Canon 10x42 IS L Tripod vs hand-held vs IS testing (2 Viewers)

[typo]

Kimmo,

I have a Gurley, Troy NY version of the USAF 1951 chart given to me by a forum member that I used for this test. It's Group -2 to 4 and it looks just like the Edmund charts. I have home printed versions as well which are fine for longer distances that I have checked for accuracy.

I already knew from my time doing archery, occasionally my hands are much steadier than at other times. On those occasions I'll only be one or two patterns worse hand held. That didn't happen on any of the days of this test. No mystery. A 106/D is definitely a strange one though! Look forward to the explanation.

David

 

[henry link]

... While struggling with the hand-held readings, it occurred to me that more reliable results could be obtained if the patterns were not so tightly spaced. Now in very quick glimpses of elements 3&4 in a group in particular, with an unstable image and eyes flitting around in it trying to catch detail it is sometimes hard to be sure which element it was you were seeing. If you are more skilled at this or have a target with a wider spacing between the elements, that could explain why you have sometimes gotten better hand-held results even though our tripod results are almost identical.

Kimmo

This is exactly my objection to the 1951 USAF pattern for "naked eye" testing of binoculars, particularly hand held. Even tripod mounted I experience enough eyeball and head movement to make me distrust my impressions of the smallest resolvable elements. They're just too tiny and crammed together.

The NBS 1963A looks like it would be better, with longer lines and wider spacing of elements. You can see why I haven't bought one if you check the prices.

http://www.edmundoptics.com/testing...test-targets/nbs-1963a-resolution-target/1882

Henry

 

[kabsetz]

Henry,

This looks better than the USAF, and goes down to USAF equivalent 4,2. What I have is the #38257 2x2" USAF, that starts from 0,1 and goes down to group 7. It seems to cost 160 dollars today. It is worth it, though, especially with scopes, since the lines are razor sharp and consistent, and contrast with good back-illumination ridiculously high. I don't think I'll splurge for a second slide, but I'm glad I god the first one.

Kimmo

 

[kabsetz]

I re-tested the Ultravid 8x20 now. Not fussing with absolute limits, rather attempting to be even more careful and conservative than usual. Essentially, this duplicated the earlier results.

First, I re-measured the distances to the target, and reassuringly found my reference points to be accurate. We can estimate a margin of error of less than +-2 cm for the reference points and perhaps +-5 cm for how well the tested binocular's objective lens is placed with reference to the reference points. All in all, at these distances, it leaves a margin of error of only about 1% for the distance to target variable.

Henry and David, you can check the math, but this time, with a 3x12 Zeiss booster behind the Leica eyepiece and distance to target being 10.30 meters, I very easily resolved group 1 element 5, and resolved group 1 element 6 convincingly (I was convinced). Of these, in 1/5 spaces between lines could be detected, in 1/6 line orientation was certain, but contrast between lines quite low.

Please comment.

Kimmo

 

[henry link]

Kimmo,

The measurements in your last paragraph look like 5.625" and 112.5/D, still extraordinary for any telescope. I have occasionally thought that I saw resolution almost that good on the USAF 2x2" slide when using my A-P Stowaway or Tak FC-50 as reference scopes. In those cases the target distances were longer and I assumed there must be some error in my measurement of the distance.

I can only suggest a couple of explanations for your experience with the Ultravids, partial at best. One is that 24x may be the absolute best magnification sweet spot for resolving line pairs in a 20mm scope like the Ultravid. The other is related to your pupil size for best acuity. In a discussion here about acuity and pupil size maybe 8 years ago I recall Jean-Charles Bouget referring to a study that found quite a surprisingly large range in pupil size for diffraction limited acuity, even (I think) going up to as large as 4mm or more in a few individuals. Perhaps your diffraction limited pupil size really is 3mm or even larger.

Henry

 

[typo]

Kimmo,

To summarise the two results, you found 106/D yesterday and 112.5/D with the revised distance today. For point sources the Sparrow limit or zero separation is 107/D and what is normally regarded as the limit for the eye, the Dawes limit is 116/D. Sorry I don't know how it's possible for you to see contrast between the lines at all for 1,6 at 10.3 or 10.9 meters.

David

 

[henry link]

David,

Line pairs are more easily resolved than point sources. I expect to see about 115/D from 1/8 wave or better optics on the USAF chart. I think that represents about 3% contrast between bars and spaces.

Henry

 

[Binastro]

. Lines are not dots and they are not stars.

I have a smiley face about 3.5 m from me, which I drew with a very thin line.
Not only can I see it with the light on in my room, I can see it fairly easily with the lights off and only dim lighting from the hall.
I can see the outer circle, the two eyes, and the mouth.
Each element of the line, or the width of the line, is totally unresolvable to my eyes.

The Crescent of the planet Venus and the elongation of Saturn's outline has been seen consistently by some people who have exceptional eyesight.
There are also quite a few cases of people seeing Jupiter's moons with unaided eyes, often by children.
It may be that some of these children have the best resolution at 4 mm, I don't know.

If Kimmo gets the results that he does I'm very comfortable with that.

 

[henry link]

Binastro,

Detection of a single line or point source is much much easier than resolving pairs of lines or points (or dots).

Henry

 

[typo]

This may be a slightly crazy idea. That lamp Kimmo uses to back light the slide is very bright. I suppose it's a fluorescent tube design and therefore an incoherent light source but I might be wrong. I cut a couple of parallel slits in aluminium foil about 1mm apart and backlit it with a 60 lumen LED torch at a range of about 4" which gives me about 15000 lux on my light meter. When I viewed it (while squinting) from 3m I could see a interference pattern of multiple lines of varying intensity, but very clearly exaggerating the orientation. Might it be possible that something similar was happening for the 1,6 pattern?

David

 

[Binastro]

Thanks for that Henry.

 

[kabsetz]

David,

I don't think anything that weird is happening. The image looks exactly like what an excellent-quality resolution target should look like, when viewed with really good optics with diffraction limiting their performance. The only anomaly is that according to conventional optics wisdom it should cut off at 1,4 rather than 1,5 or 1,6.

I think Henry's explanation about the setup hitting the sweet spot of what is anyway an excellent binocular is the most likely one. The exit pupil at 24x would be 0.83 mm, which is about optimum, the target is perfect as far as targets go, and light levels can be optimized & there is no glare to mess things up.

It just may be that one can detect line pattern orientation further than we have thought. Also, when I tested the ATX 95 with the same setup, I got to about 116/D but may have had the light intensity too high and/or the exit pupil too small. I'll need to test that scope with 110-120 magnification to see what happens.

Kimmo

 

[Binastro]

I used to be a regular observer for many years of the planet Saturn and also of Jupiter.
Mainly using a custom 12.5 inch F/14.7 compound scope and also with normal Newtonians I was always able to see more linear detail by tilting my head sideways by about 90°.

I think that the reason was probably that I have a small amount of astigmatism, which was fairly constant in those days.

It seems that Kimmo has almost perfect eyesight and I don't suppose he has any astigmatism.
But if somebody has very good eyesight with some astigmatism, would they be able to resolve line pairs on a test chart better in one direction than the other, and might they be able to exceed what is normally considered a limiting resolution.

Personally, I don't like test charts, but that is not the issue here.

 

[Torchepot]

Thanks Kimmo,

One of the most interesting threads I've ever read. The implications of your test results are huge (at least for me). I will definitely be trying our the 10x42 IS very soon. First I'm going to test my own current bins Swaro 10x42EL and Leica 8x32 BA on a downloaded resolution chart to gauge my own ability to hold them still. I'll check against tripod mounted results and try at two different distances. I'm not trying to actually measure the resolution just hoping that I'm one of the lucky few with a grip like iron man who may not benefit much from IS.

I've never seen Canon IS bins in the field and I don't know anyone who has tried them. This low profile is also reflected in the dealers who stock them in the UK - my favourite - Lakeside Optics at Chew Valley Lake near Bristol don't have them and I've yet to find a stockist who have a viewing environment other than the street outside their shop.

Thanks again

Phil

 

[etudiant]

I've never seen Canon IS bins in the field and I don't know anyone who has tried them. This low profile is also reflected in the dealers who stock them in the UK - my favourite - Lakeside Optics at Chew Valley Lake near Bristol don't have them and I've yet to find a stockist who have a viewing environment other than the street outside their shop.

Thanks again

Phil

Hi Phil,

Canons are indeed rare in the field, I've seen four apart from my own in ten years here in NYC, even though in Central Park the birders often outnumber the birds.
Nevertheless, the 10x42ISL is what Kimmo describes, a superior piece of kit.
It is heavy, you'll want to carry it on a harness or a bandoleer strap, bulky and has eye pieces designed to fit flat faces or people wearing glasses, but it gives bright and sharp views across a good field, with decent eye relief. It is unequaled for observing birds in flight or picking out differences.
Dealers for it are few, so I bought mine on Amazon. That gave me plenty of time to get comfortable before the return window expired.

 

[Torchepot]

Thanks Etudiant,

Great to hear from someone who actually uses these elusive beasts! I've owned quite a bit of Canon equipment over the years and still have a dslr and sx60 right now. Maybe I've been lucky but I've never had any trouble with any of their gear. The sx60 has some design issues but for my purposes it's proving to be a great little camera.

I find it surprising that a binocular which may have a 30 percent advantage in resolution over handheld non-stabilized instruments attracts so little attention. If one of the leading manufacturers produced a binocular with even a fraction of that advantage there would be a huge commotion. I know that the extra weight may be an issue for some but by chance I usually wear my bins over one shoulder so it's probably not going to be such a problem for me.
I'm also happy to try out a harness as I seem to be in the field a lot more these days. The warranty issue is a problem but I may try to find if there is some kind of insurance that could help - if I'm truly smitten!
All of the other bins that I'm interested in are more expensive, the Zeiss 10x42 sf are around twice the lowest price I can find for the Canons so there is room to beef up insurance and still come out ahead. Probably won't get a chance to try them out for a few weeks so in the meantime I'm inspired by Kimmo to test my current bins against each other.

All the best,

Phil

 

[etudiant]

All of the other bins that I'm interested in are more expensive, the Zeiss 10x42 sf are around twice the lowest price I can find for the Canons so there is room to beef up insurance and still come out ahead. Probably won't get a chance to try them out for a few weeks so in the meantime I'm inspired by Kimmo to test my current bins against each other.

All the best,

Phil

The short guarantee seems to be the biggest issue for other contributors here on BF. While the term is in line with other Canon digital gear, it falls way short of the Swaro or Zeiss decade or life long level. Plus there have been a couple of BF posters who had repair quotes on their Canons that were maybe half the purchase price, so if it fails, it is very dear.
My own experience since 2008 with my 10x42 has been exemplary, Panama, Peru, Iceland, Alaska, the glass has not missed a beat. Sancho is afaik the only other BF member who has owned several of the Canons, he may have additional insight on reliability across the models.
All considered, I'm skeptical of the value of insurance for these, the initial warranty covers infant mortality and current electronics are pretty durable.
The real concern would be that no one could repair these competently, other than the factory, so even with insurance the repair might be iffy. As you noted, the 10x42 sells for half the price of the Zeiss or Swaro, maybe put that money into a Swiss Frank annuity, there should be enough left for a down payment by the time your first glass expires.

 

[Torchepot]

That's a pretty good endorsement, and my experience of Canon gear in some rather hostile environments has been faultless too. At some point I guess you just have to weigh up the pros and cons and go for it. If the improvement in resolution is even half as much as it appears then that's a pretty big plus!

I wish I'd put my money into Swiss Francs last week - they just went ballistic!

 

[Binastro]

. Over the last 15 years or so I has owned every Canon image stabilised binocular model, except the first 15×45. However, I think that there have been some changes in the stabilising method in some models, the details of which I am not aware. They also are variable in quality, apparently, although all of mine have been excellent except the one that I bought second-hand. I think that in general the stabilising may have improved over the years but not always the optical quality.
I have mainly used them for astronomy and they have not had a harsh life, such as they would be subjected to by birdwatchers in the field.
There are issues with them, and from the money point of view, the one-year warranty is problematic.
Personally, I believe that the advantage, particularly in resolution over standard binoculars in average conditions is considerably more than 30%, especially if you are following some object. Most models are not as bright as standard binoculars, especially because of the small exit pupil.
They are heavier and bulkier than the equivalent standard binocular.
I'm also surprised that more birdwatchers don't use the 10×42, but birdwatchers seem to be a conservative bunch.

I definitely would not buy a second-hand Canon image stabilised binocular.
The non-waterproof versions are quite likely to have suffered from internal moisture.
The binoculars are complex, so that is also an issue, but so are cameras.

So long as you can try them before purchase, I think they would be very good. Or at least have a period where you can return them.

I have normally insisted that the supplier takes the brand-new binocular out-of-the-box and tests them for collimation and quality. In fact I do this with any binoculari that I buy remotely. In addition, I ask the supplier to pack the binocular very well. These additional steps increase the likelihood of having a binocular with no problems, but it is not 100% foolproof.
If you buy binoculars second-hand from members of the public they often don't have a clue about collimation or haze even if you explain it carefully.

 

[Torchepot]

First stab at comparative test

Impatient to try my current 8x32 Leica BA against my 10x42 Swaro EL and not able to get my hands on a resolution chart yet (I'm on holiday in Spain and have no printer) I tried to set up a simple test. I fixed a magazine page of adverts with many different fonts and print sizes 11m away at head height outdoors in overcast but bright conditions. I tripod mounted each binocular in turn and looked at how easy it was to read the smallest print. As expected the 10s were the easy winners - but what was a surprise was the amount of head movement I experienced. I've never tried binoculars on a tripod before, though I've been using scopes for years and am currently using my Nikon ED82 pretty much every day. Maybe it's because I'm not used to the set-up with tripod mounted bins but it was very noticeable that despite the bins being "locked-off" I was still getting some degree of movement because I was unable to stop slight head movement. I could eliminate most of this by resting my brows on the eye-cups but thought this might affect the steadiness. I asked my wife to try and she had exactly the same result - which was a relief as I thought I might have suddenly acquired a tremor!
Strange cos when I use the scope I just stick it on the tripod and look through it without ever noticing any head movement - though people who are unused to using a scope often have trouble keeping their head still.
Anyway we both then tried to read the smallest print using each binocular by hand and were pretty disappointed by the 8s to the point where my wife gave up trying and said she'd never realised how poor they were.
Finally I fixed up a page of plain text and found the maximum distance at which I could read it out loud at normal reading speed without making mistakes - 10.5 metres using the 10s then tried the 8s from the same distance - I couldn't read it at all - maybe guess at the odd word. I should have then moved forward to find the "comfortable" reading distance for the 8s so that I could give a percentage figure to the difference but I forgot to do it. It's an easy set-up though so may have another go tomorrow and also check out the amount of head movement I get with the scope (though I've never noticed any). So fairly conclusive for us with these particular bins the 10s come out on top in terms of resolving detail. I want to repeat this test now with one of my friends Swaro 8x32SV against my 10s.