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Retrovid 7X35 a viable birding binocular? (1 Viewer)

John A Roberts

Well-known member
Australia
Hi Mike,

It's something Leica does a lot e.g. see my recent comment about the figures provided for the Noctivids:

. . .
This is a common error in Field Of View conversion:

a) There’s 3.3 feet (39.4 inches) to 1 meter. So when converting a length in feet to meters, or vice versa, one divides or multiplies accordingly

b) However, Field of View is a ratio i.e. the width of the field at a given distance
The FOV is the same regardless of the units used, whether:
  • meters at 1000 meters, or
  • yards at 1000 yards

So when converting the width in yards, to the width in feet, there's 3 feet to a yard

The 10x42 Noctivid's FOV is: 112 m at 1000 m > 112 yd at 1000 yd > 336 ft at 1000 yd

- - - -

In the specification table that you attached, to convert the FOV in meters to feet, the conversion factors are:
  • 3.28 for the 8x42, and
  • 3.36 for the 10x42
So who knows what was going on?
. . .

Maybe the work experience kid does the calculations?


John
 

chill6x6

Well-known member
John

Thanks for the useful info and pictures. One question, is it my lack of math skills or is Leica's spec sheet listing the FoV of all three models incorrectly in terms of feet as opposed to meters? E.G. given the 7x35 at 8 degrees and 140m at 1000m, isn't 420 feet at 1000 yards the correct figure rather than 460 feet? The figures listed for the 8x and 10x in feet appear incorrect as well?

Mike
That's correct. I believe they started doing that with the Noctivid. For some reason it doesn't seem to bother Leica that it's incorrect.
 

chill6x6

Well-known member
Thanks for sharing your experiences with the Trinnie Classic.
To what extent would you consider the 7x35 to be pocketable?
It would take a big pocket! Although it's a little smaller than a EL 8X32 it's still not small by other 32mm standards. It's about the same size as a CL B 8X30 which still isn't really a pocket binocular IMO. The previous generation CL 8X30 is pretty close to a pocket binocular...about the largest I'd consider for a "pocket." I tried to make several different 8X30s a "pocket-binocular." Still a "pocket binocular" is a 8X25 dual-hinge model. That's truly a pocket binocular.
 

Sterngucker

RⒶdneck
United States
It would take a big pocket! Although it's a little smaller than a EL 8X32 it's still not small by other 32mm standards. It's about the same size as a CL B 8X30 which still isn't really a pocket binocular IMO. The previous generation CL 8X30 is pretty close to a pocket binocular...about the largest I'd consider for a "pocket." I tried to make several different 8X30s a "pocket-binocular." Still a "pocket binocular" is a 8X25 dual-hinge model. That's truly a pocket binocular.
Thanks for answering my question. I was afraid you'd be saying something like that. Guess I am just trying to kill too many birds with one stone: ≥ 4 mm exit pupil, pocketable, European brand, ≤ 8x (rugged and waterproof too, if at all possible) - in short, my swiss army knife of binos.
 

pbjosh

missing the neotropics
Switzerland
Regarding pocketable... I agree it depends a lot on the pocket. In winter, with a coat on, I think that the 8x30 MHG or CL-B would fit in the pocket of a good percentage of mens' coats. My MHG fits in the hand pocket of all my various winter coats. They don't fit in summer but in summer I am less encumbered and it's not too much work to grab them in and out of a small bag if need be, so I make do. I personally don't like the double hinge bins, and the otherwise excellent Victory 8x25 isn't REALLY pocketable in MY summer pockets, so I've never felt it was a necessary addition, even though I really like it.
 

yarrellii

Well-known member
Regarding pocketable... I agree it depends a lot on the pocket. In winter, with a coat on, I think that the 8x30 MHG or CL-B would fit in the pocket of a good percentage of mens' coats. My MHG fits in the hand pocket of all my various winter coats.
Lately I've been using my 8x30 Monarch 7 without a strap, simply snug inside the pocket of my parka. Whenever I need it, I slide it out (this is doable because of the lack of strap, with the strap on it would not be feasible).
I also do it with the 8x32 ELSV, but is less convenient, and I've done it with the binoculars in question a couple of times, but in this case the lack of armour was a source of concern, not only because the exposed metal parts could get scratched, but due to the risk of a sudden fall (should the binocular slip between my fingers). So I'd say "pocketable" is quite a long shot for the 7x35 Retrovid. However, as Chuck has said, they are really incredible small for a 7x35, smaller than many 8x32.
 

Sterngucker

RⒶdneck
United States
Thanks for all your input. Here in South Texas it is usually t-shirt, shorts (with cargo pockets) or (cargo) pants. Long-sleeved shirt and M65 or jeans jacket in winter. Real coats only for trips north of the Mason-Dixon line, which I try to avoid as much as possible.
Oh, and a goretex rainjacket - cos Stevie Ray Vaughan is so right - Texas Flood.

So bottom line = either some poxy 8x25 with its little eyecups and small exit pupil, or no "pocketability".

But I do not want to hijack the thread - so long.
 
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