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11-17-2011, 03:28 PM   #136
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I doubt that a motorized EQ. mount and scope combination that cost $160 or so, is good for anything but visual use. Just my opinion.

11-18-2011, 01:13 AM   #137
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QuoteOriginally posted by Ex Finn. Quote
I doubt that a motorized EQ. mount and scope combination that cost $160 or so, is good for anything but visual use. Just my opinion.
Agree. I sounds a bit too good to be true: Fast (f/4.3) scope AND Equatorial Mount AND motor drive...

What the add does not say, and what the would-be atrophotograper should be very keen on is the type and shape of mirror used in the scope. I suspect that this is a simple spherical mirror which isn't really satisfactory for anything and in particular not for astrophotography. The key-word here is "parabolic mirror".

As always, what you pay for is what you get. If on a budget (as I am) I would rather look for some used equipment of recognized brand-names.
11-18-2011, 01:41 PM   #138
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QuoteOriginally posted by krp Quote
I am looking to buy my first telescope and use it a lot for astrophotography. I would like to be able to view and photograph some galaxies, nebulas, comets, etc. Does this look like a good choice? Konus Konusmotor Electronic 500 Newton 114mm (4.5") Telescope 1781 FREE S&H 1781. Konus Telescopes.
I think once I have an EQ mount and tracking motor, all I need is a T mount to K mount adapter to start taking pictures. Am I missing anything?
Just don't expect miracles at once. You need to add lots of time and patience. Photographing nebulae etc. has a steep learning curve. Also, the scope you singled out, does not provide the stable plattform you need for long exposures and long focal lengthes. But if you place your camera with a fast, shorter fl lens, piggyback on the scope you can do a lot and learn a lot at the same time. For many objects you don't need focal lengthes beyond 200mm and even wide angle shots can be very nice and worth taking!

Generally for astrophotography the mount and the tripod are limiting factors, more so, than the telescope.

Ben
11-18-2011, 03:17 PM   #139
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Thanks for the replies. Lately I've been trying to photograph some nebula and improve them with stacking but I'm frustrated by the short exposure times I have to use. I was hoping a cheap EQ mount would be better than nothing since I can't spend much right now.

11-18-2011, 03:51 PM   #140
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You could always try upgrading a cheap EQ mount to improve its performance. Better than nothing Astronomy Boy: CG-5 Mount Improvements or you could always have a stab at a barn door drive Astronomy Boy: Barn Door Tracker
I have an el cheapo scope and mount (150mm Eden Optics Newtonian and EQ mount). When I get a round tuit, I will strip it down and see if I can improve its usefullness. I personally have nothing against some of the cheap scopes available. I remember my telescope making days from the 60's and know I could not build anything like them for the same price.
11-18-2011, 04:08 PM   #141
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Yup. I second on the barn-door. Dirt cheap, fun project even with limited skills. Even my crappy, made of pine, hand cranked one was good for couple minute exposures.
11-19-2011, 12:16 PM   #142
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First post here, I would suggest spending some time on Cloudy Nights astronomy forums. They have three photography sections and what some people do with 200 and 300mm lenses is amazing. You will find out that the most important part is the mount and a good one is not cheap. One problem on some of the Newtonians is the focuser does not have enough in travel to focus the camera. I do not know if this one will focus or not. I have not done any real astrophotography but have read about it for years and I have two telescopes. I am thinking about the gps astrotracer to get my feet wet but that is not an option for you with a KX. Good luck,
Scott
11-19-2011, 02:15 PM   #143
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QuoteOriginally posted by sadams Quote
One problem on some of the Newtonians is the focuser does not have enough in travel to focus the camera.Scott
This is a problem with my Eden Optics 150mm scope. I need to to do a major rebuild here to shift the prime focus out so it can be accessed. I will have to completely shift the spider assembly down the tube some 50-60mm, not an easy task as the spider and diagonal are a single unit. Drawtube and focusser could also benefit from a upgrade from 25.4mm to 50mm or so to reduce vignetting. Also the current diagonal minor axis is a bit on the small side. The rack and pinion focusser is rubbish; it is made from crap metal and is too coarse for fine focussing.
Also as the primary mirror is spherical, I am undecided whether to "convert" it to a schmidt type system or warp it to a paraboloid. I regard my current scope as basis for constructing some better. Even if I started from scratch, I still couldn't build it for the same price.

11-19-2011, 06:24 PM   #144
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Is there a way to use the time lapse feature for 2 minute exposures? I wanna doo star trails with less shots. It seems limited to 30 sec.
11-19-2011, 11:26 PM   #145
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QuoteOriginally posted by mrjamesabels Quote
Is there a way to use the time lapse feature for 2 minute exposures? I wanna doo star trails with less shots. It seems limited to 30 sec.
You might have to use a cable switch and time the exposure with a timer of some sort eg stopwatch. Alternatively you can always buy/build a dedicated programmable timer.
11-20-2011, 12:19 PM - 1 Like   #146
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Normal lenses & The very small and faint

QuoteOriginally posted by Ben_Edict Quote
Just don't expect miracles at once. -------

----- For many objects you don't need focal lengthes beyond 200mm and even wide angle shots can be very nice and worth taking!

Generally for astrophotography the mount and the tripod are limiting factors, more so, than the telescope.

Ben
You have a very valid point here.

Just as an example, here's the Ring Nebula, M57 in lyra shot with a K200D and a Tamron SP Adaptall-2 350mm f/5.6 (Model 06B). It is a stack in Registax of 12 images, each 30s at ISO 1600, post-processed in PhotoImpact. Images shown are resized 200% and 971(!!!)% crops, repectively.

M57 is tiny and fairly dim: Just about 1/30'th the diameter of the Moon and a surface brightness around 9. And, surely, "real" astrophoto gear can produce much, much better results. Yet, for me it is a thrill just to be able to capture these tiny and faint objects with an ordinary telephoto lens.

But without a decent EQ mount + tripod this couldn't be done --- or, so it may have been: Soon some of you lucky owners of the O-GPS1 may come up with something better
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11-20-2011, 03:14 PM   #147
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QuoteOriginally posted by pixelsaurus Quote
This is a problem with my Eden Optics 150mm scope. I need to to do a major rebuild here to shift the prime focus out so it can be accessed. I will have to completely shift the spider assembly down the tube some 50-60mm, not an easy task as the spider and diagonal are a single unit. Drawtube and focusser could also benefit from a upgrade from 25.4mm to 50mm or so to reduce vignetting. Also the current diagonal minor axis is a bit on the small side. The rack and pinion focusser is rubbish; it is made from crap metal and is too coarse for fine focussing.
Also as the primary mirror is spherical, I am undecided whether to "convert" it to a schmidt type system or warp it to a paraboloid. I regard my current scope as basis for constructing some better. Even if I started from scratch, I still couldn't build it for the same price.
It is easier to move the main mirror forward, than to move the spider and focuser to the back.

I don't know your Eden Optics scope, but converting a Newtonian to a Schmidt system is anything but easy, even if you stay with the classical layout and forego the Cassegrain focus. Making a Schmidt corrector is possible, but it needs a lot of experience in producing optical lenses. And to be honest, I guess it is cheaper and way faster to buy one of the lates generation of photographic Newtonians, like that one: 8" f/3.9 Newtonian Astrograph Reflector Telescope | Orion Telescopes

There has been a recent surge of these photographically optimized scopes, which are quite affordable and I guess, all in all it a much better solution, than to try to convert an old scope - unless of course, it is the hand-on experience you wish to make.

Ben
11-20-2011, 03:25 PM   #148
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QuoteOriginally posted by Stone G. Quote
You have a very valid point here.

Just as an example, here's the Ring Nebula, M57 in lyra shot with a K200D and a Tamron SP Adaptall-2 350mm f/5.6 (Model 06B). It is a stack in Registax of 12 images, each 30s at ISO 1600, post-processed in PhotoImpact. Images shown are resized 200% and 971(!!!)% crops, repectively.

M57 is tiny and fairly dim: Just about 1/30'th the diameter of the Moon and a surface brightness around 9. And, surely, "real" astrophoto gear can produce much, much better results. Yet, for me it is a thrill just to be able to capture these tiny and faint objects with an ordinary telephoto lens.

But without a decent EQ mount + tripod this couldn't be done --- or, so it may have been: Soon some of you lucky owners of the O-GPS1 may come up with something better
That's a decent result on the Ring Nebula with such a short focal length. Indeed, to really see more details, you would need to switch to a fairly big scope. One of of our astronomy club member's shots with our Meade 400RCX (400mm diameter): M57 (Ring Nebula) - You really have well done with your lens.

Ben
11-28-2011, 03:22 AM   #149
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Star trail

left camera shooting for 72 minutes, iso 1600, 30 secs subs. stacked with starstax on mac.
11-28-2011, 03:23 AM - 1 Like   #150
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Star trail

left camera shooting for 72 minutes, iso 1600, 30 secs subs. stacked with starstax on mac.
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