jrcrilly
Refractor wienie again
Reged: 04/30/03
Posts: 22470
Loc: NE Ohio
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Quote:
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?
Hi, Mike.
Meade claims (and it makes sense to me) that because the heater is internal it will actually use less power than the heaters we normally add, so I don't see that as an issue. Small fans don't draw much power and are normally not used during observing, so I doubt that'll be an issue either (nobody has ever complained about current drain from the 7" Mak model which uses a similar fan).
I wouldn't expect the motor noise to be any worse (or any less) than the current LX200GPS. It didn't bother me when I had one. It IS the best-selling unit of its type so it must not be a very big deal generally.
There are real issues to be concerned about with a new model, especially with the increased dependence on the electronics in this one. I'm no Meade cheerleader, and I haven't pulled the trigger on this new model myself - but folks seem to be spending a lot of time worrying about non-issues.
The bottom line is that most of the noise is coming from folks who would never buy a fork-mounted CAT of any type. I think it would be better to hear more from those who have a use for this type of instrument and are comparing it to what else is available in the price class.
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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: Then the main concern is the visual issue. Since I am a visual observer as opposed to astro-photography, then this scope may not be good for me. I have owned 3 CATs so far and found them excellent for visual viewing. Too much electronics can take away the enjoyment of this hobby. My NS11GPS though a great scope cannot be used manually like my old LX200 so I am dependent on keeping the electronics and motors functioning normal and so far it's been two years now I have not had any problems. That is a good track record. As much as Meade put a bad taste in my mouth with their lawsuits and repair issues, their products are good as Celestron and Orion,etc. The new scope looks promising but we still need input from a owner who has one and I know its too soon to tell. I can wait a year. My current equipment will keep me going so there is no 'gotta have it' itch. The big thing is the cost. WAY big! Plunking down the cash then being dissapointed as suggested is another thought to consider. I can wait.
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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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jrcrilly
Refractor wienie again
Reged: 04/30/03
Posts: 22470
Loc: NE Ohio
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Quote:
Hi John: Then the main concern is the visual issue.
Hi, MIke.
There are some features that sound great for visual use but it'll be more exciting for the casual imaging guys.
For the first time ever, I actually have gear that lets me take pictures that please me. I'd hate to tear it down and start over. I'm intrigued but probably won't jump just yet.
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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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Quote:
Quote:
Hi John: Then the main concern is the visual issue.
Hi, MIke.
There are some features that sound great for visual use but it'll be more exciting for the casual imaging guys.
For the first time ever, I actually have gear that lets me take pictures that please me. I'd hate to tear it down and start over. I'm intrigued but probably won't jump just yet.
I agree. it is a intriguing scope. But with what equipment I have now I am quite happy - if not a little light in the wallet now. 
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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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Anonymous
Unregistered
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JRCrilly
Can you or someon else comment specficially on the following statements from this thread:
1. " 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."
JRCrilly: so you're saying that Ronald Christain's entire argument against the RCX is based on a false premise of a CO of 50%? I'm confused. He goes into great detail about how the scope is no good because of its CO. How could that be if he's quoting the size of the CO incorrectly?
2.
"One thing that I disagree with in their ads is the spot size of an
equivalent classical Cassegrain"
What is his point here and argument?
3.
"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."
You mean to say all one does is enter in specs and presto, instant review even without seeing the scope? Please explain. Sounds too good to be truel.
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jrcrilly
Refractor wienie again
Reged: 04/30/03
Posts: 22470
Loc: NE Ohio
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Quote:
JRCrilly: so you're saying that Ronald Christain's entire argument against the RCX is based on a false premise of a CO of 50%? I'm confused. He goes into great detail about how the scope is no good because of its CO. How could that be if he's quoting the size of the CO incorrectly?
Maybe he was thinking of a different telescope.
Quote:
2.
"One thing that I disagree with in their ads is the spot size of an
equivalent classical Cassegrain"
What is his point here and argument?
Dunno - you'd have to ask him.
3.
Quote:
"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."
You mean to say all one does is enter in specs and presto, instant review even without seeing the scope? Please explain. Sounds too good to be truel.
There might be something to it - but of course Meade hasn't released any specs to the public. I doubt they have released them to competing telescope manufacturers either (which Roland is) so there's no reason to think his guesses about the other specs are any more accurate than his CO figure which is obviously wrong.
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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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Strgazr27
Scope Junkie
Reged: 10/04/04
Posts: 6023
Loc: StonyHill Observatory
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MB,
Nowhere in the post from Roland do I see him say it is 50%. What I read was...."IF the CO" 2 Letters that change the whole meaning of the statement. Therefore if it's less than 50% he's not really wrong due to the fact he said "IF". If, there's that word again, it turns out it is 50% Than more than likely, his observations, as well as others with as much experience and knowledge, would seem to be true.
His point about the spot size is that Meade used a pattern from a "Typical" F8 SCT. My question is, are they using the F8 as a comparison to the RCX to keep the F ratios the same. How many mass produced SCt's do you know of that are F/8? His point was, and he states it right there in print "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." What he's saying is the spot diagram is a generic outlook. Why not compare the RCX's Spot diagram to an F8 SCT such a Roland speaks about? Could it be the spot pattern would seem much less impressive?
"ATMOS an optical designer can quickly determine a scope's performance by simply entering the scopes specs." Perhaps the operative/missing word here is "Theoretical". There are lots of Optical design programs that will tell you how something should perform. The difference is in real world applications. This can be used to compare performance strictly from a theoretical optical standpoint. Nowhere do I see the word review used or even sarcastically implied.
CS's
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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
Edited by Strgazr27 (01/17/05 12:34 AM)
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sixela
Postmaster
Reged: 12/23/04
Posts: 9499
Loc: Boechout, Belgium
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Quote:
Quote:
"One thing that I disagree with in their ads is the spot size of an equivalent classical Cassegrain"
What is his point here and argument?
Roland's point is that a classical SCT can be optimised to yield less coma than is shown in the diagram. Of course, the masses, unlike Roland, are bound by commercially available SCTs, so there's a merit to Meade's point as well.
But beware the marketing use of "typical" in the phrase "typical SCT". That doesn't sound like they selected even *their* best SCT design with respect to coma, let alone that of someone else.
And let's face it, for *visual* use they inflate the importance of coma in the typical f/10 SCT -- you'd need quite a flabergastingly good eyepiece to notice coma in an f/10 or f/12 (certinaly given that their baffling restricts the maximum unvignetted true field at prime focus).
Quote:
You mean to say all one does is enter in specs and presto, instant review even without seeing the scope? Please expl in. Sounds too good to be truel.
It's not -- except that the "specs" you have to enter include precise details about the mirror and corrector figuring, and these are usually not public.
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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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JerryWise
Postmaster
Reged: 12/26/03
Posts: 6880
Loc: Lexington, SC
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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 
Hello MB. I think your points are very good. You are results oriented and want to get to the point. Saves a lot of time if the process can be shortcut.
A lot of the selection process depends on the individual. Background, experience, preferences, expectations.
Maybe a little more about where you are in the hobby would help:
What background brings you to an RCX descision. Have you been observing for some time or is this your first venture into astronomy? Are you very familiar with observing, the sky, optical theory, precise mechanical drives, atmospheric effects, etc.
Do you want to look at objects or photograph them? (Most do not know this answer for sure until they have had several scopes.)
Are you handy with tools and patient with mechanical devices that do not meet your needs without modification. (The truth of this comes when mating a fork mount to an aftermarket wedge or just doing a colimation.)
It's always good to know what you want to look at. Is your interest in deep sky, or planets etc.
Without knowing a little about your desires the good folks here may not provide you with the best advice. In some situations a dob is the best choice, others a refractor and still others a goto like the RCX/LX/Nexstar family.
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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jrcrilly
Refractor wienie again
Reged: 04/30/03
Posts: 22470
Loc: NE Ohio
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Quote:
Yeah, here's Roland Christen's take on it from the the Meade-RCX400 group on yahoo.
I notice that today he buried, in the middle of another long paragraph describing how bad a 50% obstructed scope would be, an acknowledgement that this wouldn't apply to the RCX since it isn't 50% obstructed.
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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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Anonymous
Unregistered
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Hello Meddyn:
Quote:
Hello MB. I think your points are very good. You are results oriented and want to get to the point. Saves a lot of time if the process can be shortcut.
A lot of the selection process depends on the individual. Background, experience, preferences, expectations.
Maybe a little more about where you are in the hobby would help:
What background brings you to an RCX descision.
I ground a 4" mirror when I was just a kid and have been bit for 40 years. But not time to seriously have a hobby. Fooled with "toylike" scopes, but finally my wife bought me the real thing: An LX200. Prior to confirming order she wanted me to confirm it is what I wanted. Then the RCX came out. And the rest is "history"
Quote:
Have you been observing for some time or is this your first venture into astronomy?
A bit of both. I have been observing casually with a very bad toylike scope for years, but I don't think its even worth consdering. I'm a novice, trying to learn as much as possible now
Quote:
Are you very familiar with observing, the sky, optical theory, precise mechanical drives, atmospheric effects, etc.
I'm learning each day about coordinates, a bit about optical theory, I don't know much about drives other than what I'm learning about GEM vs. alt/az verses wedge (understand that basically) and understand to some degree atmospheric affects (but only basically and I'm in a big city suburban area with considerable and significant light pollution - my hope is to collect as much light as possible through photography but of course understand that I'll collect light pollution as well - have some viewing locations in mind "up north" and might buy a second home somewhere for this purpose but that's off in the future)
Quote:
Do you want to look at objects or photograph them? (Most do not know this answer for sure until they have had several scopes.)
I hope to ultimately photography them as photography is a long time hobby of mine (know more about that than astronomy, but still I'm no Ansel...) I still like observing of course, but photography is hard to resist. Have many digital SLRs, film cameras, etc. all Nikon.
Quote:
Are you handy with tools and patient with mechanical devices that do not meet your needs without modification. (The truth of this comes when mating a fork mount to an aftermarket wedge or just doing a colimation.) [/ quote]
I'm patient, that is for sure. I'm somewhat handy but I call people to build my basement, I didn't build it myself (as an example) but I did create all of the blueprints (former architectural education).
Quote:
It's always good to know what you want to look at. Is your interest in deep sky, or planets etc.
Such hard questions because I love it all. There's nothing like Saturn - I could look at that all day, but to actually photograph a Nebula, that would be something. So I'd have to say I'm split.
Quote:
Without knowing a little about your desires the good folks here may not provide you with the best advice.
I hope the above helps those willing to share advice with me.
Quote:
In some situations a dob is the best choice, others a refractor and still others a goto like the RCX/LX/Nexstar family.
I've looked through DOBs, gotos and refractors at various times. I'm interested in transporting my scope (at first locally) and maybe at some time to some vacation home via plane but I'm a bit daunted as to the safety of th transporation and the time of breakdown, set-up, etc.
Thank you for all of your help.
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Anonymous
Unregistered
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Roland's company (or he works for a company) makes a competitve scope to the RCX?
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Suk Lee
Post Laureate
Reged: 10/07/03
Posts: 4315
Loc: Pleasanton, CA
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Roland is the owner/chief optician of Astro-Physics.
They currently make Apo refractors and have made Maks and Mak Newts in the past. They also make terrific Goto mounts.
He doesn't make RCs, but his refractors have an emphasis on astrophotography.
www.astro-physics.com
Cheers,
Suk
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http://www.siliconvalleyskies.com
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JerryWise
Postmaster
Reged: 12/26/03
Posts: 6880
Loc: Lexington, SC
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You may be interested in this post in the refractor forum. While for a different scope, the advice is top notch:
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/311755/page/0/view/collapsed/sb/5/o/all/fpart/1/vc/1
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Jerry
LX200ACF 14", Tak FS 152 & TOA 150
AP-1200 & Mach1
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melvy
professor emeritus
Reged: 10/17/03
Posts: 710
Loc: Shoreline WA
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No wonder Roland is playing up the disadvantages of the RC design. I am sure AP feels threatened by the RCX. The RCX has the potential to cut down the waiting list by at least 3 or 4 months (J/K of course)
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WO Megrez 80 SAPO
WO 66 SD APO
TMB SS 130 APO
C8 XLT SCT
Losmandy GM-8 w/Gemini
Losmandy G-11 w/Gemini
Discmount DM6
SBIG ST-2000XM/AO7
Marc Elvy
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Rhadamantys
sage
Reged: 04/25/03
Posts: 214
Loc: France
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This telescope has raised many questions on my side of the Atlantic. Thierry Legault (Deep Sky & Planetary imager using a 12" Meade SCT among different scopes) is also very suspecicious about the Ritchey-Chrétien denomination. I also happen to share his analysis which is mostly based on cost and convenience of production.
1) It is extremely costly (many hours, therefore $$$$$) to make a good window plate for any Cassegrain (See "How to make a telescope" by Texereau or ask any ATM who has tackled such a project). Why bother with it on a Ritchey-Chrétien when a spider is far cheaper?
2) Meade has the know-how to make Schmidt-Correctors. It is not very difficult to make a Schmidt-Corrector for a F/8 Aplanatic Schmidt-Cassegrain when you are already making a Schmidt corrector in the same apperture range for f/10 SCTs: you already have the plate glass available, only one surface differs and only slightly. It would save a lot of money vs the tremendous cost of aspherising two mirrors (one which happens to be a particulary fast primary) to produce a Ritchey-Chrétien. As a bonus, the aplanatic SCT will have less off axis astigmatism than a comparable Ritchey-Chrétien. You can produce a very good astrograph based on the aplanatic SCT.
3) Central obstruction is way beyond the reasonable for visual work. The scope will be seriously challenged by smaller telescopes with much less central obstruction in that area. If visual work is you main interest, cheaper alternatives are available.
When Roland Christen writes this:
Quote:
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.
I am forced to say that he is completely wrong, if he is talking about a classical cassegrain, as it seems to be the case. A classical Cassegrain (paraboloid primary mirror, hyperboloid secondary mirror) has the same amount of off axis Coma as a Newtonian of similar focal ratio and apperture, regardless of the primary mirror's focal length and secondary mirror's magnification (See Texereau's "How to make a Telescope"). At f/8, this 14" Cassegrain has quite a bit of Coma (that's an understatement), unless one makes use of a 3 Lens Wynne Corrector (Costly), which is also useful to flatten the field. A similar corrector will be necessary on many Ritchey-Chrétiens to flatten the field. And it may be also necessary on the Meade RCXs (complex to explain, let's just say that unless central obstruction is made very high, the Meade RCX will have a curved focal plane).
Digest:
This could be a very good astrograph, but nothing earth shattering, at least optically. I am very suspicious of the Ritchey-Chrétien denomination which seems to be more a marketing ploy than the real thing. I would appreciate to stand corrected: if someone had found a way to mass produce a decent Ritchey-Chrétien that would be great news for glass pushers!
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Vincent
"The universe is a circle whose center is everywhere and the periphery nowhere." Pascal
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geoff
sage
Reged: 11/08/04
Posts: 227
Loc: Cornwall, UK
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Quote:
The primary mirror is laser aligned to the true optical path, then float bonded in place. It is fixed, but literally floats on a layer of adhesive that results in zero stress to the glass and no distortion to the optics (unlike mirror cells or floating point pads). There is no mirror movement
This is quite surprising to me.
In the past, mirror cells were designed to equalise support pressures across the mirror and prevent distortion. Gluing of the optics to a support plate would have been cheaper but was never considered a good solution because equalisation of forces would depend upon a number of factors not under control:
1) Uniform application of the adhesive.
2) Consistent elasticity across the whole bond area.
3) Perfect flatness of mirror surface and support plate, no contamination.
4) Differential thermal expansion of mirror, adhesive and support plate.
I assume Meade have solved these problems.
They claim a bonding agent that is soft enough that the mirror "literally floats" and suffers no stresses but at the same time is stiff enough to maintain the accurate laser alignment that the RC design requires for the life of the telescope. If this is true, then I assume precision mirror cells are a thing of the past.
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Strgazr27
Scope Junkie
Reged: 10/04/04
Posts: 6023
Loc: StonyHill Observatory
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Not to mention they've come up with one heck of an adhesive 
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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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imjeffp
Senior Space Cadet
Reged: 09/30/03
Posts: 4433
Loc: Cedar Park, Texas
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Made by 3M, no doubt.
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Blog
ST80 • AT80EDT/LXD650
ETX-90/DS-2000 • 10" LX200 Classic ("The Quarter-Meter Telescope at the Heritage Park Observatory")
SPC900NC • DMK21AF04 • Digital Rebel XT
  
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c131frdave
Post Laureate
Reged: 01/17/05
Posts: 4373
Loc: Arcanum, Ohio
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Quote:
I ordered the 14" RCX from Anacortes. Delivery will be in March.
I was checking out some of the past stuff and ran across this. Boy, was that off!
So did you wait it out? Are you still buying one? 
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