From: "tmboptical" <TMBoptical@...>
Date: Mon Jul 4, 2005 2:34 am
Subject: New BO/TMB Planetary Series Eyepieces

After designing and having a very successful run of my TMB Super Monocentric eyepieces, selling ~3500 before Markus Ludes decided to cancel the product, due to the natural slow down of any new product, that hits critical mass, i.e., a specialized eyepiece of the highest quality, that has a bell shaped selling curve, as the very first buyers will buy it sight unseen, because it is a product they wanted very much. Then the good reviews come in, and you get the maximum sales, and then sales slow, when all the people that wanted this type of eyepiece, all have bought their's. Then sales level off, to a much lower rate, as new people find out about them, or previous owners order more to fill in their focal lengths. Normally that would still be more than enough to keep the product in production, but the Super Mono is a very expensive eyepiece, and has a small field of view (30 degrees), so we don't sell very large numbers anymore. The only way we could continue to keep selling them, would be to raise the price way too high, and what sales we have now, would drop to almost zero. Thus, Markus had to make the decision to stop production. But it was a very good run, and not only did we sell a lot more than I thought we would, the TMB Super Monocentric turned out to be even better in performance, than in my dreams.

Two issues with the super monos were the eye relief, and the small AFOV, although most owners and myself feel that these are not issues -- but nevertheless -- if you can bring out a planetary quality eyepiece, with very high contrast, has a 58 degree field, and 20mm of eye relief, with only 6 elements, using a new super ("Black") multicoating, with super sharp images, and is sharp to the edge of the field, well you would have an eyepiece that almost no one would have issues with. And that is the new eyepieces I have designed.

Working with Bill Burgess (Burgess Optical), Bill was able to have three prototypes made (4mm, 6mm and 9mm) that pass my tests in every eyepiece parameter. This is the first wide angle, long eye relief eyepiece that has the sharpness, contrast, and lack of scatter that the best orthos have, but without the limited eye relief, edge correction, and long eye relief (even down to the 3mm focal length eyepiece) that planetary orthos have.

I have tested the 4mm on Jupiter, and have star tested it against the TMB Super Monos, the Zeiss Abbe orthos, and the TeleVue Radians. The Radian was clearly inferior, while the Zeiss and TMB were better, but only by a very minor amount in scatter - truly amazing. In the sharpness department, the BO/TMB Planetary eyepieces were as good as any eyepiece I have used, equaling the Monos and Zeiss Abbes. Jupiter, even in less than ideal seeing, showed very fine detail in my TMB 152mm f/7.9 apo refractor, that other high quality eyepieces had a harder time showing, if at all.

They have an adjustable eyecup, like the Pentax XL eyepieces, and have enough eye relief for people that need eyeglasses, and for everyone else, you can fine tune the eye relief so the field stop is ideally visible. I think the photo will give you an idea of their size; they are compact, and very binoviewer friendly. The eyelens is very large, and spherical aberration of the exit pupil is under control. No bad blackouts like so many other eyepieces.

Now the part that I am very excited about. They are only $99.00 each. The focal lengths are not all set, but we plan on 2.5mm, 4mm, 6mm, 7.5mm, 9mm, 12mm, and a 17mm or 18mm, depending on if our optical supplier can fit the field lenses in the 1.25" barrel. [updated fl's 07-06-05. ed.] If you feel you would like to see more focal lengths, let us know.

Thomas Back