Steve, are you at all concerned that the eye relief changes between the two powers - from 18.7 to 21.8mm?
Michael
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Binocular ramblings (1 Viewer)
- Thread starter Tero
- Start date
Michael
Steve C
Well-known member
MacGee
No, I guess I'm really not worried about that. I do not wear glasses when using binoculars, and have not been plauged with eye-relief problems as yet. However it is something I will evaluate, because all of my binoculars are 3.7 or better in exit pupil, while the 12x32 is less than that. If it proves to be a problem, I can either live with it or not I guess. For example there is no problem for me going between the 6x Yosemite and the 8x Yosemite with a 21vs 14 mm ER. If nothing in this search of mine pans out, I'm really OK with what I have.
No, I guess I'm really not worried about that. I do not wear glasses when using binoculars, and have not been plauged with eye-relief problems as yet. However it is something I will evaluate, because all of my binoculars are 3.7 or better in exit pupil, while the 12x32 is less than that. If it proves to be a problem, I can either live with it or not I guess. For example there is no problem for me going between the 6x Yosemite and the 8x Yosemite with a 21vs 14 mm ER. If nothing in this search of mine pans out, I'm really OK with what I have.
FrankD
Well-known member
Arthur,
Wow, this thread really took off since you last posted. My apologies for not replying sooner.
I can definitely see the benefit of how you utilize your two bins and after having read your comments in this regard in the past I have often considered giving a 10x32 a hard look. Heck, after reading some of the Leica 10x25 comments I even considered giving one of them a go. What I realized always holds me back is that I truly get enjoyment from a binocular when I look through it and get an "experience". For that to happen for me I really like wide true and apparent fields of view, bright images and larger exit pupils to let me eyes wander around the image. A few 8x42s and several 7x42s give me that experience. I keep a few 8x32s because they are handy but short of the 8x32 FL (and maybe the 8x32 Trinovid) they don't "move me" like their larger siblings.
Don't get me wrong I can see where the 10x32 would have a strong practical use in the applications you mentioned.
To add to the rest of the discussion, I have to admit that I have some curiousity in the 7/12x32 GR. I think I would be more interested in it if it was a 7/10x32 or possibly a 7/12x42 but 12x with a 32 mm objective? I don't know if I could use a 2.5 mm exit pupil to pull out fine detail. If I only used it occasionally then maybe but then if I only use it occasionally then is it really worth having?
Just thinking out loud.
Alexis Powell
Natural history enthusiast
Just get me the 7x32 and 9x32 and then I am all set. Forever.
Personally, I'm holding out for a 7.8x34 -- now that would be PERFECT!
--AP
Steve C
Well-known member
Tero,
The Swift, with its larger exit pupil seems to me to have an advantage over the 8x32 glasses I have experience with in the dawn and dusk hours. The resolution seems better to me as well. If there is a resolution difference with an 8x such as a Ziess Conquest or even a Minox Hg 8x33 for that matter, I don't see it. I also don't see an image size difference between 7 & 8x either. The 7x view is something I think my own optical system "likes", for lack of a more explanatory term. In short a 7x seems to have, for me anyway, what we see people describing as more relaxed image. The 6.5x32 Fury is much the same for me as the Swift. I'd take either one over any 8x32 of similar optical quality that I have so far had any experience with. Those who wish for a top tier 7x30ish ought to try the Swift.
I will post an update when I try the switch power. You're right, we've really rambled in this thread, so when I do it, I will use a new thread.
Frank, to be honest, I have some 12x misgivings, but IF, the 12x is good enough for my purposes, and IF the 7x is at least the equal (preferably the better) of the Swift I might decide it's worth the $900. If not significantly better than what I have, I'll likely loose interest. I am probably somewhat more iterested in a good full size 7-8x, which about the sole gap in my inventory.
The Swift, with its larger exit pupil seems to me to have an advantage over the 8x32 glasses I have experience with in the dawn and dusk hours. The resolution seems better to me as well. If there is a resolution difference with an 8x such as a Ziess Conquest or even a Minox Hg 8x33 for that matter, I don't see it. I also don't see an image size difference between 7 & 8x either. The 7x view is something I think my own optical system "likes", for lack of a more explanatory term. In short a 7x seems to have, for me anyway, what we see people describing as more relaxed image. The 6.5x32 Fury is much the same for me as the Swift. I'd take either one over any 8x32 of similar optical quality that I have so far had any experience with. Those who wish for a top tier 7x30ish ought to try the Swift.
I will post an update when I try the switch power. You're right, we've really rambled in this thread, so when I do it, I will use a new thread.
Frank, to be honest, I have some 12x misgivings, but IF, the 12x is good enough for my purposes, and IF the 7x is at least the equal (preferably the better) of the Swift I might decide it's worth the $900. If not significantly better than what I have, I'll likely loose interest. I am probably somewhat more iterested in a good full size 7-8x, which about the sole gap in my inventory.
Pinewood
New York correspondent
Hello Frank,
My decision to use two binoculars is akin to the photographer who carries two lenses: an understanding of the limits of one optic and of my own abilities. If I enjoyed using a 10x42, then the other binocular would be something like a 7x32, if it existed. In fact, such a combination would provide more disparate twilight abilities. However, my 10x32 was cutting edge, two years, ago, and probably delivers as much light as a 10x40 of twenty years, ago.
I would suggest that you look through the 10x32FL or another 10x32 HD or EDS glass and decide if it provides an "experience." In matters of contrast and colour, I certainly had an experience.
Happy bird watching,
Arthur :brains:
My decision to use two binoculars is akin to the photographer who carries two lenses: an understanding of the limits of one optic and of my own abilities. If I enjoyed using a 10x42, then the other binocular would be something like a 7x32, if it existed. In fact, such a combination would provide more disparate twilight abilities. However, my 10x32 was cutting edge, two years, ago, and probably delivers as much light as a 10x40 of twenty years, ago.
I would suggest that you look through the 10x32FL or another 10x32 HD or EDS glass and decide if it provides an "experience." In matters of contrast and colour, I certainly had an experience.
Happy bird watching,
Arthur :brains:
Tero
Retired
I have no doubt the 7x will be pretty good. That in itself is worthy of note, there is no other 7x32. But it is really the 12x part we want to hear about.
I would actually pay up to 400 for a decent 7x32, just to see how it looks. Ideally a fov over 400ft, as I always go for the biggest apparent field available in any format. Thus the Excursion 8x28 and not the Fury 8x28.
Steve C
Well-known member
Tero,
The Swift 7x36 Eaglet is $410 at Eagle Optics. Trust me its more than decent. It is also the same size as the typical 32mm family member in spite of its larger objective. The only thing it doesn't have is a 400'+ fov. The 6.5x32 Fury has your big fov @445' and I can see no difference in image size. $299 at Eagle Optics. Not quite as sharp as the Swift but darned, darned close. Also bigger than the Swift. If you don't like the 6.5x just exchange it for the 8x version.
The Swift 7x36 Eaglet is $410 at Eagle Optics. Trust me its more than decent. It is also the same size as the typical 32mm family member in spite of its larger objective. The only thing it doesn't have is a 400'+ fov. The 6.5x32 Fury has your big fov @445' and I can see no difference in image size. $299 at Eagle Optics. Not quite as sharp as the Swift but darned, darned close. Also bigger than the Swift. If you don't like the 6.5x just exchange it for the 8x version.
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Kevin Purcell
Well-known member
Swift 7x36 Eaglet
Field of View 374 ft./1000 yds.
or 7.1 degrees gibing a 49.9 AFOV
Vortex Fury 6.5x32
Field of View 445 ft./1000 yds.
or 8.5 degrees giving a 55.1 AFOV
Only 5 degrees in the AFOV so you won't really notice that. But the real field is rather different.
Still the Eaglet is getting a lot of good press here!
Interesting too that the "preferred" format is a lot cheaper than the others in the same model range.
Swift Eaglet 7x36 Roof Prism Binocular Our Price: $409.95
Swift Eaglet 8x42 Roof Prism Binocular Our Price: $479.95
Swift Eaglet 10x42 Roof Prism Binocular Our Price: $489.95
Obviously we know something they don't.
Here's hoping we see more x6, x6.5 and x7 compact and mid-sized bins in the near future.
Tero
Retired
Frank, I had the Fujinon 10x42, and I did not like it somehow, I thought I would not like it in 8x42 either. I was led to believe the Discoverer and Fujinon were the same.
The Diamondback was very close to what I wanted. But not quite. I have not actually seen the Excursion 8x42, but it may be slightly better in brightness and contrast.
I sort of gave up on 400ft. I have it in a 8x32. So I guess the only issue remaining is that if I EVER get an 8x42, brightness, contrast and sharpness are the main points. If I can also get 350-370ft fov, fine.
The Diamondback was very close to what I wanted. But not quite. I have not actually seen the Excursion 8x42, but it may be slightly better in brightness and contrast.
I sort of gave up on 400ft. I have it in a 8x32. So I guess the only issue remaining is that if I EVER get an 8x42, brightness, contrast and sharpness are the main points. If I can also get 350-370ft fov, fine.
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Kevin Purcell
Well-known member
Tero,
Though I haven't posted these results on the "4 budget bins" thread (lots more to come!) I did twilight test the four bins and the Winchester 8x32 (i.e. a Vanguard VDT-8320) I bought from you.
For others, the Winchester has no phase coating but is fully multi-coated. It's OK with more obvious CA than the other bins. As Tero said: a sort of Sporter class bin or "just acceptable".
I looked at relative brightness of the bins in twilight in solid overcast in Seattle (from sunset to sunset+15 minutes -- 2015 to 2030 on Aug 17). I was sitting in the Thomas Street P-patch and viewed three different targets: blooming flowers in the open; a green watering can in the shadows underneath a raspberry bush; covered dense shrubbery (where the Bewick's Wrens like to hang out).
Leupold Yosemite 6x30
Brighter than the Winchester. Good in the open viewing flowers. OK looking at the watering can. Brighter than the others but still too dark to be usable in the shrubbery.
Celestron Ultima DX 8x32
Darker than the Yosemite. Brighter than the Winchester. About the same as the Diamondback. Good in the open viewing flowers. OK looking at the watering can. Too dark to be usable in the shrubbery.
Vortex Diamondback 8x42
Darker than the Yosemite. Brighter than the Winchester. Good in the open viewing flowers. OK looking at the watering can. Too dark to be usable in the shrubbery.
Winchester 8x32
Brighter than the Hurricane. OK in the open viewing flowers. Usable looking at the watering can. Too dark to be usable in the shrubbery. Fine for use against birds in tree tops (CA isn't that bad).
Vortex Hurricane 8x28
Usable in the open viewing flowers. Just barely OK looking at the watering can. Too dark to be usable in the shrubbery. Stray light was especially noticeable with dark targets and a big angle of overcast "brightness".
So the brightness ranking at twilight was:
1. Leupold Yosemite 6x30
2. Celestron Ultima DX 8x32
2. Vortex Diamondback 8x42
4. Winchester 8x32
5. Vortex Hurricane 8x28
So some observations:
The largest aperture isn't the brightest bin.
This was a bit of a surprise as it was one of the main reasons for getting an 42mm aperture bin for fall and winter use in the Pacific Northwest.
Clearly other factors are more important for these budget bins seems of be most significant seems to be transmission of porros versus Schmidt Pechan roofs i.e. total internal reflection versus reflection off three aluminum surfaces makes a big difference.
http://en.wikipedia.org/wiki/Schmidt-Pechan_prism
To get over this you need dielectric mirror coatings (not at this price point, yet). Silver would be better but not good as TIR or dielectric mirrors.
An aluminum mirror coating has a reflectivity in the range 87% to 93% but you get one reflection of the bottom of the first prism and two reflections off the roof (one for each side to rotate the image) of a Schmidt Pechan prism. So to the total loss from reflection in the prism is the cube of the reflectivity of the coating. So for Al that's from 0.66 to 0.80. That loss in reflection is like having an aperture (area) that fraction smaller. Or a diameter the square root of that (i.e. the square root of the cube of the reflectivity).
So for this range of reflectivities the roof bins are equivalent to porros with objective diameters 0.81 and 0.90 smaller. For a 42mm roof that's equaivalent to a 34mm to 37.8mm porro.
Not far from the results I get.
I conclude ... Porros are brighter!
OK. Nothing new here but it's true, especially at the low end (i.e. for roofs that doesn't use silver or dielectric mirror coatings).
Smaller magnifications work better at twilight.
Not because the the exit pupil is larger -- your eye's pupil is still stopped down to around 2 or 3 mm at this point but because more light is hitting the cones in your fovea to perceive color and detail. Not new but perhaps a different twist.
So perhaps the Diamondback would not be a significant difference for you. You'd have ot spend a lot more and get dielectric mirrors for it to work. And I know you don't like porros. Hmmm.
Food for thought at least.
Though I haven't posted these results on the "4 budget bins" thread (lots more to come!) I did twilight test the four bins and the Winchester 8x32 (i.e. a Vanguard VDT-8320) I bought from you.
For others, the Winchester has no phase coating but is fully multi-coated. It's OK with more obvious CA than the other bins. As Tero said: a sort of Sporter class bin or "just acceptable".
I looked at relative brightness of the bins in twilight in solid overcast in Seattle (from sunset to sunset+15 minutes -- 2015 to 2030 on Aug 17). I was sitting in the Thomas Street P-patch and viewed three different targets: blooming flowers in the open; a green watering can in the shadows underneath a raspberry bush; covered dense shrubbery (where the Bewick's Wrens like to hang out).
Leupold Yosemite 6x30
Brighter than the Winchester. Good in the open viewing flowers. OK looking at the watering can. Brighter than the others but still too dark to be usable in the shrubbery.
Celestron Ultima DX 8x32
Darker than the Yosemite. Brighter than the Winchester. About the same as the Diamondback. Good in the open viewing flowers. OK looking at the watering can. Too dark to be usable in the shrubbery.
Vortex Diamondback 8x42
Darker than the Yosemite. Brighter than the Winchester. Good in the open viewing flowers. OK looking at the watering can. Too dark to be usable in the shrubbery.
Winchester 8x32
Brighter than the Hurricane. OK in the open viewing flowers. Usable looking at the watering can. Too dark to be usable in the shrubbery. Fine for use against birds in tree tops (CA isn't that bad).
Vortex Hurricane 8x28
Usable in the open viewing flowers. Just barely OK looking at the watering can. Too dark to be usable in the shrubbery. Stray light was especially noticeable with dark targets and a big angle of overcast "brightness".
So the brightness ranking at twilight was:
1. Leupold Yosemite 6x30
2. Celestron Ultima DX 8x32
2. Vortex Diamondback 8x42
4. Winchester 8x32
5. Vortex Hurricane 8x28
So some observations:
The largest aperture isn't the brightest bin.
This was a bit of a surprise as it was one of the main reasons for getting an 42mm aperture bin for fall and winter use in the Pacific Northwest.
Clearly other factors are more important for these budget bins seems of be most significant seems to be transmission of porros versus Schmidt Pechan roofs i.e. total internal reflection versus reflection off three aluminum surfaces makes a big difference.
http://en.wikipedia.org/wiki/Schmidt-Pechan_prism
To get over this you need dielectric mirror coatings (not at this price point, yet). Silver would be better but not good as TIR or dielectric mirrors.
An aluminum mirror coating has a reflectivity in the range 87% to 93% but you get one reflection of the bottom of the first prism and two reflections off the roof (one for each side to rotate the image) of a Schmidt Pechan prism. So to the total loss from reflection in the prism is the cube of the reflectivity of the coating. So for Al that's from 0.66 to 0.80. That loss in reflection is like having an aperture (area) that fraction smaller. Or a diameter the square root of that (i.e. the square root of the cube of the reflectivity).
So for this range of reflectivities the roof bins are equivalent to porros with objective diameters 0.81 and 0.90 smaller. For a 42mm roof that's equaivalent to a 34mm to 37.8mm porro.
Not far from the results I get.
I conclude ... Porros are brighter!
OK. Nothing new here but it's true, especially at the low end (i.e. for roofs that doesn't use silver or dielectric mirror coatings).
Smaller magnifications work better at twilight.
Not because the the exit pupil is larger -- your eye's pupil is still stopped down to around 2 or 3 mm at this point but because more light is hitting the cones in your fovea to perceive color and detail. Not new but perhaps a different twist.
So perhaps the Diamondback would not be a significant difference for you. You'd have ot spend a lot more and get dielectric mirrors for it to work. And I know you don't like porros. Hmmm.
Food for thought at least.
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Pinewood
New York correspondent
Hello Kevin,
Very interesting but contrary to the standard method of computing the twilight factor, which is the square root of the multiple of magnification and aperture. It also seems to be contrary to what hunters seem to find.
However, I will write that Twilight Factor may be too simple to describe twilight perception. Zeiss derived this term for users at a much higher latititude, where twilight is more extended than in areas most people inhabit in the continental USA.
As the binoculars you mentioned were three 8x32's and a 6x30, are you referring specifically to the Yosemite?
As for the light output of Porro's vs. roof prism binoculars, it takes a lot of high priced engineering to overcome the inherent faults of the Schmidt-Pechan prisms.
Happy bird watching,
Arthur :scribe:
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Tero
Retired
Kevin, you need to add some more field to the field testing. The twilight test on flowers is fine, but it is actually birds we are normally after. I tried to look for hummingbirds in Seattle, did not find any. There should be more than one species. I had some 8x25 pocket binoculars with me then. There is a marshy shore by the university, down by the University parking lots and a mall. It is a listed wildlife area. I found a Marsh or Sedge wren there. Also a Bewick's Wren on campus. Some shore birds at the marsh. And some insects that bit me. Chiggers? We have them here.
Anyway, with the Small Bird ID test, you will see if the 6x30 Yosemites work for you , or maybe you need 8x30.
Anyway, with the Small Bird ID test, you will see if the 6x30 Yosemites work for you , or maybe you need 8x30.
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