Posts Made By: Greg Nowell

http://www.gemini.edu/documentation/webdocs/preprints/gpre92.pdf


The Society for the Prevention of Cruelty to Light Beams notes that the Gemini South optical bench does not meet SPCLB requirements for the humane treatment of light beams.

regards Greg N

Jay Freeman on his personal web site indicates that proper care of a pair of binoculars does not include living in the car with extremes of heat in summer and cold in winter.

I'm wondering what the risks are here. I know several people who keep binoculars in their car "just in case." Is it something one only does for "cheap" binoculars?

I'm discounting the theft threat. My car is so full of junk that nothing in it looks attractive. Keep the binos in their case and under a piece of old newspaper....

thanks
Greg N

Viewing of Jupiter was unusually good last night. Sky was steady and supported magnifications over 600x. C14 seemed relatively stable. I know that I didn't get as much detail as I should, and am saving up my nickels for a real telescope, but I got some good views and I wanted to share them here. With the tracking and some nice color chalks, which I filled in better in the a.m., I was able to concentrate on the sketch.

Thanks for looking,

Greg N

Herb--

Everyone is going to want to know whether the Pentax-Borg 125 is a doublet, triplet, how well corrected it is for photography, and inevitably, the kind of glass it uses. I assume it's not a Petzval.

Could you pitch the product? I'm sure folks want to know!

thanks
Greg N

Tested these three binoculars today on a truck that was about 1/2 mile away across a river. Behind the truck, in deep shadow, was a tree trunk.

The results are consistent with you get what you pay for.

10x50 Bushnells (porros): hard to turn focus knob, limited focus range, a kind of "haze" over everything, very difficult to see details in the shadowy area behind the truck. Severe light scatter.

10x42 Vixen Alpinas roofs. A huge jump up from the Bushnells. Very clear. Good focus range, maybe better than the Vortex. But colors are just a tad not as bright and you can't quite eke out the same detail in the shadowy area.

10x42 Vortex Vipers roofs. Detail on the tree trunk and a small stick that is leaning against it is visible, not viewable in Bushnells and viewable with some difficulty in Vixens.

In sum the Vixens are a very good binocular if you had them you'd never think you were missing anything and the price to performance ratio is very good. At 2x the cost the Vortex Vipers give you extra value.

I am left wondering whether you get a tad more detail and color by spending $2k on some Leica or Swarovski 10x42s.

regards
Greg N

I did it once before but I'm failing now. I have shrunk my profile pic to 9kb and even to 5kb. I'm not getting an error message from astromart but I'm not getting the new picture up either. Am I missing something? Do I have to delete old pic first or something?

thanks Greg N

Is it my imagination or are these two eyepieces hugely more expensive than they were two years ago? They post at $319.00.

Also I was wondering if there is a "real price" (like the XWs) that is different from what you see on the web sites.

thanks
Greg N

I'm proud to say that I pitched the idea of a G8/G11 compatible tripod to Berlbach, helped in the development, and that this project helped bring them to the U.S. where they are now sold by Teton (that part was arranged by Berlbach and Mark R., I wasn't involved.)

You can take a quick look on the home page here:

http://groups.yahoo.com/group/extremeastronomy

If you go to the Losmandy group:

http://groups.yahoo.com/group/losmandy_users

You will find in the PHOTOS section a complete photo essay on the tripod in the Berlebach folder.

I have now used the PLANET/G11/FS128 configuration for, I guess, a year, although my first iteration with it was a prototype that differed somewhat from the current model (& I had to provide an adapter).

So what should I say: I think these beautiful pieces of equipment to use and the FS128/G11/Berlebach is a rock solid combination. YOu can get asphalt ball bottoms or use the spikes. The spike tips when pressed into the grass give an unbelievably stable platform. The damping time is next to nothing...not meaningfully measurable with any technique I have. It seems to do equally well on asphalt, too. It's very easy to work with this tripod in cold weather, and on the whole I find it easier to set up and use than the Losmandy default tripod.

I have used wood tripods made by Vixen for SP mounts and those "aren't bad" but compared to other kinds of equipment upgrades I have made, the Berlebach is really in the "wow" category because it has taken the whole concept to a different level. I'm afraid I have no comparative basis for Tak or AP tripods. However, if you buy a Berlebach I can't imagine that you would regret it. One of the things I like about it is I can get much better height for the refractor but I can also lower it if I want to. For example, if I'm going to be at an event with kids, or use a different kind of OTA. The Losmandy G11 tripod really needs an adapter to get to a good refractor height--leastaways something in the f/8 five inch category.

I love having a chance to show this thing off so I'm attaching a picture. I will say that to my knowledge this is the ONLY tripod that comes with a fully compatible G8/G11 adapter that has the mounting brackets for the Losmandy electronoics. To my knowledge the AP adapter (brought out in haste, I speculate, in response to the Berlebach) has no such provision; and most folks have to go with the rather unattractive Meade adapter from Losmandy to go to a wood tripod, and even then the adapter may need modification (concerning the center hole) for such mounts as AP, Tak, etc.

The Berlebach G8/G11 tripod adapter is surprising in that its machining and strength actually exceeds the OEM. When I got the finished version I was quite stunned at the quality. It seems the engineers said "lets not make this as good as, let's make it better."

regards
Greg N

Star trail of Losmandy G11 showing periodic error. Not bad, not great. (taken with ST7 on an FS128). 14 arc seconds peak to peak. Looks like you could probably guide this one out. Certainly no one is surprised to see a generic G11, vintage 2000, clock in at 14 arc seconds peak to peak. This is spot-on typical.

(part 1 of 2)

Greg N

From 1943