Denk 14mm eyepieces

[jeelan (Jeelan)]

I got a pair of Denk 14mm eyepieces from Russ Lederman and Denkmeier optical yesterday.

When I opened the package I noticed on the bolt cases, each one has a sticker with a manual value of 15.3mm written on it...

When I queried this Denkmeier, I got a response saying they optically match their eyepieces to within 1/100mm etc etc, but no firm explanation on how a 14mm eyepieces ends up at 15.3mm...

anyone else have this????

I used the eyepieces for a couple of hours in my Lunt 100mm binoculars and they're certainly impressive..

I'm just a bit irritated that this difference in focal length doesnt seem to be advertised anywhere on their website and is a bit misleading....

just venting....

cheers
Jeelan

[ausastronomer (John Bambury)]

If you drift timed all of your eyepieces you will find that most if not all have a slightly different focal length to the stated focal length, irrespective of manufacturer. Similarly if you take 5 mirrors of a stated focal length (say 15"/f4.5) from the same mirror maker unless they are specified as required as a pair, they will all differ slightly somewhere between f4.4 and f4.6, depending on the mirror maker. My 14"/f4.5 Zambuto mirror is actually f4.43. Does it matter? Not 1 iota. Of course optics for the professional and research market are another matter and another price point.

Denkmeier are doing you a big favour by matching them and stating an accurate focal length.

Cheers
John B

[jeelan (Jeelan)]

Thanks John, wasn't sure if this was prevalent among other eyepieces or not...

I'm also in a quandry as to what other eyepiece to get.

I have a pair of XW 10mm and while they are usable in the binos, physically they are simply not as comfortable as the Denk. That's been apparent to me over the 4hrs I spent last night using the Denks...

This is NOT a quality issue, I guess I simply dont have the facial structure to comfortably use them in a binocular...

As such, I'm considering 11mm or 9mm Delites - any thoughts? From what I understand, they are physically almost identical to the Denks so should be equally comfortable..

AS I have some "conventional" binoculars, I'm probably not going to go any longer in the eyepieces - the Denks will be the highest, however I'd like one more pair at shorter focal length..

A lot of people who use Doctor's have said they are pretty much permanently in the binos so while Doctors are NOT an option for me, I'm wondering if that sweet spot for magnification for the 100mm binoculars is that 10mm - 12.5mm range....

if that's the case, the Televue Delite 11mm is perfect, or perhaps the Pentax XF??

cheers
Jeelan