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Old Thursday 16th May 2019, 06:54   #7
John A Roberts
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Join Date: Aug 2017
Location: Perth
Posts: 159
B) VEILING GLARE
I have the luxury of a long westerly view from my front door, allowing convenient comparison of binoculars
The view slopes down to a river, across a bay, and then to rising ground on the opposite side around 5 km/ 3 miles away
The view also provides extremely harsh viewing conditions in the late afternoon, accentuating the effects of veiling glare

My experiences in relation to veiling glare are in the same order as those of Hermann
I find that under extreme conditions the 8x30 exhibits significant glare, the 10x40 somewhat less, and the 7x42 markedly less
(the 7x42 has a different eyepiece than the other 2 models, and looking through the objective it also has a slightly smaller opening to the internal stop consistent with the narrower Field Of View)

Again under extreme conditions, the 7x42 Traditional shows a little more glare than either my 7x42 Leica Ultravid HD (pre-Plus) or 7x42 Zeiss Victory FL (pre-LotuTec)
- but there is not a significant difference as to the discernible detail in the centre of the FOV

- - - -
I was initially hesitant to get a 7x42 due to it’s narrow FOV (nominally 6.5 degrees, 114 m/ 342 ft) and the supposed ‘porthole’ effect (or perhaps more correctly porthole illusion?)
However, after getting my 8x20 (nominal FOV of 6.5 degrees, 113 m/ 341 ft) in order, and using it for some time, I reconsidered the matter

Although the 7x42 has a slightly smaller AFOV, the perceived image seems much less restricted than that of the 8x20
I suspect this is in part due to the vast difference in the size of the exit pupils (the area of the 7x42’s is nearly 6 times that of the 8x20!)
n.b. the above is so even under optimal conditions for the 8x20 - in bright sunlight where my pupils would have closed down to 2.5 mm or less

Compared to the Leica and Zeiss 7x42’s, the Traditional’s view is as good - it just does not cover as much of the landscape. However, in practice I’ve not found this a great concern
When I’m looking at something in detail, I normally centre it in the FOV - and visually and mentally concentrate on it - making the peripheral view irrelevant


C) FOCUSING
Especially when new, the focuser is distinctly stiff on fogproof Traditional models (i.e. post-1984 production, readily identifiable by the cover screws on the bridge arms)
With a new unit it’s worthwhile to repeatedly cycle the focuser back and forth along it’s full range of travel, as this typically both slightly smooths and lightens the focuser action


PUSH- PULL FOCUSING
The best way to ‘drive’ the focuser when using the binoculars is with a 2 finger push-pull motion, which works ideally with the hold I’ve described above


FOCUSER TRAVEL
As is common with many external focus binoculars, the Traditional has a lot of excess travel past the point where infinity focus first occurs

From what I’ve observed, while the total focuser travel varies slightly with each unit, it is typically:
- between 1 1/4 and 1 3/8 rotations from lock to lock
- with slightly more than 1/2 rotation past the point of infinity focus

So the actual needed rotation for the full focus range is usually less than 1 complete turn (and of course the amount of rotational movement needed also progressively increases as the focus distance decreases)


FOCUS SCALE
The Traditional models have both:
- a focus scale on the focuser, and
- an index mark on the underside of the bridge arm assembly, in the 6 o’clock position
the first photo shows the scale on a current production unit, and the second shows that on a 1962 era unit

When the zero point on the focus scale is set to the index mark on the underside of the bridge, the focuser is at the nominal infinity focus position - see the third photo
In practice with current models, infinity focus is normally achieved with the zero point set to around 5 o’clock


PRE-SETTING THE FOCUS DISTANCE
With any binocular, getting into the habit of setting/ checking the focus when picking it up, enables the avoiding of excess twiddling when one needs to focus quickly
With their harder than usual focuser action, pre-setting the focus works especially well with Traditional binoculars

My preference, depending on the anticipated circumstances is usually one of two settings:

A) Pre-setting the zero point to 3 o’clock, so that the focus is at about 10 metres/ 11 yards
- and so less than 1/4 turn clockwise will take the focus to infinity
- and 1/4 turn anti-clockwise will shift the focus to near the minimum focus distance

B) Pre-setting the zero point to 4 o’clock, so that the focus is at about 20 metres/ 22 yards
with the clockwise and anti-clockwise rotation varying accordingly


John
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Last edited by John A Roberts : Thursday 16th May 2019 at 11:22.
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