Viewing the moon to gauge stability with/without the Forehead Rest when using 8x42 NL's. (1 Viewer)

[Owlbarred]

Old news for some, perhaps, but viewing the moon proved a surprisingly revealing way for making the simple comparisons below.

Conditions: Last evening, an hour after sunset. Moon phase Waxing Gibbous, 84% illumination.

Replicated five times for each of the following:
1. with the Forehead Rest (FR) attached and:
a). both the FR and eyecups comfortably touching my face (for me, eyecup position 4 of 6).
b) eyecups fully retracted (Position 0) with only the FR rest for support,
2. without the FR attached, with the eyecups comfortably touching my face.

Referenced to the numbered categories above:
Each time, when set to 1a, a discernible positive difference in stability was observed.
Stability in 1b) and 2) were not discernibly different, surprising given that with 1b) the binoculars were supported only by the FR.

Note: Arm fatigue from holding the binoculars upward toward the moon for even a short period negated perceived FR benefits.

Edited: the only reason to compare stability with fully retracted eyecups (1b) is that this confers the widest possible field of view when not wearing glasses

 

[Maljunulo]

It does seem that three points of contact would be more stable than fewer.

It‘s nice to have that fundamental principle confirmed experimentally.

Perhaps that’s why there are no two-legged stools.

 

[PW42]

 

[Stuarts vision]

.View attachment 1540186

 

[Maljunulo]

All you have to do is bring a wall with you.

 

[Stuarts vision]

All you have to do is bring a wall with you.

 

[Maljunulo]

Show me a photo of an unsupported two-legged stool standing in the middle of a room.

 

[Swedpat]

Old news for some, perhaps, but viewing the moon proved a surprisingly revealing way for making the simple comparisons below.

Conditions: Last evening, an hour after sunset. Moon phase Waxing Gibbous, 84% illumination.

Replicated five times for each of the following:
1. with the Forehead Rest (FR) attached and:
a). both the FR and eyecups comfortably touching my face (for me, eyecup position 4 of 6).
b) eyecups fully retracted (Position 0) with only the FR rest for support,
2. without the FR attached, with the eyecups comfortably touching my face.

Referenced to the numbered categories above:
Each time, when set to 1a, a discernible positive difference in stability was observed.
Stability in 1b) and 2) were not discernibly different, surprising given that with 1b) the binoculars were supported only by the FR.

Note: Arm fatigue from holding the binoculars upward toward the moon for even a short period negated perceived FR benefits.

Edited: the only reason to compare stability with fully retracted eyecups (1b) is that this confers the widest possible field of view when not wearing glasses

Thanks for confirming the advantage of the forehead rest.
But the eye relief and useful eye relief is great with NL Pure 8x42. I get full field of view even with eyeglasses, and without eyeglasses the eyecups a few steps raised.

 

[Owlbarred]

You're welcome.

Since I don't wear eyeglasses, I appreciated your noting that you get a full FOV while wearing eyeglasses.
Perhaps that is a reason for our differing results -- I don't know.

For me, on those occasions where I now solely use the Forehead Rest for support with eyecups fully retracted (and thus not even touching my face), the FOV is noticeably increased, something I certainly didn't know (nor expect) until Tehri's helpful posts (see post 2,4 in the thread below):

Forehead Rest - unsatisfactory range of adjustment for 8x42s
Excerpt:

The panoramic vision, the 'cinematic' landscape offered by these binoculars with the eyecups in position 0, still amazes me every day after a year and a half of use !
I was just mentioning that I use NL's a lot in this way, but not only, and I'm not saying that it's the 'best' way, all the time, but just trying to answer your question, your concern, 'the eyecups won't contact my face '.

He also provided good advice in sentence 2.

 

[Stuarts vision]

Show me a photo of an unsupported two-legged stool standing in the middle of a room.

 

[Maljunulo]

It’s not in a room.

 

[Stuarts vision]

It’s not in a room.

I give up. Let's get back on thread. Kind regards 👍

 

[Swedpat]

You're welcome.

Since I don't wear eyeglasses, I appreciated your noting that you get a full FOV while wearing eyeglasses.
Perhaps that is a reason for our differing results -- I don't know.

For me, on those occasions where I now solely use the Forehead Rest for support with eyecups fully retracted (and thus not even touching my face), the FOV is noticeably increased, something I certainly didn't know (nor expect) until Tehri's helpful posts (see post 2,4 in the thread below):

Forehead Rest - unsatisfactory range of adjustment for 8x42s
Excerpt:

He also provided good advice in sentence 2.

I don't really understand that. If you see the entire open image and the edges, you see the entire field of view...🤔
I cannot investigate what you mean because I sold my 8x42. But will try to find out if I get one in my hand again.

 

[Owlbarred]

Thanks for the comment. Wish I could help. I've done my best to explain.

 

[William Lewis]

 

[Stuarts vision]

View attachment 1540314

😀😀😀😀

 

[Owlbarred]

I don't really understand that. If you see the entire open image and the edges, you see the entire field of view...🤔
I cannot investigate what you mean because I sold my 8x42. But will try to find out if I get one in my hand again.

Here's a quick easy way to demonstrate this. Put your binoculars on a stable platform with the eyecups fully extended (Position 0). Put a lens cover on one objective lens. While looking through the other (uncovered) objective lens, rotate the eyepiece inward and observe how the FOV increases.

 

[Maljunulo]

That only changes what you see.

User cannot change the FOV of a binocular.

 

[Owlbarred]

That only changes what you see.

User cannot change the FOV of a binocular.

Thank you, sir.

Try the following (from post #17, term FOV changed to "the view widens"), and then report back on what you observe -- your reply is appreciated for clarity. Thanks again.

Here's a quick easy way to demonstrate this. Put your binoculars on a stable platform with the eyecups fully extended (Position 6). Put a lens cover on one objective lens. While looking through the other (uncovered) objective lens, rotate the eyepiece inward and observe how the view widens.

 

[Maljunulo]

Thank you, sir.

Try the following (from post #17, term FOV changed to "the view widens"), and then report back on what you observe -- your reply is appreciated for clarity. Thanks again.

The statement stands, because it is correct.

Words, especially technical terms, have precise and defined meanings.