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Tele Vue 85 Obsolete?

Started by rKGMzvFT5gL3s9, 10/19/2005 12:14AM
Posted 10/19/2005 12:14AM Opening Post
The author of the following link thinks so:

http://www.epinions.com/content_60670054020

He basically claims that the new Chinese APOs deliver the performance of the TV85 without the high cost.

Opinions?

The Tele Vue APO doublets have been available for 8 years, perhaps Al is going to introduce a new design?


Michael Aaron McNeely
TeleVue Forum Moderator
Astromart.com
Posted 10/19/2005 12:49AM | Edited 10/19/2005 12:57AM #1
My personal opinion:
Initially, I felt that the reviewer obviously has spent ample time behind the eyepiece of different telescopes and is clearly not a novice observer. I found the piece wonderfully written and the physical description of the TV85 to be right on. Furthermore, the comparison to the ED80's of Chinese origin echoes the sentiments of an in-depth review performed by cloudynights.com. BUT...

"Looking at the moon at 25X, where the entire moon is visible, the TV-85 showed a lot of color. Around the edge of the moon, in to about 1/8 of its diameter the color was a yellow green"

"Jupiter, on the other hand, is pretty close to white and false color is visible as a blue-violet halo"

These excerpts I find questionable. As the past owner of a TV85 and the present owner of a TV102, I never see any false color at 25x on the moon. Perhaps the reviewer had a decentered lens or was viewing the moon at the edge of the FOV? Or perhaps he was describing extra-focal color? A barely perceptible violet halo around Vega at 200x or more...maybe. The aforementioned excerpts have me rethinking my original assessment of the reviewer.

Interestingly though, the article makes a salient point worthy of discussion. Will the TV85 go the way of the Pronto/Ranger? I think that the Pronto/Ranger were discontinued because the market became flooded with cheaper alternatives that gave comparable views (ie Megrez, SV). With the advent of the 80ED's of Chinese origin, will the TV85 eventually be discontinued as well? From what I have read, the 80ED's are pretty much the optical equal to the TV85.

Just my thoughts...
Posted 10/19/2005 01:02AM #2
The author wrote this:
"There is now a long list of telescopes under this one's cost which will outperform it by any criterion you choose."

Gee, I'd like to see that "long list."

His/her experiences regarding this particular TV85's false color are like none I've read or heard of before. If I'm seeing false color around the moon at 25x as he/she described (albeit not described very well), then I'm thinking something aint right -- perhaps misalignment (objective, prism, eyepiece?), lateral color, atmospheric dispersion, or some other anamoly.

Cheers & best wishes.
-Dan
Posted 10/19/2005 01:11AM #3
I couldn't agree more with Evan on the color issue. The author did not state whether he had tried a different eyepiece and the color might simply be eyepiece lateral color ;-), a bothersome possibility that the author did not seem to consider. Another possibility is there was something wrong with the sample he used.

I own the TV-85 larger brother, the TV-102, and have looked through TV-85 on the Moon and there's simply no false color at all at low power and certainly not at 25x ;-).

As to whether the TV-85 is obsolete, I can't answer that. In my opinion, there'll be people who always look to a finely crafted instrument and of course with as fine an optics as can be for the design and will be happy to pay more for such an instrument.

Ron B[ee]
Posted 10/20/2005 07:02PM #4
Obsolete?

What did Al upgrade the CPU or something?

Bull hockey. A telescope does not become obsolete. Televue may be facing some still competition from other manufacturers, (with the hardest years yet to come) but the 85 is, and will remain (as long as it is manufacturerd) one of the best small apo's on the market. When it is finally retired, it will be a classic piece of american glass.

Like Ron, I also find the "reveiwer's" description of color is extremely questionable.

FWIW, I've had two (and a host of other telescopes besides) and loved each.

Tom T.