O-GPS1 Astrotracer function is phenomenal!


Fquesnel

Link Posted 02/12/2013 - 03:07
Greetings

I recently got a K-30 (after my K-x died from dew condensing during night time shooting (oops!) and saw in the manual an astrotracer function(?!?). By coincidence I was thinking of buying one of these small equatorial mounts made for dslr cameras (namely iOptron Skytracker). I bought the o-gps1 unit required for the astrotracer and here is the result of my second attempt.




This was shot using an old pentax-A 135 mm 1:2.8 set at f/4.0. It is a stack of three 40 s shots using the astrotracer function. I am very pleased with this first result. I don't think I'll be buying an iotron any time soon. No star trails are visible on the image. Sure 40s is the maximum exposure I could get with the astrotracer instead of the 120 sec the unit suggested I could . But it's a lot better than the 2 or 3 sec I can get without tracking. And stacking images with deepsky stacker is really easy and make three 40 s shots look like one 2 min shot. As a bonus you don't have to take time setting up the equatorial mount. Just turn on the astrotracer wait for satellite lock, do the calibration and you're all set. Many thanks to the engineers at pentax who thought of this incredible device!
Francois Quesnel
When taking pictures always think of those who will see them... a hundred years from now!

My gallery
Last Edited by Fquesnel on 02/12/2013 - 03:08

johnriley

Link Posted 02/12/2013 - 08:54
The image is excellent, but does need correcting so the sky is black.
Best regards, John

nass

Link Posted 02/12/2013 - 12:02
I just bought one of these too and although I was less than overwhelmed by the manual on how to use it, I figured it out after a bit of googling around. For me it's just a tool to get non-trail milky way backgrounds to blend them into night shots and I think for this sort of simple purpose it looks ideal, and dead easy to take to location. One slight issue is that I'm about an hr south of London and shooting north is just a waste of time because of the light pollution, but hopefully I'll find some spots nearby to shoot in other directions. I actually bought it for this comet but I guess we'll see if anything is eventually visible
... just another middle-aged guy with a hobby. I have an extreme macro learning site at extreme-macro.co.uk - Pentax-centric, your feedback and comments would be appreciated!

LennyBloke

Link Posted 02/12/2013 - 12:26
I've been thinking about getting one of these, but what puts me off is all the talk of "stacking" and the post-processing needed on many forum posts. I appreciate that the more effort you can put in the better the results will be, but do any of you who have one of these manage reasonable shots without processing/stacking?
LennyBloke

Gwyn

Link Posted 02/12/2013 - 12:36
nass wrote:
I actually bought it for this comet but I guess we'll see if anything is eventually visible

You can see comet Lovejoy in the Plough before dawn this week. It's still too cloudy here for comet spotting, or astro photography.

Gravelrash

Link Posted 02/12/2013 - 13:01
I think that's awesome Francois. Any idea what we're looking at?

Steve
Steve

Sometimes I'm serious and sometimes not, but I consider sarcasm an artform. Which is it today?

Fquesnel

Link Posted 02/12/2013 - 14:03
Thanks everyone for your replies. About the color I'll have to work a bit more on that for sure.
The o-gps1 manual is pretty much useless for the k-30 which has two pages on the unit in its manual. Now that everything is set I just have to turn the settings to "B" and the astrotracer comes on automatically!
Stacking images with DeepSky Stacker is really easy and DSS is free so, why not! As a bonus stacked images are much less noisy than the original images. But with a wide angle lens I would think you'd be able to go for 2 or 3 min exposures which would reveal lots of details.
What we see here is a star cluster called The Pleiades or the Seven Sisters in the constellation Taurus. We can even hint on the blue nebula that surrounds the brightest stars.
Francois Quesnel
When taking pictures always think of those who will see them... a hundred years from now!

My gallery

LennyBloke

Link Posted 02/12/2013 - 14:49
Thanks for the extra info about processing Francois, it's encouraging to see such a great image from an early attempt
LennyBloke

dcweather

Link Posted 02/12/2013 - 15:12
I hope you post some more on here. All very interesting.

nass

Link Posted 02/12/2013 - 16:05
LennyBloke wrote:
I've been thinking about getting one of these, but what puts me off is all the talk of "stacking" and the post-processing needed on many forum posts. I appreciate that the more effort you can put in the better the results will be, but do any of you who have one of these manage reasonable shots without processing/stacking?

Sorry, I have not put any up yet but yes, even after one night I've managed an ok photo without any stacking. It's dead easy, as Francois says, switch it on, get signal ("calibrate"), put camera on B and shoot a shot on B. I managed a couple of ok shots (good enough that wife wants it as her desktop pic) although I'm after a higher standard myself so will probably go the whole hog with blending and stacking before I put something vaguely ok up. Oh and it's the wrong part of the year for a nice milky way shot and where I live is the wrong area. But to answer your question, very easy to use for a basic stars in the sky type shot.
... just another middle-aged guy with a hobby. I have an extreme macro learning site at extreme-macro.co.uk - Pentax-centric, your feedback and comments would be appreciated!
Last Edited by nass on 02/12/2013 - 16:06

richandfleur

Link Posted 02/12/2013 - 20:07
Ok, this is a whole other area of the K-30 I haven't found until now, so thanks for the heads up. Yes the manual is really weak on this!

Tutorials please! This sounds really cool.

Similar to the built in interval timers which are finding a lot of favour from video guys because you can do HDR shots from within camera on intervals automatically. The auto HDR setting provides quite natural looking results, so that's actually quite usable.

Although, like others, I've had the K-30 interval timer just stop for not real reason. No formal fix for this was ever issued unfortunately.

LennyBloke

Link Posted 02/12/2013 - 20:10
Cheers Johan - you've just increased my tempation another notch
LennyBloke

nass

Link Posted 02/12/2013 - 20:43
richandfleur wrote:
Ok, this is a whole other area of the K-30 I haven't found until now, so thanks for the heads up. Yes the manual is really weak on this!

Tutorials please! This sounds really cool.

Similar to the built in interval timers which are finding a lot of favour from video guys because you can do HDR shots from within camera on intervals automatically. The auto HDR setting provides quite natural looking results, so that's actually quite usable.

Although, like others, I've had the K-30 interval timer just stop for not real reason. No formal fix for this was ever issued unfortunately.

I can't say for certain as I havn't played enough with it yet, but I should think it's unlikely that in-camera HDR would work, because it has to be on bulb mode. But HDR blending on a PC after the fact should be ok, you might lose a little negative size because of star movement but beyond that I don't see any reason why not?
... just another middle-aged guy with a hobby. I have an extreme macro learning site at extreme-macro.co.uk - Pentax-centric, your feedback and comments would be appreciated!

richandfleur

Link Posted 02/12/2013 - 21:25
Whoops, sorry if that wasn't clear but I wasn't suggesting using HDR for astro work at all. That mention was in reference to using HDR on an interval timer, which was off topic for this thread, but is another completely separate cool feature of the K-30.

SteveEveritt

Link Posted 02/12/2013 - 21:50
So how does it "follow" the stars? You attach the GPS thingy and then what?
My Flickr link

"Life is what happens to you while you're busy making other plans" (John Lennon)
Add a Comment
You must be registered or logged-in to comment.