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-   -   New owner's question on Bushnell 7x26 E2 Custom (https://www.birdforum.net/showthread.php?t=327686)

JohnZL Wednesday 6th July 2016 15:19

New owner's question on Bushnell 7x26 E2 Custom
 
Hi,

I just received the Bushnell 7x26 from amazon.com yesterday. It is my first binocular. While checking it out I noticed that a few things:

1. The manual says I should adjust the Interpupillary distance (IPD) so that the views from both eyes merge into a circle.

My problem is, if I adjust the view to become a circle, I get dark edges on left/right sides of the view field. I need to slightly enlarge the IPD so that the merged view circle becomes a ellipse-like shape to avoid the dark edges. I tried with or without wearing eye-glass (adjust eyecup down/up accordingly) and the experience was the same.

2. My second observation is that the sweet point of view from the above adjustment is too narrow: if I move my eyes slightly, which happens a lot since I'm hand holding, I start to get dark edges around the edge of the view. The center of the view is always bright & sharp.

I just want to check if this is normal or my exception was too high. I have a feeling maybe that's 'you get what you paid for'. Will the Leica 8x20 BCA be better in this regard, since it costs 2x the money?

Thanks,

John

Binastro Wednesday 6th July 2016 17:21

Hi John and welcome.
Were you testing at a distance or close up?
I would do further tests in different lighting conditions.
It could be the binocular is out of alignment.
Or the collimation process produced the elliptical image.
Or your eyes need prism correction.
Or something else.

P.S.
Or maybe your eyes are not in the correct position along the optical axis.
Maybe they need to be further or nearer to the eyepieces?

Bencw Wednesday 6th July 2016 18:54

Hi there,

I'm not familiar with this model, but I have had a similar problem with a Bushnell, and found that actually the twist up eye cups were not fully extending, combination of me being a bit too gentle and something making them stick, but after twisting them right out once, the resistence went. I know it's probably not likely, but thought worth mentioning.

typo Wednesday 6th July 2016 18:58

John,

I had the Elite for three years and had none of the problems you describe. However it can be tricky to get the eye relief just right. The eye cups are too small to rest in the eyesockets (even if they extended enough) so I needed to use a finger between the focus and the brow to set the distance. With glasses the 16mm eye relief is actually a little long for me and I had to fix the eye cups about 1mm extended. However, many with glasses need more than 16mm. Just a guess, but it sounds like your eyes are too far from the binocular and that you might need to get a bit closer to the eye lens if that's possible. If you are too close you get what we call kidney-beaning or blackouts. The eye relief is only 15mm on the Ultravid and barely sufficient with my glasses and I found the eye positioning more critical.

The Elite does have more field curvature than some, which is good for perceived depth of field. However, in low light the sweet spot will appear much smaller than in bright conditions.

I thought the Elite was a great little binocular, but It was replaced in time by models with a bigger exit pupil and better weather protection.

David

JohnZL Thursday 7th July 2016 01:38

I used the indoor mirror method found on the internet to check collimation and the alignment seems to be fine. Maybe it's because the exit pupil is too small? I did experience a lot of edge darkness in one eye or another if I just move my eyes a bit. I tried both with and without wearing my eyeglass and the result was the same. I just had my eye examine a few weeks ago and the doctor did not mention I need prism.

I will probably return this to amazon and get one with bigger exit pupil instead. I originally wanted to have either the 7x26 or the Leica BCA. Now it seems compact binocular may not work for me at all.

[email protected] Friday 8th July 2016 00:11

Quote:

Originally Posted by JohnZL (Post 3424195)
I used the indoor mirror method found on the internet to check collimation and the alignment seems to be fine. Maybe it's because the exit pupil is too small? I did experience a lot of edge darkness in one eye or another if I just move my eyes a bit. I tried both with and without wearing my eyeglass and the result was the same. I just had my eye examine a few weeks ago and the doctor did not mention I need prism.

I will probably return this to amazon and get one with bigger exit pupil instead. I originally wanted to have either the 7x26 or the Leica BCA. Now it seems compact binocular may not work for me at all.

I had the Bushnell 7x26 and I had the same problems you did. It depends on the depth of your eye sockets but for me and you obviously the Bushnell's eye cups are too short for it's eye relief so you have to hold the binocular away from your face to see the full FOV. This creates all those problems you are talking about and the smallish exit pupil makes it even more difficult giving you all kinds of blackouts. For this same reason all compacts are finicky when it comes to eye placement and comfort. The bigger the exit pupil a binocular has the more comfortable it is. I have had many compacts and although some are optically excellent you really have to be ready for some optical tradeoffs for the advantages of the compact size. The Leica BCA is even worse in regard to finicky eye placement compared to the Bushnell. I would recommend getting an 8x32 or 8x30 porro or roof for an all around binocular. If you want to stay under say $500 I would recommend a porro like the Nikon 8x30 EII because you get better optics for your money than most roofs. Here is one on Amazon.com since you are buying from Amazon.com.

https://www.amazon.com/Nikon-Binocul...nikon+8x30+EII

JohnZL Friday 8th July 2016 17:03

I wanted to give the 7x26 another try. With the eye caps fully raised and pressed against my eyes firmly, something just did not feel right: even slight eye movement will introduce loss of light. When I backed off my eyes by 1/4 inch and all of a sudden the view field brightened up and all the blackouts are gone!

I think what I experienced is loss of light when eyes are placed within eye relief (or something like that when I searched for the blackout symptom). I thought high eye relief is a good thing but the eye cap on 7x26 is a bit short for me at least.

Unfortunately holding the Bushnell 1/4 inch from my eyes is not how I expect to use it in the field. If someone can point me to an aftermarket eye cap that is higher than the one on 7x26 I may consider keeping it.

14Goudvink Friday 8th July 2016 20:18

Try holding the bins with your forefingers against your eyebrows and you middlefinger(s) on the focus knob. In this way you can regulate the distance between the bins and your eyes quite finely with your forefingers.

Once you get used to this method it is very natural. As a nice by-product of this way of holding the bins shakes are dampened and you get a very stable view.

Good luck,


George

ceasar Friday 8th July 2016 22:36

I can't press any binocular (with the eye cups raised) up against my eyes without seeing blackouts.

I have to brace the top of the eye cups up against my brow ridge just under my eye brows to get a clear view which is why I prefer large firm eye cups and at least 15mm eye relief. Large eye cups are not hard to find on 42mm binoculars and on some 30/32mm binoculars but I find I can also use my older Bushnell 7x26 with rubber fold down eye cups this way.

Experiment a bit with this technique and see if it helps you. You might have to tilt the binocular up very, very slightly.

Bob

Aquaman Tuesday 19th July 2016 09:07

Just adjust the binoculars for your comfort. You are going to need to do the same no matter what brand or model you buy or how much you spend.

These are optical instruments that depend on YOUR eyes to function at all, and so it is commonly recommended that you try them out before spending money. That said, you already own what many, many people consider the finest example of their type, so spending more money is something you ought to do if you simply want to spend more money for the sake of spending more money - you won't be buying something optically superior.

I don't know how old you are, but spending twice the money never buys twice the quality or performance. It's like asking since you bought a Porsche and don't like the dual clutch automatic transmission because you can feel it shifting when you press the gas, should you buy a Ferrari? Because it costs more it must shift so you can't feel it shift, right? The answer is NO, what you are asking about isn't a matter of optical quality, it's an issue of not knowing how to use the instrument and not having any experience before making a purchasing decision.

You already have a fantastic pair of binoculars. Do some research and spend some time looking through various pairs of binoculars before you spend any more money.

Or just buy a pair of Leicas and tell everyone (who doesn't immediately walk away) how awesome and superior your Leicas are because they cost more than those crappy sub-par Bushnells you also purchased. Your call :)

Stephen Prower Tuesday 19th July 2016 22:28

Customisation of Bushnell 7x26
 
4 Attachment(s)
John ZL

In case it helps, I attach photos of a fully customised Bushnell 7x26 Custom Elite.

I don't wear glasses when using a binocular.

1. As shown in the Photo (1), I first used a piece of bicycle inner tube to fix the eyecups of the Bushnell in the up position. The eyecups would slip down too easily.

I then sleeved a second piece of inner tube over the first piece, and rolled it back over itself. I did this in order (i) to widen the eyecups, and (ii) to extend the eyecups by some 3mm. The purpose of doing so was respectively to:
* Make the eyecups more comfortable
* Assist the placement of eyes at the point of eye relief.

2. As shown in Photo (2), I went on to cut a third piece of inner tube in the shape of wings, and sleeve it over the first and second pieces. The purpose of fitting the wings was to:
* Cut out side light from the sun, etc
* Assist the placement of the eyes at the centre of the exit pupil.

3. Photos (3) and (4) duplicate Photo (2), except that they show the rainguards that have replaced the 'hangover' eyecaps that appear in Photos (1) and (2).

First I tried the skimpy rainguard that is shown in Photo (3). But it would not stay in place. So I replaced it with the full-bottomed knock-off rainguard that is shown in Photo (4).

The rainguards are made out of plastic sheet cut from the sides of a 4-pint milk bottle. The sheet is cut and bent to shape, and then skinned with duct tape.


Stephen

ceasar Tuesday 19th July 2016 23:07

Very nice, Stephen!

I see you have left room in photo #2 to adjust the diopter. Can this be done with the cups in #3 and #4?

I have this binocular and I like it very much but its diopter ring moves too easily.

Bob

Stephen Prower Wednesday 20th July 2016 00:23

Bob

You're right! I have frozen the diopter ring.

I suspect it's an accident. On other binoculars I have stiffened up the ring without freezing it up entirely.

I shan't try unpicking things for now. It's late at night, and I have to get up early tomorrow. But I shall have a go tomorrow or the next day. I daren't say definitely tomorrow because it's very hot here; I have a cycle ride tomorrow morning; and I may flake out afterwards.


Stephen

Stephen Prower Wednesday 20th July 2016 22:08

Bob

1. Photos (1) and (2) can be said to show the 'back' view of the Bushnell 7x26, while Photos (3) and (4) show the 'front' view. The diopter ring is shrouded by an elevated section of bodywork in front view.

So the diopter ring is accessible.


2. I have de-frozen the diopter ring.

I recut the middle piece of inner tube from a length of tube of slightly greater diameter than the diameter of the original piece so that it fitted less tightly. I then reassembled the pieces of inner tube on the diopter side (and also, in order to match sides, the non-diopter side).

In fact the diopter ring is made to rotate less freely by the bottom edge of the first piece of inner tube (ie the piece that freezes the eye cups in the up position) pressing down upon it.

So when fitting the middle piece, I must have caused the freeze by dragging the bottom piece a little further down at the same time.

The lesson learned is that one can't have enough lengths of inner tube of different diameters.

Local cyclists will have to favour me by having more punctures!


Stephen

Stephen Prower Monday 25th July 2016 13:42

Bob

Correction to Post #11

My memory served me wrong: I must have cut the plastic sheet for the rainguard from a 6 pint plastic milk bottle, not a 4 pint bottle. I have just made another rainguard, and found the dimensions of a 4 pint bottle to be too small. Even with a 6 pint bottle, things were very tight. It's because I don't make rainguards from separate pieces of sheet, just cut, fold and skin a single piece of sheet sized about 4in by 7in.

Stephen

ceasar Monday 25th July 2016 14:57

Stephen,

I think you are on the right track in post 14. If you can put the right winged eye cup on after the diopter has been set so that it will keep it from moving about freely the problem I described will be solved.

Bob

Stephen Prower Tuesday 26th July 2016 20:50

Bob

I had a look, but the raised section that part-shrouds the diopter ring prevents the base of the wings from being lowered enough to cover the ring. It seems that the job of making the diopter ring rotate less freely has to be done by applying friction to the ring from the top rather than the side.

Stephen


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