Jump to content


Photo

Are Televue EPs water proof?

  • Please log in to reply
48 replies to this topic

#26 Jim Romanski

Jim Romanski

    Vanguard

  • *****
  • Posts: 2256
  • Joined: 02 Jan 2005
  • Loc: Guilford, Connecticut

Posted 17 February 2013 - 02:43 PM

Right, and if TV had introduced N2 purged eyepieces first, they would have been hailed as the greatest thing since sliced bread.



This. And other companies following the good example would be blamed for copying, lack of ingenuity (because they didn't do it first) and generally be laughed upon, because they didn't offer N2 purged waterproof eyepieces before TeleVue.

This is pure speculation and a bit presumptuous. Perhaps some vocal critics will feel this way but I would welcome inert gas purging if Televue decided to offer it. It’s just not high on my list of astronomical eyepiece qualities though.

I surely don't see it as a sales gimmick. It's a genuinely useful feature in some situations and certain climes, for others, it's not an important thing, just as with so many other design parameters. Some are important to you, others not. Choose what you need.


It is a useful feature so I too would not call it a gimmick. That said ES has chosen to market and highlight this as an important feature…just look at their advertising.

Very clever on their part, clone your competitor’s eyepiece yet offer a useful feature that they don’t offer. Market it heavily on that feature and even make sure that the outside of the eyepiece mentions the feature. If you look at binoculars nitrogen purging isn’t often a feature for astronomical binoculars but it is for high quality birding/terrestrial type binoculars. These are binoculars that are used in all kinds of weather conditions including rain. Most of the times the feature will be mentioned in the description of the binoculars but they don’t usually advertise it on the outside of the instrument. That’s the difference between a company like ES and say Zeiss who nitrogen purges many of their binoculars.

#27 Jeff Morgan

Jeff Morgan

    Fly Me to the Moon

  • *****
  • Posts: 5760
  • Joined: 28 Sep 2003
  • Loc: Prescott, AZ

Posted 17 February 2013 - 03:04 PM

There are probably advantages to sealed eyepieces for astronomy though they are not of earth shattering value.


Indeed, for that Amazon star party I was planning in 2026.

But for today, building for lighter weight would be far, far more useful. Swapping 2+ pound eyepieces in and out the focuser can be problematic for the owners of small and medium scopes.

#28 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11879
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 17 February 2013 - 05:05 PM

That’s the difference between a company like ES and say Zeiss who nitrogen purges many of their binoculars.


I would not agree. Each company "chooses" to advertise on their wares what they feel is important to make their product distinctive in marketing. Zeiss plainly writes "T*" on the outside of many of their binoculars to advertise that they are multicoated with their patented process, which they feel makes them distinctive. Personally I find it a problem that Zeiss buries so deeply whether or not their binoculars are Nitrogen filled or not. So a weakness since this is a critical consideration for some of us with binoculars given the harsh conditions we put them through. So IMO Zeiss is not doing anything altruistic by not advertising as prominently their use of nitrogen in "some" of their binoculars since they do advertise other things on them. You have to admit though that nitrogen filling binoculars is quite a common thing so also a reason not to waste valuable product surface space with advertising this. Actually, I find it quite an advantage if vendors listed all the vital specs of a product on a label on them as I'm not apt to keep the box or the literature. So for me, it is an advantage when an eyepiece lists its coating types, glass types, sealing, gas fills, focal length, AFOV, ER as these are important stats about the product. Imagine an eyepiece lot listing the coating level it uses...after a few years out of production will be a common question people ask. So in the end, I think it is a positive move for the consumer to list on the eyepiece if it is special gas filled, etc. Wish my XWs listed their JIS and ER rating on them with the SMC and FL listings they currently carry.

#29 faackanders2

faackanders2

    Vanguard

  • -----
  • Posts: 2349
  • Joined: 28 Mar 2011

Posted 17 February 2013 - 05:16 PM

No. That was ES marketing.

#30 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11879
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 17 February 2013 - 11:14 PM

No. That was ES marketing.


Don't understand the response. :shrug: Point for me is that the "marketing" a company does IMO is immaterial to the product really. Marketing just makes things clearer or less clear and *all* companies (TV, Zeiss, ES, Celestron, Meade, etc.) both fail and succeed at their marketing in different ways. In the end, all the marketing tells one is what the marketing departments are thinking...which is generally quite a bit different from what the engineering departments are thinking...and of course both are a world apart from what the consumers are trying to find out :lol:

#31 jrbarnett

jrbarnett

    Eyepiece Hooligan

  • *****
  • Posts: 20490
  • Joined: 28 Feb 2006
  • Loc: Petaluma, CA

Posted 18 February 2013 - 11:40 AM

Why? Planning on leaving 'em out in the rain or using them as fish tank ornaments between sessions? :grin:

I can see if you were using your eyepieces in spotting scopes in mist and dew how waterproofing might matter. For astronomical eyepieces, though, I don't think waterproofing has much value.

Regards,

Jim

#32 saptharishi

saptharishi

    Mariner 2

  • -----
  • Posts: 205
  • Joined: 15 Jun 2012
  • Loc: Bangalore, India

Posted 18 February 2013 - 02:41 PM

Jim, I should have given a little background info rather than posting a message in Facebook style :)

Wanted to buy a 30-40mm EP. I currently have 17, 10, 6mm ethos and only these three EPs. My natural choice is 31mm Nagler. But then I saw ES having a similar one at half the price and also claimed waterproof. I am such a fan of TV eye pieces, that I was wondering, if TV has not done it then there is something fishy about it :) :tonofbricks:

I really liked the idea of using EP as fish tank ornament :roflmao: BTW, how did you know that I have an aquarium :)

#33 Joe Bergeron

Joe Bergeron

    Vendor - Space Art

  • -----
  • Vendors
  • Posts: 1632
  • Joined: 10 Nov 2003
  • Loc: Upstate NY

Posted 18 February 2013 - 08:47 PM

Yeah. The primary advantage of eyepiece waterproofing is that it allows ES to differentiate their products from the competing eyepieces they copied.

#34 rockethead26

rockethead26

    Gemini

  • *****
  • Posts: 3419
  • Joined: 21 Oct 2009
  • Loc: Arizona, USA

Posted 18 February 2013 - 09:41 PM

Yeah. The primary advantage of eyepiece waterproofing is that it allows ES to differentiate their products from the competing eyepieces they copied.


This debate has happened way too many times on this forum. It has become tiring.

#35 faackanders2

faackanders2

    Vanguard

  • -----
  • Posts: 2349
  • Joined: 28 Mar 2011

Posted 18 February 2013 - 09:57 PM

The only real advantage is to prevent internal fogging.


Another advantage to waterproofing is when you drop your eyepiece into water. The waterproof one will not be ruined.


That's happened many times to me while out observing. No, wait... ;)

I can see it being very important for spotting scopes, I use my Leica in the rain, carry it through swamps, etc. On the astro side I observe in an area that has horrible dew problems and have never had moisture inside a non-waterproof eyepiece.


I observe in heavy dew/ice, and never had an issue with eyepieces yet; but my 25x100 binos did get dew on the inside of one objective :bawling:, and it took me a month with flower drying pellets to get the dew out :question:. Count me as a waterproof believer. :bow:

#36 faackanders2

faackanders2

    Vanguard

  • -----
  • Posts: 2349
  • Joined: 28 Mar 2011

Posted 18 February 2013 - 10:09 PM

My question has always been are the others waterproof. If so for how long. I think this is more of a gimmick. Don' t want no eyepieces that have been dunked in a tank first.

Dereck


Right, and if TV had introduced N2 purged eyepieces first, they would have been hailed as the greatest thing since sliced bread.


Humm...

The reality is that many of the things that TeleVue introduced have been the "greatest thing since sliced bread." The Naglers transformed the eyepiece world and it was not long before Meade had copied them. Likewise with the TeleVue Widefields which were the predecessors to the Panoptic line. The Ethos line was soon copied. For the Newtonian owner, the Paracorr has transformed the what is possible. F/4 and now F/3 Newtonians could not exist they way they do without the Paracorr.

The reason those inexpensive and quite good Explore Scientific eyepieces exist is because TeleVue led the way. Meade and Explore Scientific certainly seemed to think the TeleVue innovations were the "greatest things since sliced bread."

There are probably advantages to sealed eyepieces for astronomy though they are not of earth shattering value. If the telescope one is using is waterproof and sealed, sealed eyepiece are highly desirable but even the Pentax eyepieces designed with spotting scopes in mind are more on the splash proof side. And too, if you look on the binocular forum they will point out that in the long run, unless one is using metal to metal seals like they do in the high vacuum systms, diffusion of the gases through the seals means they do not offer the protection one thinks they do...

Jon


Who was the first to announce/put out 20mm 100 AFOV, 25mm 100 AFOV, 9mm 120 AFOV, and soon 3" 30mm 100 AFOV (and hopfully 3" 40m 100 AFOV, 50mm 82 AFOV, 60mm 70 AFOV)

#37 faackanders2

faackanders2

    Vanguard

  • -----
  • Posts: 2349
  • Joined: 28 Mar 2011

Posted 18 February 2013 - 10:14 PM

No. That was ES marketing.


Don't understand the response. :shrug: Point for me is that the "marketing" a company does IMO is immaterial to the product really. Marketing just makes things clearer or less clear and *all* companies (TV, Zeiss, ES, Celestron, Meade, etc.) both fail and succeed at their marketing in different ways. In the end, all the marketing tells one is what the marketing departments are thinking...which is generally quite a bit different from what the engineering departments are thinking...and of course both are a world apart from what the consumers are trying to find out :lol:


Marketing sometimes is differenterating your product from others. What makes you stick out from the others.

#38 csrlice12

csrlice12

    Voyager 1

  • *****
  • Posts: 11229
  • Joined: 22 May 2012
  • Loc: Denver, CO

Posted 19 February 2013 - 08:43 AM

"Marketing sometimes is differenterating your product from others. What makes you stick out from the others."

In astronomy, Marketing is that time period between the time you hit the "send" button and the arrival of the eyepiece.....apparently, we LOVE marketing.........

#39 johnnyha

johnnyha

    Fly Me to the Moon

  • *****
  • Posts: 6500
  • Joined: 12 Nov 2006
  • Loc: Sherman Oaks, CA

Posted 19 February 2013 - 10:55 AM

My natural choice is 31mm angler. But then I saw ES having a similar one at half the price and also claimed waterproof. I am such a fan of TV eye pieces, that I was wondering, if TV has not done it then there is something fishy about it


There is certainly something "fishy" about a 31mm Angler! :roflmao:

#40 saptharishi

saptharishi

    Mariner 2

  • -----
  • Posts: 205
  • Joined: 15 Jun 2012
  • Loc: Bangalore, India

Posted 19 February 2013 - 12:58 PM

:lol: iPad and its auto-correction!!!! I corrected it :)

#41 csrlice12

csrlice12

    Voyager 1

  • *****
  • Posts: 11229
  • Joined: 22 May 2012
  • Loc: Denver, CO

Posted 19 February 2013 - 01:02 PM

I donno, a fishing pole and a telescope, sounds like two hobbies I could combine pretty easily, gotta have something to do waiting for the sun to go down......

"Give a man a fish, and he will eat today; teach a man to fish, and he'll spend the whole summer in a boat drinking beer......"

#42 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 23160
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 19 February 2013 - 03:35 PM

With semi-permeable seals, Nitrogen-filled will stay Nitrogen-filled a lot longer than Argon-filled will stay Argon-filled. The partial pressure of gases inside and outside the chamber will assure a faster leak rate with Argon.
But even seals that do not keep out a mixing of gases over time may keep out water vapor, and that is the salient reason for the seals in the first place.

#43 bremms

bremms

    Mercury-Atlas

  • *****
  • Posts: 2706
  • Joined: 31 Aug 2012
  • Loc: SC

Posted 19 February 2013 - 04:36 PM

You are correct Don. That is a very good explanation. Best thing is using a desiccant canister in the EP box. keeps them in a dry atmosphere.

#44 turtle86

turtle86

    Pooh-Bah Everywhere Else

  • *****
  • Posts: 3034
  • Joined: 09 Oct 2006

Posted 19 February 2013 - 04:53 PM

You are correct Don. That is a very good explanation. Best thing is using a desiccant canister in the EP box. keeps them in a dry atmosphere.


That's what I do. Plus, I use only one eyepiece at a time and put on a dew heater strap the moment I see any fogging. The eyepieces I'm not using stay in the eyepiece case in the back of my Honda Element. It's usually pretty humid here in Florida, but I've never had any problems with my Televue eyepieces. I do think the waterproofing done by ES is a nice feature and sure wouldn't mind seeing Televue (or anyone else for that matter) follow suit. But in actual practice, the lack of waterproofing isn't that big a deal IMHO for astronomical use and not a factor that by itself would influence my purchasing decisions.

#45 BillP

BillP

    Voyager 1

  • *****
  • Posts: 11879
  • Joined: 26 Nov 2006
  • Loc: Vienna, VA

Posted 19 February 2013 - 05:35 PM

With semi-permeable seals, Nitrogen-filled will stay Nitrogen-filled a lot longer than Argon-filled will stay Argon-filled.


According to this response from Argonne National labratory scientist, molecule size is about the same between the two and neither has propensity to leak more than the other.

Link

Given how simple the construction of an eyepiece is, with no internal moving parts to the optics, I am not seeing why one would expect the seals to deteriorate to the point that they would leak out? Anyone have any actual research tests that confirm that simple constructed devices can't maintain a nitrogen fill for many many years/decades?

#46 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 23160
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 19 February 2013 - 06:37 PM

It isn't molecule size, Bill, it's the difference in partial pressure on one side versus the other.

With Nitrogen, the gas is 100% on one side, 78% on the other.
With Argon, the gas is 100% on one side and 0.934% on the other.
With equal sized molecules, Argon will leak faster due to that factor.

Seals can be quite elaborate, but are usually made from rubber or a polymer of some sort. And the seals can last for many years.

But the leak around the seals is inevitable. Slow, as long as one side is not pressurized higher than the other, but inevitable.

Not a bad idea, though we've had several hundred years of eyepieces so far and most have not been sealed.

#47 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 44341
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 19 February 2013 - 10:39 PM

But the leak around the seals is inevitable. Slow, as long as one side is not pressurized higher than the other, but inevitable.



I think it is diffusion through the seal. Bicycle tubes are an extreme example. High pressure differential, large surface area, relatively small enclosed volume... a 700c-23 pumped to 120psi might be down to 100-110 psi in a week.

Jon

#48 Starman1

Starman1

    Vendor (EyepiecesEtc.com)

  • *****
  • Vendors
  • Posts: 23160
  • Joined: 23 Jun 2003
  • Loc: Los Angeles

Posted 20 February 2013 - 12:03 AM


But the leak around the seals is inevitable. Slow, as long as one side is not pressurized higher than the other, but inevitable.



I think it is diffusion through the seal. Bicycle tubes are an extreme example. High pressure differential, large surface area, relatively small enclosed volume... a 700c-23 pumped to 120psi might be down to 100-110 psi in a week.

Jon


??
Don't know what kind of tubes you use, but 120psi bicycle tires are down to 75-90psi in 24 hours. < 50psi in a week. I'm not riding several hours a day now as I was when I was racing, but when I did train hours per day, we used to air up the tires again after 12 hours because they had gotten soft.

In an eyepiece, though, the pressure is the same on both sides of the seal, so diffusion should be very very slow.

#49 Jon Isaacs

Jon Isaacs

    ISS

  • *****
  • Posts: 44341
  • Joined: 16 Jun 2004
  • Loc: San Diego and Boulevard, CA

Posted 20 February 2013 - 07:37 AM

??
Don't know what kind of tubes you use, but 120psi bicycle tires are down to 75-90psi in 24 hours. < 50psi in a week. I'm not riding several hours a day now as I was when I was racing, but when I did train hours per day, we used to air up the tires again after 12 hours because they had gotten soft.



Don:

I suspect you were either using sew-ups or lightweight latex tubes. I never used Latex tubes but do have some disk and track wheels with tubular tires and they loose pressure quickly.

I commuted on a daily basis for more than 20 years using standard butyl tubes. Most of the bikes were setup with 23's but I also rode 20's sometimes and 25's, I pumped my tires at least once a week and they were never under 100psi unless there was a leak. At 220lbs riding a 700C x 23, any 23mm tire down to under 80lbs was a guaranteed snake bite.

Jon






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics