Three Galaxies and Keyhole

[alexch]

Hi All,

The Monday night forecast looked good so I packed my camera gear and 22" Dob and went to my favourite spot in Flinders. After setting up the panning time-lapse Greg and I had a rather long observing session. The seeing was average so we stayed at low powers and the highlight of the night were a few galaxies near LMC (in Dorado and Volans).

The time lapse is here (http://users.on.net/%7Eche/time-lapses/2011/Three%20Galalaxies%20%28Flinders%29 .mp4) (23MB MP4)
Less bandwidth consuming but lower quality video is here on Vimeo (http://vimeo.com/19469725)

At the end of observing Greg (from MPAS) lent me his Pentax K-x, I put it into the focuser of my Dobsonian and took my first ever DSO image through the telescope. It was windy and my Dob astro-photography expectations were quite low, but I rather liked the result on the camera screen so kept going. Because of the wind I could only use two frames of the Keyhole nebula and the result is attached below.

Finally I feel my post in the Deep Space section is justified :)

Tech data below.

Timelapse
Nikon D700, 14-24mm lens, ISO 3200, 754 frames x 30sec
Orion Teletrack motorised mount for panning effect

Keyhole Nebula
Telescope: 22" f/3.6 reflector on Alt-Az Dobsonian mount with imaging Paracorr
Camera: Pentax K-x
Image: 2 x 6 second frames at ISO6400
Processing: DSS for stacking and Photoshop CS5 for levels, noise reduction and sharpening. The final frame is not cropped, just resized.

Cheers,
Alex

[Bassnut]

Very excellent timelapse, very ordinary keyhole.

[alexch]

Agree 100% with the above.

However taking the first time ever deep space image was quite an exciting bonus to the observing session. I did not expect to get anything remotely usable with 6-second short exposures on Alt-Az Dob mount. I was also surprised that the whole field of APS-C size sensor in Pentax K-x looks okay with Paracorr and will investigate de-rotating devices to allow longer exposure times.

Cheers,
Alex

[gregbradley]

That's a great time lapse. Welcome to the deep sky section!

Greg.

[Bassnut]

Ive changed my mind, thats a very excellent keyhole for what.....2 off 6 sec exposures??, insane.

[irwjager]

That time lapse is awesome!

Yes, the Keyhole Neb is average compared to the gems we're being treated do on a regular basis here on IIS, but when you consider that's just 2x6s frames on a bog standard DSLR it becomes quite impressive. Who says you can't do DSOs with a dob! ;)

[alexch]

I was quite perplexed myself but I guess 22" of aperture helps shorten the exposure time.

Fred, I noticed a Pyxis de-rotator in your signature. Could you share how well does it work with LX200 and MOAG? I was thinking about either pyxis or this unit:
Orion SteadyStar Adaptive Optics Guider w/Rotator (http://www.telescope.com/control/product/%7Ecategory_id=autoguide_solutions/%7Epcategory=astro-imaging/%7Eproduct_id=53077)

Cheers,
Alex

[alexch]

Greg, Ivo - thanks heaps!

[Bassnut]

The pyxis works very well (both OTAs) and is very solid (3in version), it is however VERY noisy and VERY slow, but there aint many choices, I dont know the orion at all.