Search the Community
Showing results for tags 'doublet'.
Found 4 results
Hi, I'm keen to buy a small good quality refractor primarily for astrophotography of galaxies and nebulae. I'd like to use my Pentax K1 full frame DSLR with the telescope. Reviewing YouTube & Google the; Altair Astro 72 EDF deluxe & William Optics 71GT look like they might be good models to go for. I'd welcome the community's views on both, and any other alternatives people recommend.
Has anyone unglued and reglued an eyepiece doublet? In order to solve some problems that I was having, with a Celestron 4mm Omni Plossl, the eyepiece was dismantled. The scope-side doublet was found to have been misaligned during assembly : I'm guessing that the lenses are superglued together. The method that I'm considering, would be to place the lens, flat(ish) side down, on wood, in a pre-cut delve, probably adding panel pinning for stability ... and place in the oven. Over-cook the lenses, in order that they stay above the bond temperature... Using plastic pincers, and a piece of card ... clamp to wood, and apply the micrometer anvils (or vice versa - probably less risky). Then leave it ... hoping that the bond remakes. I'd be loath to apply liquid superglue, because it is likely to wick through the gap. I need 'gel superglue', to reinforce what I would hope would be auto rebonded lenses. It sounds simple enough, but it's a task that can easily go wrong, and end up with superglue being smeared across the lens faces. This is why I'm thinking that panel pins would be a good idea. Another Risk might be glue vapour. Over-cook yes ... but not enough to vaporise the glue. Anyway, that's one current planning option. Perhaps another method would be to melt the glue in boiling water (if it will melt), and then clean off the lenses with acetone. ... before cold gluing. The other option is to leave the task for the moment, and re-benchmark the eyepiece after completing the various required mods. ... but, it's out, it needs doing, and after a few practice runs, the actual task might be done in under 30 seconds. Either way, the task needs reviewing. If anyone has any prior experience in this area ... I'm all ears
I kinda "force" my Astrotrac with my 102ED on top so I'm out shopping for something more appropriate... an 80 mm FPL53 is a must for both doublet and triplet. It will be used for astrophoto and visual g'n'g. After tons of reviews and articles I came with a very shortlist. And here comes my indecision, since the tubes are more or less "identical" but labeled by different companies. -triplet represented by Orion ED80T CF Astro-Professional APO 80 Carbon TS 80mm f/6 (not Carbon) Tecnosky Triplet FPL-53 APO 80/480 -doublet (more or less alike) made by TS 80/500mm Altair Lightwave 80mm F6.25 The budget is 1000$ (~800e) not a cent extra Altair Lightwave doublet and AstroProfessional triplet are my favorites, but can't decide which. thank you