anj026
27-10-2010, 12:53 PM
Last year I purchased a secondhand Jaegers 6 inch f5 refractor that became available here in Perth. The telescope was usable but a bit rough around the edges and the price was right. It has taken me some time but I've now got it to a stage where it is much easier to use and I am having a lot of fun with it.
I made a new mounting based on the design by Richard Berry in his book on Telescope Making. It is a simple dob style mount using teflon and formica and 19mm plywood (Australian Hoop Pine marine ply). I made the tube rings using a mdf template and a router. I then sanded the insides so that the fit was very tight over the ota when the tube rings are lined with felt. I have also painted the tube green, fitted a 2 speed GSO focuser with a modified drawtube to reduce vignetting and a Rigel finder.
I'm using a wooden pier that was originally from another project that failed. It is great for viewing standing but I am thinking of making it shorter for seated viewing. These alt/az mountings work really well and are not too hard to make with a little patience. The biggest downside is the need for counterweights but that is a minor thing.
The best thing about this type of scope is the great wide field views for scanning the milky way. A 31mm Nagler will show a field of just over 3 degrees at about 25x mag. There is some field curvature as with any short focal length doublet but the contrast is excellent. A 17mm Nagler is about 45x and great for closer looks. I've tried a 13mm Nagler for 59x but this seems to be pushing it a bit too far and the images are not as satisfying. So for higher powers I find it better to use a different scope.
Recently my resistance broke down and I ordered a 21mm Ethos. Bintel used unfair tactics and lowered the price.:D
So far I've only been using the scope from the backyard here in suburbia and I really need to get it to a darker sky. Hopefully this will happen soon.
The blue scope is the before picture.
I made a new mounting based on the design by Richard Berry in his book on Telescope Making. It is a simple dob style mount using teflon and formica and 19mm plywood (Australian Hoop Pine marine ply). I made the tube rings using a mdf template and a router. I then sanded the insides so that the fit was very tight over the ota when the tube rings are lined with felt. I have also painted the tube green, fitted a 2 speed GSO focuser with a modified drawtube to reduce vignetting and a Rigel finder.
I'm using a wooden pier that was originally from another project that failed. It is great for viewing standing but I am thinking of making it shorter for seated viewing. These alt/az mountings work really well and are not too hard to make with a little patience. The biggest downside is the need for counterweights but that is a minor thing.
The best thing about this type of scope is the great wide field views for scanning the milky way. A 31mm Nagler will show a field of just over 3 degrees at about 25x mag. There is some field curvature as with any short focal length doublet but the contrast is excellent. A 17mm Nagler is about 45x and great for closer looks. I've tried a 13mm Nagler for 59x but this seems to be pushing it a bit too far and the images are not as satisfying. So for higher powers I find it better to use a different scope.
Recently my resistance broke down and I ordered a 21mm Ethos. Bintel used unfair tactics and lowered the price.:D
So far I've only been using the scope from the backyard here in suburbia and I really need to get it to a darker sky. Hopefully this will happen soon.
The blue scope is the before picture.