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Achro (& Apo) Refractor - Cheap Chinese

Started by markvcostello3, 07/09/2004 03:54PM
Posted 07/09/2004 03:54PM Opening Post
">>it should be easy to become with AP a best seeling company for the new Chinese Apo Generation :-)>>" (Markus Ludes

"No, I don't think so. I would be the last to sell a Chinese made apo. It's not that I worry about quality or anything like that, but I have an obligation to my community to try to bring commerce and jobs here instead of exporting them to some other place. If Chinese apos become popular, I'll make something else. We have lots of ideas that no-one has tried yet.

Rolando"

Where are the American companies that make affordable achromat refractors with 80mm
As for the 93mm replacement cell or refractor, I have to tell you that - assuming that it comes in and is of good quality, I find it too be all too easy a decision to get it vs spending 2 grand on a TAK 90 or TV85 or waiting for AP to decide when if ever they will make new Stowaways or wait for who knows how many years to be able to buy a Traveler for about $3500.

Mark Costello
Matthews, NC, USA

"I hear you're mechanically inclined. Did you ever do anything with perpetual motion?"

"Yeah, I nearly had it a couple of times."
Posted 07/09/2004 04:14PM #1
That's fine, Mark. Buy what you want.

We are a small company and I am the only optician. I cannot compete with mass market optical firms that sell thousands and even millions of optics. The point is not whether I would make a cheap scope for you. The point is I will not buy Chinese made refractors for resale here in the US even if they are excellent quality (which I don't think will happen).

I have my own priorities in a more rarefied market that you probably will never enter or even be aware of. Yes, I could cut costs to the bone by using inexpensive die cast parts for the focuser and lens cell, but this would never work for the majority of our customers who like to hang $10,000 CCD cameras, heavy like hell, on the end of the focuser and expect less than .0001" of motion. In order to do that, I have to start with lots of metal and do some rather precise machining and fitting of parts. Heck, it takes a good hour or more to assemble just one focuser! The 4" focuser on the end of our 6" refractor weighs 9lb, that's more than a typical 4" Chinese telescope. Where do you want me to start chinzing on build quality?

You guys have no idea what it takes for some of this equipment. I have customers out there that worry about 2 arc seconds of periodic error in their mount tracking. Compare that to a typical Chinese made equatorial that produces random fluctuations of 50 arc sec or more! Totally useless for some imaging applications.

You think you can take just any stuff and do anything and everything there is to do in this hobby. Well, I got news for ya. There's more to this hobby than just looking at planets.

Rolando
Posted 07/09/2004 05:20PM #2
>>>As for the 93mm replacement cell or refractor, I have to tell you that - assuming that it comes in and is of good quality, I find it too be all too easy a decision to get it vs spending 2 grand on a TAK 90 or TV85 or waiting for AP to decide when if ever they will make new Stowaways or wait for who knows how many years to be able to buy a Traveler for about $3500.
-----------------------

Mark:

There are a couple of things to consider here:

1. You made a pretty big assumption in assuming the 93 mm will be of "good quality." After the last efforts, I just don't see how anyone can do anything more than just wait and hope with fingers crossed.

2. The comparison that will make or break the 93mm is not with the TV-85 or the TAK-90, these are mechanically on a different level.

The comparison of interest is with the Orion ED-80. With only 35% more light gathering power and near twice the price, the 93mm mm BO scope is really in some tight price competition. Orion was pretty smart in designing the ED, with the same 600mm focal length it is significantly easier to get acceptable color correction with an 80mm scope than with a 93mm scope.

I think it would be nice if BO can pull this one off, but it is a big order, from what I understand Fluorite glasses are difficult to work with, hard to figure, fragile, and yet to achive APO performance such as the ED-80, things need to be much more precise that with a simple achromat. Given the problems with the achromat, everyone, including Bill, ought to have serious concerns about whether the Chinese can pull this off.

jon

Jon Isaacs
Posted 07/13/2004 12:42AM | Edited 07/13/2004 12:44AM #3
All I can say to Mark, Tom and David is that because of you three Don Dickinson has become my hero!