Grizz
Carpal Tunnel
Reged: 04/24/03
Posts: 2172
Loc: Waldwick,New Jersey USA
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Congrats and good luck! I still have my finger on the trigger for a 12".... 
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Craig
LX200GPS 10" UHTC SMT
ETX90EC
Orion ED80 APO
Meade LPI Canon 10d Meade DSI
My Photo Gallery
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jrcrilly
Refractor wienie again
Reged: 04/30/03
Posts: 22472
Loc: NE Ohio
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Quote:
I ordered the 14" RCX from Anacortes. Delivery will be in March.
Great! I hope you'll report on your experiences here first.
Although my experience with pre-ordering hasn't been encouraging (ordered a 14" from Meade in August for December delivery, received scope the following August), I think Meade intends to come pretty close to meeting their predicted dates this time.
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John C
Urban Observatory
Tele Vue Pronto
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 152ED F/9 "APO"
152mm F/10 achromat
Tak CN-212 8" F/12 classical Cass/ F/4 Newt
Teeter 20" F/3.8 truss Newt w/ServoCat
LXD750, EM-200, CI-700
ST-10XME
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Rusty
Postmaster
Reged: 08/06/03
Posts: 16406
Loc: Brooker, FL
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The price drop makes the 16" SCT suddenly very attractive.... 
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N11GPS Fastar
TOA-130S
MK66 Std
Vintage C5
Megrez II 80mm ED Triplet APO
SolarMax 40
NJP Temma II
Sirius EQ-G
ST8XE/CFW-8(LRGBHa)/AO-7/DF-2/STV Dlx/ST237a/350D (Unmodded)/Mallincam Color Hyper Plus/DSI III Color/DSI II Pro
Two not-spoiled Golden Retrievers - Maggie and Casey
Sometimes I think we're alone in the universe, and sometimes I think we're not. In either case the idea is quite staggering. - Arthur C. Clarke
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Anonymous
Unregistered
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Yeah, here's Roland Christen's take on it from the the Meade-RCX400 group on yahoo.
Quote:
If the CO is around 50%, then there is an immediate 25% light loss at
the focal plane. Add to that the efficiency of the mirrors and
corrector, around 80%, the light throughput will be only 60%, which
makes a 12" equivalent to a 9.3" clear aperture. The working F-ratio
will then be F10.3, rather than the stated F8. Furthermore, the peak
of the central Airy disc will contain only 50% of this energy, with
the rest going into the diffraction rings, mostly the first one. That
means if there is the slightest atmospheric disturbance, the star
size will broaden out to twice normal size, and the effective
resolution for tiny detail will be equivalent to an unobstructed 6"
instrument, however with the light grasp of a 9.3" scope.
One thing that I disagree with in their ads is the spot size of an
equivalent classical Cassegrain. One can design and build an F8
Cassegrain which will have much smaller off-axis coma. It all depends
on the F-ratio of the primary and the magnification of the secondary.
Tony Hallas, for instance, has a classical Cassegrain, 14"F8, which
does a very good job with his ST10XE camera, as well as 35mm film
format. Coma is essentially absent in any of his images. The
secondary mirror on his scope is 6" diameter, which makes it just
under 43% obstruction.
Lastly, one can design a 12" Mak-Cass with zero coma and very nice
flat field at F8 with less than 36% obstruction and still cover a
35mm format with tight star images. In fact, I built a 10" F9 with
only 30% obstruction that has been used for imaging with an ST10XE
camera by Trent Kjell. Even though theoretically it has some field
curvature, in actual use, the star images are pristine right into the
corners of the format, and bright stars do not bloat the way they
will in a 50% obstructed scope.
If you want to go further down in central obstruction, I would go for
a Mak-Newt. I recently had a chance to play with a 14" F4 Mak-Newt
built by Mathais Wirt using Russian optics. This scope had only a 20%
obstruction. The star images were very tight into the corners of my
ST10XE and with a simple field lens would easily cover a 35mm chip
size. I was able to do totally unguided imaging with this scope
because faint stuff registered in seconds. I fully expected the tube
assembly to be a brute, but was surprised that I could easily lift it
myself - weight was around 54lb. A 12" version of this scope would be
ideal for almost any kind of imaging, as well as visual. Not as
compact as the Meade, but not all that bad size wise.
Roland Christen
Personally, if it looks like a duck, walks like a duck and quacks like a duck, it definitely ain't no swan!
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darylf96
Pooh-Bah
Reged: 08/28/04
Posts: 1246
Loc: Danville, California
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Meade has outdone itself. The 12 inch will be my retirement scope. First, I must find my piece of land in the sierras at the top of a slope with rocks and no trees, where I can park a trailer and construct an observatory. I can't wait!
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Intes Micro MN66 - Meade 10" SCT
Skywatcher 150mm f8 Achro
CGE Mount - DiscMount DM-6 on Meade Field Tripod
with SkyCommander DSC
Lumicon 80mm Super Finder
ED80 w MoonLite focuser on CG5A-GT mount
WO ZenithStar ST 80mm/WO B-viewer
Astro-Tech AT80 Refractor f6.9 APO
On SV M1 mount & Grab-Go Tripod
Stellarvue 20x85 binos - Unimount
Kunming United Optics 7x50 binocs
Canon Rebel XT, Canon 20D, SB ST8XE
Orion DSCI, Meade DSI
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Anonymous
Unregistered
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Astronomics - I ordered an RCX 400. I'm new at this. I ordered after research and some intuition. I know I'm gambling a bit. With all of that in mind I was reading another thread on this forum about the LX 200 and its plastic gears and how some users feel the scope is built cheaply in some regards. Does the RCX have plastic gears like the LX 200? Will the RCX be as flimsy as some people think the LX200 is? thank you
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Anonymous
Unregistered
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RollyC: I'm confused how do you know all of this (for sure) if there isn't even a scope to examine? Just from the written specs? Is there not more to it than that? It sounds like you're saying (though I'm not following most of what you are saying) that you are not at all endorsing the design of the RCX 400 (a dog in your opinion?). Confused how absolute one can be from specs, but again, I'm not the expert. Can you explain for the novices ?
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Anonymous
Unregistered
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First, the information I quoted is from Roland Christen, founder of Astro-Physics, who is seen as one of the pre-eminent authorities within the amateur astronomy community when it comes to telescope design. That message also contains a link to the yahoo group Meade-RCX400, http://groups.yahoo.com/group/Meade-RCX400/ , which has some in depth discussions on Meade's new RCX400.
Secondly, all scopes obey the laws of physics and with programs like ATMOS an optical designer can quickly determine a scope's performance by simply entering the scopes specs. Roland would've simply keyed the specs for a typical Ritchey-Chretien, plus corrector, and the program was able to calculate the scopes performance and compare it to other designs. I would recommed "Telescope Optics" by Rutten & van Venrooij if you want a reference to draw from. Here's a link to the publisher's website.
Thirdly, I'm not endorsing anything. I'm just presenting additional information that will help potential purchasers in making a more informative choice. The majority of what I've seen here has been centered around information provided by Meade and one of their dealers. They've put out the Ritchey-Chretien bait and a lot of folks are biting. Know what you're getting into before you get reeled in otherwise it becomes a costly experience.
The bottom line is this, if Meade delivers what they're claiming the RCX-400 will make a wonderful astrograph but visually the scope will perform poorly. Furthermore, Ritchey-Chretien scopes are very difficult to make due to tight tolerances of the design and some of us remain sceptical that a mass market telescope producer can pull this off.
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sixela
Postmaster
Reged: 12/23/04
Posts: 9499
Loc: Boechout, Belgium
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Quote:
RollyC: I'm confused how do you know all of this (for sure) if there isn't even a scope to examine? Just from the written specs?
Well, Roland's main gripe was the central obstruction that was even bigger than on SCTs (note that at large apertures, I don't think SCT's central obstructions are that troublesome, but with even bigger COs than those, those marketing aperture numbers start to be oh so slightly misleading...), and that's not really inconspicuous  .
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400mm f/4.46 David Lukehurst truss Dobsonian on Tom Osypowski equatorial platform
Orion Starblast (114mm f/4 reflector, Alt/Az)
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Mike28
Carpal Tunnel
Reged: 06/21/03
Posts: 2889
Loc: Morris County,NJ
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But how quiet is it when slewing?
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Mike
'The only reason for time is so that everything doesn't happen at once.” Albert Einstein
NS11GPS/Sky align
TAKAHASHI TOA150F
Celestron 80ED
TV Pronto
Burgess Bino
Coronado Ha PST
CGE mount
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sixela
Postmaster
Reged: 12/23/04
Posts: 9499
Loc: Boechout, Belgium
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Quote:
The bottom line is this, if Meade delivers what they're claiming the RCX-400 will make a wonderful astrograph but visually the scope will perform poorly.
Poorly *compared to differently optimised designs at identical aperture* - an important qualifier (unless visual observation is your only criterion, in which case the other designs are optimised more to your liking).
Given the aperture of the bigger models, I don't think they'll be limited by anything more than seeing in anything but the rarest circumstances, so in that sense they won't "perform poorly" in an unqualified sense.
And probably not all of the RCX400s have the same central obstruction ratio - the photos over at the OPT site for the 12" don't show a central obstruction ratio of anything like 50%.
Mind you, I'd never buy one -- too much electronics and "auto" everything (I see enough electronics at work and I distrust Mk.I firmware and new features in anything as a second nature), a large central obstruction, a mount based on design principles I do not favour, irritating ghee-whizz marketing.
But I see that as a matter of personal taste: there's no need to inflate its drawbacks to give oneself a good conscience.
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400mm f/4.46 David Lukehurst truss Dobsonian on Tom Osypowski equatorial platform
Orion Starblast (114mm f/4 reflector, Alt/Az)
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Strgazr27
Scope Junkie
Reged: 10/04/04
Posts: 6023
Loc: StonyHill Observatory
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Shouldn't the central obstruction be in relationship to the aperture? I understand an 8" scopes secondary would be smaller than the 12 or 16's but to me the ratio should be the same unless I'm missing something.
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Bobby
StonyHill Observatory
Atlas w EQMOD
Vixen R200SS
Orion ED-80
AT-111
AT66-ED
QHY-8
SSAG
YAHOO TMB 130SS Group
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sixela
Postmaster
Reged: 12/23/04
Posts: 9499
Loc: Boechout, Belgium
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No, it depends on how long they want to make the tube and how they chose to make the primary (I'd say "slow" vs. "fast" but the corrector+primary doesn't focus at a single length).
I wouldn't be so sure as to say they're all the same but simply scaled up and down from a base model -- certainly the Celestron SCTs are anything but identical models scaled up from a C8 (certainly not the C9.25!).
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400mm f/4.46 David Lukehurst truss Dobsonian on Tom Osypowski equatorial platform
Orion Starblast (114mm f/4 reflector, Alt/Az)
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Strgazr27
Scope Junkie
Reged: 10/04/04
Posts: 6023
Loc: StonyHill Observatory
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I geuss I understand to a point although the 12" and up don't look that much longer than the 10". The 12 also looks like it would swing through the forks unline the LX200 12". I would have thought that to keep the same F/ speed the secondary would be in proportion to the primary although as you say the Cel. 9.25 is a good example.
I didn't say they were scaled up like the 8's. I wouldn't think so as they are supposedly a different optical design. (Or at least Meade says they are
I don't know if it's any clearer but I appreciate the answer.
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Bobby
StonyHill Observatory
Atlas w EQMOD
Vixen R200SS
Orion ED-80
AT-111
AT66-ED
QHY-8
SSAG
YAHOO TMB 130SS Group
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Anonymous
Unregistered
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Here's a couple of photos to give you an idea how large the CO is.
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Strgazr27
Scope Junkie
Reged: 10/04/04
Posts: 6023
Loc: StonyHill Observatory
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If that's the 12" that CO looks to be at least 50%. At least from what I can judge from those 2 pics. Anybody else agree?
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Bobby
StonyHill Observatory
Atlas w EQMOD
Vixen R200SS
Orion ED-80
AT-111
AT66-ED
QHY-8
SSAG
YAHOO TMB 130SS Group
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Anonymous
Unregistered
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Grizz, RollyC, Stargzer: The purpose of this forum, at least for me (and I assume for others) is to obtain good credible, specfic information. As I tried to separate fact from fiction re the RCX I was (kindly) chastised just a bit for obsessing about the pros and cons of the RCX 400. I ended up just saying, "whatever" and I'll give the RCX 400 a shot. Now with RollyC's information (which is touted as absolute and since I don't know, I'll have to assume it is), the RCX is categorized as a scope that won't for the same dollars perform visually as well as other scopes though for astrophotography it will be fine. The deal is this: I can buy any scope I like. If I make a mistake no one dies. Money isn't a huge issue but I'm not going to spend more than the RCX 400 10" is going for. Based on RollyC's negative take on the scope, can I just get a clear recommendation what one should buy if not the RCX 400? Isn't that the real point here? If the RCX 400 is not all its cracked up to be (and without actually saying so, many people on this forum seem to say that Meade is "nearly" lying), what is the alternative? I'm trying to get to solutions and not just problems. Give me some real advice here and I'll toast you at dinner tonight!
Thanks everyone: Frustrated and starting not to care anymore
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Strgazr27
Scope Junkie
Reged: 10/04/04
Posts: 6023
Loc: StonyHill Observatory
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Quote:
Grizz, RollyC, Stargzer: The purpose of this forum, at least for me (and I assume for others) is to obtain good credible, specfic information. As I tried to separate fact from fiction re the RCX I was (kindly) chastised just a bit for obsessing about the pros and cons of the RCX 400. I ended up just saying, "whatever" and I'll give the RCX 400 a shot. Now with RollyC's information (which is touted as absolute and since I don't know, I'll have to assume it is), the RCX is categorized as a scope that won't for the same dollars perform visually as well as other scopes though for astrophotography it will be fine. The deal is this: I can buy any scope I like. If I make a mistake no one dies. Money isn't a huge issue but I'm not going to spend more than the RCX 400 10" is going for. Based on RollyC's negative take on the scope, can I just get a clear recommendation what one should buy if not the RCX 400? Isn't that the real point here? If the RCX 400 is not all its cracked up to be (and without actually saying so, many people on this forum seem to say that Meade is "nearly" lying), what is the alternative? I'm trying to get to solutions and not just problems. Give me some real advice here and I'll toast you at dinner tonight!
Thanks everyone: Frustrated and starting not to care anymore
Seems like you may need that drink sooner than tonight
What would I do, which is what I am doing. I am waiting until the scopes are out, used and tested. And that all the previously mentioned things are tested by impartial people with the knowledge to give an impression. You may be able to spend whatever you want on a scope. I for one cannot. If the RCX is all Meade says it is than the Classic will be sold and I will purchase either the 10 or 12" RCX. But absolutely not BEFORE that point.
You could say to heck with everybody and just do what you want also. What we are doing IS providing exactly what you are looking for. A large varied gathering of info. Perhaps it would have been better to wait with your order until all this info was clarified and proven/disproven.
JMO
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Bobby
StonyHill Observatory
Atlas w EQMOD
Vixen R200SS
Orion ED-80
AT-111
AT66-ED
QHY-8
SSAG
YAHOO TMB 130SS Group
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jrcrilly
Refractor wienie again
Reged: 04/30/03
Posts: 22472
Loc: NE Ohio
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Quote:
Give me some real advice here and I'll toast you at dinner tonight!
I can point out a few things. For one, there's a tremendous amount of noise on the various Groups regarding how poorly such a telescope would perform visually if it had a CO of 50%. Since it doesn't, this needn't be of much concern. It DOES have a relatively large CO, as do the SCT's. I think everyone agrees that an SCT isn't as good a visual instrument as an APO of similar aperture - that's to be expected from optical and physical parameters. These won't be, either. Most folks acknowledge that to achieve apertures of 8" and larger the tradeoffs of obstructed telescopes are tolerable (as indicated by the vast difference in numbers of 8" - 16" SCT's compared to 8" to 16" APO's). They still sell very well, and have a huge base of satisfied users. The RCX will have a little more CO than the SCT's; it's likely that expert observers will be able to see the difference - but it'll be subtle. As in all designs, optimizing for one use will compromise another.
We know the beta testers (the only folks who have looked through these things) aren't using words like "terrible" or "poor". The reports I've seen have been most encouraging.
The substantial issues here involve the fact that this is a new startup product. There are risks that early units will suffer from unexpected problems either mechanically, electrically, or optically. All the recent new products in this market segment have exhibited some degree of teething pains, some easily solved and some more involved. If you are willing to accept the risk of some inconvenience, and trust Meade to deal with such issues, then you might be a good candidate for one of these. I've been an early adopter of several new models recently and all have worked out well for me - your luck could be different.
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John C
Urban Observatory
Tele Vue Pronto
A&M/Astreya 76mm F/6 APO
TMB/LOMO 80mm F/7.5 APO
Tak FSQ-106N F/5 APO
Meade 152ED F/9 "APO"
152mm F/10 achromat
Tak CN-212 8" F/12 classical Cass/ F/4 Newt
Teeter 20" F/3.8 truss Newt w/ServoCat
LXD750, EM-200, CI-700
ST-10XME
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Mike28
Carpal Tunnel
Reged: 06/21/03
Posts: 2889
Loc: Morris County,NJ
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Hi John: It seems thought that a bigger external power system will be needed what with the internal dew coil and the fan both using the same power source. would this drain the battery quicker when viewing in the field? I know running off of house current would not be a issue. Are there any separate power ports to run these extra's without taking power from tracking,focusing? And has the slewing noise been greatly reduced? I have been looking at the RCX400 with interest but there does seem to be many questions here.
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Mike
'The only reason for time is so that everything doesn't happen at once.” Albert Einstein
NS11GPS/Sky align
TAKAHASHI TOA150F
Celestron 80ED
TV Pronto
Burgess Bino
Coronado Ha PST
CGE mount
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