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Did you run out of boxes, Lurch?
New = Better? (binoculars)
- Thread starter moribundman
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"If you did pay even marginal attention, why do you want me to consider another pair of 7x50 binocs?"
If you're complaining about quality then start with a good brand and see what they have. Fujinon makes an 8x30, which was also tested at the site mentioned above. They also use to make a superb 6x30 but it seems hard to find these days. I've gotten rid of smaller binoculars than those like inverted porros as the exit pupil was just too small for my taste, where I prefer a porro monocular like a 7x30 or 8x30.
If you're complaining about quality then start with a good brand and see what they have. Fujinon makes an 8x30, which was also tested at the site mentioned above. They also use to make a superb 6x30 but it seems hard to find these days. I've gotten rid of smaller binoculars than those like inverted porros as the exit pupil was just too small for my taste, where I prefer a porro monocular like a 7x30 or 8x30.
Originally Posted By: 1sttruck
If you're complaining about quality then start with a good brand and see what they have.
Gee, why didn't he think of that?
Take a look at the image quality column here and the price:
http://www.birds.cornell.edu/Publications/LivingBird/Winter2005/Age_Binos.html
You do, in fact, get what you pay for.
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If you're complaining about quality then start with a good brand and see what they have.
Gee, why didn't he think of that?
Take a look at the image quality column here and the price:
http://www.birds.cornell.edu/Publications/LivingBird/Winter2005/Age_Binos.html
You do, in fact, get what you pay for.
.
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Originally Posted By: 1sttruck
If you're complaining about quality
I am complaining about a drop of quality by comparable binocs with near identical specs from the same manufacturer, who now outsources. That was my complaint.
I don't need 8x30 binocs. I have my 7x50 Steiner binocs, which suffice for all my super high resolution and large exit-pupil needs.
You may not know this, but there is no reason for a large exit pupil for use in bright light, which is exactly when I use compact binoculars. The reason is that your pupils contract in bright light to a very small size. Let's say your binocs have an exit pupil of 7 mm (7x50 --> 50:7= 7.14 exit pupil) and you use those binocs in bright daylight conditions, you cannot make use of the large 7 mm exit pupil, because your pupil will contract to a size smaller than 7 mm. In low light you will need an exit pupil large enough to match your pupils' maximum dilated size, which can be over 7 mm. If you are middle-aged or older, you don't even need a 7 mm exit pupil, because your eyes cannot dilate much beyond 5 mm anymore. That's why you may want to stop driving at night when you get old.
If you're complaining about quality
I am complaining about a drop of quality by comparable binocs with near identical specs from the same manufacturer, who now outsources. That was my complaint.
I don't need 8x30 binocs. I have my 7x50 Steiner binocs, which suffice for all my super high resolution and large exit-pupil needs.
You may not know this, but there is no reason for a large exit pupil for use in bright light, which is exactly when I use compact binoculars. The reason is that your pupils contract in bright light to a very small size. Let's say your binocs have an exit pupil of 7 mm (7x50 --> 50:7= 7.14 exit pupil) and you use those binocs in bright daylight conditions, you cannot make use of the large 7 mm exit pupil, because your pupil will contract to a size smaller than 7 mm. In low light you will need an exit pupil large enough to match your pupils' maximum dilated size, which can be over 7 mm. If you are middle-aged or older, you don't even need a 7 mm exit pupil, because your eyes cannot dilate much beyond 5 mm anymore. That's why you may want to stop driving at night when you get old.
Originally Posted By: moribundman
You may not know this, but there is no reason for a large exit pupil for use in bright light, which is exactly when I use compact binoculars. The reason is that your pupils contract in bright light to a very small size.
Of course, the objective size is nearly irrelevant in bright light as well. The reason is that the additional light gathering of the large objective is wasted since your eye will reduce your pupils to a very small size.
So, if you're buying binoculars for use in the Sahara at noon, you can get by cheap.
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You may not know this, but there is no reason for a large exit pupil for use in bright light, which is exactly when I use compact binoculars. The reason is that your pupils contract in bright light to a very small size.
Of course, the objective size is nearly irrelevant in bright light as well. The reason is that the additional light gathering of the large objective is wasted since your eye will reduce your pupils to a very small size.
So, if you're buying binoculars for use in the Sahara at noon, you can get by cheap.
.
"You may not know this, but there is no reason for a large exit pupil for use in bright light, which is exactly when I use compact binoculars."
A common way to improve optical quality is to stop the system down as it's hard to minimize aberrations over the entire field, espcially at the edges. Per my eyes the differences in optical quality only get more dramatic in bright daylight when comparing a small inverted porro design, any design as a matter of fact, to a larger, higher quality binocular that is being stopped down. I find that I can see more with a monocular than with the typical small binocular.
A common way to improve optical quality is to stop the system down as it's hard to minimize aberrations over the entire field, espcially at the edges. Per my eyes the differences in optical quality only get more dramatic in bright daylight when comparing a small inverted porro design, any design as a matter of fact, to a larger, higher quality binocular that is being stopped down. I find that I can see more with a monocular than with the typical small binocular.
Another consideration is the tolerance of alignmenet between ones pupils and the optical system exit pupil, say trying to align a 3mm pupil in both. In order to get the whole exit pupil the disance between the barrels has to be PERFECTLY aligned and in order to get the whole pupil the binocular then has to be held PERFECTLY in line with the eye. Even half a mm, 0.020 inches, can reduce the exit by almost a third as it's 0.5mm on one side amd 0.5mm on the side, typically with shake in addition to alignment. Typically one provides tolerance in order take advantage of an important attribute, this case being the exit pupil of the optical system.
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1sttruck, you keep completely ignoring the fact that the older Pentax binocs suited my needs and wants for relatively small carry along binocs. Poor alignment is on what I myself have blamed the worse performance of the new Pentax binocs four pages of mostly useless discussion ago. Check again, just in case you missed that.
You yourself suggested 8x30 binocs. Too large for my needs! They don't fit in my jacket pocket without making me walk around lopsided, okay? Besides, 8x30 binocs have an exit pupil which is only marginally larger at 3.6 mm than is the exit pupil of 7x24 binocs. In terms of sheer bulk, I may as well carry my 7x50 binocs. So, unless you know my pocket size and how much weight I am willing to carry, please don't even as much as guess to figure what binocs I should want in your opinion. Don't tell me what I want.
Regarding precise alignment, don't be ridiculous by making 0.5 mm (You found that figure online, didn't you?
) precision/accuracy/tolerance (take your pick) in mounting prisms seem like an almost unachievable goal. The prisms are commonly dropped into very precisely cast (if "plastic" and often also machined if metal) bases where they are held with flat springs. 0.5, or even 0.1 mm inaccuracy is HUGE in an optical system. This brings me to the reason why I do not ever buy roof prism binoculars, in which prism alignment is even more critical than in a porro prism design. An optical device is generally easily knocked out of alignment, so roof prisms are a no-go for me.
In the pictures below you can see in what fashion a typical prism is mounted. The prism drops into a precisely shaped recessed cutout (see red arrow heads in the picture below), where the prism (see green arrow in picture below) is held in place by a flat spring (see pen pointing at it). Alignment beyond this would require the use of shims. I can't measure what clearance the prism has in it's pre-made cutout, but it's a tight fit -- tight enough for the prism to not fall out if the spring is removed.
My point is, exact prism alignment can be and frequently is achieved simply through excellent fit of parts and careful assembly. With modern manufacturing techniques and materials, bungling something like alignment in an optical system requires quite come carelessness and sloppiness.
I'm done with this thread and I will not further comment, because I know the "discussion" of what my wants and needs should be will continue along with the liberal dispersal of snapped up half truths and outright misinformation until the cows come home and then some. Have a go at it, I don't care!
You yourself suggested 8x30 binocs. Too large for my needs! They don't fit in my jacket pocket without making me walk around lopsided, okay? Besides, 8x30 binocs have an exit pupil which is only marginally larger at 3.6 mm than is the exit pupil of 7x24 binocs. In terms of sheer bulk, I may as well carry my 7x50 binocs. So, unless you know my pocket size and how much weight I am willing to carry, please don't even as much as guess to figure what binocs I should want in your opinion. Don't tell me what I want.
Regarding precise alignment, don't be ridiculous by making 0.5 mm (You found that figure online, didn't you?
In the pictures below you can see in what fashion a typical prism is mounted. The prism drops into a precisely shaped recessed cutout (see red arrow heads in the picture below), where the prism (see green arrow in picture below) is held in place by a flat spring (see pen pointing at it). Alignment beyond this would require the use of shims. I can't measure what clearance the prism has in it's pre-made cutout, but it's a tight fit -- tight enough for the prism to not fall out if the spring is removed.
My point is, exact prism alignment can be and frequently is achieved simply through excellent fit of parts and careful assembly. With modern manufacturing techniques and materials, bungling something like alignment in an optical system requires quite come carelessness and sloppiness.
I'm done with this thread and I will not further comment, because I know the "discussion" of what my wants and needs should be will continue along with the liberal dispersal of snapped up half truths and outright misinformation until the cows come home and then some. Have a go at it, I don't care!
"Regarding precise alignment, don't be ridiculous by making 0.5 mm (You found that figure online, didn't you? ) precision/accuracy/tolerance (take your pick) in mounting prisms seem like an almost unachievable goal. The prisms are commonly dropped into very precisely cast..."
???? Alignment as in the distance between the eyepieces, something that one adjusts.
Decaff man, decaff.
???? Alignment as in the distance between the eyepieces, something that one adjusts.
Decaff man, decaff.
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I know I said I wasn't going to reply, but I presumed you were talking about prism alignment, which is critical. Looking back at what you wrote, it appears I skimmed your post (Having not had any interest in a "discussion" to begin with), so I'll take the blame for being a disinterested reader after four page of posts, almost none of which are relevant to my original post.
I now realize you were simply talking about adjusting (not "aligning!") pupillary distance in order to align each of your pupils with each exit pupil. I thought it was rudimentary that people had that skill, even if the exit pupil was relatively small. I guess I was wrong and some folks need to take a Binocular Use 101 course. Yikes.
Over and out.
I now realize you were simply talking about adjusting (not "aligning!") pupillary distance in order to align each of your pupils with each exit pupil. I thought it was rudimentary that people had that skill, even if the exit pupil was relatively small. I guess I was wrong and some folks need to take a Binocular Use 101 course. Yikes.
Over and out.
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