Everything you always wanted to know about IS binoculars but were afraid to ask (Q&A) (1 Viewer)

[yarrellii]

Throw in your questions! And your answers!

Over the last weeks I’ve started using IS binoculars and I’m discovering things I’ve read about but also encountering things I didn’t know or just hadn’t stop to think about. Ok, so IS binoculars are binoculars (Nobel prize speaking here), and are supposed to work more or less like any other binoculars: light goes through a series of lenses and prisms and it's magnified before getting to your eyes. However, I think they have some quirks or considerations that many times remain unknown for people who have never used them. All in all I think IS binoculars are not very popular or well known amongst the general public (and birders seem no exception). Maybe I’m speaking just for myself, but my feeling is that there are many doubts and aspects about IS binoculars that remain unanswered.

So I’m opening this thread with the idea of making it a cooperative/joint effort to clear the doubts that many people who have never used IS binoculars might have. Since I have near to 0 experience in the subject, I'm just the one to set the ball rolling, but I hope that seasoned IS users can give their insights, opinions and experience to answer the many questions that people who have never used IS binoculars might have.

Here are some questions that came to my mind, but please don’t be shy and add your doubts and questions, even if they may seem simplistic or daft (you never know who might share your doubts). Hopefully we can gather in a single thread a wealth of knowledge about IS binoculars in order to help other forum members.

• How long do batteries last?
• Can you use rechargeable batteries? And if so, does it make any difference?
• Do IS-binoculars suffer from a loss in image quality when IS is on? (compared to when it’s not)
• Do IS binoculars always suffer from strange artifacts on the image?
• Can you pan with IS on? (like when following a bird in flight)
• Does IS improve low-light performance? (like the capacity to see detail at dusk)
• What’s the response time of IS once you press the button?
• In some IS models you have to keep pressing the IS button 100 % of the time in order for it to work, does this pose a stress on the mechanics and make it more prone to failure?
• Does it make any difference to store your IS binoculars laying flat or standing?
• Is there any further maintenance to be done besides conventional cleaning of the lenses?
• Since most IS binoculars have no central hinge and the main optical train is hidden in a box, are IS binoculars less likely to get out of collimation/alignment if knocked?
• Are there wide angle IS binoculars or do they generally have a modest FOV?
• What’s the lightest/most compact IS?
• What's the highest IS magnification to be hand-holdable?
• Are there noticeable differences in the IS technology used? The same way, for example, that a user might experience a difference in depth and 3-D effect when using Porros or roofs.
• What’s the “life expectancy” of IS binoculars? Do they last as long as quality conventional binoculars?

... (your questions here) (and your answers too, please!)


As a background, here are other threads regarding IS binoculars on BirdForum:
Is IS for the Birds?

IS binoculars or scope for higher magnification

Canon IS Binoculars

Durability of Canon IS binoculars

IS binoculars, the battery issue

 

[Binastro]

A bit at a time.

Battery life varies with model and age.
Some can use rechargeable batteries, some can't.
Some can use lithium batteries some can't.
Image quality can degrade with IS on, but this varies with the skill of the user particularly.
It depends on speed of panning and model and make.

I had intended starting a thread asking whether resolution of the eye when panning without optical aid and with binoculars, standard and IS had been researched.
But never got round to this.
This is a complex subject.

Some IS binoculars have strange artifacts with IS on. This varies.

IS probably does improve low light level performance.
However, comet visibility etc. can benefit from movement of the image.

Response time varies with model.

Pressing button etc. question. I don't know.

With some IS binoculars I think storing flat is best. Storing vertical worse.

Maintenance clearly more with IS binoculars, but not user dependent, unless making sure battery contacts don't degrade.

They may or may not hold collimation better, but the complex mechanism might be damaged.
I wouldn't want to drop the Zeiss 20x60S.

The Canon 18x50 IS has a field of 3.85 degrees or 69 degrees simple AFOV.

I don't know what the most compact IS binocular is.

Zeiss 20x60S or Russian 20x, 25x.
Higher magnification IS binoculars would be hand holdable, but so far as I know not made.
I think 35x possible.
I tried 18x50 IS with 2x and 2.5x boosters but image quality awful.

There are many different technologies, and makers changes that are not announced.
The perception of the user maybe an unknown.

IS binoculars don't last as long as quality non IS binoculars.
But some are surprisingly inexpensive in comparison.

Regards,
B.

 

[Maljunulo]

They are truly excellent and they bring incredible value for the price. I find them very sharp and with surprisingly low CA. I am not going to sell them, the reason I’m asking for help here is because my wife (whom loves these lightweight binos and don’t struggle with blackouts) will keep them and I need to buy a new pair for my self.

IS probably does improve low light level performance.

How?

 

[Binastro]

The same way a tripod mounted binocular improves low light level visibility.

Regards,
B.

 

[Maljunulo]

Okay.

 

[dries1]

I have used IS binoculars, civilian and military, my complaint on both was bulk. On a boat or helicopter for surveillance it has its use. In Astro only the Canon 10X42 was decent in use (under a dark sky), but when the magnification went up 15x50 18X50, the bulk comes into play. I thought the IS in the 10X42 performed the best. Sample variation, perhaps on the larger magnification glass could have been the factor.
I have only tried the 20X60 Zeiss once, but the FOV to me was ehhh...constricting. I use a Nikon 18X70 short sessions hand held, or mounted instead.
If I were to invest in an IS now it would be the Canon 10X42, the least bulky and most proven model.
I cannot see an IS lasting as long as a premium conventional glass, if used daily in the woods/hiking etc.. As an alternative piece of equipment for occasional use, it is very suitable.
Just my opinion.

 

[Maljunulo]

I remain unconvinced.

 

[jring]

In Astro only the Canon 10X42 was decent in use (under a dark sky), but when the magnification went up 15x50 18X50, the bulk comes into play. I thought the IS in the 10X42 performed the best. Sample variation, perhaps on the larger magnification glass could have been the factor.

Hi,

I would blame it on sample variation, as the 15x50 weights just 100g more than the 10x42 - 1.2kg vs 1.1... and is not a lot larger either... 1.5 cm more in length and width, about the same in the smallest dimension...

Optically the 15x is probably the second best after the 10x42.

Joachim

 

[Sebzwo]

For me a big part of the fascination of binoculars is the "pure optics - no battery" part. I am totally respecting the fact that smart, stabilised binoculars might be more usable in certain situations but I prefer to not have to worry about batteries and maybe even have to carry spare ones. I have a cable mouse, a mechanical bicycle and like it this way.
I have 7x and 10x binoculars that are usable without tripods. Some lower magnification might do the trick as well.

 

[Binastro]

Apparently the gimbal mount was in use in China 2,100 years ago.

I would think that military sights had some sort of stabilizer in tanks and aircraft before 1920.

Stand alone optical stabilizers were tried perhaps in the 1960s.

By about 1980 there was a British IS monocular, possibly also a binocular.

1990 Zeiss had the 20x60S.

Perhaps 1997 the Canon IS binocular.

There are probably twenty different types of IS in binoculars.

The Steadicam movie stabilizer dates from 1975, but I think giro platforms were used before this.

With consumer cameras there are countless stabilizers.

Tripods are stabilizers also. Monopods less so.

Regards,
B.

 

[edwincjones]

many disadvantages but the main advantage of IS is being able to handhold higher mag binoculars with a steadier image

edj

 

[etudiant]

many disadvantages but the main advantage of IS is being able to handhold higher mag binoculars with a steadier image

edj

Think that is really quite wrong, the gain from IS is that you can focus on the bird, rather than the jitter.
It makes a huge difference when looking at warblers in the treetops, suddenly the image is still, just the bird hopping around..
Also true for birds in flight, seabirds at a distance, etc.

 

[edwincjones]

Think that is really quite wrong, the gain from IS is that you can focus on the bird, rather than the jitter.
It makes a huge difference when looking at warblers in the treetops, suddenly the image is still, just the bird hopping around..
Also true for birds in flight, seabirds at a distance, etc.

are we not saying the same thing?

edj

 

[etudiant]

are we not saying the same thing?

edj

Imho the point is that the magnification, higher or lower, hardly matters. The IS really freezes the background, so one can focus on the moving bird.
It is seriously habit forming, I reach for the non existent IS button on my old Zeiss 8x30 Classics when on a casual birding stroll.

 

[CSG]

I've had a pair of Canon IS 10x30's for years now and while many other bins have better optics, these are truly amazing, especially for astronomy.

 

[edwincjones]

Imho the point is that the magnification, higher or lower, hardly matters. The IS really freezes the background, so one can focus on the moving bird.
..................

thanks- I have never noticed that I have never noticed this.

edj

 

[Hans Weigum]

Apparently the gimbal mount was in use in China 2,100 years ago.

I would think that military sights had some sort of stabilizer in tanks and aircraft before 1920.

Stand alone optical stabilizers were tried perhaps in the 1960s.

By about 1980 there was a British IS monocular, possibly also a binocular.

1990 Zeiss had the 20x60S.

Perhaps 1997 the Canon IS binocular.

There are probably twenty different types of IS in binoculars.

The Steadicam movie stabilizer dates from 1975, but I think giro platforms were used before this.

With consumer cameras there are countless stabilizers.

Tripods are stabilizers also. Monopods less so.

Regards,
B.

Systematischer Inventar IS-Ferngläser, überarbeitet

HW

 

[Viraj]

I recently bought a 12x36 IS III. Still it couldn't convince me to keep or send it back because of 2 main reasons. The CA is very prominent to my eyes however the major concern is the lack of waterproofing. Can anyone tell me how do you take care of your binoculars? I afraid of getting mold inside as I had a bad experience many years back.

 

[Jon555]

I'll have a go, but I can only talk about my 10x30 IS, which are a discontinued model...

• How long do batteries last?
  I find they last a considerable time, but then I've not looked through them for hours on end.
• Can you use rechargeable batteries? And if so, does it make any difference?
  Yes, I use Eneloops. Since battery life is good it's impossible to compare with Alkalines as they both seem to last a long time
• Do IS-binoculars suffer from a loss in image quality when IS is on? (compared to when it’s not)
  Mine don't
• Do IS binoculars always suffer from strange artifacts on the image?
  No
• Can you pan with IS on? (like when following a bird in flight)
  Yes, smoothly
• Does IS improve low-light performance? (like the capacity to see detail at dusk)
  Very much for stuff like stars, (pause to experiment as it's dusk) yes for everything as it keeps it at the same position in your eye
• What’s the response time of IS once you press the button?
  Maybe 1.5 secs
• In some IS models you have to keep pressing the IS button 100 % of the time in order for it to work, does this pose a stress on the mechanics and make it more prone to failure?
  Mine require that and are over 22 years old and going fine
• Does it make any difference to store your IS binoculars laying flat or standing?
  No idea, not stood them on their objective lenses as the case wouldn't allow that, just bottom or side.
• Is there any further maintenance to be done besides conventional cleaning of the lenses?
  Not unless something goes wrong
• Since most IS binoculars have no central hinge and the main optical train is hidden in a box, are IS binoculars less likely to get out of collimation/alignment if knocked?
  I don't know, sorry
• Are there wide angle IS binoculars or do they generally have a modest FOV?
  I'd have to run through the specs. The tend to have a good apparent FoV, plus some models have field flatteners (e.g. mine) which helps with the flatness and sharpness towards the edge of the field. (I think you should get those in other companies' higher-end binoculars.) Mine are 6° FoV which sits between the 5.5°of the older Zeiss Conquest 10x30s and the 6.2° of the Swarovski CL Companion 10x30, the Nikon Monarch HG 10x30's are 6.9°.
• What’s the lightest/most compact IS?
  Not quite sure what you mean, as you don't tend to to get a choice of IS at the same X x Y binoculars, so the smaller the X and Y the smaller/lighter the binocular (so 8x20 for the win).
• What's the highest IS magnification to be hand-holdable?
  18 x 50, except they are heavy so the issue isn't getting a stable view, but how long you want to hold them.
• Are there noticeable differences in the IS technology used? The same way, for example, that a user might experience a difference in depth and 3-D effect when using Porros or roofs.
  Yes, considerably. Canon probably have 3-4 different systems, some are just improvements on earlier ones. Apparently the latest x32 bins have a very great degree of stabilisation. I'm not sure it matters hugely as mine are fine by me and it's the original system.
• What’s the “life expectancy” of IS binoculars? Do they last as long as quality conventional binoculars?
  I had the focusing knob get a bit sticky after 18 years (bought and fitted a replacement one) and the Glue holding the bits inside the battery compartment lid give up at 22 years (stuck them back in).

 

[Binastro]

IS binoculars should be stored horizontally not vertically in general.

Some IS binoculars may not like lithium AAs or Eneloops.
There were a few Canon IS where black Eneloops were too thick.

Zeiss 20x60S easily hand held but heavy, bulky and not easy to use.

Possible 25x56 Russian?
Also 20x50.

Regards,
B.