New insulation- jacket for 140 mm Maksutov
Posted: Mon Nov 28, 2022 2:24 pm
Well, if you're still busy sticking radiator foil behind the radiators of the heating, you might as well replace the old insulation jacket of the OMC140 (UK, from 2000) in one effort. So fresh foil on it.
The old foil had been there for almost 20 years. And there were also a few holes and loose patches, due to varying insights into what accessories had to be put on the telescope over the years. The dew shield was made of double black display cardboard, with a newspaper in between. A good moisturizer. In the years that I used the telescope intensely, there was only one condensation, which was dealt with quickly with a hair dryer.
I cut the dew shield open to size and the newspaper of July 7, 2001 reappeared. It turned out to be a science supplement, so carefully selected at the time.
The new insulation jacket for the telescope willingly folded around the tube and I attached the ends together with one long and wide piece of clear tape. If I wanted it off, it would not be a big problem. The old foil had been stuck with it for almost twenty years, so I have never shown a strong urge to remove it again.
I made the new dew shield from the same material, with protostar adhesive flocking material on the inside. The foil cannot be bent very nicely if the carrier underneath (adhesive flocking material) is so flexible, which is why you see some corners at the end. The stars don't mind.
Everything works as usual. Seeing that is created in the tube itself by turbulent air as a result of strong cooling remains reasonably calm. It stays relatively warm in the tube and cooling is very slow and not turbulent. Even with the intense seeing last night, at a magnification of 200+, I could see the thin diffraction ring around Airy's disc. Although it moved rapidly and kept falling apart, it was much better than without insulation. Without insulation a diffraction ring is almost impossible to find at all. With or without insulation: It's about two points difference on the Pickering scale. See the difference here between rating 4 and 6 : http://www.damianpeach.com/pickering.htm
The performance of an OMC140 is roughly equivalent to a good 10cm ED refractor, albeit with some minor differences. It depends a bit on the taste of the observer which of the two is preferred. Read more on that in the conclusions here: viewtopic.php?t=6650
Attached is a photo
The old foil had been there for almost 20 years. And there were also a few holes and loose patches, due to varying insights into what accessories had to be put on the telescope over the years. The dew shield was made of double black display cardboard, with a newspaper in between. A good moisturizer. In the years that I used the telescope intensely, there was only one condensation, which was dealt with quickly with a hair dryer.
I cut the dew shield open to size and the newspaper of July 7, 2001 reappeared. It turned out to be a science supplement, so carefully selected at the time.
The new insulation jacket for the telescope willingly folded around the tube and I attached the ends together with one long and wide piece of clear tape. If I wanted it off, it would not be a big problem. The old foil had been stuck with it for almost twenty years, so I have never shown a strong urge to remove it again.
I made the new dew shield from the same material, with protostar adhesive flocking material on the inside. The foil cannot be bent very nicely if the carrier underneath (adhesive flocking material) is so flexible, which is why you see some corners at the end. The stars don't mind.
Everything works as usual. Seeing that is created in the tube itself by turbulent air as a result of strong cooling remains reasonably calm. It stays relatively warm in the tube and cooling is very slow and not turbulent. Even with the intense seeing last night, at a magnification of 200+, I could see the thin diffraction ring around Airy's disc. Although it moved rapidly and kept falling apart, it was much better than without insulation. Without insulation a diffraction ring is almost impossible to find at all. With or without insulation: It's about two points difference on the Pickering scale. See the difference here between rating 4 and 6 : http://www.damianpeach.com/pickering.htm
The performance of an OMC140 is roughly equivalent to a good 10cm ED refractor, albeit with some minor differences. It depends a bit on the taste of the observer which of the two is preferred. Read more on that in the conclusions here: viewtopic.php?t=6650
Attached is a photo
