[APSmith]

I know this is a ridiculous title, and doesn't necessarily match the following, but:

ONLY considering the following three criteria, what's the best view?

1. Sweet spot/FOV size (overall field -not just % of view).

2. Ease of view: i.e. no blackouts, easy eye placement, shake friendly, etc.

3. Stray light control.

For the sake of this survey, I'm assuming good resolution and throwing out weatherproofness, weight, handling, eye relief,etc. From all I've read (mostly here), and from personal experience, the glasses to consider for the best combination of these three criteria might include: Nikon EII 8x30, Swaro 8.5x42 EL, Swaro SLC 7x42 (New).

What others should be included on short list?

Thanks, APS

[Tero]

I have not handled high end 8x32s, but I think the 8x32 Meopta would be in the running.

[Kevin Purcell]

Nikon EII 8x30? Not the Nikon SE 8x32? Perhaps that might loose on blackouts (it seems to be a person by person difference).

I've been watching warblers recently (with 7x and 8x bins) and I think I can see why some use 10x even though I've prefered low magnification. As I've seen Townsend Warblers on my local trip to the park the past few days perhaps tomorrow I'll try my 10x each with 6.5 degree FOV (EO Raptor 10x42 porro and Bushnell Excursion 10x42 roof). So perhaps a 10x versions of those mentioned might be on the list.

I'm curious though. Why the edge to edge field requirement? I ID warblers by putting them in the center of the field. But the big FOV is good to follow the flitting so you can get the glimpse of the patterns to do the ID. Are you planning to follow them around the field with your eye?

[ceasar]

The 3 criteria you list are important but I think another one should also be considered.

Depth of Field.

That is, the amount of the view that is in sharp focus in front of and behind the subject you are focused on or trying to get a good look at. Lower power binoculars, in general, have greater depth of field than higher power binoculars.

A binocular that has a lot of Depth of Field comes in real handy when looking into trees and brush, especially if the bird's distance is inside 50 feet or so.

Add this factor, and I think, of the three binoculars you have listed that the SLC 7 x 42 would be your best Warbler glass. 7 x 42's excel in this respect.

Cordially,
Bob

[APSmith]

Thanks for the responses:

(Tero)I think the 8x32 Meopta would be in the running

I'm interested in these.

Originally Posted by Kevin Purcell

Nikon EII 8x30? Not the Nikon SE 8x32? Perhaps that might loose on blackouts (it seems to be a person by person difference).

SE might lose on blackouts. Also, EII has 37% more FOV.

Originally Posted by Kevin Purcell

I've been watching warblers recently (with 7x and 8x bins) and I think I can see why some use 10x even though I've prefered low magnification. As I've seen Townsend Warblers on my local trip to the park the past few days perhaps tomorrow I'll try my 10x each with 6.5 degree FOV (EO Raptor 10x42 porro and Bushnell Excursion 10x42 roof). So perhaps a 10x versions of those mentioned might be on the list.

Quoting myself from an old thread on 10x:

The problem though is this: (as others have also said) I just can't get comfortable with 10X. Considering most of my observation is woodland and backyard birds,etc., the effort required to get and remain focussed is too distracting. It seems (perhaps as you are saying), that at I at least question the diopter setting alot. The strange thing to me is, it seems that the finickiness and frustration (compared to 8x) is greater than the proportion of the power 10/8. The result is, by the time I have adequately adjusted to a new bird, or new position of the same bird, the moment has vanished.

Now, I have been thinking that, in a few fleeting 10X moments, the image was just so good that I needed to have a 10x for regular use. Those few moments were of very cooperative targets, and they were just moments. Yes, they obviously were memorable. But, the question for me is: when/where will I prefer to close the car door and go into the field with the 10X over the 8X? And the answer: Not in any of the field environments that I personally frequent - despite the fact that I may miss getting a noticeably superior view in some particular instant. In other words, I may never really use 10x if I had them. [Of course, I'll probably change my mind if I begin to watch more long range targets, or ones that move less, which I assume most 10x fans are doing(?).]

(I do acknowledge that watching the feeder, or waterfowl, or generally slower moving single targets, etc that higher power becomes more desirable.)

Originally Posted by Kevin Purcell

I'm curious though. Why the edge to edge field requirement? I ID warblers by putting them in the center of the field. But the big FOV is good to follow the flitting so you can get the glimpse of the patterns to do the ID. Are you planning to follow them around the field with your eye?

The big FOV helps me get on the (oftentimes moving) birds and also to follow them when they're moving. The big Sweet Spot seems to help with IDs while bird(s) are moving, in observing multiples more easily, and in just simply seeing more better. When I've been "warblering" with 2 bins around my neck (or otherwise at my disposal), I have invariably preferred those with best combo of criteria 1,2 and 3 above. It's usually been 8x/8x or 8x/10x. I'm interested in the 7x possibility.

[APSmith]

Originally Posted by ceasar

The 3 criteria you list are important but I think another one should also be considered.

Depth of Field.

That is, the amount of the view that is in sharp focus in front of and behind the subject you are focused on or trying to get a good look at. Lower power binoculars, in general, have greater depth of field than higher power binoculars.

A binocular that has a lot of Depth of Field comes in real handy when looking into trees and brush, especially if the bird's distance is inside 50 feet or so.

Add this factor, and I think, of the three binoculars you have listed that the SLC 7 x 42 would be your best Warbler glass. 7 x 42's excel in this respect.

Cordially,
Bob

I agree - and came close to including that as number 4! I decided against it since I wanted to keep it as simple as possible and not give too much advantage to 7x. But nonetheless, your SLC vote is just the kind of input I'm after!

Thanks, APS

[Kevin Purcell]

Originally Posted by ceasar

A binocular that has a lot of Depth of Field comes in real handy when looking into trees and brush, especially if the bird's distance is inside 50 feet or so.

I'm never sure which I prefer for looking into trees or shrubbery.

A large DOF means less focusing and so less fiddling but everything is in focus so there's no seperation in the planes.

A small DOF means you can focus (figuratively as well as literally) on bird that has branches in front of it (and have those go out of focus).

I'm so fickle this will probably change from situation to situation. I was trying to figure out what a wren was today (I could hear its quite song from some very dense shrubbery). The bins I had had a moderate DOF. At points I would have prefered more DOF (I wasn't sure were the bird was: search mode). When I found it, in amongst the branches, I wanted a narrower DOF to defocus the annoying branches.

So we need a bin with a "DOF knob" on the side.

Thanks for the other feedback. It's always interesting to see other people's style. I'm still 7x/8x birder but I have to try the 10x style to see if it works for passerines for me (it does for static distant waterfowl but that's rather different).

I'm presuming the Zeiss 7x42 FL don't meet your FOV requirement.

[Pileatus]

Originally Posted by APSmith

I know this is a ridiculous title, and doesn't necessarily match the following, but:

ONLY considering the following three criteria, what's the best view?

1. Sweet spot/FOV size (overall field -not just % of view).

2. Ease of view: i.e. no blackouts, easy eye placement, shake friendly, etc.

3. Stray light control.

For the sake of this survey, I'm assuming good resolution and throwing out weatherproofness, weight, handling, eye relief,etc. From all I've read (mostly here), and from personal experience, the glasses to consider for the best combination of these three criteria might include: Nikon EII 8x30, Swaro 8.5x42 EL, Swaro SLC 7x42 (New).

What others should be included on short list?

Thanks, APS

A Nikon SE 8X32.

[Alexis Powell]

It's gotta be a 7x42 with good ergonomics and fast but precise focus. My past favorite was the Zeiss 7x42 Classic and I'm not sure its been surpassed. The Swarovski 7x42 is quite good.

--AP

[Blincodave]

The Swaro 7x42 is quite heavy. The Leica Ultravid 7x42 is my personal favourite. The Nikon 8x32 SE is superb, but can be tricky to use if the bird is very close.

Dave

[Pileatus]

Originally Posted by Blincodave

The Swaro 7x42 is quite heavy. The Leica Ultravid 7x42 is my personal favourite. The Nikon 8x32 SE is superb, but can be tricky to use if the bird is very close.

Dave

Dave,

One of the subtle beauties of the SE is that its IPD can be set as low as 53mm, thus minimizing or eliminating overlap in close quarters. My SE, at 10 feet, has always produced a crisp, unified view. The focus can be a bit slow, but I happily trade that for the "VIEW".

John

[Steve C]

When I'm looking at a tree full of warblers, I grab the Swift 7x36 Eaglet. I guess I have gotten used to the 374' FOV and don't have the good sense to realize it is "restrictive". The glass has a fast, responsive focus wheel, excellent depth of focus/field and its optics leave nothing for me to desire at warbler ranges. Even with a superior focus depth, it is still possible to rotate a more precise focus back and forth on the warbler in question to make unwanted twigs and other stuff dissappear and reappear in the focus field.

[APSmith]

Originally Posted by Blincodave

The Swaro 7x42 is quite heavy. The Leica Ultravid 7x42 is my personal favourite. The Nikon 8x32 SE is superb, but can be tricky to use if the bird is very close.

Dave

Remember, for the purposes of this survey, I'm not considering weight. Would you include SLC considering 1,2 and 3?

Also, could you elaborate on the "tricky" characteristic of the SE? (Is it the IPD as suggested by JT?)

Thanks much for your reply, APS

[APSmith]

Originally Posted by Kevin Purcell

I'm presuming the Zeiss 7x42 FL don't meet your FOV requirement.

FOV - Yes.

Sweet Spot - maybe ??

(Alexis Powell)It's gotta be a 7x42 with good ergonomics and fast but precise focus. My past favorite was the Zeiss 7x42 Classic and I'm not sure its been surpassed. The Swarovski 7x42 is quite good.

I've read somewhere here that the ClassiC has a larger sweet spot than FL. If so, perhaps it hasn't been surpassed.

As the SE slowly disappears (and goes the way of the ClassiCs), then the two very best will perhaps no longer be available.

APS

[UTCbirder]

Hello to everyone:

Our warblering here on the upper Texas coast is done under a variety of conditions, from open sea-scrub to the more famous live-oak woodlots, like High Island or Sabine Pass.

"Fall-outs", or groundings of massive numbers of transgulf passerine migrants, although uncommon, provide the best chances of those mid- to upper-20 warbler species days. At those times, a waterproof, bright, close focusing bin with a wide linear and apparent field is a must; some type of hydrophobic coating is a bonus.

Several of the locals here have settled on Zeiss FL's, either 8X or 7X. I use the 7X and can recommend it w/out reservations. I particularly appreciate the immersive depth of field.

[Blincodave]

Originally Posted by APSmith

Remember, for the purposes of this survey, I'm not considering weight. Would you include SLC considering 1,2 and 3?

Also, could you elaborate on the "tricky" characteristic of the SE? (Is it the IPD as suggested by JT?)

Thanks much for your reply, APS

Ref SE: JT is quite correct. I find the need to adjust the IPD when close to a bird. No doubt about it, they are remarkable binos. Yes, I would include the SLC considering 1.2 & 3. But do look at the Ultravid 7x 42 (another bino that JT and I share in common!)

Dave

[FrankD]

Hmm, the 8x32 EL?

:-)

Sorry, could not resist.

However, considering just your first two criteria (and not considering the 3rd as it is not something I am overly sensitive to) I would think that many of the high end 7x42s (FL, SLC, Trinovid or Ultravid) as well as the 8x32's (FL, Ultravid, SLC, Trinovid) would probably fit your criteria. All have average eye relief (15-17 mm on average) to help avoid blackouts and all, including the FL in 7x42 and 8x32, have more than adequate sweet spots. Ofcourse some are better than others but the more time I spend with the high end bins the more I am starting to believe a good portion of Stephen Ingraham's comments about centerfield sharpness versus off center sharpness.

Hmm, and just to throw another bin in the mix, how about the new Nikon EDG? I had the opportunity to handle the 7x42 and 8x32 recently and I was very impressed by them. If it wouldn't force me to sell the 7x42 FL and the Meopta Meostar 8x42 to afford them I would probably pick one up.

Speaking of which, you cannot really rule out the Meostar series either. In every area other than color fringing I think they are entirely comparable optically with the big four. I do not have any issue with blackouts with them, they have a very wide sweet spot and their depth of field is also quite good. I also cannot remember a time when I might have noticed any type of glare, flare or "glints" when looking through them. Since weight is not an issue I think they should be considered.

Realistically though Adam, since you are looking for a bin to equal the level of the 8x30 EII I think you are going to have a very tough time. John's suggestion of the SE 8x32 is probably the closest to the EII in most categories (excluding the blackout issue for some folks and the slightly narrower field of view). Though I am not telling you anything new you aren't going to find any bin at the $200-$300 price point that will match the optical performance and handling (weight in particular) of the 8x30 EII. Unless one of the companies decides to reverse current market strategy to come up with the ultimate porro experience you are going to have to resort to the high end roofs and all of them have their tradeoffs.

Hope this helps somewhat.

[Alexis Powell]

Originally Posted by FrankD

Hmm, the 8x32 EL?

I resisted naming the Swarovski 8x32 EL earlier even though it is the bino I actually use most for wood warblers in the trees/shrubs and fall sparrows in the grass and brush. It is close enough in performance to what I like so much about the Zeiss 7x42 Classic that I don't bother to extract the latter from storage much these days, but the 7x42 Classic still has the advantages that the larger objective and lower magnification bring--tremendous depth of field and an exit pupil so big you can almost see through the bino when holding it up to your eyes sideways (yes, an exaggeration) in the heat of fast action birding.

--AP

[NWBirder]

What determines the binoculars' depth of focus? I know camera can be controlled by the aperture size. For binoculars, the aperture size is fixed by the objective lens size. How does one pair have deeper DOF than the other given they have the same lens size? Does internally baffling a role here to intentionally step down the aperture size so to increase the DOF? Of course, the penalty of doing that is less brightness with smaller true exit pupil. Or it is handled by other design factors? Any experts out there?

[Kevin Purcell]

For a camera (i.e. a single lens system) it depends only on f/number of objective and magnification. For bins it's a bit more complex (IMHO).

The DOF of a bin is controlled by the

• f/number of the objective: this varies slightly from bin to bin
• effective f/number of the objective: given other aperture stops in the system including the entrance pupil if the eye which is usually stopped down which can vary with habitat.
• magnification: lower magnification bins have greater DOF.
• bin-to-subject distance: the closer you get the shorter the DOF. This can be a problem when close to a bird in shrubbery.
• DOF of the eyepiece: which most people seem to ignore but it has a DOF too magnifying the image presented by the objective. I think this is were most of the "these are both 8x42 why do they have different DOFs" issues come in
• the presence or absence of a field flattener (which decreases DOF) so if the bin gets a flat field this way then you can lose DOF.

There are several threads on this here and on cloudy nights.

The Wikipedia article is biased to cameras but it rather good

http://en.wikipedia.org/wiki/Depth_of_field

[Hermann]

By far the most important factor controlling DOF in binoculars is the magnification. A second important factor, far more important than, for instance, eyepiece construction or effective f/number of the objective, is the accommodation range of the human eye. It thus depends to a large extent on the age of the user as the accomodation range decreases with increasing age.

Taking 8x bins as an example, with the binoculars focussed to infinity: For a 30-year-old with an accommodation range of 7 diopters everything from 9.1 meters to infinity is sharp (8x8/7=9.1 meters). (Of course, in real life most people would refocus their binoculars at distances closer than, say, 30 meters or so, because it puts less strain on the eyes than continually focussing with the eyes.) For a 50-year-old with an accommodation range of 2 diopters things look rather different, for him the depth of field is a lot smaller, it's from 32 meters to infinity (8x8/2=32 meters).

This may in fact be one of the reasons why many older birders I know tend to get binoculars with lower magnifications, the other reason being that they find it more difficult to hold their binoculars steady.

Hermann

[NWBirder]

Kevin, thanks for the explanation. this is cool. thanks

[Kevin Purcell]

Interesting point, Herman.

I wonder if that leads to so many conflicting view on the DOF.

It changes the perception of the DOF but the physical DOF is still the same but the young observer can move that DOF around in the view i.e. a young observer can make the whole field look "in focus" but the portion he is fixated on will be in focus. For example the young observer should be able to bring the branches in front of and behind the bird into focus. And this is why fixed focus (and semi-fixed like independent focus) bins work well for younger users.

BTW, for those that want to estimate their accommodation range try this:

1. Wear eyeglasses to correct your distance vision (bifiocal wearers don't use the reading segment for this test)
2. Determine the distance you can clearly see an object close to you (bring it up to your eyes and measure the distance fromit to your eyes)
3. Your accommodation is about 1/D diopters for D in meters (or 39/D in inches)

For example, I'm 47 year old myope (short-sighted) who needs reading glasses (+1.5D add) have an accommodation of about 1.9 diopters. Not great. I won't be changing my depth of field too much.

However all that said I do have a collection of bins with the same magnification and the same aperture and they have different DOFs (with my same older low accommodation eyes ... that's a constant). In some cases it's difficult to determine why they have the DOFs they have e.g. the Celestron Ultima DX 8x32 porro has the worst DOF of all my 8x bins even though it has a small objective and I think quite a long focal length (i.e. a larger f/number objective) it is quite clearly worse than my 8x40ish bins. So I'm quite sure there are other optical factors in the DOF in some of these bins. BTW, this bin has quite large field curvature at the edge of field (and wide FOV 8.2 degrees) so it's not a field flattener issue!

Like stray light, DOF is not something that appears on a spec sheet and so is difficult to estimate without a hands on review.

[Tero]

This may in fact be one of the reasons why many older birders I know tend to get binoculars with lower magnifications, the other reason being that they find it more difficult to hold their binoculars steady.

I see a bird over there, Mabel, I saw it good (at 7x), looks like a song sparrow. I know you can't see it, but you still have good ears. It is that direction, can you confirm the song? Thanks. We better write it down, we will forget. Dang, I forgot my glasses.

Mabel: They are on your forehead Ed, as usual.

[FrankD]

Alexis,

I feel the need to comment about my earlier suggestion. I had given AP the opportunity to try out the 8x32 EL that I had in my possession. On paper it sounded like a very close matchup for what he was looking for. After some extended usage though he found that he still preferred the 8x30 E II to it. I will leave it up to him to comment further.