MEMO to Meade: How to write an honest news release

On 1 Feb 2005 21:52:42 -0800, wrote:

It was a rhetorical question Roland. The point was there is more than
one way to make a mak. They are all maks. I agree Meade should put a
modifier on the end but they are not entirely out of line in calling
this telescope a Richey.
If on the other hand it does not use two hyperboloid mirrors then you
are correct and I completely agree.
Ian Anderson
www.customopticalsystems.com

The only people effected by Meade using the term, R-C are those who
dislike Meade. If the scope offers the same level of correction
as and R-C, does it really matter what it's called? If they were
trying to pawn-off one of their standard SCTs, that would be
different. Take a look at eyepieces to see where the idea of
"creative" uses of proper names has happened.
-Rich

RichA wrote:

The only people effected by Meade using the term, R-C are those who
dislike Meade. If the scope offers the same level of correction
as and R-C, does it really matter what it's called? If they were

Remind me to sell you some (what most of us call) silver, but,
unbeknownst to you, say it is called "gold".

RichA wrote:
On 1 Feb 2005 21:52:42 -0800, wrote:


It was a rhetorical question Roland. The point was there is more than
one way to make a mak. They are all maks. I agree Meade should put a
modifier on the end but they are not entirely out of line in calling
this telescope a Richey.
If on the other hand it does not use two hyperboloid mirrors then you
are correct and I completely agree.
Ian Anderson
www.customopticalsystems.com


The only people effected by Meade using the term, R-C are those who
dislike Meade. If the scope offers the same level of correction
as and R-C, does it really matter what it's called? If they were
trying to pawn-off one of their standard SCTs, that would be
different. Take a look at eyepieces to see where the idea of
"creative" uses of proper names has happened.
-Rich

Yes, let us not consider the issue, but rather those who raise the
issue. That way we can have a nice discussion about personalities,
instead of principles. It's a nice hook to pull the discussion off track.
I say blame the media. Making a telescope is hard work. Why do these
people hate freedom?

Uncle Bob

(Chris1011) wrote in message ...
Didn't you release an F14.6 mak cass with an aspheric primary. Was
this a true Mak Cass Or did you just call it that?

Of course it's a true Mak-Cass. What else would it be? In fact, Maksutov
himself calculated several designs with aspheric primary elements. The main
advantage for this design is the very small secondary that results with zero
coma.


Hum, just for the sake of clarity...

The RC nomenclature applies, for hystorical reasons, to any
(cassegrain) optical system with 2 powered reflective surfaces
achieving aplanatism and zero 3rd order spherical aberration. It
happens, however, thatyou can only achieve that with two hyperboloidal
surfaces.

The Maksutov-Cassegrain name applies to any cassegrain optical system
which employs a spherical achromatic meniscus (defining the inlet
pupil of the system) and two powered reflecting surfaces, achieving
both correction for longitudinal chromatic aberration and 3rd order
spherical aberration (at one wavelength at least, there might be a
very small residual spherochromatism). As one can see, there is no
claim of aplanatism within the definition itself. You can achieve
aplanatism (at least within a comfortably large FOV) by either having
4 powered surfaces (refractive and reflective) having different radii
of curvature or by having an aspherical surface (I gather an
ellipsoidal one) as primary and 3 different radii of curvature.

The advantage of the AP/Aries ones are that they minimized CO (by a
small amount) for any separation between primary and secondary thus
achieving a (slightly) faster system with smaller CO within the same
OTA length constrains.

Reg's

Andrea T.

On Thu, 03 Feb 2005 10:49:44 -0800, Uncle Bob
wrote:

RichA wrote:
On 1 Feb 2005 21:52:42 -0800, wrote:


It was a rhetorical question Roland. The point was there is more than
one way to make a mak. They are all maks. I agree Meade should put a
modifier on the end but they are not entirely out of line in calling
this telescope a Richey.
If on the other hand it does not use two hyperboloid mirrors then you
are correct and I completely agree.
Ian Anderson
www.customopticalsystems.com


The only people effected by Meade using the term, R-C are those who
dislike Meade. If the scope offers the same level of correction
as and R-C, does it really matter what it's called? If they were
trying to pawn-off one of their standard SCTs, that would be
different. Take a look at eyepieces to see where the idea of
"creative" uses of proper names has happened.
-Rich

Yes, let us not consider the issue, but rather those who raise the
issue. That way we can have a nice discussion about personalities,
instead of principles. It's a nice hook to pull the discussion off track.
I say blame the media. Making a telescope is hard work. Why do these
people hate freedom?

Uncle Bob

Look at it this way; If the scopes turn out to be dogs, the Meade
attackers will get another shot at it, and will have legitimate
reasons for attacking, unlike now.
-Rich

Sounds good, Rolland. Can I be on the list?

RCK


Chris1011 wrote:
By Meade's own statement, this is not even remotely like an R-C.


Does it make a difference? What is your verdict after using the 'scope
-- is it a good telescope for the money, or not?

Hey, if I offer an F8 Mak-Cass corrected for coma, can I call it an RC? They
both work the same and supply the same results.

RC

wrote
......
The only two aberrations R-C suffer from are astigmatism (only
correctable by adding a near-focus plano concave lens)
and curvature of the field (correctable if you are ready to accept
obstructions in 60% range).
.......

I've used a 10" F/9 and a 20" F/8 RC Cass for 13 years. Of the two RC design
problems you mention astigmatism is the most important issue with actual
observing, both visual and imaging. It is always noticable. Field curvature
in the 10 is just visable in the outer part of the field in a low power
eyepiece like a 35mm Panoptic. With the 20" there is no visual effect. It's
been about 7 years since I've used film with the 20" but I did look for
problems on 4x5 inch negatives back then and saw none. On the 20" I've seen
no sign of problems on the 12x13 arc minute field covered by my STL-1301E
camera.

George Normandin