Firstlight for me with the R200SS and Pentax K10D

[h0ughy]

well I quickly set this up in the yard 2 hours ago and took some test shots. The Pentax was never meant for this type of work, it is my lunar and solar camera, but not being able to set things up as I like I have made do with the setup.

very much unguided, no alignment except for aiming for a tree to the south, and heaps of drift in very short exposures, but what the hell, I had a go.

:rofl: and the winning shots are
the moon
Sirius

[iceman]

Looks nice Dave, Sirius is very sharp.

[h0ughy]

thats with a rack and pinion focuser. just wait until its doctored with the robofocuser and moonlight setup when I am finished with this :whistle:

[strongmanmike]

This the new Vixen then? How did you get on with removing the corrector and collimation?

Mike

[h0ughy]

havent collimated it, and as for removing the coma corrector, look here (http://www.iceinspace.com.au/forum/showpost.php?p=205904&postcount=21);)

BTW Jim replied "Before I can give you the 'best" tool recommendation options, I need to know the Secondary minor-axis size in your Vixen?

Regards,

Jim Fly
CATSEYE Collimation"

so what am I measuring?:shrug:

[Dennis]

The secondary mirror is an ellipse, (oval like shape), and not a circular shape like your main mirror. When viewed at 45 degrees, this elliptical shape then appears to have the profile of a circle.

An ellipse has a long axis (major axis) and a short axis (minor axis) whereas a circle has just the one diameter.

I think it was Kepler who first proposed that the Planets orbit the Sun in elliptical orbits and not circular orbits?

So, you need to measure the short axis (minor axis).

Cheers

Dennis

[h0ughy]

Thanks Dennis, Jim probably thinks i am a dope - he might be right:whistle:

[Don Pensack]

I'm distressed that you removed the coma corrector. Now, coma will be quite visible everywhere in the field except for the very center, which will spoil any wide field shots this instrument is capable of.
If you've replaced the corrector, or plan to do so after collimation, please excuse the post.
By the way, the width of coma-free field in this scope is 0.0448", or 1.14mm.
Unless you plan to only shoot planets in the center of the field, a coma corrector of some sort is in order.

[h0ughy]

:scared: :scared: Dont panic Don, as I said I removed it to clean it up, it has some dust and crud on it, it was replaced for all images. I plan to later add a moonlight craford focuser and a baader MPCC so I can use filters and such.