Sky and Tel's apo review was depressing

The Williams Optics fluoro-whatever review was an eye opener. Why would
ANYONE spend over $3000 for an apo that displays noticeable aberrations?
Why can't Williams build a small 4" scope for that cost that does not
have the problems that one did? With the other 7-9 choices out there,
I saw nothing to recommend buying their scope. I've seen through 5
of the other brands and did not see the problems the tester saw in the Williams
scope.

Hi,

I use a William optics FLT-110 for the CCD imaging with my SBIG ST-10XME CCD
camera and its CFW-8A filter wheel.

This APO is really beautiful, the optics are excellent. I purchased the FLT-110
field flattener and I obtained Great images.

If you are interested you can see my website :

http://www.astrosurf.com/ccdaltazao

Best Regards,

Florent

--------------
CCD ALTAZ & AO web site : http://www.astrosurf.com/ccdaltazao

Pithiviers le Vieil/Jouy-En-Pithiverais-----------------FRANCE

My USA web site : http://members.aol.com/JEPobs/poiget.htm

Losmandy HGM TITAN / Gemini Goto mount
Meade 12" UHTC SCT OTA
William Optics FLT-110 & Megrez 80 Triplet APO OTAs
SBIG ST-10XME/CFW-8A/AO-7

"Richard" wrote in message
om...
The Williams Optics fluoro-whatever review was an eye opener. Why would
ANYONE spend over $3000 for an apo that displays noticeable aberrations?
Why can't Williams build a small 4" scope for that cost that does not
have the problems that one did? With the other 7-9 choices out there,
I saw nothing to recommend buying their scope. I've seen through 5
of the other brands and did not see the problems the tester saw in the
Williams
scope.


The review I read was a whole lot more favorable, including remarks such as:

"What we like: Excellent Optics"

"...exhibited no astigmatism"

"...only a very mild touch of S. A. from over correction"

"Vega showed no spurious color when in focus"

"...certainly beats the level of performance [color correction] provided by
two element ED models."

So whats not to like? Seems like a nice scope while you wait for your
Traveler.

Ed T.

So whats not to like? Seems like a nice scope while you wait for your
Traveler.

Ed T.



Two specific comments in the review come to mind:

"I judge the level of color correction in the Fluoro-Star to be a notch
below the finest models from Astro-Physics, TMB, and Tele Vue, whose star
images look almost pure white right through focus and under all seeing
conditions."

"However, as seen here, the 1st-magnitude star Deneb exhibits a prominent
"bipolar" flaring, an effect visible on only the brightest stars located
away from the center of the field".

Anders H.

--
correct address anhn at telia dot com

Anders Hansson wrote:
"However, as seen here, the 1st-magnitude star Deneb exhibits a prominent
"bipolar" flaring, an effect visible on only the brightest stars located
away from the center of the field".

Astigmatism plus coma, perhaps?

Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt

"Anders Hansson" wrote in message
Two specific comments in the review come to mind:

"I judge the level of color correction in the Fluoro-Star to be a notch
below the finest models from Astro-Physics, TMB, and Tele Vue, whose star
images look almost pure white right through focus and under all seeing
conditions."

"However, as seen here, the 1st-magnitude star Deneb exhibits a prominent
"bipolar" flaring, an effect visible on only the brightest stars located
away from the center of the field".



I had forgotten about the bipolar flaring. That is more troubling to me
than the out-of-focus color. It is priced between the ED doublets and the
premium triplets, so the color correction described seems reasonable.

Ed T.

Who makes the Fluorostar optics ?
D

You find that review depressing? Take a look at the review of Craig
Crossen's new book in the recent Sky & Telescope. It costs $70, but
based on the review, I expect to be able to pick it up next year at the
Barnes & Noble publisher's overstock bin for $3.98.
Bill Meyers


Richard wrote:

The Williams Optics fluoro-whatever review was an eye opener. Why would
ANYONE spend over $3000 for an apo that displays noticeable aberrations?
Why can't Williams build a small 4" scope for that cost that does not
have the problems that one did? With the other 7-9 choices out there,
I saw nothing to recommend buying their scope. I've seen through 5
of the other brands and did not see the problems the tester saw in the Williams
scope.

Bill Meyers wrote:
You find that review depressing? Take a look at the review of Craig
Crossen's new book in the recent Sky & Telescope. It costs $70, but
based on the review, I expect to be able to pick it up next year at the
Barnes & Noble publisher's overstock bin for $3.98.

What is the book about?

Brian Tung
The Astronomy Corner at http://astro.isi.edu/
Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/
The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/
My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.txt

"David" wrote in message
...
Who makes the Fluorostar optics ?
D


TEC is involved, not sure to what extent they control the process/specs.

Ed