Question re: magnification (scope v camera)

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Maybe an odd one, maybe a "dumb" tech question. 

I asked last September about monoculars and got some helpful answers

In the end I managed to borrow some 12 * 50 Nikon binoculars for that trip, and the monocular idea was put on a back burner. 

Now I want one again. Purpose - something reasonably pocketable, to take on walks and have a closer look at (for example) wildlife e.g. some grey geese that seem to almost enjoy a bit of aerobatics over a field; also architectural details if I am wandering a nice pretty historical city like Florence (also inside cathedrals - even a recent visit to the Natural History Museum would have been fun with a little monocular). 

I am considering either a 10*50 Barr * Stroud Sprite which I can get new for around £52, or a Minox 8 * 42 CWP second hand for around £40 which seems a big discount. 

But just to get some idea of what to expect, I just went for a short walk with my Canon EOS600D and a cheap 55-200mm zoom mounted. I believe this gives an equivalent of a 6x magnification. I used it to look at swans and ducks on the canal.....and the experience was really underwhelming, almost like there was no point. 

So the question is, for a given magnification, is the perceived image through binoculars/monoculars etc a lot more "exciting" than in the small viewfinder of a camera?

I remember the binoculars that I borrowed, being really effective (of course 12x is a big difference to 6x). 

I am just wondering whether I should go for a zoom monocular; there is a 10-25 x 42 seemingly getting good reviews. I understand all the issues with stability at longer zoom; I could live with using a tripod mount for longer zooming if required. 

Or is there something about the brightness and sharpness (or something else) on a half decent monocular, and the size of eyepiece, that makes the comparison to a dSLR irrelevant? 

Thanks in advance. 

 Tom Valentine 26 May 2020

.In reply to Blue Straggler:

Same point as I made last time; for some reason monoculars are hard to hold.

I converted a cheap trekking pole to a monopod - quite effective, especially if you add a tiny ball mount and steady enough for a 20 X Barr and Stroud and 9-27X  Hummingbird.

 Marek 26 May 2020
In reply to Blue Straggler:

The comparison is not irrelevant, but it is complicated.

For example, I have 8x binoculars and an MFT camera with a 100-400mm lens. The bins are great for scanning around and spotting something interesting, but when it comes to actually identifying a bird a photo will reveal far more detail than you can see through the bins. Particularly with flying birds or fleeting glimpses between tree or reeds. The bottom line is that they both have their uses - I wouldn't want to give up either.

But then that camera/lens combination is effectively ~3x longer than your 600d@200mm, so perhaps an unfair comparison. I also have a 6d with a brilliant 70-200 lens and frankly I wouldn't bother getting it out  of the bag for a bird unless it was very close (max 3-4m?).

Hope that gives you at least a couple of data points if not an answer.

 swalk 26 May 2020
In reply to Blue Straggler:

Binoculars will give you a more satisfying view than a monocular (twice as good) but are bulkier and heavier. High magnification will give more detail at the cost of a narrower field of view (width) and depth of view (front to back). The best compromise is a magnification of 8 x or 10 x; more magnification gives a narrow view (shakes) and harder to focus. The other number (8x40 - the 40) relates to the width of the light gathering lens in mm - bigger lens gives you a brighter image at the cost of greater weight and bulk. Best compromise usually 25 to 50mm. Especially for cheaper binoculars, Porro prism types have a better optical quality than Roof prism.

Zoom binoculars are best avoided because the optical quality is poorer with additional weight and fragility.

For the price and your use, hard to beat Bushnell Powerview 8x25 Porro Binocular (£44 Amazon). If you wear glasses consider the eye relief.

But you get what you pay for - like your camera and its lens - and if you can stretch to a medium quality binocular you have something that will last 20 years. Unlike cameras, binoculars have not changed greatly in 30 years and improvements have been incremental.

For "quality" binocular reviews see the "Binocular" section in

In reply to all so far:

Thanks. My 55-200mm lens on my camera is certainly not something I am “proud” of, I know it is crappy but it was £20 in a charity shop and has effectively paid for itself in terms of a few shots I am happy with. 

I don’t want binoculars right now, this is why I am looking at monoculars. It’s a risk that might not work out, and a risk I am happy to take. I can always resell.

As mentioned in OP I do sort of understand the fundamentals. The big number is brightness, larger magnification is harder t hold steady etc.

Nobody has quite answered the question from the OP yet which leads me to think there isn’t really a difference and I should take the gamble on a zoom monocular (knowing that £ for £ and gram for gram, it will be a bit of compromise ) 

In reply to Blue Straggler:

> But just to get some idea of what to expect, I just went for a short walk with my Canon EOS600D and a cheap 55-200mm zoom mounted. I believe this gives an equivalent of a 6x magnification. I used it to look at swans and ducks on the canal.....and the experience was really underwhelming, almost like there was no point. 

Did you try actually taking a photo and then looking at it in the back of the camera (or, better, electronic viewfinder if you have one) fully cropped? I find I can see birds and so on kin great detail like this.

In reply to Robert Durran:

Hi Robert, thanks for the suggestion but that’s not quite what I was getting at. I am happy enough (actual lens quality notwithstanding) with viewing PHOTOGRAPHS taken at 200mm on my cheap zoom, but the question is about “live” view through a monocular. Sorry if that wasn’t totally clear in the OP; it’s a bit hard to express clearly 

 Frank R. 27 May 2020
In reply to Blue Straggler:

As I remember, the very broad rule of thumb for comparing magnification went something like that: a 50mm lens (around the "normal" length on 35mm film) was like 1x, so your 200mm would be like 4x? Of course, that does not take into account wide or narrow field of view of different binoculars, it was just a quick'n'dirty comparison. Which is nowadays somewhat invalidated further because you can just zoom into the digital photo on the LCD (but with all the added difficulty of seeing anything on an LCD in the sun outside).

And yes, having shot photos with massive lenses like 600mm f/4 and cameras with good viewfinders, I still find the real view through good quality 12x binos (I got just some old Soviet military ones, but they were pretty good when stabilised on something!) was definitely "more exciting". Until you zoom in into the detail on your computer at home, than it's a different matter

 Tom Valentine 27 May 2020
In reply to Frank R.:

Doubly confusing with camera makers claiming excessive zoom lengths.

The figure is based on the widest zoom setting so the claimed 60X zoom on my Lumix FZ  is based on a 20 mm bottom end  so if the 50 mm standard is right my zoom is actually 24x at maximum (optical). Still a fun camera!

As to the 50 mm idea I remember a lot of discussions about this in AP magazine  and a big faction favoured 35 mm as the standard eye view .....

In reply to Tom Valentine:

50mm on a 35mm camera represents the field of view you get with one eye closed. 35mm focal length on a 35mm represents the field of useable vision (ignoring the periphery where you only sense movement and high contrast but not accurate shapes etc) with both eyes open which is why it became a very popular focal length when mass market cheap cameras became popular 

In reply to Frank R.:

Thanks, yes 200mm is like 4x on a 35mm or so called “full frame” digital sensor. I have a so called “crop sensor” which makes it more like 6x

I have decided to buy the second hand 8x42 Minox if it is still available

Thanks for all input 

 Frank R. 27 May 2020
In reply to Blue Straggler:

Hope you like them! As I wrote, my last and now only binos are the old Soviet ones, which are not exactly "lightweight" or "small" at all  

I would love some recommendation for a small good quality mono (not costing as much as some photo lenses) that's light enough to just take on the hill walks or scrambles. But the specialised forums are just way too much over my head... I was watching the older thread with interest as well.

BTW, are there any smaller stabilised monoculars? In the 8-10x range? Does the IS tech work even when the battery runs out? Although that might be quite a lot more expensive?

Post edited at 22:45
In reply to Frank R.:

I didn’t even think to look for image stabilisation, then I was looking for cheap and cheerful sub-£80 things 

I never felt I needed it when I was using a borrowed pair of 12 x 50 Nikon binoculars on my trip around Canada and USA last September (looking up at mountains from roadside, and on a whale watching trip). Those were £300 binoculars and didn’t have IS 

 Adam Long 30 May 2020
In reply to Blue Straggler:

> So the question is, for a given magnification, is the perceived image through binoculars/monoculars etc a lot more "exciting" than in the small viewfinder of a camera?

Short answer is yes.

Long answer is binos/ scopes project the image directly onto your retina. SLRs project the image onto a focusing screen, which you then view via the viewfinder. For starters this cuts down the brightness due to extra optics and the ground glass screen introduces a granularity to the view (and usually distracting focusing aids etc). And on a cheap DSLR like a 600d the viewfinder is one of the places corners are cut, as viewfinders require precisely aligned physical optics and the relevant specs never make the headlines and are often obfuscated anyway. But if you get the chance compare the viewfinder of your 600d with a pro slr like a EOS 1 or  Nikon D3 (or a classic like an OM1) - there'll be a big difference. But even then the angular field of view of the focusing screen presented to your eye will be maybe 2/3 rds of an ocular by angle  - a60 deg circle vs 40 deg diagonal of a rectangle (and therefore about 1/3 by area) and appears to be at 1-2m away - like looking at a poster. Whereas you look through an ocular with the eye focused at infinity.

Then with binoculars you get the benefits of binocular summation - two eyes feed into one mental image. Creates 3-d depth perception with improvements in comfort, brightness, resolution, contrast, stabilisation and gets rids of artefacts like eye floaters. I've never owned a monocular but have three telescopes. Mono-viewing is better suited to tripods imo and two eyes are three times as good if they're available.

One of the biggest benefits of good bins is viewing comfort - not something that can make it into specs but cheap bins generally fatigue your eyes rapidly, and are prone to losing collimation if knocked.

Caveat is, with a high res modern camera and decent lens >300mm equiv, you might see a bit more detail than 8x bins if you take a quick shot then zoom in to 100% on screen. Especially if the bird has flown off...

But if I was to be given a conversation with my younger self one of the pieces of advice I'd give would be to spend a lot less money on lenses and a lot more on optics. My most expensive prime lens was twice the cost of my best bins and can't get more than 0.3% of the use, and I frequently don't like the photo whereas I've never not liked the view through the bins. 

In reply to Adam Long:

Fantastic reply Adam, thanks for taking the time. Well I await delivery of this second hand Minox, hope it’s in good nick etc

In reply to Blue Straggler:

Update on this, after a rather long wait (possibly due to being a cheapskate and getting second-class recorded delivery instead of first-class; think the difference was marginal too!) my second-hand Minox 8 - 42C WP monocular arrived today and I took it out on a walk. It's great. See Adam Long's post that addresses the questions in my OP. 
It's a bit bigger than I expected but will sit reasonably in a trouser pocket as long as there is nothing else in there. 
I find it fairly easy to focus quickly and, considering it was my first time out with it, I was pleased with tracking a couple of distant birds in flight, and a train. 
It's also nice "close up", I was able to stand a safe distance from a lone adolescent moorhen (I guess that is what it was) just dipping toes and beak into water; it filled the frame and the sharpness was great. 

I fashioned a tether or lanyard just from a bit of old tent guy rope and an accessory carabiner to clip to a belt loop and hold taut as the monocular is at eye level, to increase stability (I used to do with lower-end compact digital cameras in low light, quite effectively), but as I haven't really tried without this, I don't know if it was necessary. Enjoyed a random and unplanned test, reading gravestone inscriptions. 

It is my new toy for today so the novelty MAY wear off, we shall see. 

 aln 08 Jun 2020
In reply to Blue Straggler:

> It's a bit bigger than I expected but will sit reasonably in a trouser pocket


In reply to aln:

> > It's a bit bigger than I expected but will sit reasonably in a trouser pocket

> Boasting? 

Is that a second-hand Minox 8 - 42C WP monocular, or are you pleased to see me?

 Adam Long 29 Jun 2020
In reply to Blue Straggler:

>Then with binoculars you get the benefits of binocular summation

Just a little addendum to this - viewing with two eyes actually creates an illusion of greater magnification compared to one. Although this is well documented I've only just stumbled across it by comparing some big binoculars (16x70) with my spotting scope (20x60). Comparing in mono the scope view is bigger and sharper, as you'd expect. Use two eyes and both advantages are reversed in favour of the binos. 

Post edited at 11:59
In reply to Adam Long:

Cheers, Adam, interesting. I did actually write 90% of a reply to this but it got lost somehow. Essentially:

Where you say both advantages as reversed in favour of the binos, are you saying that an illusion of greater magnification when using binoculars, outweighs a loss in sharpness and reduction in scope view (in comparison to a monocular / spotting scope)? 

 Adam Long 01 Jul 2020
In reply to Blue Straggler:

Carefully comparing a one-eyed view through the binos with the scope, the extra magnification - 20x vs 16x - is obvious, and my scope has the edge on sharpness and contrast although it's subtle and only towards the edge where it's obvious. There's no reason why one should be sharper than the other but that's just the way mine happen to be.

But then comparing the two-eyed view the magnification somehow appears bigger in the binos and it's easier to see detail with higher apparent contrast. This was very marked looking at the moon, buts it's also true just looking at the landscape.

The two have similar apparent fields of view of about 65 degrees, but the lower mag of the binos gives a true field of view of 4.1 degrees vs 3.3. So the bino view is a bigger true field AND gives an illusion of greater magnification.

So with optics of similar quality, a scope/ monocular is going to need more impresssive/ expensive specs (higher mag and bigger objective lens) to offer a competitive view. Which I suppose explains why there are so many cheap binos around but monocular are pretty niche. But with the two I've compared I'm keeping both as the scope is more portable.

In reply to Adam Long:


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