Posts Made By: Greg Nowell

It's something of a chore. The old RTV has to be removed. Then the whole affair must be remounted in the same orientation and remounted in a perpendicular manner.

You can get almost anyone to recoat but it's removal from the support structure and re-rtv-ing. We are pursuing this on Yahoo! C14 with a c8 that has been sent to a mirror coater, but it is taking a long time to get the results. That is to get the c8 back, and to get a cost estimate from the vendor as to how much they want to charge to do C14s. To keep track, join there.

regards
Greg N

You'll get better quality control with a Vixen. If you're going to get a rerfractor but don't want to get into the real high end then you might look at Vixen.

I personally would prefer a well quality controlled Newt to a cheap refractor. The Vixen five inch Newtonian is $200 and change and I'll bet they've paid more attention to consistency than some of hte other lines. At f/5 and five inches it would give just under three degrees with a Pan Optic 24 ($300) and so for $500 you get a wide field instrument where both components can be resold later. But I haven't been through a dozen of the five inch Newts so alas I'm just guessing that Vixen would do better there than Orion or Harding.

I think there are some Mak Cass's out there that would be a better choice for the money.

regards
Greg N

regards greg n

I prefer Purosol. Great for eyepieces, mirrors, what have you. I've used windex too.

Purosol is sold at a wide variety of places, including Astro-Physics. This is one:

http://tinyurl.com/2vu8ge

There is a complete "How to Clean Your Corrector Plate" tutorial on file at Yahoo! C14 group and also Yahoo! sct-user.
Includes pics and some appendices on other items related to performance.

It is the most streak-free results I've gotten of the various things I have tried on my optics. Incidentally Texas Nautical Repair uses kerosene!

regards
Greg N

If it droops into the fov it's called vignetting and it would show up as a dent in your star test. You should be OK as long as the rigidity holds and the diameter of the shield is larger than your primary optic.

The primary optical compromise is on the loss of stability. It will increase the sail area of the scope and depending on your mount, wind, and other factors, may lead to some shaking.

Refractors with dew shields as a general rule take a while to dew up; a four-inch is pretty easily de-dewed by holding it in front of the car's heater or using a hand held 12v heater. Or use an electric dew heater on the tube itself.

regards
Greg N

If you don't know what you're doing you should be getting a real good price or moving on to something that is better known. In the binoculars ads section you can find some knowledgeable people.

I bought some Canon 1970s binoculars they were nice but actually I like the more recent stuff better. New multicoated optics are better. If someone is offering you these for $20 then what the hey.

regards Greg N

The rating is for those occasions when money changes hands, and that's the way it should be.

Look at it this way. When you run a newspaper ad you get all kinds of crazy calls that waste your time. This is no different.

Your only alternative is to sell to people you know.

No wait, there's another alternative. You can place stuff at auction. Anyone who does not pay gets booted from the 'mart.
You will still need to answer questions.

regards
Greg N

Well--answering part of my own questions, seems like it's a petzval according to this UK site (didn't see the petzval part on ATWB):

Features:
* Newly redesigned, advanced lens elements allow dramatically improved optical performance
* Objective lens cell is produced by Borg's new partner - Pentax, Japan, which produces the
highest grade optics in the industry
* ED F/4 Reducer (7704) combines with the 125SD to create a fast optical system - F/3.9
astrograph (6 elements & 2 SD/ED elements in an advanced Petzval optical design), which
covers 35mm full format sensors
* 0.85x Field Flattener (7887) creates a 5 element Petzval system at F/5.1, which achieves a
virtually flat illumination across 35mm full format sensors
* 1.4x Teleconverter (7214) configures the system as a 1050mm F/8.4 imaging system
suitable for lunar, solar and planetary targets
* Borg's modular design allows for easy airline packing, making possible overseas
astronomical expeditions without compromising optical quality
* Compatible with wide range of Borg adapters and accessories
* Lightest OTA weight in its class allows use of a small mount
* Focuser options - Borg Helical Focuser M (7835), Borg Helical Focuser MDX (7837), Any
Borg M57 focuser via adapters, Feather Touch Focuser FTF-8C and FTF-M57 (via FTF-BORG
adapter)

I saw a pair of these just this a.m. near the Mohawk river in upstate N.Y. The yellow tail line. They were more tan than yours and I wonder if they are immatures or a local variant. Yours is a bit yellower--like the ones in the books.

thanks
Greg N

In the old days I would $20 to fill the Corolla and watch the SUV people pay $40 or more (and often have to fill up more often). They were paying $20 more than me per-fill-up.

Now they're paying $40 more than me per fill-up. It's a simple ratio thing of course but $40 more per fill up is a lot bigger of a budget ding than $20. I'm out of pocket $20 bucks more and they they're out $40 bucks more. Judging from income demographic data I see, I could afford to run an SUV more than most people who actually *are* running SUVs, so I figure there must be some real pain out there.

Meantime I've been thinking of buying an SUV and keeping my scope in it. But I decided that in the end it is more economical just to keep loading the equipment into the Corolla.

Had a guy stay and watch the other night while I loaded C14, AP900, ATS pier, accessory box, Star Blast, 102mm refractor, and eyepiece box into the Corolla long with my 8 year old son & his sleeping bag. Car won't take a 15" Dob rocker but you can get a fair amount of optics in if you choose the scope partly as a function of the vehicle rather than vice versa.

Anyhow this guy just hung around because he wanted to see how I could do such a feat of loading. As the owner of a C11 his gear was pretty compact but he still had a pretty big vehicle for it.

Today I was driving in to work and noticed a long line of SUVs in the middle lane driving at the speed limit. I don't know if it was a club or a chance encounter. Seems like for some reason they're trying to save on fuel.

Calculation of carbon impact is always on best alternative. A hummer used only lightly is still going to last 150,000 miles or more, and will always end up using more fuel/making more carbon than a more efficient alternative.

*Once the vehicle is made* it will be used for its useful lifespan. The only question is how the hit is taken. The sellers of these SUVs are taking a hit to their capital accounts in order to decrease their operating costs. The poor people buying the inefficient cars are trading discounted capital cost for increased operating cost. They actually are getting the better end of the deal because the future price of gasoline is a speculative bet.

Tremendous amonts of carbon go into the manufacture of vehicles. The ones built to last 2x as long for 1.2x the price are much more carbon efficient than the ones that die and a new one made. Factor in fuel efficiency and you have a thorny calculation.

But most people are just running from the price of gasoline, to heck with carbon footprint. I'd like to say "it doesn't affect me" but I know it does. My life depends on the general economy and people are hurting so that's going to come at me one way or the other. "No man is an island."

On the other hand, as the owner of a small vehicle for two decades because it doesn't make sense to use four tons of metal to go to work, I will be very grateful if fuel prices force people to pursue "safety" by buying smart rather than by buying big. For one thing, I'll feel safer. It already feels safer just having SUV drivers slowing down and being a tad less aggressive on the roar-up-behind-and-tailgate at 85 mph thing.

regards
Greg N

Worm upgrade on Losmandy G11. Set up the same as before (FS128, ST7, stars near celestial equator, mount deliberately throne out of polar alignment).

What do you estimate the PE to be? (the numbers are still being crunched so your guess is as good as mine).

Details on Losmandy Yahoo!

(part 2 of 2)

regards
Greg N