5 mm Radian Review

Here is a review of the 5 mm Radian that I found on the TMB website:

http://voltaire.csun.edu/tmb/tmb3.html

Check it out.

I have the 3-4-5-6mm Radians and I agree with this review. I find them to be world class EPs with serious planetary ability and sharpness that makes high magnification a pleasure. I have used the 3mm with the Big Barlow on the Moon several times for 1060x with great images and good contrast and throughput. The Radians when properly adjusted with the Insta-adjust are easy to use and do not have blackout. They will work for eyeglass wearer and those that do not need them. I have not seen any ghosting or internal reflections in any of them.
I also enjoy the Naglers and have a few of those as well.

I hate to say it, but I have not always agreed with the Cloudy Nights reviews. In fact there have been a few times where I thought they were completely off base.
The Radians are a great EP. I have done my own side by side testing and found the to be more than a match for most EPs in the same f/l. Plus, they are a pretty good deal here on Astromart used! I have paid a total of $510 for the four that I have. One I bought from someone local for an extremely good price. That is really an unbeatable bargain in my opinion.

I also own a 5mm Radian and find it extremely good on planets and deep sky alike. Far, far superior to my old 4.8 Nagler (original type) that I used to own. It not only works great on planets in my 8" f/8, but also fantastic on globulars in my 13.1" f/4.5. M13 from a dark site in the 13" with the 5mm is truly a sight to behold.

I also own 14mm and 8mm Radians. When doubled with my 2x TV Barlow I also get the equivalent of 7mm, 4mm, and 2.5mm FLs. They're definitely keepers.

Doug

Richard Orr had some nice things to say about this eyepiece:

http://www.company7.com/library/televue/orrtv5mmN.html

I own a 4mm Radian. I use as a dedicated high-power eyepiece for my Pronto where it delivers 120x.

The Radian is very comfortable to use, and I like the Instajust fixture that keeps out extraneous light.

My only complaint is that this eyepiece tends to show dirt against a bright sky background. Any speck of dust on the eyelens becomes a shadow splotch in the field of view. This results from a narrow exit pupil. It becomes very noticeable if you rotate the eyepiece while observing.

I know that I should just keep my eyepieces clean.

I like the 4mm Radian, but I still enjoy the 82 degree Naglers.