Orthoscopic eyepiece question

IMHO, however, the orthos are *not* suited for anything other than
planetary and double star observation - the field is just too small.

I used nothing but orthos for many years for all observing. I never found
anything substandard about the apparent FOV. Since then I've acquired a variety
of Plössls, Naglers, Panoptics, etc., and I probably wouldn't go back to orthos
for deep-sky. But I could see somebody being satisfied with them, even these
days. When the seeing is especially good, though, and the sky invites me to
crank up the power for planets, I reach for my Clavé Plössls, one of which I
bought from a gentleman who's already posted several times in this thread.
--
Curtis Croulet
Temecula, California
33° 27' 59"N, 117° 05' 53"W

wrote in message
...
On Fri, 25 Jul 2003 03:50:07 GMT, "Alan French"

Well, comparing Tak orthos to some Meade 4000s and TeleVues I found
the Taks to have more contrast and also to have almost no colour cast,
which I couldn't say for the Plossls.
-Rich

Rich,

Sorry, that is only your subjective opinion. While it may be enough to
convince you which eyepiece to buy, it does not provide much useful
information to others. Objective testing requires actual data. Resolution
as a function of contrast would be a start, but no one reviewing eyepieces
seems to want to bother with such things.

Such informal, subjective comparisons can be somewhat helpful, but more
details would be nice. What objects were observed? What telescopes were
they tested on? Exactly what were the differences? What did one eyepiece
show that was not visible in the other?

Clear skies, Alan

On Sat, 26 Jul 2003 15:52:39 GMT, "Alan French"
wrote:

wrote in message
.. .
On Fri, 25 Jul 2003 03:50:07 GMT, "Alan French"

Well, comparing Tak orthos to some Meade 4000s and TeleVues I found
the Taks to have more contrast and also to have almost no colour cast,
which I couldn't say for the Plossls.
-Rich

Rich,

Sorry, that is only your subjective opinion. While it may be enough to
convince you which eyepiece to buy, it does not provide much useful
information to others. Objective testing requires actual data. Resolution
as a function of contrast would be a start, but no one reviewing eyepieces
seems to want to bother with such things.

Such informal, subjective comparisons can be somewhat helpful, but more
details would be nice. What objects were observed? What telescopes were
they tested on? Exactly what were the differences? What did one eyepiece
show that was not visible in the other?

Clear skies, Alan

I said the same thing a couple years ago. Why not testing of
eyepieces the way main optics are tested?
-Rich

"Chris1011" wrote in message
...
Sorry, that is only your subjective opinion. While it may be enough to
convince you which eyepiece to buy, it does not provide much useful
information to others. Objective testing requires actual data.
Resolution
as a function of contrast would be a start, but no one reviewing eyepieces
seems to want to bother with such things.

This lack of objectivity is the usual way things are tested here. Most
reviews
in the two astronomy magazines lack hard data because they simply publish
what
some amateur finds in his visual examination of a product (the recent
eyepiece
review and Solar Filter review in Astronomy are examples). Rarely is a
test
instrument used to determine any parameter. This is in total contrast to
the
Japanese magazines where the staff has access to a complete optics lab.
There,
the products are thoroughly tested using standard accepted methods and the
results are published.

Roland Christen

Yeah, I find it pretty frustrating as I'm still relatively new to this.
There's nothing worse than going out to observe, seeing optical anomalies,
and not knowing whether its in the equipment, or some effect of the eye. It
can really distract you from the purpose for which you went out. If the
optics are without question, one can try to resolve the problem with less
testing on their own (which isn't always cheap).

I see a lot of posts here trying to calm people down, and lower their
expectations. Like the great WideScan debate. What was wrong? The eyepiece,
collimation, coma, angle of the light cone, exit pupil,
curvature/accomodation, or some incalculable and subjective mixture of all
of them. I say the edge is crap at F5. Not a very objective description, but
then I'm not equipped to measure, or experienced enough by eye to accurately
define the spot diagram. So I'm relegated to using the term "crap", which
may sound subjective, even though the anomaly is _very_ real, and not stated
without comparison to a second subjective experience using a second ocular
of known and well reputed quality.

If I knew for a fact, by an act of optical testing, that the WideScan
provides a diffraction limited view across the entire field in an F5 scope,
I would have looked elsewhere for the problem. But, beyond my own
experiences, I don't know anything other than what a handful of subjective
opinions and experiences tell me. And these are all too often heavily
influenced by the fact that the opinning are justifying ownership. Not to
say that justifying low cost alternatives isn't important for those who
can't afford better. But such opinions shouldn't be voiced simply to
discount the experience of those who consider it to be crap, especially with
public musings over the truly subjective and unknowable issues such as
incorrect usage, and/or possible problems with the reviewers eye, and
particularly when those issues are resolved by virtue of having been done
against a control sample of known quality. (Not that I'm trying to rehash
that here, but it is a classic example of the fact that reviews and
counter-opinions can get bogged down in the muck of personal opinion).

Even Cloudy Nights reviews and Ed Ting reviews require trust and a sense of
personal association with the reviewer (if he likes it, then so should I).
This equates to little more than positive peer reinforcement, in that at
least some people have an idea of what they want from looking at brochures
and listening to others opinions, mixed with personal tastes of what looks
cool. For some, a review only serves to confirm an opnion already held.

Using others equipment at star parties, or wherever, goes a long way to
gaining experience with differences in the eyepiece, which is extremely
helpful, but then without extensive participation over months and months,
one is left lacking other important knowledge and experience, like how
difficult is the setup and maintenance of the optical system...
collimation... etc. Lacking these skills, one is even more dependent on
control samples of known quality against which to measure the performance of
the rest of the system (like using a 35mm Panoptic and an 9mm Nagler to
evaluate the field of an F5 system as seen through a 30mm WideScan g).

Stephen Paul

Chris1011 wrote:

This lack of objectivity is the usual way things are tested here. Most reviews
in the two astronomy magazines lack hard data because they simply publish what
some amateur finds in his visual examination of a product (the recent eyepiece
review and Solar Filter review in Astronomy are examples). Rarely is a test
instrument used to determine any parameter. This is in total contrast to the
Japanese magazines where the staff has access to a complete optics lab. There,
the products are thoroughly tested using standard accepted methods and the
results are published.

The deplorable lack of objectivity is common to American magazines
specializing in consumer technology, where measurement is both possible
and desirable. They have abdicated to a cheer-leader position for their
advertisers. It's disgraceful. And readily apparent in my other two
passions as well - skiing and audio.

The saddest thing is that it wasn't always such; years ago the consumer
could find published measurements of equipment to aid in his purchases.
I don't know whether the reader or the magazines were dumbed down
first. I suspect it's a mutual failure.

Are the Japanese magazines available in English translation?

In article , Brian Tung wrote:

So, to bring this back on topic, if a U.S. magazine were to print numbers,
I imagine there would be many readers who already own the product in
question, and would insist that the product performs nigh-perfectly, and
damn the numbers. And there would not be enough to oppose them, I think.
It is "safer" to just print one reviewer's opinion--and perhaps less
actionable.

And, in addition, if a US magazine was to print numbers, and there
had been an error so that the numbers were wrong, the magazine might
be .s.u.e.d. for huge amounts of money by the manufacturer of the
reviewed product for hurting their business.

Just think about those US eye doctors who, to ensure they won't be sued
by their patients, strongly advices against looking at the Sun with your
unprotected eyes EVEN WHEN THE SUN IS TOTALLY ECLIPSED.

--
----------------------------------------------------------------
Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN
e-mail: pausch at stockholm dot bostream dot se
WWW: http://www.stjarnhimlen.se/
http://home.tiscali.se/pausch/

John Steinberg wrote:

(snip)

Not quite. Freedom of the press provides fairly wide legal latitude
when publishing, and that includes the freedom to make mistakes.

I'm hard pressed to think of any monthly publication that I read that
hasn't made numerical errors on some occasion -- some make mistakes as
regularly as clouds rolling in on a new moon night.

I read a healthy dose of publications where numbers play a vital role,
and almost invariably there's a published letter to the editor showing
them the error of their ways. Failing that, if spotted, an editor's
note and apology are SOP.

(snip)

Keeping in mind that my memory is aging, I _believe_ that Bose successfully
sued Consumer Reports for a less-than-glowing review of some of their
speakers. I believe they had to print some kind of retraction in addition
to a cash settlement.

Bose is not only a master at marketing mediocre (at best) stuff as
wonderful, but bulldog-nasty too. (Hmmm. I wonder who would be the optics
equivalent.)

Zane

John Steinberg wrote:

(snip)


However, I've provided a link to the case you cite and you'll see the
outcome was not _quite_ as you recall. At least the way I read it, the
Bose legal team was attempting to prove malice on the basis of the
thickness of a frog hair.

Aging memory is a suitable defense so you'll ..oh, nuts, I forgot what
I was going to write.

Anyway, here's the cite:

http://caselaw.lp.findlaw.com/script...&vol=466&invol
=485

Thanks for the link -- now I'm more confused than I was! :-)

In my own defense, this took place over a period of some years -- 14 if I
read the dates right. Different courts made different rulings and Bose
persisted in taking them all the way to the Supreme Court. (I didn't
remember that they were picking over "room" vs "wall", if I ever knew
that.) I don't think I understand the implications of the Supreme Court's
ruling in the site cited.

Bose is not only a master at marketing mediocre (at best) stuff as
wonderful, but bulldog-nasty too. (Hmmm. I wonder who would be the
optics equivalent.)


We could be treading on dangerous ground here, but I note for the
record that one of my cars has a Bose audio system and it only sucks in
comparison to the Harmon/Kardon system in another.

I was thinking of home stereo and home theater equipment. As to cars, it's
pretty much impossible to get decent sound inside one, as you may know.

An anecdote of my own -- I know a guy who designs and manufactures some of
the most critically complimented speaker equipment for the auto
aftermarket, besides very nice other speakers, for the cost. I once asked
him what he listened to in his car and he said Sennheiser headphones.

Zane

Zane wrote:
John Steinberg wrote:
CLIP

http://caselaw.lp.findlaw.com/script...&vol=466&invol
=485


Thanks for the link -- now I'm more confused than I was! :-)

In my own defense, this took place over a period of some years -- 14 if I
read the dates right. Different courts made different rulings and Bose
persisted in taking them all the way to the Supreme Court. (I didn't
remember that they were picking over "room" vs "wall", if I ever knew
that.) I don't think I understand the implications of the Supreme Court's
ruling in the site cited.


Bose is not only a master at marketing mediocre (at best) stuff as
wonderful, but bulldog-nasty too. (Hmmm. I wonder who would be the
optics equivalent.)

In fairness, I think the whole thing is a matter of out-of-control
lawyers. It sounds like Dr. Bose got lawyers involved when he set up the
company; and once those house dog-lawyers latched onto a case they
couldn't let the meatless bone go, even to bury it.


We could be treading on dangerous ground here, but I note for the
record that one of my cars has a Bose audio system and it only sucks in
comparison to the Harmon/Kardon system in another.


I was thinking of home stereo and home theater equipment. As to cars, it's
pretty much impossible to get decent sound inside one, as you may know.

An anecdote of my own -- I know a guy who designs and manufactures some of
the most critically complimented speaker equipment for the auto
aftermarket, besides very nice other speakers, for the cost. I once asked
him what he listened to in his car and he said Sennheiser headphones.

It's illegal to listen to headphones in a car around here ...

lal_truckee wrote:

(snip)

In fairness, I think the whole thing is a matter of out-of-control
lawyers. It sounds like Dr. Bose got lawyers involved when he set up the
company; and once those house dog-lawyers latched onto a case they
couldn't let the meatless bone go, even to bury it.

Again with the memory disclaimer, I heard they also went after some other
companies for patent infringement, like Meade. At least one patent
involved was for an obvious design approach for a "subwoofer" that had been
used well before Bose adopted it. So I think you're right.

(snip)

It's illegal to listen to headphones in a car around here ...

That probably makes sense, although my open Sennheisers let you hear
ambient sound pretty well -- not much different from none at all except for
the masking effect of the music.

Zane