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Posts Made By: James Robinson

February 22, 2006 05:05 AM Forum: Telescope Making

Reflect-O-Putty

Posted By James Robinson
I think I read something once about spinning parabloic mirrors on turntables. I think the material was epoxy, not sure what it was coated with for reflectivity. I can't remember the purpose, but I don't think it was visual astronomy.


February 26, 2006 09:03 PM Forum: Equipment Talk

6.3 focal reducer problems with a C8

Posted By James Robinson
Hi Dwight,

You didn't specify an eyepiece, you might try some different types. I have a Celestron 6.3 focal reducer on my C8. Everything comes to focus except my 2" BW Optic 30mm eyepiece with a 2" Diagonal.

Jim

March 1, 2006 01:43 PM Forum: Equipment Talk

EQ head for LOMO 150 Mak on Stellarvue tripod

Posted By James Robinson
I would think a GP or clone (CG5) would do nicely for visual.

March 2, 2006 04:56 AM Forum: Birding Optics and Photos

Scope for Canon 20D

Posted By James Robinson
Well, you've had a lot of good advice already. If you can deal with the weight the 80ED should be great. I had a TV85 for a while and optically it was superb. As a birding scope I got tired of lugging it around. I now have a TV Ranger, only a few pounds. Visually it is a great birding scope. However there is a lot of annoying color in photographs. Its a strange thing, I've looked hard and never see it through the eyepiece, its nearly always there in photographs. So I suggest an APO if you go the refractor route.

I also have a Questar field model, suggested by someone else. It is superb in every way, but, the focal length is very long. To do wildlife photographs you need a bright sunny day and high iso setting.

Another non-refractor option is one of the fast Maks that were sold a few years ago under Orion and Pro Optic brands. A lot of people don't like maks for photos, weird backgrounds, but I've had good luck with a Pro Optic 90mm f 5.6. Very light, no false color.

And a final option, heavier than the others, a C5 with focal reducer.

So, having tried lots of things I suggest you avoid fast achromats, the color in daytime shots will annoy you. That leaves APOs and Maks/Cats of various stripes.

Jim

March 8, 2006 02:46 AM Forum: Birding Optics and Photos

Connecting a camera to a TV 85

Posted By James Robinson
Hi Mark, are you sure you want to digiscope with an eyepiece? You could shoot prime focus with a simple camera and T adapter. If you want more power I think you could put a barlow in front to do negative projection, but I haven't used that technique and don't know how well it works.

The T-adapter fits on the canon mount and threads into the camera adapter, which then slips in like an eyepiece.

Jim

March 22, 2006 01:32 AM Forum: Birding Optics and Photos

Belted KingFisher

Posted By James Robinson
Nice, I those are cool birds. What did you capture it with?

March 25, 2006 01:18 AM Forum: Birding Optics and Photos

Gadwalls in blue

Posted By James Robinson
After some mucking about in photoshop, color is still off.

Shot with my TV60, the ducks were too far away to get a high res shot but I love this scope, really sharp and detailed through the eyepiece.

April 3, 2006 01:41 AM Forum: Birding Optics and Photos

Geese and bufflehead

Posted By James Robinson
And the male

April 22, 2006 02:10 AM Forum: Birding Optics and Photos

Snowy Egret

Posted By James Robinson
Another view

April 27, 2006 07:50 PM Forum: Birding Optics and Photos

15X for birding?

Posted By James Robinson
How about both grin I would be concerned about the weight with the 15x. I don't think the magnification difference is enough to matter unless the apparent field of views differ. I'm not familar with the 12x, I have the 10x30 IS and they are very nice, good FOV and lightweight.

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