Telescope Reviews: IS binos

A slightly longer review of Newcon/Optik's 16x50 stabilized image binocular.

Almost everyone enjoys using Image Stabilized (IS) binoculars. For those who don't, there's a huge range of non-IS binos to choose from. For those that want an IS bino there's only a few choices. The Canon series, with their variable prism design. There are some gyro-stabilized units from Nikon and Fujinon and a few others. Then there are two mechanical system choices, the Zeiss 20x60 and Newcon/Optik's 16x50 and 20x50. These require no batteries which is a great big plus in their favor.

I have no experience with any IS bino other than the Newcon 16x50, except for a brief time at NEAF when I used the demo Canon IS bino for a few seconds. Despite this I hope to convey possible differences and similarities between the 16x50 and the Canon products.

These are very different designs. Canon with its mini-gyro sensor giving the microprocessor info and then generating control signals to a variable prism is the high tech digital solution. Newcon relies on a free floating prism assembly connected to the body of the bino by a damped gimbal suspension. Both are elegant and effective in their own ways.

The following comments refer just to the Newcon 16x50.

The 16x50 arrived in a smallish box with adequate protective material. A simple box and cardboard sleeve contain the bino, soft case and neck strap, and a single sheet of instructions labled as the owners manual. No four color printing or complicated interlocking styrofoam blocks come with the Newcon, just the basics.

The body is a two piece aluminum housing that holds the objective cells, prisms and the damped gimbal assembly and the button that releases the lock down on the internal moving parts. IPD is adjusted by rotating the eyepiece assemblies in or out. These assemblies are geared together so that moving one will move the other.

The body is sealed against the weather but I doubt it can tolerate full immersion for any length of time. The body is sealed well enough but the eyepiece assemblies look vulnerable at the focusers.

Many comment that having to hold the button down all the time is a big issue. Pressing the button releases the floating prisms from their locked down position. It doesn't require much pressure and once pressed in a certain amount, the pressure required to keep it depressed decreases. For me, the button was just where my thumb rests and was comfortable to use.

The focusers are a non-rotating helical design. The tension needed on the focusing ring was not uniform. One side was smooth but the other had some stiffness in it as the ring was turned. This problem improved over time but never went away completely.

The eyepieces have roughly a 70 degree AFOV. Given that the eyepeice is no larger than normal, the eye relief of 11.5mm is too short for those with glasses. The outer surface is coated but I don't know about the inner surfaces.

The objectives are cemented doublets housed in eccentric ring cells. This is a classic way to adjust alignment. In this case it's the only reasonable way to do it since the floating prism, well, floats and isn't accessable anyway. I found myself needing to adjust the vertical alignment so I wouldn't have double vision last year. I had to clean the sealing grease off the entire eccentric assembly so I could align the bino. Once cleaned, getting it into conditional alignment wasn't too bad. I found that I had to mount the bino and press a marble gently against the button to float the prisms so the image wouldn't jump too much when activating the stabilization. No, this wasn't included in the one-page owner's manual.

The objectives do have AR coatings, but they seem to be The MgF type. The coating is much more subtle than the images on the website would lead one to believe.

Does it work? Of course it works. Press the release button and the shakes just dissapear. Detail not visable jumps out and noticably improves the image. I'm sure all IS devices give similar effects as the Newcon does. Since it's mechanical there is a swaying back and forth with modest movements, The system is close to being critcally damped which means for an impulse, the suspension moves back and forth only once and then comes to rest. In this case it's still moving slightly after one cycle. If a jolt or movement is too large the prism bumps into the bumper at the limit of it's movement. Say bye-bye to a stable image and lock the mechanism by releasing the button. Most users will be able to hold it steady enough to enjoy a stable image. Most will easily learn how much movement the bino can cope with before bouncing the prism around.

The damping is achievied with the use of a balanced rod extending from the gimbal near the rear of the bino to the front of the housing body. There's a mass at the end which rests between two other masses. I guess it's magnetic since there doesn't seem to be any other shock absorber or piston anywhere else inside the body of the bino. I might be wrong about this, it wouldn't be the first time. I get the feeling that this bino is designed mostly for terrestrial use. If the damping rod is long and horizontal it works fine. When the unit is pointed straight up the effective length of that rod shrinks and the damping effect is minimized. Not the way an astronomical device should be designed in my way of thinking.

The device seems crippled from the start with the vignetted design leaving a small 2.2mm exit pupil. I believe this has to do with the floating prism design. As the body moves and twists, the gimbaled prisms stays essentially motionless. This means that the objectives and the eyepieces are moving in relation to the prisms. I suspect that the design limits the view of the prism to 35mm so that as it sways around off axis it still sees a 35mm objective and does not encounter the edge of the objective and have a sudden decrease in illumination. This gives about 7.5mm ring around an imaginary 35mm central diameter for the prism to sway without seeming to change illumination. The Canon binos don't have any of these concerns since the erecting prisms are fixed and the variable prism isn't swaying but is changing the angle of it's face or faces. This critical difference allows the Canons to be used at night and the Newcon only in the daylight.

In their website, there is a picture of a 16x50 with image intensifiers attached to both ep's. I believe that would cure it's night blindness in a big way. These night vision units are not imported to the US for what I can only imagine are security reasons. Shucks.

Once the limitations of the Newcon are accepted it performs very well. It's designed to be used from a moving vehicle and it does this beautifully. Using the 16x50 from inside a moving car, license plates at a considerable distance become steady as stones when the unit is stabilized. It also makes a handheld 16x device easy to use.

One added feature is that it works equally well upside down. if your left thumb gets tired, just turn it over and operate the button with your right forefinger. This is apparently what they did to give the 20x50 it's own "look". From what I can tell it's just an upside down 16x50 with differant eyepieces. Since they have to be a shorter focal length to get 20x, the eye relief may become even shorter unless a more sophisticated ep design is used.

I hope that answered some questions people had about the mysterious Newcon IS binoculars.

Peter

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Peter

Telescopes 25 - 318 mm
Binoculars 15 - 88 mm
Microscope 50x - 1000x

Edited by pcad (11/16/06 11:22 PM)