Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version 294 Likes Search this Thread
01-11-2014, 09:21 AM   #721
Site Supporter
Site Supporter
Ex Finn.'s Avatar

Join Date: Nov 2007
Location: Southern Maryland. Espoo. Kouvola.
Photos: Gallery | Albums
Posts: 7,975
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
Site Supporter
Site Supporter




Join Date: Dec 2011
Location: Loveland C0.
Photos: Gallery | Albums
Posts: 93
Wonder lf a 45degree correcting diagonal would work.
Hank
01-11-2014, 01:51 PM   #723
Pentaxian




Join Date: Jun 2010
Location: North Zealand, Denmark
Photos: Gallery | Albums
Posts: 1,516
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
Veteran Member




Join Date: May 2012
Posts: 733
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
Pentaxian
Tsuken's Avatar

Join Date: Oct 2013
Photos: Gallery
Posts: 2,420
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
Site Supporter
Site Supporter
smigol's Avatar

Join Date: Sep 2008
Location: Menlo Park, CA
Photos: Albums
Posts: 422
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
Veteran Member
blende8's Avatar

Join Date: Feb 2007
Location: Bremen, Germany
Photos: Albums
Posts: 1,521
Wow!
That's the best photo I've seen of the SN/M82 so far.
Well done!

01-28-2014, 08:19 AM   #728
Pentaxian




Join Date: Jun 2010
Location: North Zealand, Denmark
Photos: Gallery | Albums
Posts: 1,516
@smigol: Beautiful galaxy shots in their own right - and a great capture of SN2014J!
02-14-2014, 03:36 AM   #729
Pentaxian




Join Date: Jun 2010
Location: North Zealand, Denmark
Photos: Gallery | Albums
Posts: 1,516
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
Pentaxian
Tsuken's Avatar

Join Date: Oct 2013
Photos: Gallery
Posts: 2,420
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
Senior Member
Iksobarg's Avatar

Join Date: Feb 2012
Posts: 208
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
Junior Member




Join Date: May 2012
Posts: 42
Interesting discussion. Now all I need is a telescope...
02-27-2014, 01:49 PM - 3 Likes   #733
Site Supporter
Site Supporter
smigol's Avatar

Join Date: Sep 2008
Location: Menlo Park, CA
Photos: Albums
Posts: 422
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
Site Supporter
Site Supporter
Ex Finn.'s Avatar

Join Date: Nov 2007
Location: Southern Maryland. Espoo. Kouvola.
Photos: Gallery | Albums
Posts: 7,975
I admire your dedication and the result from it.
02-28-2014, 01:42 PM   #735
Veteran Member
tromboads's Avatar

Join Date: Apr 2012
Location: Melbs
Photos: Gallery
Posts: 1,240
It's really confronting seeing colours not regularly associated with darkness out there in print format as above.

Wonderful
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
astronomy, astrophotgraphy, astrophotograhy, bill, camera, dslr, dss, exposures, f/1.8, images, lens, light, lights, lp, moon, night, night sky, photography, pk tether, post, settings, sigma, skies, stars, starscape, street, thanks

Similar Threads
Thread Thread Starter Forum Replies Last Post
astrophotography with K-7 - issues =(. Please help? Nass Photographic Technique 40 02-10-2010 10:28 PM
Astrophotography with K10 J-Rod Photographic Technique 5 12-12-2009 06:08 PM
Astrophotography mithrandir Photographic Technique 1 11-26-2009 06:56 PM
K7 And Astrophotography Christopher M.W.T Pentax DSLR Discussion 49 11-25-2009 08:51 AM
Astrophotography elLuiggi Post Your Photos! 0 11-01-2007 05:43 PM



All times are GMT -7. The time now is 03:17 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top