This is why I would suggest trying to mount your binocular onto a steady base like a tripod if you are going to use any magnification above 12x to 15x. Thus I feel it is a shame that these binoculars are not easily tripod mountable using a standard binocular tripod adapter and thus to do so you will have to think a little outside the box and come up with your own plan or at the very least try and rest your elbows on a steady surface like a table.

At 20x power these are advertised as having an angle of view of 2.6° (45m @ 1000 meters / 135ft @ 1000 yards) which is very narrow and indeed it feels it when looking through them. An important thing to consider when looking at the size of a compact binocular is how small they are when they are folded. When you are are looking through them, just how small they are is not that important, but size is far more important when you carrying them around with you. Different designs of compacts fold up in different ways and this can make a big difference is their size. The twist-up eyecups look to be made from a very hard plastic that have a very thin rubber coating on them. The ocular lens has a diameter of 11mm and the eyecup has an external diameter of 37mm, which are both considerably smaller than what you find on most full sized binoculars, but is about average for a compact. This smaller size and very thin rubber covering mean that they are not the most comfortable eyecups that I have ever used, but any discomfort is only really noticeable when you push them quite firmly against your face. Caused by chromatic aberrations, the level of color fringing that is observable around the edges of contrasting objects becomes a little more evident at higher magnifications. Even so and especially at lower powers, I feel the amount is more than acceptable for a binocular in this price class and thus I would say these do a reasonably good job of keeping it to a minimum. AB, DD, IV, KW, PH, FK, FY, TR, PA, KA, LL, PO , SA, CA, DG, EH, EX, G, LD, ML, PL, SY, TA, TD AND TQ.

You must remember that as well as the Exit Pupil, the performance of a pair of optics in poor light also depends a lot on the quality of the glass and optical coatings and not just the exit pupil and twilight factor formula. Good coatings on the lenses and the prisms can double the amount of light that gets through the binocular, when compared to those that have none or poor quality coatings. As you would expect, keeping the image nice and still becomes harder and harder as you increase the magnification settings. At 24x I was able to the image still enough to take in all the details of what I was looking, but I had to concentrate on staying very still as even the smallest movement has a big impact on the amount of image shake. This is fine for short bursts, when you just want to take in a bit of detail, but is definitely not something that you would want to do over longer periods.

At no time did I detect any other obvious deformities in the view and once correctly focused was reasonably sharp and looked perfectly flat even at high magnifications, which in my experience, especially for a low cost zoom binocular is certainly not always the case.As you decrease the power, this widens to a maximum of 4.6° (80m @ 1000 meters / 240ft @ 1000 yards) at 8x power, which has to be said is pretty narrow if you compare them to an average 8x binocular. As to be expected, in good light conditions, there was no real noticeable difference in image brightness between these and a couple of other lower costing 8x and 10x compacts that I have with me that I compared them against when I had the magnification adjusted to the lower levels. Indeed good light, you only really notice the drop off in image brightness once you get close to the maximum magnification settings. However at 20x power, it did look like I was looking down a straw, even with the eye-cups fully folded down and thus I would not recommend these should you need to wear your glasses whilst binning. inches = centimeters / 2.54 Using our centimeters to inches converter you can get answers to questions like: At 12x Magnification:When you increase the magnification on these Eagleviews to 12x their Exit Pupil reduces to 2.08 (25/12) which means that less gets to your eyes.

I also really think the Gator is a fun little compact binocular to play around with and thus another definite use could be as a set of binoculars for older children to use. Now usually I recommend get a low powered binocular for kids as it makes them much easier to use. But with a zoom binocular like these, they can start off at the low 8x setting and then zoom into objects which I know for certain most if not all kids will love! For a zoom binocular the optical stats a more complicated than your typical fixed magnification instrument as the field of view, close focus distance and they eye-relief will all vary as you adjust the power and thus you need to consider they whole range and only compare them to other fixed binoculars when you have them set at the same magnification. This is not the case with the Discovery Gator 8-20x25 binoculars and whilst the best image I could achieve after fine tuning the focus wheel was still not quite as sharp at 20x as that which I saw at 8x, it really was not bad at all, which for me is actually impressive for a compact zoom binocular at this price.By opening and closing the central hinge, you can set the eyecups to match the distance between your eyes. On these, they go from a minimum of distance of 5.2cm apart, right up to 7.4cm. It has been a long while since I last tested a pair of binoculars with a variable magnification. This is mostly down to the fact that I generally advise most people against getting a pair of "zoom binoculars" because whilst they may seem like a great idea, in reality it has been my experience that they often turn out to be disappointing and the downsides usually outweigh the advantage of being able to zoom into a view. These Discovery binoculars do have this function, but it is accomplished by turning the right eyepiece, which is a little different to most that have a separate adjustment ring. Either way, I found the diopter to work well enough and the ±3 adjustment range is pretty good for an instrument in this class.

At 8x magnification, I was also really impressed by just how little softening of the image on the periphery of the view there was and you can only just notice it by really looking for it. At higher magnification levels the amount of softening increases and becomes much more noticeable at 24x.This Nikon compact has, what I think are actually two hinges (it is hard to see as they are located under a cover), with both hinges located very close to each other, meaning that they almost work like single a central hinge design. Whatever the case, the two barrels can be brought closer together or pulled further apart to match the distance between your eyes ( Inter-Pupillary Adjustment) by opening or closing the hinges. This adjustment felt smooth and there was the right amount of friction to prevent them from opening or closing too easily, but not too much so as to make moving them difficult. The minimum distance between the centers of the two eye-piece lenses that can be achieved is 56mm when fully folded and the maximum is 72mm when full opened. As the simple eyecups are not really adjustable, there is not a lot you can do other than for them completely down or use them at the maximum setting. Other than to say that the objectives have a 25mm diameter and that the oculars are just over 12mm in diameter, I can't really expand as no information is given. It takes about 2½ turns of the wheel to go from maximum focus distance to the minimum. Thus I describe these as having a low geared focus mechanism. The advantage of this is that it makes fine focus adjustment easier, but on the flip side, it takes longer to make large focal adjustments than on those which take less turns. Whilst I would not expect a low cost binocular like these to have the same build quality as a top of the range pair that costs ten times as much, but I still want them to be tough enough to handle most normal bumps and scrapes and still want them to feel like you have a good quality optical instrument in your hands and not just a toy.