New To Astronomy
Aluminum vs. Carbon Fiber Telescopes
By Vic Maris
Which Tube Should I Choose: Aluminum or Carbon Fiber?
Stellarvue currently offers our 130 mm and 140 mm apo triplet telescopes in either an aluminum or carbon fiber tube and dew shield. Many prefer the "sexy" appearance of the carbon fiber tube, while others like the classic look of the aluminum tube. We get a number of questions from customers wanting to know which is best. This page will help you decide for yourself by giving you the real pros and cons.Cool-Down Time
Aluminum tubes adapt to the night air rapidly. Carbon fiber tubes may retain heat depending on how they are made. Former models that used felt lined interiors cooled much more slowly than our current SVX models that use interior painted carbon fiber. Customers who have purchased both have yet to complain about cool down time but under extreme conditions when temperatures may drop rapidly, the aluminum tube is preferred.Durability
Aluminum tubes are painted or powder-coated, while carbon fiber tubes are plastic coated. Tightening the rings too much on a carbon fiber tube can create marks on the tube. The aluminum tube is technically more durable.Aluminum tubes are threaded to accept aluminum fittings. Carbon fiber tubes have aluminum fittings bonded to them using epoxy. There have been cases where import telescopes on the market have had issues with parts falling off; much of this is due to improper cementing. For this reason, we bond these parts together ourselves using a generous overlap. Our bonding process increases durability and ensures alignment of parts during the process. That being said, threading aluminum fittings to an aluminum tube is a more durable connection.
Solar Work
Our white aluminum tubes do not get as hot outside in daylight as black or graphite-colored tubes. Solar observers prefer white tubes. For only occasional solar work, the color of the tube does not present a major issue.Thermal Expansion/Contraction
Some say they prefer carbon fiber since it does not contract when temperatures drop. They think carbon fiber tubes maintain focus better. What they may not realize is that lenses shorten in focal length as they cool down. This does not mean that aluminum is better in this regard; it only means that you should not select carbon fiber thinking you will never need to adjust focus as the telescope cools down. Both telescopes will require some refocus when the temperature drops.
Weight
At about nine pounds each, there was an insignificant weight difference between our former 102 mm carbon fiber telescopes and our current aluminum tube Raptor telescopes. This and the other advantages of aluminum tubes is what influenced our decision to convert our 102 Raptors to an aluminum tube. There is a larger difference when it comes to our 130mm and 140mm telescopes. For example, the SVX130T-R carbon-fiber telescope weighs 19.8 pounds whereas the SVX130T in aluminum weighs about 21 pounds.The Bottom Line
You should select the tube type based on your personal preference. Carbon fiber tubes cost a little more but may be lighter. Carbon Fiber refractor tubes will not eliminate the need to refocus when it gets cold. Aluminum tubes do cool down faster and they are more durable.
