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7X42 format. (1 Viewer)

Hello,

that is not correct...
http://www.optik-foto-mueller.com/swarovski/Technische_Daten_FG.pdf
The apparent field of vision is 61 degrees...

Andreas

P.S. Sorry, only in German, see "augenseitiges Sehfeld."
A lot of the manufacturers use different methods to compute AFOV. So it becomes hard to compare different binoculars across the board. I use the simplified method of FOV(Degrees)XMagnification=AFOV(Degrees). So the SV 8x32 is 8X8=64 Degrees AFOV and the Nikon 7x42 EDG is 8X7=56 Degrees AFOV.
 
When comparing FOV....is comparing a 42mm platform to 32mm platform an apples to apples comparison? If one wants to do that let's start another topic.... If one wants to compare 7X to 8X then fine...but let's stick to a 42mm platform since there aren't any comparable 7X32s AFAIK...

ALL expressed as feet@1000yds...

7X42 UVHD+ - 420ft
8X42 UVHD+ - 389ft

SLC 7X42 - 420ft
SLC 8X42 - 408ft

Victory FL 7X42 - 450ft
Victory FL 8X42 - 405ft

EDG 7X42 - 420ft
EDG 8X42 - 405ft

Meopta B1 7X42 - 411ft
Meopta B1 8X42 - 402ft

With the type of birding I do from now thru October I feel like a 7X42 may have a slight advantage but I also realize this is completely personal preference. But why in the world would I use a 7X42 when I can walk out the door with a 8X42? OR a 8X32?
 
I use the simplified method of FOV(Degrees)XMagnification=AFOV(Degrees).
Hello Dennis,

This method is extremely inaccurate!
Example Swarovski 12x50, 5.7 degrees FOVx 12 is 68.4 degrees AFOV manufacturer 63 degrees!
I measured the 12x50, (63 degrees) the Swarovski 8,5x42 (60 degrees) and the Zeiss SF (64 degrees), in all measurements the manufacturer's specifications are correct.
The Nikon EDG 7x42 has only 54 degrees!
The manufacturer of some glasses do not perform correct measurement and use the above simple formula is regrettable, but these data are often much too high.
For high-end eyewear, the manufacturer's measurements are usually the same and why should Swarovski at the 12x50 "only" specify 63 degrees for the AFOV if it is according to your formula in reality 68.4 degrees?
Understatement ... why?

Andreas
 
I've never really understood the obsession with AFOV... Isn't true field of view more important when trying to pick up on birds? I know I'd rather have a 7x42 with a 420' field than an 8x42 with a 380' field when scanning for warblers, hawks, etc. I know I can pick up more along the periphery of my view with my 7x UVHD than my lower field specified 8x binoculars.

Justin
 
I've never really understood the obsession with AFOV... Isn't true field of view more important when trying to pick up on birds?

Justin

Hello Justin,

yes, that's right, but there are many people here who want to know something about binoculars, so it is important to at least correctly specify the parameters that are objectively determinable,only that was my point, the difference between 61 degrees and 64 degrees AFOV is significant, and AFOV is for many People no unimportant criterion to buy binoculars.
I like to enjoy a "window view" even if the facial field is smaller compared to another glass, you are just more "in" the binoculars.

Andreas
 
I think most people can deal with 59 degrees AFOV or more in a 8X or more, frankly to fret about 61 or 64 is a waste of ones time. The really nice characteristic of a 7X42 or even a 6X42 is depth of field.

Andy W.
 
I think most people can deal with 59 degrees AFOV or more in a 8X or more, frankly to fret about 61 or 64 is a waste of ones time.

Hi Andy,

... then Zeiss has probably wasted too much time with his SF models ... ???

Andreas
 
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Andreas,

You said that, not me about Zeiss wasting time with the SF, nice glass, I used to own one. Frankly, I presume you have the SF, now go enjoy them. I have plenty of glass and I enjoy them all, I do not get wrapped up with the difference of apparent views from 61 to 64, other things are more important to me.

Andy W.
 
I have used several pairs of 8x42s and one pair of 7x42s. The 7s are now my primary binocular.

There are two advantages that (I think) I notice in the 7s.

1. The increased depth of field means that birds are easier and faster to find in thick trees or bushes. This will occasionally allow me to see and identify a bird when my partner is still searching with her 8s. This could be the technique or it could be differences in makes and models, but I suspect the magnification is a contributing factor.

2. Everyone knows that lower magnification is easier to hold steady, but what does that actually mean when comparing binoculars of such similar magnification? To me, the main difference here is the one-handed usability. I can be carrying my tripod and scope over my shoulder, and quickly bring my 7s up to my eyes with my opposite hand and make an identification. I find that I miss more birds when I try to do the same thing with my 8s. This could be attributed to my perception or to other variables, but here I think that the difference in magnification is most likely.

This is all anecdotal, but I think that I actually identify more individuals with my 7s than I do with my 8s. The 7s are just really fast because of the steadiness and the depth of field. In general, the identifications that I miss are usually because I am not fast enough, and not because I can't see far enough. The 7s are faster, so I make more identifications with them.

Having said that the 8s do offer a noticeable, but small, amount of additional detail when I am looking at a bird that isn't moving very much or is far away.

-as you were, q
 
I'm still getting to know my 7x42's but I know enough to say that 8x is my preferred general use format.
What I like most of all about them is the increased depth of field but I do notice the decreased magnification more than I thought I would so in many instances they feel a bit distant in view.
As far as the extra FOV is concerned it's neither here nor there for me, the UV doesn't have a particularly wide FOV for a 7x42 anyway and where I'm hoping to get more use out of them is in dense vegetation and terrain so the short distances won't really display any FOV advantage however I'm hoping the increased depth of field will. The last time I thought it'd be nice to have them was in hilly, dense terrain observing a colony of Bell Miners where I had my 8x32's with me and they did very well on that note.
I do like the 7x42 format, actually more than I may have expressed, but they are relatively new and I do definitely favour the overall balance of 8x for my taste.
 
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Hello Justin,

yes, that's right, but there are many people here who want to know something about binoculars, so it is important to at least correctly specify the parameters that are objectively determinable,only that was my point, the difference between 61 degrees and 64 degrees AFOV is significant, and AFOV is for many People no unimportant criterion to buy binoculars.
I like to enjoy a "window view" even if the facial field is smaller compared to another glass, you are just more "in" the binoculars.

Andreas

Hello Justin and Andreas,

I have searched this forum and googled the issue and still do not understand the possible practical difference between AFOV vs. true field of view (which I understand is the FOV expressed in meters or feet per 1000) in terms of how AFOV may affect the perceived image or viewing experience as compared to the true FOV. I always get the impression from the explanations that the two are identical, although that obviously cannot be correct on my part because the two are expressed in different numeric values.

If I understand Andreas' last comment above, I too much prefer an image in which the view is surrounded by a narrow circle of black (is this what is meant by "window view"?) as opposed to some binoculars where the black circle nearly equals the radius of the image. But i don't know whether this characteristic or difference is related to AFOV.

I am interested and would be grateful either for an explanation or a reference to a resource that explains the practical difference in use. Apologies if this is an unintelligible question and thanks in advance for any guidance.

Mike
 
Hello Justin and Andreas,

I have searched this forum and googled the issue and still do not understand the possible practical difference between AFOV vs. true field of view (which I understand is the FOV expressed in meters or feet per 1000) in terms of how AFOV may affect the perceived image or viewing experience as compared to the true FOV. I always get the impression from the explanations that the two are identical, although that obviously cannot be correct on my part because the two are expressed in different numeric values.

If I understand Andreas' last comment above, I too much prefer an image in which the view is surrounded by a narrow circle of black (is this what is meant by "window view"?) as opposed to some binoculars where the black circle nearly equals the radius of the image. But i don't know whether this characteristic or difference is related to AFOV.

I am interested and would be grateful either for an explanation or a reference to a resource that explains the practical difference in use. Apologies if this is an unintelligible question and thanks in advance for any guidance.

Mike
http://www.astronomyforum.net/telescope-forum/227352-afov-vs-tfov-eyepiece-explanation-pictures.html
 
I would hedge that in order from most popular to least popular 8X then 10X then 7X. I am sure there are more 7X users who participate or engage on this forum, but for the masses outside of Birdforum, 7X is the least popular.

Andy W.
 
Hello Andy,

In general one can say that many amateur astronomers like to use 7x when it comes to freehand.
My Nikon EDG 7x42 is often used in the sky, and some colleagues use the Fujinon FMT 7x50 in good visibility conditions (high alps).
I particularly like the 7-format, because it can be kept virtually jitter-free. In this point, it is simply preferable to 8x.
I think it's a shame that there are only a few 7x formats, a market certainly exists.
Andreas
 
Hello Justin and Andreas,

I have searched this forum and googled the issue and still do not understand the possible practical difference between AFOV vs. true field of view (which I understand is the FOV expressed in meters or feet per 1000) in terms of how AFOV may affect the perceived image or viewing experience as compared to the true FOV. I always get the impression from the explanations that the two are identical, although that obviously cannot be correct on my part because the two are expressed in different numeric values.

If I understand Andreas' last comment above, I too much prefer an image in which the view is surrounded by a narrow circle of black (is this what is meant by "window view"?) as opposed to some binoculars where the black circle nearly equals the radius of the image. But i don't know whether this characteristic or difference is related to AFOV.

I am interested and would be grateful either for an explanation or a reference to a resource that explains the practical difference in use. Apologies if this is an unintelligible question and thanks in advance for any guidance.

Mike

Hi Mike,

Looking at the windows simply means the maximum possible AFOV.

Unfortunately, my English is not enough to describe complex optical properties of binoculars. Here I just do not have the subtleties of the English language!
I would be afraid to cause confusion here, I would try, so I can not explain complex things.
The link from "[email protected] but should help, I hope it...;)

Andreas
 
I would hedge that in order from most popular to least popular 8X then 10X then 7X. I am sure there are more 7X users who participate or engage on this forum, but for the masses outside of Birdforum, 7X is the least popular.

Andy W.

Hello Andy,

In general one can say that many amateur astronomers like to use 7x when it comes to freehand.
My Nikon EDG 7x42 is often used in the sky, and some colleagues use the Fujinon FMT 7x50 in good visibility conditions (high alps).
I particularly like the 7-format, because it can be kept virtually jitter-free. In this point, it is simply preferable to 8x.
I think it's a shame that there are only a few 7x formats, a market certainly exists.
Andreas

Andy,
I agree with that order and agree with Andreas that it IS a shame that more 7X choices aren't still available. Most folks just are not binocular fanatics as MOST of us are. Most probably have ONE binocular to do everything. Maybe two, something like a full-sized 8X42 and then a compact. That's it. So in their mind they think 8X is the best compromise of FOV and magnification. They purchase their one 8X and they are DONE. I can't say they made a bad decision...certainly it would be a good FINANCIAL decision! LOL!
 
I cannot see where the method used to figure afov matters at all. If one uses the old fashioned way the generally accepted wide angle binocular is typically right at 60*. Introducing tangent computation reduces that to about 55*. Meanwhile the true fov of the binocular remains the same. One can hold to a belief is pure accuracy, and that's fine and good. However magnification times angular fov is a whole lot easier than using tangents in the matter.


Justin,
As for the obsession with afov, what about the obsession with true angular fov? Try looking at a 7x and am 8x with each having an 8* fov. Tell me which looks wider? I think the wider afov is one reason why the 8x format is far more common than the 7x, despite the advantages of 7x, which I do not dispute, being somewhat of a 7x fan myself.

If you think the 7x42 with an 8* field is wide (not making wide angle limits) you better stay away from a 9*+ afov 7x glass. You have to stay with a less than 8* 8x glass when favoring wide views when all your 7x brings to the table is 8*. Again I'n not knocking 7x, I like the magnification a lot. I have over 20 7x binoculars. all over the wide angle afov level. An 8* 7x just makes me yawn as far as a wide angle view goes, even though I find the format wide enough. Too bad that is about top end for a good, modern 7x glass. If you could get a n Ultravid (or comparable) in 9*+, then the whole 7x wide field argument would enter a new dimension.
 
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