I lost count of my scopes. Now I just want mobility. I came, I saw, I bought some interesting accessories, and put names to faces: NEAF 2012, ASAE 2012, SWAP 2013, ASAE 2013.
Quote:I've asked Roland about this directly- namely since I have been wondering about making a little future-life instruction card to put in with my AP130EDFGT when I am forced by circumstances I would put off indefinitely if it were up to me ultimately result in it being passed on.
The application in all of these is a very thin layer of fluid between lenses with a capillary sized air gap between them. The idea here is to have a material with an index of refraction closer to the glass so large reflections don't appear, even with bold use of high end optical coatings. In a way, this is similar to a cemented lens, but unlike with a cemented lens, if something goes wrong with the intermediate layer, it can be fixed. In practice, these lens sets are difficult to see when mounted as the only reflections are from the very first and very last surface, and those are with ultra-high transmission coatings.
The "Oil" is, in fact, oil. It is a vacuum compatible ultra-low vapor pressure oil chosen for its chemical stability and resistance to evaporation. The oil's primary use is in hard disk drive bearings, which should be the datum to allow someone to find equivalents in the distant future. Failing that, he suggested olive oil, or any clear oil with a similar index of refraction and a general resistance to going rancid.
The oiled lenses are designed to last indefinitely, and my understanding is either AP or TEC fix lens cells showing a bubble at no charge.
So, if you are nervous about getting a scope with oil spaced lenses, I suggest you shouldn't be- the image contrast is simply amazing.
Quote:Hello everyone,I was informed that the "Oil" used in TEC Oil spaced Triplet Refractors has a lifespan longer than the Human Life....The "Oil"was referred to as a "Immersion Liquid".Many Thanks.
“I am the only person to ever ace a 1951 USAF resolution test. My 'to observe' list says 'done'. I do not use charts or atlases when I starhop; men do not use maps. One of my sketches won an SBIG deep sky imaging contest. I am the life of star parties I have never attended. I never say anything looks like a faint fuzzy - not even a faint fuzzy. Pilots aim green laser pointers at me. Don Pensack proofreads my CN forum posts.” - The Most Interesting Astronomer in the Universe
Quote:and my understanding is either AP or TEC fix lens cells showing a bubble at no charge.
Calypte Anza, California
SteveC TEC 140 Intes Micro 715 deluxe TEC 110 SolarMax 40 Losmandy G-11 w/Gemini, CGEM, Vixen Skypod TEC EP Turret, AP Maxbright, Denk P/S Diagonal, Denk II B/V, EarthWin P/S Slide TMB Supermonos, ZAO IIs, Zeiss Monocentrics, Naglers, 24mm Panoptics, 14mm Meade UWA, 5mm Pentax XO, 20mm ES100, and 2.9mm, 4.4mm, 5.9mm, 7.4mm Couture (ball)
Quote:Quote:and my understanding is either AP or TEC fix lens cells showing a bubble at no charge.That's nice. What about after Roland and Yuri have retired? If you're interested, I can share a photo of a brand-new A-P 130GT with a discontinuity in the oil. Not sure I'd call it a "bubble." Roland repaired it, of course, but the risk of something like this happening to a scope several years from now would make me nervous. There's no chance I'll ever get an A-P (I'll be dead before my name bubbles to the top of the list), but I've looked fondly at the TEC 140.
14.5" Starmaster with ServoCat and Argo Navis 1966 Unitron 4" Model 152 EQ Tec 140 TV NP101 f/5.4 APO Telvue .8 Focal Reducer FLI ML8300 and CFW-2-7 filter wheel Astrodon Gen2 RGBL 2" filters Baader 2" Narrow Band Filters Borg 50mm Guide Scope/ATIK Titan Guide Camera AstroPhysics AP900 Losmandy GM-8 Gemini
N11GPS Fastar//TOA-130S//MK66 Std//AT6RC//Vintage C5//Megrez II 80mm APO//SolarMax 40 NJP Temma II//Sirius EQ-G Too Many Astro-Cameras//Mallincam Color Hyper Plus Two not-spoiled Golden Retrievers - Casey and Nelson Lot 19 Deerlick Astronomy Village (Canis Major)
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
Quote:What's up with your preoccupation with TEC building materials?
Planning on going into the scope making biz?
Quote:My 1986 AP oil spaced lens is as good today as the day I bought it. Gerry
Quote: I can share a photo of a brand-new A-P 130GT with a discontinuity in the oil. Not sure I'd call it a "bubble." Roland repaired it, of course, but the risk of something like this happening to a scope several years from now would make me nervous.
The opinions expressed herein are solely mine as an amateur astronomer hobbyist & consumer. Information herein was correlated from experience, discussions with others, & research from multiple sources freely available at time of posting. All reasonable care & skill was used, but no warranty is made as to accuracy, & liability cannot be accepted for errors/omissions. This is for information only and not intended nor implied to be a substitute for professional advice.
Quote:I also currently own two Televue Starbeam Red Dot Finders.
Quote:What happens if the seal between lenses leaks and you get condensation between air-spaced lenses?