IMAGE STABILIZED BINOCULARS
By Silvio Jaconelli
It all started with me reading about quick-setup binocular mounts ranging from broom handles to parallelograms in order to steady up the images seen through conventional binoculars – the ‘shakes’! My binoculars of choice were Fujinon 7x50s - absolutely gorgeous images – and at 7 power, these were close to the ‘hand-held’ threshold of 10 power; many commentators have written that steady images are hard to get at higher than 10x without some sort of mount. And yes, even at 7 power I was getting the ‘shakes’. I have a camera tripod that I used as a mount, but the viewing angle was most uncomfortable, and it was a hassle to drag the mount out every time I wanted to do some serious binocular observing. Much more extreme were the Miayuchi 20x100 binoculars that I once had – it was mandatory to have these mounted, and the setup/take down hassle was almost as complicated as a small telescope. What was I to do …… ???
Well, I started to take notice of image-stabilized binoculars – they promised the ‘grab-and-go’ observing experience that I was looking for, so I started to read up on them. There was a very good review written in the July 2000 edition of ‘S&T’ which – along with everything else that I had been reading – gave high praise to the Canon models of image-stabilized binoculars. The closest that I came to a real live human being was an acquaintance of Bill Dellinges who had just purchased a pair and had told Bill that they were excellent binoculars. Peer pressure …..!! I finally succumbed, and I traded in my Fujinon 7x50s plus cash for the Canon 15x50s.
So what are the specs on these? The model that I ended up with - 15x50s - have ED objectives, 15mm eye relief, a 4.5 degree FOV, and weigh 2.7 pounds. They sell for around $950 new. There is an 18x50 model that sells for around $1200, but the FOV here is 3.7 degrees. Hmmm – I figured that I’d settle for the wider FOV and save myself $350. The weight of these is very reasonable – not much different from the Fujinon 7x50s. And there is no need to worry about the ED objectives getting scratched - the objectives are protected from the elements by clear optical windows, so what you see from the outside is the optical window and not the ED objectives. By the way, they use 2 x AA batteries, and these should provide 2 to 3 hours of observing time with typical Arizona temperatures. They are designed to compensate out any movements less than 0.7 degrees, which means that they eliminate all low level ‘shakes’; moving the unit by more than this distance will result in movement in the eyepiece views.
Let me digress for a moment and talk a little about the magnification/aperture combination. There is a body of opinion that states that the best way to rate how much you will see from a given binocular – the visibility factor - is to multiply the objective size by the magnification. Bigger objectives give greater light grasp, while higher magnifications will let you see fainter objects as well as darken the sky glow. So my (excellent) Fujinon 7x50s would score 350 (7 multiplied by 50). A pair of 10x50s would score 500, the higher score being the result of their ability to show fainter objects & to lessen the sky glow. Using this rating system, the Canons would score 750. Do I agree with a doubling of the score versus the Fujinon 7x50s ? I don’t think it’s that extreme, but having said that, there is no way that I would trade back to the Fujinons – the Canons are far superior for what I use them for. Conventional wisdom states that a mount is required to do serious binocular observing above 10x due to the ‘shakes’, and this is where the image stabilization factor kicks in – it raises this 10x ‘mount’ threshold. And rating them to the Maiyuchi 20x100s ? Well the Maiyuchi’s would score 2000, and that I’d agree with – AS LONG AS THERE IS NO PENALTY FOR BEING TRIPOD MOUNTED. I have never seen such perfection in a binocular as I did with my Maiyuchi’s. But the need for a tripod/mount assembly of telescope caliber just did me in – it was just too much hassle for me, despite the top class optics.
Let me list some negatives. Firstly, I do not like the eyecups– they are uncomfortable and too high, with the result that the image is vignetted (at least for my eyes); so I simply observe with the eyecups turned down. Secondly, the image seems to get a little blurred if the unit is not held steady – I believe that this is the consequence of the prisms moving around as they try to keep the image steady. Which leads to my final observation – I have never been able to achieve a truly stabilized image; while the ‘shakes’ are totally eliminated, in its place I get a gently oscillating image. A rock steady image can be achieved by adopting one of two techniques – either sitting on a chair with my head resting on the back, or by leaning against a vehicle, or a street light, or something similar. Now let me quickly add to any comments out there about how it is possible to get a steady image that way with regular binoculars - the magnification here is 15x, and I personally have never been able to use props as simple as those just stated to get a steady image at that magnification. And don’t forget that I am no spring chicken – I’m not as physically robust as I used to be as to when I once could hold 2 to 3 pounds perfectly steady for an extended period of time.
The positives outweigh the negatives by far – yes, I am really impressed. Firstly, let’s forget the stabilization for a moment and focus on the optics – they are crystal clear; as stated earlier, the objectives are made of ED glass and deliver very sharp images – at least as good as if not better than the Fujinon 7x50s. And the focusing mechanism is a dream – very smooth and very solid. The portability of this unit is its biggest asset, at least for me. I am now truly able to grab these binoculars at a moments notice, walk around with them hanging from my neck, and ‘just point and observe’ at random very quickly with no fuss – and get sharp images and high magnifications into the bargain!
The latter portion of this write-up is devoted to actual experiences with the Canons.
First light was just at midnight just as I got home from work. I grabbed the Canons and 10 seconds later I was looking at Jupiter - they did NOT reveal any surface markings, but the moons were just so obvious and were pin points, and there was a lot of dark space between them; I could very easily make out moons just a little less than half a Jupiter diameter away from the limb. And right next to Jupiter was the Beehive – the star images were again pinpoints, and the cluster filled up more than half the FOV through the binoculars. I was able to fit both the planet and the cluster in the same FOV. I was very impressed! Saturn showed some extension, but the true nature of the ring system totally eluded me. Next it was off to Vesta – and again the field stars were pin points and the multiple stars that were in the FOV were very easily resolved; and Vesta itself was effortless. This was fun! Next up was the Sombrereo Galaxy – it was just so easy to find the ‘triangle within a triangle’ on the star hop to the Sombrero, 3 of the 6 stars being resolved, as was 3 of the 6 stars of the ‘shark’ asterism; and while the Sombrero was not readily visible I did see a faint smudge at the location of the galaxy. I saw similar smudges where M81 & M82 should have been – and again the star hop to this pair was just so easy despite the 4.5 degree FOV. After about 15 minutes I put the binoculars down and went to bed – the ‘disassembly time’ was a few seconds! Now that’s ‘grab & go’!
The next evening - April 1st - I took them to work as I wanted to look for Mercury. I went out into the parking lot at dusk, walked around until I gained a good view of the western horizon, and immediately trained my gaze just above the horizon. With the naked eye I saw nothing. I then searched the horizon with the Canons but again I saw nothing except a plane’s lights blazing in the distance. But there was no sign of Mercury. After a few minutes I was beginning to get frustrated, then I suddenly noticed that the plane had not moved from its original position. Guess what – that ‘plane’ was actually Mercury. Naked eye, it was almost invisible but it looked so bright through the Canons! On the way back into the building, I took a quick peak at Orion; the views looked like I was staring at a page from Sky Atlas 2000 – the stars were just so vivid and clear. I must add though that the view of the Orion Nebula was disappointing – the views through the Fujinon 7x50s were better, I thought. Maybe it’s the 7 degree FOV that gives the Fujinons the edge over the Canons on this particular object; I can still remember Al Nagler’s statement that the most pleasing views are at the LOWEST magnification that still reveals the detail that you wish to see – I recall that it had something to do with framing your object against the background star fields.
The next morning was crystal clear so I decided to try the Canons on the Sun (caveat: never observe the Sun without proper filtration). I simply looked at the Sun through the mylar mask that I use for my telescope. I was able to see the penumbra of several spots, plage, limb darkening, and a hint of granulation – very sharp views. And using 2 eyes rather than one eye definitely gives the illusion of magnification higher than is being actually used. On a subsequent occasion, I saw no detail on the solar disk with the stabilization disengaged; but once I activated the stabilization, a pore - a tiny sun spot – jumped into view. The ‘shakes’ had hidden the pore from view. That night, I took a quick peek at a 12 day old Moon. The Moon was very sharp, but I was spoiled – I was disappointed at not being able to see Rupes Recta (the Straight Wall) ! But Clavius revealed its inner crater chain, Messiers A & B were resolved, Gassendi’s ‘Diamond Ring’ was just visible, and the ‘Snakes Head’ next to Aristarchus could almost be resolved, using some imagination. The views of both the Sun and the Moon were not too different from my 6” Dob operating at 25x. By the way, the light grasp of the Canons is the equivalent of a 70mm telescope.
Let’s talk about double stars. At 15x, the Canons should be able to split doubles as close as 20”. So one evening I spent about 5 minutes testing several double stars. First up was Iota Cancri (magnitudes 4 & 7, separation 30”). As expected, this was a real easy split, with plenty of dark space between the components. So I decided to go for something much closer – ADS 8505 in Virgo (magnitudes 6 & 6, separation 20”), closer to the theoretical resolving capability of 15x magnification; again, this was split without any difficulty – impressive. The only gripe that I had at this point was that the primary stars for each of the two targets tested so far exhibited some flaring, something that I have found common to all bright stars observed. I am not sure if this is an artifact of the image stabilizers, or the result of the fast optics (f/5 to f/6), or maybe just aberrations in my own eyes – if anyone has an opinion, please let me know. Anyway, back to the testing. The next subject was the toughest - Cor Caroli which, despite the 19” separation, consisted of very unequal magnitudes of 3 & 6. Double star enthusiasts know that resolving widely disparate magnitudes is much tougher than doubles of similar magnitudes. Well, once again the Canons made short work of Cor Caroli – yes, there was the flaring from the primary, but the faint companion was again obvious. This unit certainly passed the double star challenge! On a subsequent evening, I pushed them further than their capabilities – I could not split Rigel (magnitudes 0 & 7, separation 10”), nor could I split 31 Orionis (magnitudes 5 &10, separation 13”). However, I was seeing some elongation in the Trapezium (components D & C, magnitudes 5 & 6, separation 13”) so I would guess that the resolving capability would be around 15” for stars within 3 magnitudes of each other. This guess was made more credible on a later night when I was able to resolve Beta Scorpii 50% of the time, magnitudes 2.6 and 4.9, separation 13.6”; also that night v Scorpii (magnitudes 4.0 & 6.3) was absolutely effortless at a 41” separation – the black space between the components was massive.
In conclusion, these binoculars offer an incredibly convenient way to do some first class observing of objects that do not require high magnifications. The images are incredibly sharp, subject to the vagaries of the image stabilization system. I am most satisfied.