cannot use Astrotacer on Newtonians. In priciple, Astrotracer and small refractors or small CATS - withoit diagonal! - may work together. However, focal lenghts in excess of some 400-500mm may soon become a problem for the Astrotracer (allthough I have used mine occasionally up to 700mm). Expect the success rate to drop significantly if you go beyond 400mm.
01-11-2014, 02:20 PM   #724
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The inverted image is not a problem -the camera's own lenses also invert the image - it is the pentaprism that puts it the right way round.
The right angle orientation will be a problem though because ss you mention the radings from the gyros will not proprly correspond to the motion of the telescope with relayion to the subject.
It would need to be a Schmidt Cassegrain type or something lke it wit the eyepiece at the back for the SR to work.

01-12-2014, 01:37 AM   #725
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QuoteOriginally posted by Ravvie Quote
I'd love to try out the astrotracer on a telescope but I thought it was impossible. On my scope the image is inverted and the eyepiece is at 90 degrees to the tube. Doesn't the astrotracer work by knowing which way the camera is pointing, then correcting for the earth's rotation relative to its orientation?

Ah yes. I also have a reflector, and I think you're right: that would stuff it entirely.
01-28-2014, 12:17 AM - 2 Likes   #726
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Been a while since I shot any star stuff - last time I did serious astrophotos was back in October when I shot a bunch of film at a star party and did a little digital work at the same time. I haven't done anything with the film scans yet as the files are prohibitively large and I may rescan them at a lower resolution.

About two weeks ago a supernova was observed appearing in M82, an irregular galaxy that is very close to our Milky Way. This is an important event and like all supernovas of this kind, it gathers a lot of attention. I was no different and promptly set up my gear and got some pictures of the exploding star.




This picture is the sum of 40 subexposures, stacked to increase signal to noise and processed. The camera is a modified Pentax K10D that was converted to full spectrum and cooled with a peltier device.

Not sure what star is the exploding one? Here's the pointer:



To compare, here's an image taken about a year prior that does not display the exploding star:

01-28-2014, 02:56 AM   #727
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Wow!
That's the best photo I've seen of the SN/M82 so far.
Well done!
01-28-2014, 08:19 AM   #728
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@smigol: Beautiful galaxy shots in their own right - and a great capture of SN2014J!

02-14-2014, 03:36 AM   #729
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Sunspot Activity in February!

The current sunspot cycle should be near its maximum activity these days. I guess that's why I have had clouds and nothing but clouds for most of the time since November last year......

But this morning, as I was ready to go to work, I finally saw some blue sky. So, I grabbed my Thousand Oaks solar filter and my DA* 200mm and hoped for a few moments of opportunity. Well, fair skies only lasted for a couple of hours, but I managed to get 11 handheld shots reasonably suitable for stacking, and I found a pretty impressive string of sunspots along the Solar equator:


Pentax K-5 + DA*200mm + safe solar filter; 11 (handheld) images stacked in Registax 5.1; 1/400s - f/4.0 - ISO 200

Just 200mm and handheld - surely, this could have been better, but maybe an inspiration for others to pursue this opportunity?
02-15-2014, 04:44 AM   #730
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QuoteOriginally posted by Stone G. Quote
The current sunspot cycle should be near its maximum activity these days. I guess that's why I have had clouds and nothing but clouds for most of the time since November last year......

But this morning, as I was ready to go to work, I finally saw some blue sky. So, I grabbed my Thousand Oaks solar filter and my DA* 200mm and hoped for a few moments of opportunity. Well, fair skies only lasted for a couple of hours, but I managed to get 11 handheld shots reasonably suitable for stacking, and I found a pretty impressive string of sunspots along the Solar equator:


Pentax K-5 + DA*200mm + safe solar filter; 11 (handheld) images stacked in Registax 5.1; 1/400s - f/4.0 - ISO 200

Just 200mm and handheld - surely, this could have been better, but maybe an inspiration for others to pursue this opportunity?

Beautiful!
02-24-2014, 04:03 AM   #731
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Hello,
I've been browsing AP heavily since at least November and just now found this thread which I am now on page two of.
Ok, back to page two. See you guys when I'm caught up.
John
02-24-2014, 01:33 PM   #732
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Interesting discussion. Now all I need is a telescope...
02-27-2014, 01:49 PM - 3 Likes   #733
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Monkey Head Nebula Winter 2014

I've been working on a project for a little while, adding data over a few sessions under the sky. Four different nights went into the stack, giving just about 10 hours and 42 minutes of integration.




Still using my modified and cooled Pentax K10D with my trusty Stellarvue SV4 telescope. I'm still learning better ways to handle the parts and I'm on a long quest to eliminate off-axis flare. I've been flocking the scope and my next step is to design and cut an optimized petal-style hood to keep bright stars from robbing contrast.

It's now galaxy season and if I can get out between the few rain clouds, I'll work on the Virgo cluster.
02-27-2014, 03:59 PM   #734
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I admire your dedication and the result from it.
02-28-2014, 01:42 PM   #735
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It's really confronting seeing colours not regularly associated with darkness out there in print format as above.

Wonderful
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