[Stone G.]

The original question was if the PK200D is any good for atrophotography and what lenses to use.

The answer to the first part is: YES indeed; the K200D has some very nice features for astrophotography:

- full control over noise reduction routines (even at "infinite" exposure times)
- mirror lock-up
- plug in for wireless radio control
- CCD with decent noice characteristics even at ISO 1600 with all noise reduction algorithms deactivated
- compatibility with a whole bunch of old (cheap/fair priced but excellent) primes

Regarding lenses, any good, reasonably fast prime (short or long) will do. Each lens has its own sky to show. I predominantly use the 55mm f/1.8 S-M-C Takumar, the Tamron Adaptall-2 200mm f/3.5 and the Tamron Adaptall-2 SP 350 mm f/5.6.

In regards of mounts and tracking, I believe every beginner should start doing experiences with fixed tripod wide-field astrophotography and the move up from there.

Personally, I use a second-hand Meade LX75 equatorial mount, which I got at a very fair price (say, less than for a good Manfrotto tripod + ballhead):



As for results, here is a simple stack of just 5 images of globular cluster M13 in Hercules exposed for 15 seconds at ISO 1600 from the midst of a city under severe light-pollution conditions:



Of course, such a picture, taken under such conditions, require a bit of additional post-processing, but that would be a thread in its own right.

Back to the beginning: The Pentax K200D is EXCELLENT for astrophotography!!!

Best Regards / Steone G.

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Last edited by Stone G.; 10-28-2010 at 02:54 AM. Reason: ---and then I forgot to mention that the picture shows M13!!!

[LeoTaylor]

here ya go ed

I've still got mine, but its a canon mount, so simply de-mounted ( 3 screws ) the canon mount from the tube section, (no longer a canon user ! ) and epoxied on a Pentax mount i stole from an old PK lens. Just saved me £24 , as the lens was foobarred anyway

Adaptors - Max DSLR Camera Adaptor

Hi,

The Max DSLR adapter looks like a nice product, combining a T-Ring and a 2 inch EP adapter into one piece.

To me its one advantage is a wider aperture.

The web site states the "advantage" of being shorter than a standard T-ring adapter but you had to extend your refractor. I find my focuser is almost always extended almost as far as it goes.

The Web site also states it avoids having the T-Ring unscrew during operation. I find the real problem is the EP holder thumb screw slips. I prefer anything that screws on over a tiny set screw on a smooth surface!

[Squier]

I use prime focus for my bird astrophotography, so anything do with EP's is a non issue for me.

Extension tubes are a requirement for prime focus, as whether using an original T mount or the better MAX dslr mount, there is not enough length in either to achieve proper focus. Somehere between 50mm and 80mm of ext tube is about the right amount

[JackBak]

I use prime focus for my bird astrophotography, so anything do with EP's is a non issue for me.

Must be the Corvus or Cygnus constellations.

[Squier]

Perhaps i shouldnt call it astrophotography, but photography using an astroscope. Trouble is, it takes longer to type

[JackBak]

Yeah, I knew what you meant, I just couldn't leave it alone . I've used my refractors in the same way but I don't have a nice Wimbley gimbal to follow things with.

[Squier]

I have used a gimbal, up until quite recently. A Manfrotto 393 and i loved it. Well built, smooth, takes huges lenses and costs a lot less than a Wimberley. Mine is pictured in the photos above

[melander]

Here is my first shot of the milkyway with my K-5, lens used was Samyang 8mm fisheye set at f/4. Iso 3200, 30 seconds exposure. In post I pushed the exposure 1 stop, amongst other things

[JackBak]

Nice shot melander, thanks. Any idea how long an exposure you could use before you get sky fog? Is this a particularly dark site?

[melander]

This is in the middle of nowhere, still got lightpolution from my city 40km away but I guess it would be better when it gets colder and less moisture in the air. Januari and february is usaly the best time for these shots.

Google Maps

[JackBak]

Thanks for the added info melander. I'm jealous of your dark skies, I looked at your Google maps link -- middle of nowhere for sure. You must have gone out to get your K5 'cause FedEx or UPS sure as hell didn't deliver it

[RipDaJacker]

Im new into astrophoto, 2 months sice i got my telescope... Now i have a big itch to replace my ol' trusty k10 with a k5, i cant imagine the stacked shots wiath a clean 3200, 6400 iso This is my best result yet, shot 2 days ago on a very clear type 2 sky. m42 Orion nebula, 200/1000mm telescope, EQ5 unguided mount. Iso bracketing and 60 frames stacked in deep sky stacker, 21 minues total exposure time.

[Gimbal]

Im new into astrophoto, 2 months sice i got my telescope... Now i have a big itch to replace my ol' trusty k10 with a k5, i cant imagine the stacked shots wiath a clean 3200, 6400 iso This is my best result yet, shot 2 days ago on a very clear type 2 sky. m42 Orion nebula, 200/1000mm telescope, EQ5 unguided mount. Iso bracketing and 60 frames stacked in deep sky stacker, 21 minues total exposure time.

Wow, but how did you do that? Unguided and 1000mm, please explain.

[RipDaJacker]

The mount is motor driven on ra and dec axis, if you do a good polar aligment you can get a nice tracking time up to 3, 4 minutes without stelar drift. Once turned on, the ra axis motor starts compensating for the earth rotation. Guided means that u also mount a special camera or modded web camera on the telescope hooked to a pc and using software like iris or starry night i belive, will adjust mount errors keeping in track stars that you select. That way you can have bigger exposure times like 10 minutes or more on a fainth object like a galaxy or nebula.

[Ex Finn.]

This is my best result yet,

That is a Stellar image. What scope did you use?.