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View Full Version here: : recommend me a barlow


badabing82
23-05-2011, 12:06 AM
Hi All,

With my impending delivery of an eq6 mount i'm in the hunt for a new barlow.
Will mostly be used in a 8inch f/6 newt for planetary imaging i currently have a 2x gso achro barlow that i bought on a whim so i have that base covered for now but i will upgrade that as i feel the quality is some what average especially visually it dims the image :question:
So in general what should i be looking for ?going to a 2.5x or 3x as i believe the 5x power mate would most likely be over kill and my skies might let me only use it once a year =o)

Waxing_Gibbous
23-05-2011, 04:35 AM
Either a TV 2X barlow, Celestron Ultima Barlow (2X) or TV 2.5X Powermate should be fine. All three are very good optically and decently priced.
I'm not a huge fan of Barlows as they effectively double the FL of your scope and do dim the image somewhat, but they're jolly useful for imaging.

Shiraz
23-05-2011, 09:45 AM
I tried a variety of Barlows when setting up a fairly similar imaging system. The best I found is the 1.25inch TV 3x, which can be used up to about 5x with extenders (it's close to perfect optically). The other two Barlows that turned out to be good quality are a TV 2 inch 2x which is great for lunar imaging (low scattering) and a 2 inch GSO ED 2x which I use for collimation and to improve cheap eyepiece performance. Two other 1.25 inch Chinese Barlows that I bought along the way have been turned into moderately expensive extender tubes. Regards Ray