Lymax CosmicOne SCT Cooler for 14" Meade or Celestron SCT Telescopes
The CosmicOne SCT Cooler - or "Cat Cooler" - is a device for ventilating the inside of SCTs, Maks, and other catadioptric telescopes so that they may be brought quickly to ambient temperature. This allows image-ruining tube currents and heat pillars to be minimized in 10-20 minutes instead of the usual 45 minutes to 2 hours. The greater the temperature difference between the place your telescope is stored and the outside evening air, the more quality viewing time you can reclaim with a CosmicOne SCT Cooler. The SCT Cooler has a filtered air intake and other design features which minimize the possibility of dust infiltration and direct the air flow away from the internal optical surfaces.
Why SCTs and Maksutovs need ventilation? Catadioptric telescopes - or "cats" - have closed optical tubes. These closed tubes are great for keeping the optics clean, but they also prevent air circulation. This lack of circulation limits conductive heat transfer and greatly prolongs the time required for the optical tube to reach the ambient outdoor temperature. The temperature differential between the telescope and the surrounding air cause "heat pillars" and "tube currents". These tube currents cause distortion similar to the wavering mirages you might see over a road on a hot day. Until the telescope tube and the optics it houses reach a temperature close to that of the surrounding environment (equilibrates), it will not give the best images. In fact, fine details on planets or in deep sky objects may be completely invisible while the scope is changing temperature, but are easily visible when it has reached ambient temperature. Some high quality Maksutov telescopes have built-in fans because their thick front lenses can trap heat for many hours - making them almost unusable without some sort of ventilation. Schmidt-Cassegrain Telescopes (SCT) have thinner Schmidt corrector lenses sealing the front of the tube, but they still suffer from the same effects as the Maksutov design. Very few SCTs have any sort of ventilation system.
How does it work? The CosmicOne SCT Cooler is inserted into the rear cell of the telescope so that it fits snuggly in the 1.25" visual back or in to an SCT to 2" adapter. The end of the Air Delivery Duct projects into the body of the telescope far enough so that it is well clear of the central baffle tube, but not so far that it is a danger to the secondary mirror or inside the secondary baffle.
The CosmicOne SCT Cooler draws outside air in through a high capacity fan. The air passes through a dust filter and into a cone shaped duct. Air passes through the holes in the end of the Air Delivery Duct and shoots towards the sides of the optical tube with a slight backward angle. The swirling outside air mixes with the air in the tube. The positive pressure causes the mixed air to flow back out through the central baffle tube where it is exhausted through grooves in the blower body.
Lymax CosmicOne SCT Cooler Features
- Quickly brings SCT and similar telescopes to ambient temperature.
- Can assist in removing moisture (dew) from inside optical tubes.
- High quality, high output ball-bearing DC fan with polarity and thermal protection.
- Modular construction allows one unit to be used with several telescopes - just change the tube!
- Air Delivery Duct made of durable Nylon based plastic prevents nicks and scrapes.
- Specially designed air ports direct ventilation away from optical surfaces.
- Dust filter helps keep optics clean.
- Machined blower body works with 1.25" visual back or SCT to 2" adapter.
- 10 foot power cord.
- 12V power connector with integral fuse and red LED power indicator.
- Spare filter and allen wrench included.
Lymax Product Number: SCTCR114