Sky and Telescope
coated 4mm Orthoscopic
with an approximate 35 degree field of view.
Having been involved in this hobby, off and on, for nearly fifteen, years, and
I've looked through my share of eyepieces. Like many, age and disposable income have allowed me to build a collection of very nice premium eyepieces.
Still, I am a firm believer that many telescopes and eyepieces are better than
most observers, and there is no substitute for knowing how to use your equipment well. I also like value. Money solves many issues, but value is a
rare find. Often, we pay a high premium for that last 5% of performance that
more-often-than-not will make little difference, even on those exceptionally
rare perfect nights.
So it was with value in mind that I purchased the little Ortho. It arrived
unscathed on a clear and steady night with Jupiter and Saturn high in the sky.
It was a week day, so I pulled out the Pronto and went to work. Well, the first thing I notice is that the eyepiece would not come to focus in the
Pronto. I solved this by replacing the Televue 2" - 1/14" adapter with a lower
profile model. Mechanics solved and scope cooled down, I focused on Jupiter.
Most nights the Pronto will yield the N&SEB on Jupiter easily, but with little
detail resolved. I had used the scope two nights before and obtained exactly
those results with my 4MM Radian at 120X.
Placing my eye to the Ortho, I noted the none existent eye relief (your eye is
right-up against this baby) and focused. Well low and behold, tonight I was
seeing four bands on the big planet and a hint of detail in the equatorial
zones. Contrast was also very strong. Could it be that this eyepiece offered
equal or better performance than by $230 Radian? I quickly went inside and
pulled out the premium eyepiece. Allowing my eyes to adjust, I took a last
look through the Ortho and then swapped eyepieces. The Radians larger field of
view and eye relief were welcomed, but the view and detail was no better than
the Ortho. Swapping back and forth I could not reach any firm conclusion, but
for some reason I preferred the Ortho's view.
On to Saturn, and it became apparent that the UO eyepiece was indeed throwing
up a view that was slightly sharper and more contrasty. The Cassini division
was evident, as was the planets shadow on the rings and even shading detail in
the planet itself. These were also present in the Radian, but with a slight
softness and some loss of contrast. The difference was almost imperceptible,
but I think it was there nonetheless.
I am going to keep this little eyepiece and maybe order a 6MM. To be fair the
Radian offers a more comfortable view with a wider field, but in terms of shear
performance, it was a dead heat with favor going to the Ortho. There is alot
of value here. For planetary views the 40 degree field of the Ortho is of little concern, especially if your using a mount that tracks. If you can deal
with the short eye relief, this is a fantastic eyepiece in terms of sharpness
and contrast. I can't wait to try this in my larger scopes, but I'm glad I
used the Pronto. Its was delivering exceptional views of the big gas giants on
this night, and really showed what a small scope can do. While optically no
slouch, its not an APO, so my experience should be readily reproducible with a
modestly priced, larger achromat.
Submitted by Anthony Valvo