The Ranger and the Pronto Are No More

Star images were fanned out to one side upon approaching focus.

If the scope was really warm for some reason, it would show a heat plume coming
out of one side of a star (all scopes will do this, by the way). Miscollimation
of this 140 would not show a fanned out image on one side. One other thing that
can cause a heat plume would be a really warm eyepiece inserted into a mirror
star diagonal.

Roland Christen

Oh and you've neve been off topic...ppplease......You were beating me for
something that was perfectly fine to talk about so I figured I'd do the
same. It's tough having to take that isn't it :-)

I see; so you perceived my point by point discussion of the inherent
difficulties with optimizing the Newtonian (OA or otherwise) design in general
as an attack on your DGM scope, so you thought you'd say something bad about a
TEC scope that you looked through once.

Nice, very mature, Mike. How old did you say you were?


rat
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"Alan French" wrote in message
.. .
"Stephen Paul" wrote in message
news

As I said originally, it looked to me like it was way out of
collimation.
Star images were fanned out to one side upon approaching focus. The
third
person in our group came to a similar conclusion independently. The one
thing we were unanimous on, was that for whatever reason, the "scope"
was
a
dog.

Stephen,

A couple of thoughts. Most refractors are corrected for coma, so the
collimation would, I think, have to be fairly far off to reveal coma. Of
course, you provide no idea on the magnitude of the fanning was, nor how
it
behaved as you went from one side of focus to the other. Do you remember
what the in-focus star images were like, or what happened just inside or
just outside of focus?

If folks want to evaluate refractors, and collimation might be an issue, a
Cheshire eyepiece should be part of their kit. Put a Cheshire in the
eyepiece holder, without a star diagonal, shine you red flashlight on the
45
degrees surface, and take a look at the reflections from the lens.

Like I said, it was too bad we didn't have the opportunity to troubleshoot
the scope unfettered by the owner.

If I weren't at least somewhat competent in understanding optics, I'd have
never given it a second thought, never looked back, and taken TEC off my
list of preferred apo manufacturers. I'm giving TEC the benefit of the
doubt, and considering it a given that the problem was something else. It
might have been more prudent, and better for TEC, if the owner didn't let
anyone look through it until whatever the anomaly subsided. Certainly if you
were to look through my 12.5" Dob before it had a chance to cool down. I'd
warn you about it. I'm not going to tell you that the views are fantastic
through the scope, and then show you heat plumes. Nor am I going to swear
that it's well collimated, and have you see poor images.

We don't all get sufficient opportunity to really sit and evaluate a scope,
and the onus is on the owner to assure that it is performing at its best
before inviting people over to look through it.. Especially at a star party,
where the skies are more important than the equipment used to observe them.
I am personally just as happy with a well collimated Chinese 100mm F5
achromat, as I am a well figured and collimated 12.5" reflector. I have no
axes to grind, or hidden agendas, and it hurts me to be considered a part of
a "tag team", just because I happen to think the OA scopes are fantastic
optically, and a good value for an unobstructed, color free telescope. If
someone says they're a good value and compare well with an apo of similar
aperture, or a standard Newt of somewhat larger aperture, I'm going to
agree. If I say they're a good value and compare well to an apo of similar
aperture, or a standard Newt of somewhat larger aperture, then Mike is going
to agree. Nothing I can do about that.

Anyway, in this particular thread, the only thing I'm guilty of, is getting
a bit caught up in someone elses fight, because he's a friend. I take the
TEC comment as flippantly, and spitefully made to indicate that first looks
don't always give adequate impressions. In the eyepiece, the scope appeared
a dog, and we gladly all walked away and went back to the OA6.5 and the
nearby 6" F13 achromat, rather than try to solve the problem. That said, not
knowing exactly what the problem was, I'd now want Yuri's guarantee that any
problem would be resolved, as I indicated.

So, at this point the only think left to do is get back on topic. It's easy
to agree that the Ranger and the Pronto are no more because of the 100mm F6
Chinese achros and the ED80 kill them in price competitiveness. However,
while the ED100 might be the deathnell of the TV102 on price, the DGM Optics
OA4 is still a better value, and anyone seriously looking at an ED100 on a
CG5/SVP, might want to consider the comparative luxury of the ultralight OA4
on a Dob mount. That's all I had to say on the subject in the first place.

As for me. the only apo that I am really interested in, is a light-weight
100mm F5, with a well machined OTA, lens cell, and focuser, mounted on a
UniStar Light Deluxe. I understand the Borg 100mm F5 ED is good match for
that criteria, but if I'm going to pay more than $500, nevermind a few
thousand, for a 100mm F5, it better be really well corrected for CA, SA,
Coma, and astigmatism, and I better see a difference on deep sky at low
powers. Otherwise, I can continue to convince myself to be happy with a
short tube achromat.

Regards,
Stephen

"Ratboy99" wrote in message
...

Oh and you've neve been off topic...ppplease......You were beating me for
something that was perfectly fine to talk about so I figured I'd do the
same. It's tough having to take that isn't it :-)

I see; so you perceived my point by point discussion of the inherent
difficulties with optimizing the Newtonian (OA or otherwise) design in
general
as an attack on your DGM scope, so you thought you'd say something bad
about a
TEC scope that you looked through once.

No, it was the way you did it that was bothersome. We've been through all
that discussion before. Other folks are tired of going through it all again
and I surely was. As I said, all I did was point out there was an option to
pick up a scope with similar aperture with an excellent professional review
(see S+T Oct 2003).

Mike.

No, it was the way you did it that was bothersome.

Other folks are tired of going through it all again
and I surely was.

Gee, that's the point that we have been trying to get across to you.

The reason that you in particular are tired of going through it is because it
happens to be the same old legitimate laundry list of the obstacles that a
Newt has to overcome in order to work as well as a refractor of the same
aperture, and you want everyone to think that just because it is an OA it
doesn't have to answer to the same maker.

Then you responded most immaturely by slamming a refractor that you looked
through once, and went on to say that you have no experience evaluating apos in
general.

There's nothing wrong with OA Newts, the problem is with you, your character
flaw is showing, and as such it is at the moment drawing flames.

I will be happy to try to reiterate what I have said in the thread so far ad
infinitum if that is what you are pushing for.

Or if you like you can just admit that you don't know what you are talking
about (ie: are a "ninny") and just "drop it."


rat
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"Stephen Paul" wrote in message

I'm giving TEC the benefit of the
doubt, and considering it a given that the problem was something else.

Given TEC's (Yuri's) hard won reputation for quality, I think your's is the
right chioce.

Regards,
Ed T.

"Ratboy99" wrote in message
...
No, it was the way you did it that was bothersome.

Other folks are tired of going through it all again
and I surely was.

Gee, that's the point that we have been trying to get across to you.

No you didn't read what I said. I already responded to your laundry list
and didn't feel the need to do it again. See the archives for the answers.
I brought up a valid point about the price performance on topic with the
post that was there. You guys dragged into this muck (and that's all this
really is).

went on to say that you have no experience evaluating apos in
general.

I never said that! In fact, if I recall, I believe I said I'd own an APO if
I could afford the big ones.


There's nothing wrong with OA Newts, the problem is with you, your
character
flaw is showing, and as such it is at the moment drawing flames.

I will be happy to try to reiterate what I have said in the thread so far
ad
infinitum if that is what you are pushing for.

Sounds like fun. lets keep doing it ;-)


Or if you like you can just admit that you don't know what you are talking
about (ie: are a "ninny") and just "drop it."

You really like name calling don't you. Who's the one that's immature. I
haven't sworn or called names. But you sure like too.




rat
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We don't all get sufficient opportunity to really sit and evaluate a scope,
and the onus is on the owner to assure that it is performing at its best
before inviting people over to look through it.

Sigh So, Stephen, was it a written invitation, or did you really just invite
yourselves? And further, while it might be better for TEC to make sure that all
of its optics owners cool down the scopes before using them, and use quality
eyepieces and diagonals, surely you recognize that it is impossible for a
company to dictate how its product is used (take guns for instance). If, as you
say, it is your intent to give TEC the benefit of the doubt (and knowing Yuri,
there is considerable latititude to accomodate the same), the comments
regarding TEC, have IMO been unfounded and undeserving thusfar of any mention
at all, considering the manner in which they have now been "qualified." That's
not what is called "giving the benefit of the doubt." When you give someone the
benefit of the doubt you bestow upon them the **grace** of not mentioning it
until you know for sure what is the issue. These start-up companies have enough
obstacles to overcome without us popping off at the mouth every time we
encounter an "unsubstantiated doubt."

That said, not
knowing exactly what the problem was, I'd now want Yuri's guarantee that any
problem would be resolved, as I indicated.

This is yet another example; you have now made this statement twice, what pray
tell is your motivation? You have already been told that TEC does stand behind
every instrument they make, so why do you infer that it somehow might it be
otherwise?

It sounds to me as if you are still criticizing TEC without having full
knowledge of the facts, both regarding the scope you looked through and the
integrity of the Company TEC itself and its willingness to stand behind what it
makes.

And again, why was it you couldn't ask the owner about the apparent problem,
but chose instead to leave and snicker about it in your car. No offense, but it
reads to me as if you guys already had some preconceived notions regarding what
you were expecting in the first place.

Could be a misperception on my part. I have no issues with you, but I do I find
it unfair that TEC is being maligned, however "innocently" for something that
it may have had utterly no control over.

rat
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Mike Fritterman writ:

But you sure like too.

It's "to" not "too."



rat
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You read but you don't listen Rat. He doesn't want your guarantee that TEC
would take care of a problem (if there was one) he want's TECs.

If it makes you feel any better, you can send the new scope my way. I'd be
more than happy to have it. Knowing Steve, I have a feeling he feels the
same way.

Funny, your making very similar arguments below to what I made. Where's
your proof that TEC is so great? Can you fill us in? Make sure you send
out all your notes, perform double blind tests etc etc....

Mike.


"Ratboy99" wrote in message
...
We don't all get sufficient opportunity to really sit and evaluate a
scope,
and the onus is on the owner to assure that it is performing at its best
before inviting people over to look through it.

Sigh So, Stephen, was it a written invitation, or did you really just
invite
yourselves? And further, while it might be better for TEC to make sure
that all
of its optics owners cool down the scopes before using them, and use
quality
eyepieces and diagonals, surely you recognize that it is impossible for a
company to dictate how its product is used (take guns for instance). If,
as you
say, it is your intent to give TEC the benefit of the doubt (and knowing
Yuri,
there is considerable latititude to accomodate the same), the comments
regarding TEC, have IMO been unfounded and undeserving thusfar of any
mention
at all, considering the manner in which they have now been "qualified."
That's
not what is called "giving the benefit of the doubt." When you give
someone the
benefit of the doubt you bestow upon them the **grace** of not mentioning
it
until you know for sure what is the issue. These start-up companies have
enough
obstacles to overcome without us popping off at the mouth every time we
encounter an "unsubstantiated doubt."

That said, not
knowing exactly what the problem was, I'd now want Yuri's guarantee that
any
problem would be resolved, as I indicated.

This is yet another example; you have now made this statement twice, what
pray
tell is your motivation? You have already been told that TEC does stand
behind
every instrument they make, so why do you infer that it somehow might it
be
otherwise?

It sounds to me as if you are still criticizing TEC without having full
knowledge of the facts, both regarding the scope you looked through and
the
integrity of the Company TEC itself and its willingness to stand behind
what it
makes.

And again, why was it you couldn't ask the owner about the apparent
problem,
but chose instead to leave and snicker about it in your car. No offense,
but it
reads to me as if you guys already had some preconceived notions regarding
what
you were expecting in the first place.

Could be a misperception on my part. I have no issues with you, but I do I
find
it unfair that TEC is being maligned, however "innocently" for something
that
it may have had utterly no control over.

rat
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