eitanaltman said:
Just curious if anyone out there is using TV Naglers with their Pentax scope, and what results they are getting? They have a slightly wider field than the Pentax XW series, but less eye relief (and some astro guys think eye placement is a little more unforgiving as well).
Anyone using these? Do they function well as a birding eyepiece with Pentax scopes?
I tried a couple some time back don't remember exactly what size. They
were not mine and I just messed about with them for a few hours or so.
As I remember them they were awful for terrestrial wildlife observation.
A great deal of field distortion, very slow with a VERY critical sweet
spot and, strangely, TOO wide a field.
This is not to fault them for their intended use which is for astro
observation but for wildlife a big NO. HINT: A star does not move quite
as fast in your FOV as a Chickadee does at 100 feet with your scope at 40x.
70 degrees is about all the normal eye can take in without moving your
eyes or head and doing so really slows things up- a no no when trying
to keep up with fast moving wildlife. There is a good reason that many
high quality eps limit their FOV to 70 degrees or less. In fact you
could make a good case that it's really easier and faster to get a bird
into your FOV with a 65 degree rather than an 82 degree FOV
given the optical limitations of the ultra wides.
Given these limitations and that a 82 degree FOV is really out of scale
to what the human eye can accommodate stay away from them for wildlife
observation.
If you must try TV give the Panoptics a try-much better suited to a
birder's needs.
SF
