monoculars?

Hi all, i’m interested in buying a monocular. I’d like one thats compact enough to fit in pfd pocket and of course waterproof while out kayaking. It will be used for watching the critters and spotting promising campsites along the shoreline.

Any suggestions? Or should i be considering very compact binoculars instead? So far i’m thinking about the Brunton product found here:



http://www.brunton.com/product.php?id=575

thanks for any info.

Just make sure of one thing:

– Last Updated: Apr-10-10 4:45 PM EST –

There's one thing that CAN be very important. You may want to be sure you get something with the appropriate "exit pupil" diameter. What's that? Take the objective diameter and divide it by the magnification, and that gives you the diameter of the "shaft of light" coming out of the eyepiece. On the monocular you are considering, the exit-pupil diameter is 2.75 mm.

If that shaft of light coming out of the eyepiece is not as large as the current working diameter of the pupil of your eye, the image will be too dark to see properly. Anything less than 3 mm becomes just about worthless once the sun gets close to the horizon, but will be fine on the average bright day. An exit-pupil diameter of around 5 mm is very good at dawn and dusk (and is pretty good at night if the moon is out), while 7 mm will work nicely all night long. Optics with the larger (low-light friendly) exit-pupil diameters are easier to use in bright light too, since the alignment with your eyes is much less critical (the image won't have blacked-out edges if your alignment wobbles a little bit, but that happens pretty easily with "daytime only" optics).

The discussion of optical quality is much more complicated, and by necessity requires you to balance price against image quality.

Ziess MiniQuick

– Last Updated: Apr-10-10 8:11 PM EST –

I have a Ziess MiniQuick that is the easiest monocular to carry that you'll find. It about the same length and diameter as a Sharpie marker and just as easy to carry. I think it weighs 3/4 of an ounce. It is not waterproof. It is only 5X, although anything much more powerful is going to be shaky even on solid ground. Monoculars lack mass so are more prone to shaking.

Monocular

– Last Updated: Apr-10-10 9:48 PM EST –

A few weeks ago a buddy showed me his new, monocular "toy". It was just what I wanted;I had been thinking about buying one.The hunt was on. Got a lot of "out of stock" replies at places I checked; just as currently on the Brunton website. Finally went to ebay, and glad I did. Ended up paying about half of Brunton's advertised price, with shipping included.

Brunton Eterna
6 X 30 power
341 foot field of vision at 100 yards
waterproof
fog proof
nitrogen purged
5 mm exit pupil
19 mm long eye relief
Size 6" X 2"
Weight 11.5 oz.

I don't notice any shake at all with it; that's one of the reasons I started looking for that particular model in the first place. I think with a little practice, I'll soon be able to hold it & adjust the focus with the same hand.

I do notice some shakiness in the Nikon Action 8 X 40 power binoculars I bought my wife.

I am no optics expert, but I did get what I wanted.


BOB

a few things …

– Last Updated: Apr-10-10 11:14 PM EST –

...... "exit pupil" size (mm) is the objective lens' mm size divided by the mag. power . Example : 30 mm / 6 x-mag. = 5 mm (exit pupil) .

"twilight factor" (a little more on this later) is the objective lens' mm multiplied by the mag. power , and calc. the square root of that multiplications' product . Example : 30 mm x 6 x-mag. = 180 , then calc. the sq.root of 180 ... 13.41 twilight factor (rounded down) .

As gbg stated the larger the exit pupil mm # , the more light the eye will receive (or perceieve) . To a certain point the exit pupil mm # (size of light) can be a valuable asset , but not nessasarily definitive as better because there are many excellent optics that have rather low exit pupil mm #'s , and many basic (or poor) quality optics have high exit pupil mm #'s .

If we are looking for high resolution detail with high mag. powers , the exit pupil mm # may be rather small , such as in high quality or comp. rifle scopes .

Too high of an exit pupil mm # can be just too much light for the eye to receive (this causes a wash out effect which deteriorates detail as the exit pupil mm # gets higher - you can also relate this to a picture that was taken with too high of an OEV setting , too much light let in) . The human eye pupil has a general range of between 5 mm - 7mm , thus between 5 mm - 7 mm exit pupil # is optimum for relieving eye strain (or in other words , not having to strain focus on a smaller exit pupil mm # found in the high reso. comp. scopes , which requires careful eye adjustment to the eye piece to avoid the black out problem ... or too high an exit pupil mm # which cause eye strain in attempt to gather detail through the wash out) .

Twilight factor used to be a fairly important consideration (and to some extent still is) , more so before the greatly improved coatings that are being used on optic lenes of today , which allow greater clarity and less distortion of light transmission through the veiwing instrument . In general the higher the twilight factor # is , the greater the resolution detail will be in lower light conditions .

These are just some things to think about when selecting optics . There are many other factors that relate to optics quality that effect the final product your eye (or a camera , etc.) sees .

Depending on ones' objectives (desires) for an optics' performance , and how comfortable they are with a given resolution (clarity) ... there are a wide range of optic options available .

My field glasses (Leupold- Cascade) are 8 x-mag. x 42 mm (exit pupil mm # is 5.5) , and the twilight # is 18.33 . They have fairly sensitive (good but not excellent) low light capability , and pretty good resolution detail ... but nothing like a higher end optics (more expensive) from say Zeiss .

I wouldn't expect much from the Brunton 8 x-mag. x 22mm Lite-Tech for 28. bucks (probably like a toy ??) , but the other Brunton (Externa) thebob has mentioned should be pretty nice .



I must clarify one thing.

– Last Updated: Apr-11-10 12:36 AM EST –

To say that that having too large of an exit pupil can create a washout effect, like over-exposure with a camera, is not correct. The reason that is not correct is because the pupil of the eye contracts in response to increasing light intensity, as we all know. When the pupil of the eye contracts in this way, it simply captures a smaller cross-sectional area of the available "light beam", whether that beam consists of the shaft of light exiting the eyepiece of a monocular or the full and complete area of light reflected from a scene who's rays are passing in a passing in a particular direction. In other words, what happens when the light is too intense within a large exit pupil shaft of light is the same as what happens when NOT looking through any optical instrument at all (because when not looking through optics, the "width of the exit pupil" available for viewing is unlimited in size).

To say it as briefly as possible, optical instruments such as binoculars and monoculars that have an exit pupil that is "too big" simply allow the extra area within that shaft of light to be "wasted" by never passing through the pupil of the eye at all. It is NOT necessary for the eye to capture the full area of the exit pupil to create a crisp image. Collecting the light within any portion of that shaft of light will do, though when only a portion of that light beam is utilized, the best image will be obtained from the center (however, with good-quality optics, you won't notice the difference).

Give the guy a break!
–he doesn’t need a lesson about Hubble optics.



We recently got the Brunton: It’s cheap, waterproof, and it works. My wife found that binoculars were too cumbersome to use effectively in her boat. All I know is that she’s really happy now.

thanks
I’m looking also.



I appreciate this answer. It tells me what works. I don’t need to know how it works.

Brunton
It’s a little different than the one you referenced. I really like it. Sometimes forget to take it though!

Audabon
After dumping with my waterproof Brunten which leaked and wasn’t very clear anyway,I bought an Audabon 6x(which is the max power you want for this use) which is perfect and clear and light,small and cheap-but not waterproof. I carry it in a plastic bag.

Turtle

I’ve had the Brunton 6x30 for years…
…and I find it to be ideal for use in a kayak and for many other activities. It’s compact enough, sharp, bright, well armored and doesn’t require focusing.



The smaller, cheaper 8x22 optics (which are sold by a lot of companies) are much lower optical quality, plus the higher power combined with less weight means more shaking and the smaller exit pupil reduces their brightness markedly. Many of them are NOT waterproof, either. This is a case where you really do get what you pay for, but they’re better than nothing.

Which Brunton
Which model was it that leaked?

Did Brunton honor it’s warranty, or did you not even bother to return it?



BOB

Brunton 6x30
The reason I like mine is that since I wear glasses I can fold over the rubber lip and get closer to the eyepiece for a better image.



http://www.amazon.com/Brunton-F-4070W-Eterna-Monocular-6X30/dp/B000093IKU

monoculars
I swear by monoculars for paddling over binoculars, at least while on the water. Much easier (for me at least) to use effectively.



I’ve gotten by for the past 3 years with this one:



http://www.dealextreme.com/details.dx/sku.3899



Best $10 I’ve ever spent. Not waterproof though.



I got this one last christmas, not sure if I will be my in cockpit monocular, this one is more for astronomy at the campsite:



http://www.telescope.com/control/binoculars/waterproof-binoculars/orion-10x42-waterproof-monocular

I use binoculars…
I take compact binos, work well for scouting or checking out wildlife. If its too rough for using binos, I figure a monocular wouldn’t work much better. A mono might be better in that it fits in a pfd pocket, but I just keep the binos tucked inside my pfd when not in use, or in my lap bag or day hatch…

Minox
I’ve been using a Minox made monocular (couldn’t resist the alliteration) for about 4 years. It is 8x16 and has excellent optics. Friends who compare their $25 Brunton monocular to the Minox are amazed at the difference in clarity and color. I didn’t pay $150 for it but would if it is ever lost. It has been tucked inside my pfd pocket in some interesting seas and, though not waterproof, has not had any problems. The sliding adjustment is excellent.

That’s Funny!

– Last Updated: Apr-11-10 10:59 PM EST –

People here talk about the factors which make one boat better or worse for various uses all the time, yet there will always be some guy who buys a Pelican canoe and thinks that oughta be good enough for anyone else because they've never paddled anything better. That kind of person might even complain about someone giving lessons in naval architecture when advising that a Bell Yellowstone is a better boat for twisty rivers than a Bell Magic. That stuff about exit pupil is anything but complicated and will be found in any buyers guide about binoculars or monoculars because it is necessary information that first-time buyers don't usually know. It could easily be all the information a person needs to avoid spending hard-earned cash on a monocular that doesn't meet their expectations. You say that you are happy with the same monocular mentioned by the original poster, and if a model that needs really bright light to function suits your needs, that's great, but you could let the original poster decide which one to get based on a better reason than that provided by a person who only says "this one works for me".

I don't say "get a Pelican" in response to every question about canoes either, but I'm sure there must be somebody out there who thinks that's awful.

We have the Brunton Eterna
and we like it a lot although it is not considered compact to me. I have a waterproof otter box that i put it in and fits pretty good. It is only 6x but it works decent for most things. Just this Tues i handed mine to a Ranger who liked it also - we were watching a boat with 2 occupants from shore that were in trouble.



I bought the small cheap Brunton first but something was wrong with it and decided to pass on another one and buy a better quality design.

steadying the viewed image …
… in the upper ranges of exit pupil mm # , a 7 mm for instance , makes it easier to keep the veiwed image still (or stiller) . higher exit pupil mm #'s are often prefered for marine use for that reason .










paddlesheep, I would venture to …

– Last Updated: Apr-12-10 12:26 AM EST –

...... guess that the 10x42 you have has a "very good" low light sensitivity , even though the exit pupil mm # is 4.2 . This is not saying the optical clarity (detail) is exceptional , it's not saying that it isn't either ... clarity is a factor relating more to the optics quality (which I couldn't know about that brand and model) .

A 10 x 42 optic has a twilight factor of almost 20.5 .