Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

UTHC... is it worth it?

This topic has been archived. This means that you cannot reply to this topic.
9 replies to this topic

#1 Psa19one

Psa19one

    Apollo

  • *****
  • topic starter
  • Posts: 1,098
  • Joined: 12 Sep 2004

Posted 27 November 2005 - 02:44 PM

I have the LX200 Classic (12"). Do the newer UHTC coatings really make much of a difference?

#2 Teal'c

Teal'c

    Indeed

  • *****
  • Posts: 4,367
  • Joined: 02 Aug 2005

Posted 27 November 2005 - 02:51 PM

That question has been brought up about the Celestron XLT also. Some say yes and some say no.

#3 snorkler

snorkler

    Aperture Aficionado

  • *****
  • Posts: 11,582
  • Joined: 11 Oct 2004

Posted 27 November 2005 - 03:53 PM

I've read somewhere it's about a 7% improvement per mirror surface - probably barely discernable. It seems to be as much marketing hype as useful. Most people get it for resale value, but its lack is probably not a deal-breaker.

#4 JerryWise

JerryWise

    Cosmos

  • *****
  • Posts: 9,699
  • Joined: 26 Dec 2003

Posted 27 November 2005 - 04:10 PM

Darrell, 5 days till retirement? Awwww.. Mannn.

Kevin, I agree with the other folks. Sometimes I think the XLT coatings actually add a glare on planetary. As in Mars for the last month. But when I'm in the market for a particular OTA I won't consider one without the premium coatings. It's too hard to resell a non premium coated OTA.

In reading some of Darrell's post I wanted a Meade SN series OTA to look at. Ordered a 6 inch with UHTC and then the Meade EBAY store came out with a 10 inch non UHTC. I jumped all over it for the price. Haven't had a chance to do indepth work with it yet but it looks like a strong performer.

#5 gnabgib

gnabgib

    Viking 1

  • *****
  • Posts: 611
  • Joined: 05 Jun 2005

Posted 01 December 2005 - 12:24 AM

Do the math!
Normal alum/sio coating is approx 88% reflective.
.88 X .88 = 77% thru.
The average UHTC coating is approx 96% reflective.
.96 X .96 = 92% thru.
Two UHTC coated surfaces have 15% more thruput than two alum/sio coated surfaces!

Since we all tend to use our various cassegrain telescopes WITH a star diagonal the numbers are more interesting!
alum/sio .88 X .88 X .88 = 68% thru.
UHTC .96 X .96 X .96 = 88% thru.
Three UHTC coated surfaces have 20% more thruput than alum/sio coated surfaces.
A 20% gain in the objects brightness is very noticable!
Time to get off this soapbox for now.
Clear and steady skies to all
Kevin

#6 sixela

sixela

    Hubble

  • *****
  • Posts: 15,261
  • Joined: 23 Dec 2004

Posted 01 December 2005 - 04:29 AM

A 20% gain in the objects brightness is very noticable [sic] !


I'm not disputing it's enough to change the threshold of detectability on some objects, but saying it's "very noticeable" is a bit of a stretch...

#7 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----

Posted 01 December 2005 - 04:52 AM

Multi-coatings can also degrade performance on fine detail. It's really six of one and half a dozen of another. For strictly deep sky, UHTC might be worth it. HOWEVER, it does not increase detail. For about the price of UHTC you can move up from a standard SN-8 to a standard SN-10. You will get more than the UHTC light gain and an increase in resolving power to boot.......and several pounds weight and more shake on the mount. So it's still six of one and half a dozen of another. Light gain is a lot like SPL gain in audio. Twice the amp power gives you only 3 dB SPL gain. You need 5X that much again to get 10 dB SPL gain to actually sound twice as loud. Light is a lot the same way. Turn on a lamp in a room that is dark. Big change. Turn on another lamp of the same light output and it's not nearly as big a change, and not even close to twice as bright in a perceived sense. I remember when power amps were sold on peak power output, and audio newbies took the bait, and they still do. Power into difficult low impedance highly reactive loads is what you want, with vanishingly low distortion up to the clip point, and under a steady state heavy current draw and not just a short pulse. An amp test performed into an 8-ohm resistor is NOT a test at all in judging how an amp will perform into a real 8-ohm loudspeaker with a crossover network containing coils and capacitors. It tells you how the amp would perform if you decided to use it for a space heater through a resistor. A 2 uF capacitor, which might be 1% the size of a capacitor in an actual crossover network has brought many an audio amp to its knees in actual tests. However, you can literally arc weld out of one channel of some premium amps while playing music out of the other channel. Any audiophile knows you look at efficiency in your loudspeaker before buying a huge amp if you want to listen to music at high sound pressure level. Freedom from light scatter or reflections and preserving high contrast and fine detail has to be attained before raw light gain does you much good. In audio that would be the signal to noise ratio. Your quiets have to be really quiet before your louds really have their startling impact. That is a signal to noise power ratio of a billion to one to even be considered a high end amp (with both signals measured simultaneously and other frequencies mixed in as well), and if my audio amp achieved those figures, it would be considered broke as it is rated at least ten times better than that. It has that quality similar to high contrast in optics that audiophiles call "jump factor" and such. It also costs like an APO refractor, unfortunately.

So sometimes it comes down to small things making more difference than the big things, like how well was the tube baffled and do you have a lens hood in place. I don't think my SN-8 OTA is baffled and blackened well enough for UHTC to make a noticeable difference. I could spend 1/10 the price on flocking cloth and probably get a bigger performance increase as far a increased contrast is concerned. It's a black & white world under the stars, and contrast is everything. Freedom from lightening of the shadows is actually a bigger concern than darkening of the bright areas on most objects viewed. A very small fraction of 1% of the brightest areas leaked into dark areas could ruin detail there as it could be several times brighter than the total light in the dark area. Brandon says no to multi-coating on their EP's, and they are known for high contrast. I would get the UHTC coatings mainly for protection in a highly corrosive atmosphere more than anything else, if I needed that. Too many people have looked at UHTC coatings under the stars and been very slightly impressed in favor or perhaps felt they were slightly inferior in order for it to weigh very heavily for visual observations. They are not even offered on Meade's new Lightbridge Dobs.

If you lived near a salt air environment, I think UHTC would be well worth it, or for resale value if the market dictates that preference. For a cheap scope I intended to beat up by hauling out to observing sites, I wasn't about to pay $125 more on a $500 OTA for something I had to strain to see. The numbers from Meade's ads (and that's all they are if you can't see a notable difference) don't seem to mesh with what observers are telling us they actually saw in comparison. Bose did some highly deceptive advertising in the past that misled some people who followed their rhetoric instead of asking the precise question that the ads deftly sidestepped. Their numbers were correct. The truth was that it didn't matter because the speaker in question was sealed inside the box and you listened to the sound at the reflex port.....which had quite a bit of distortion. That is called designing for specification rather than designing for perceived effect. The numbers didn't lie, they just didn't address the more pertinent issues. I would be more impressed if Meade talked about contrast measurements at the eyepiece, where it counts.

#8 BluewaterObserva

BluewaterObserva

    Fly Me to the Moon

  • ***--
  • Posts: 5,809
  • Joined: 18 May 2004

Posted 01 December 2005 - 10:27 AM

For resale, or really if your buying new you may as well get it.


But used or good deals on OTA without it, I'd jump on them in a heart beat.


Dozens of times I have been in the presence of same sized LX200's same night same observing field with and without, and I don't think even one time even one person claimed to see any difference on any objects.

Just more FYI on it than anything. I certainly see no reason to swap a 12" Classic without, for a 12" GPS with them, that's for sure. I'd consider that change a waste of money.

#9 Guest_**DONOTDELETE**_*

Guest_**DONOTDELETE**_*
  • -----

Posted 01 December 2005 - 04:00 PM

I think Bluewater hit the nail on the head.......use the perceived value of UHTC to save a hunk of money on an OTA without UHTC. It's sort of like bass guitars where some guys pay a big premium for neck-thru construction over bolt-on construction. A neck-thru rings like a piano a bit more, but the bolt-on is a bit punchier. Six of one and a half dozen of the other. The wood in the neck and body makes more difference, and the pickup makes more difference than that, which can be changed out rather cheaply. UHTC may be like the "magic wire" craze that had a lot of audiophiles spending big bucks on cable for rebadged generic Belden cable and such. I use Magami Neglex to make my own interconnects, at about $1.00 per foot. The most used interconnect in recording and broadcast studios around the world. If you think 6' of "magic wire" will remove any residual traces of distortion after having run through hundreds of feet of Mogami Neglex at the studio, then go for it buddy. It's your wallet. Similar analogies exist in astronomy as well.

After having owned five bass guitars, I sold my most expensive ones, a Fender and a Rickenbacker. Bass icons of the rock world. Solid maple construction, premium varnish finish, etc. My Spector made in Czechoslovakia blows both away in build quality, quality of woods, and tonal range. The body is premium alder, which is much cheaper than maple, but the tonal range is about the widest you can get in a tonewood. The Chinese OLP bass, which is the second best of the five and only $229 street price new, has the easiest playing neck of any of the five, and it's a 100% Canadian Rock Maple neck to boot. Of course, for around $1500 you can have the very flashy Rickenbacker in Jetglo varnish with a thin 1-piece flatsawn neck that just happens to want to bend too much around the heel and ruins any chance of a very low action. The $400 Spector (used price) has a 3-piece maple neck with graphite reinforcements and an active Aguilar preamp. The tung oil finished neck of the Spector and OLP is much cheaper, easier to refinish, and lets your hand slide much more smoothly up and down the neck. A situation where less equals more in reality. The 4004 Rick in Jetglo and chrome is a thing of dazzling beauty, but the Spector just flatly outplays it, and I won't even talk about that Fender P-bass hunk of junk. The Spector was built in a Czech factory that has a reputation for building high quality stringed instruments that goes back several centuries. Owners favorably compare them to German Warwick basses that sell for much more.

I have wasted and seen other people waste so much money in their hobbies that I just have to say, "Show me the big difference you're talking about". About 90% of the time, it just isn't there.

I just replaced my Hafler audiophile AM/FM receiver with a Grundig Yacht Boy YB300PE that I got on sale at Radio Shack for around $50. I plugged in stereo headphones and discovered the FM stereo was really good. Besides being small enough to carry in your pocket, running on only 3 AA cells, and able to take out to an observing site, it also receives shortwave bands, which the Hafler did not.

Since Celestron is dropping the Ultima and Axiom eyepiece series, I would expect that Synta/Celestron has a new value priced "premium" EP line coming down the line. I'm holding off on getting any Panoptics and Radians just yet.

The smart move is to see how little you can spend to get what you need. Amateur astronomy is long overdue the big increase in performance for money that other industries have been giving for years. The fact is that most of the work can now be done by automated machinery and cheap Asian labor where hand labor is needed. The new coil pack for my Ford F-150 had "made in China" stamped on it, as did some OEM filters I bought for a Mercedes-Benz from an M-B dealer (I actually found better Austrian filters for a lower price from an M-B parts importer in Houston).

I am typing this using my new LCD color monitor that I paid $219 for at retail that actually outperforms most LCD monitors that sold for $600 a few years ago. Can you allow yourself to pay less and realize you didn't give up one bit of quality? The truth is, you usually DON'T get what you pay for unless you shop around rather aggressively.

Speaking of coatings, remember when auto dealers charged new car customers $300 to $600 for extra undercoating? You could go to a parts store and spend 10% or less on a few cans of spray-on undercoating just like they used and get the exact same thing. Not to diss Ziebart that actually drilled holes in panels and gave new cars a really serious anti-rust treatment. The entire auto industry was eventually forced to build cars with halfway decent anti-rust coatings as standard issue. The moral is to buy based on the pertinent facts, not the fluff (manufacturers choose THEIR facts for ad purposes which may or may not be pertinent). If UHTC is really all it's cracked up to be, then Meade had better make it standard in order to keep up with competition in high end scopes. Tacoma builds acoustic guitars in the USA that are just as good as Martin (if not better), for about half the price. They became the 4th largest USA acoustic guitar builder almost overnight, and their designer was a retired Martin employee. No doubt the positive changes he had in mind were not allowed at Martin because Martin wanted to keep their classic design and not upset longtime fans. Rickenbacker also follows that philosophy, which allows them to outfit Beatles and Byrds cover bands all over the world. Which is OK in a way. The downside is that it stops further progress.

I got longwinded, and this is off the original subject of the thread, but I feel this may not be a good time to make any expensive purchase in astronomical gear (for me at least). Prices will continue to fall and/or technological changes will obsolete what you just bought. I'm going to make any new major purchases in the used market, and not the new market, just like I found works best in musical and audiophile gear. I didn't get hurt much on my Rickenbacker, as I bought it used and they sell fast on the used market, but the P-bass was another story. Amateur astronomy is about where consumer audio was in the 70's. It's a time of huge growth in a field that was very, very niche oriented but is now going much more mainstream as prices fall. That creates further innovation and further price reductions to fuel the fires of change.

Let "astro nervosa" supply you with value priced used gear just like "audio nervosa" does in the audiophile world. I found out that smart audiophiles were paying practically nothing and some were making money by buying only used gear and trading up through the years. Conrad-Johnson solid state was a line that quickly depreciated on the used market, but gave jaw-dropping performance when inserted into your system, sounding almost like the finest tubed components. I think the Burgess TMB planetary EP's may be a similar product and serious competition to Radians. Amateur astronomy was such a niche market that very little of a used market existed. The internet and the recent growth spurt is changing all that, just like it did for quality audio gear in its "golden age" of the 70's, and it's recent growth spurt in the 90's. Suddenly there were guys all over the place with used audio gear and the new market went flat and then dropped precipituously. Some predicted the death of high end audio. Some audio manufacturers just re-engineered and sold a better product for less money. The same is coming for amateur astronomy. Rapid growth is chaotic and not to be feared. Just position yourself to take advantage of it rather than getting trampled by it.

As always, YMMV

Phil

#10 BluewaterObserva

BluewaterObserva

    Fly Me to the Moon

  • ***--
  • Posts: 5,809
  • Joined: 18 May 2004

Posted 01 December 2005 - 05:13 PM

DuckView / Phil is more cynical about it than I am. :)

Every little bit does help, no doubt about it. But a truly great deal on a non ultra coated Meade is better to me than a decent deal on one with it.


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics