Les, ... I think that happens to all observers from time to time. I don't know how many times I got almost crazy because I couldn't find the place I was...
... diameter. ... around 40 ... add ... point ... suddenly ... eye, or ... Correct the 40% gain is applied to area. (a 40% gain in diameter would result in...
Hi Brian, Hmmm. I'm wondering if the "more complete" article I've written is being accessed for the fuller explanation. Actually, I've been waving that banner...
There are a couple of companies who make prism and grating eyepieces for the amateur market, but I can't find them after a couple of minutes of Google searches...
I will never be one to argue that binocular vision isn't superior to monocular vision. However, there is a big difference between a binoviewer in a single ...
I've had this problem just using DSS plates. Certain asterisms seem to recur all over the place. The Sagitta "Y" is very common, and "big dipper" asterisms...
I've never really understood this being enamored with the 3D effect in binoviewers. The effect is of course spurious since there is no true binocular...
Assuming a 30%D central obstruction in the 8" SCT, then LG is based on (64-5.76) = 58 sqin (nominal). After the remaining light gathering area is split in two...
... No, it's not that what you've written *in toto* is confusing. It's that very commonly, people don't read the thing in depth and come away with a partial...
... It is a little ridiculous to even imply that there is some "true" three-dimensional parallax effect for objects viewed in a binoviewer. However, It is the...
David Knisely
KA0CZC@...
Aug 1, 2006 5:24 pm
18582
I agree. It is so hard sometimes to get the clear point across, it doesn't pay to skimp on explanation. It often comes back to haunt. edz ...
Ed, Yeah, I did the math, too, but people had asserted that the contrast increase occurred in binoviewers as well as binoculars, but our little "experiment"...
Thanks Don, I see you have identified reasons other than binocular vision for the large differences you experienced. Assuming your eye's pupils are large...
The effects of binocular vision occur mainly as a result of the processing im raw image data by the visual cortex. For example, the brain interprets one photon...
Our star parties are canceled so often that it's not really a viable way to find out about equipment. I didn't see any prizm eyepieces at NEAF. I've tried...
... The usual term is 'direct-vision prism' or perhaps 'visual spectroscope'. Usually there is a chain of like five prisms cemented together in the...
Brian Skiff
bas@...
Aug 2, 2006 1:37 am
18588
... There is a company called Rainbow Optics which makes them. They have a website at http://www.starspectroscope.com/. I have never used any of their...
In the original thread on this star a few weeks ago I promised to have a look with my 70mm Pronto. A clear night has finally come along, and I've just had a...
Brian Skiff
bas@...
Aug 2, 2006 4:39 am
18590
In case you haven't heard/seen, the large-amplitude variable chi Cygni is near a bright maximum just now. If you're familiar with the main constellation...
Brian Skiff
bas@...
Aug 2, 2006 5:03 am
18591
... I believe Arnold Optics in Sherwood Park still makes a barlow with a prism above the lens. I have one. As Alister says it sure makes finding the faint near...
... But for those of us who have that semi-red-green-color-blind gene, like me, even Rigel and Betelgeuse only look sorta different, so down at mag 3 or 4,...
Brian Skiff
bas@...
Aug 3, 2006 3:59 am
18594
From tonight's astro-ph preprint server: http://arXiv.org/abs/astro-ph/0608080 Suarez et al A spectroscopic atlas of post-AGB stars and planetary nebulae ...
Brian Skiff
bas@...
Aug 4, 2006 4:51 am
18595
Some thoghts and experiences with outreach: Despite my lelndary personal charm and fine Irish wit, I was utterly unable to persuade anyone at the Shingletown...
Bill; I think that you did a great job for the novices looking through your scope. That is just enough information that they can hold on to some of it and not ...
Howdy all; Tonight was one of those nights that remind me why I built an observatory in my backyard. After months of cloudy nights in Arizona the storms...
Steve is right about the advantages of having a backyard observatory (or in my case just a place to plonk down the scope). The point that many amateurs seem to...
