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Where premium quality meets exceptional value. ZEISS Conquest HDX.

SFL 8x40 or 10x40? (1 Viewer)

Micealh

Active member
Ireland
I’d like to canvas thoughts. I want to buy one of these for my wife as a present. I have to buy online as there are no shops anywhere near us. She’s a relative novice but pretty sharp in the field. The light weight and compact shape of these will really suit her. She’s currently using a GPO ED 8x42 and occasionally complains that plumage details I’m talking about (Victory SF 10x42) are not altogether apparent to her. Could that be due to the GPO being simply less sharp, rather than lack of power? She never talks about field of view, although I wonder whether that’s because it’s good on her current GPO model (143/1000m) so she doesn’t notice. Do we sacrifice field of view (115/1000m on the 10x40 v. 140/1000m on the 8x40) for the extra power? Does anyone with experience of both binoculars want to offer an opinion?
 
Hello and welcome.

This link should provide you further information.


Regards
David
 
I had both the Zeiss SFL 8x40 and 10x40 and I sold them because I got the blue ring of death on both of them, which is a blue ring around the FOV caused by a type of CA. You or your wife may not experience this because glare can be different for everybody, but I did. Other than that, the SFL is a nice binocular, but I feel it is a bit overpriced for the optical performance.

The SF 10x42 will probably see plumage details a little better than the GPO ED 8x42. You're comparing a $500 binocular to a $2500 binocular, so optically the Zeiss SF is going to be better than the GPO ED. I am not entirely convinced you see more detail with 10x because what you gain in image size you lose in more shaking.

A 8x is steadier than a 10x, you have better DOF and a bigger FOV. I feel 8x is the sweet spot for birding binoculars, although some birders like the additional reach of a 10x, especially in open country.

If your wife likes a light compact binocular, I would recommend an NL 8x32 or SF 8x32 if price isn't an object. Optically, I think the NL is a tad better than the SF because it is sharper to the edge. If you don't want to spend that much, I would try a good mid-level binocular like the Zeiss Conquest HD 8x32 or the Nikon 8x42 MHG.

Both are small, light and compact and for less than $1000 they are a considerable jump up from the GPO ED in optical quality and build quality.

Either one will probably give her 90% of the view your SF will, and she should see similar plumage details, but an alpha is an alpha for good reason, and they are still going to give you a slightly better image, especially on something like plumage.
 
I had both the Zeiss SFL 8x40 and 10x40 and I sold them because I got the blue ring of death on both of them, which is a blue ring around the FOV caused by a type of CA. You or your wife may not experience this because glare can be different for everybody, but I did. Other than that, the SFL is a nice binocular, but I feel it is a bit overpriced for the optical performance.

The SF 10x42 will probably see plumage details a little better than the GPO ED 8x42. You're comparing a $500 binocular to a $2500 binocular, so optically the Zeiss SF is going to be better than the GPO ED. I am not entirely convinced you see more detail with 10x because what you gain in image size you lose in more shaking.

A 8x is steadier than a 10x, you have better DOF and a bigger FOV. I feel 8x is the sweet spot for birding binoculars, although some birders like the additional reach of a 10x, especially in open country.

If your wife likes a light compact binocular, I would recommend an NL 8x32 or SF 8x32 if price isn't an object. Optically, I think the NL is a tad better than the SF because it is sharper to the edge. If you don't want to spend that much, I would try a good mid-level binocular like the Zeiss Conquest HD 8x32 or the Nikon 8x42 MHG.

Both are small, light and compact and for less than $1000 they are a considerable jump up from the GPO ED in optical quality and build quality.

Either one will probably give her 90% of the view your SF will, and she should see similar plumage details, but an alpha is an alpha for good reason, and they are still going to give you a slightly better image, especially on something like plumage.
Thanks very much for taking the time to reply. That’s much appreciated.
 
Could that be due to the GPO being simply less sharp
This seems very unlikely to me. Have you compared the view between GPO and Zeiss, and what did you think? Or have you swapped bins with her, with what result? (That would also help to resolve whether 8x vs 10 is the issue or which she prefers, at whatever distance these birds are? But I think the two focus in opposite directions, so watch out for that.) Surely GPO ED is a good enough bin for most people to use productively. "Not seeing plumage details" can be a matter of not having learned yet to distinguish the details you're referring to. Or possibly not having the diopter set just right, or not having focused perfectly? (From near to far is recommended.) And it's not always about the equipment, one can just be tired too.
 
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Don't get carried away by the concept of "power".

Useful resolution is what you seek, not magnification. A better glass will usually have better resolution, and a superior 8X glass may out perform a lesser 10X.

I like the idea of trading with her for a while, and seeing how that goes. It will give you a lot of answers.
 
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I'd be surprised if diff in resolution (none of these are crap optics) was the issue. 10x, if otherwise comparing apples-to-apples, will give you more detail, but there is a valid point in saying that hand-shake will negate the improvement. THAT's totally dependent on the user. I'm typically hiking/birding, and getting older, so the 10's are a no-go. But I have owned 8 and 10x in same bino (Trinovid HD's and Noctivids), with opportunity to compare. I ended up selling off the 10's.

I would also caution against discarding a particular brand or model based on one or two BF reviews/comments. As example (sorry Dennis), Denco points out 'blue ring of death' with SFL's (we own 3 SFL's and find them to be the best bins for us and our style of birding, regardless of $$), yet recommends Swaro NL's - which several respectable reviewers have pointed out to have veiling glare issues. Just saying the latter, will quickly bring out NL defenders and this thread will get very lively :p

As soon as you move into the Conquest/MHG range (and above), the differences start to become 'academic'. They are real and they are there and you pay dearly for them, but it's more important to find bins where you like the ergos, flat vs pincushion view, warranty, etc.

A personal example: I dearly love the Leica 'look' (and build). But yesterday as I was using my 7X retros in front yard, I noted a Blue-gray Gnatcatcher flitting about in small evergreen. They're fast, the foliage was dense, and by the time I chased it with the Retros, I had missed it. It would not have happened with the SFL or FL or SF's which have FAST focusing with BIG grippy knobs. I still love the Retros for their qualities, but for hardcore birding I'll take the 30/40 SFL's all day long. I say that after having owned many (not all) of the rest of the obvious possibilities with the exception of Swaro.

...best to fondle some bins, provide honest appraisal of budget and intended use, and then decide ;-)
 
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Buy from a store where returns are easy and if possible go with her on a birding outing in your area where she can try out different binoculars. I prefer 10x but my wife prefers 8x. She has trouble with 10x and keeping the binoculars steady enough whereas my old eyes benefit from the higher magnification of 10x and 12x binoculars.
 
Buy from a store where returns are easy and if possible go with her on a birding outing in your area where she can try out different binoculars. I prefer 10x but my wife prefers 8x. She has trouble with 10x and keeping the binoculars steady enough whereas my old eyes benefit from the higher magnification of 10x and 12x binoculars.
Same for me. 8x (Conquest) I was constantly struggling to make out birds' more subtle features.
10x, (SFL 10x40) and steady hands seemed to have improved my birding
 
I think most binoculars, even those in price ranges below the GPO, are more than sharp enough, in the center, at typical birding distances. Going up in magnification to 10x may help in better seeing plumage detail - but also comes at a cost (more wobble/shake).

Probably the best thing to do would be to ask her to try your 10x42 SF (be warned - this may not be good for your bank balance...) and see how she gets along with the 10x42 format. If she does "see" better using a 10x magnification binocular, the 10x40 SFL may be an option. It's light, handy and the narrower field of view is not a real disadvantage in the majority of birding situations.

Just some more general thoughts re fieldcraft - if birding with a less experienced person I would recommend you use a lower magnification, or at least the same mag - so that if you see something, they'll see it with, at minimum, the same magnification/perspective, or "better" (with higher mag). If you are more experienced and using higher magnification binoculars, you will see more, from further away, than she does, which can be discouraging. If switching binoculars with her for a few sessions is not an option (how ungentlemanly! ... lol), it'll help her if you factor that in, and think like a bird guide almost - think about how to get your "client" a better view; maybe choose locations where the birds pop up fairly close and can easily be IDed with 8x. A bit of thought and planning can sometimes help a lot to increase a novice's enjoyment of the hobby.
 
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I think most binoculars, even those in price ranges below the GPO, are more than sharp enough, in the center, at typical birding distances. Going up in magnification to 10x may help in better seeing plumage detail - but also comes at a cost (more wobble/shake).

Probably the best thing to do would be to ask her to try your 10x42 SF (be warned - this may not be good for your bank balance...) and see how she gets along with the 10x42 format. If she does "see" better using a 10x magnification binocular, the 10x40 SFL may be an option. It's light, handy and the narrower field of view is not a real disadvantage in the majority of birding situations.

Just some more general thoughts re fieldcraft - if birding with a less experienced person I would recommend using a lower magnification, or at least the same mag - so that if you see something, they'll see it with, at minimum, the same magnification/perspective, or "better" (with higher mag). If you are more experienced and using higher magnification binoculars, you will see more, from further away, than she does, which can be discouraging. If switching binoculars with her for a few sessions is not an option (how ungentlemanly! ... lol), it'll help her if you factor that in, and think like a bird guide almost - think about how to get your "client" a better view; maybe choose locations where the birds pop up fairly close and can easily be IDed with 8x. A bit of thought and planning can sometimes help a lot to increase a novice's enjoyment of the hobby.
Thanks a lot. That’s a really thoughtful and empathetic response.
 
I had both the Zeiss SFL 8x40 and 10x40 and I saw the 'Blue Ring of Death' with both of them, which is a kind of CA which forms a thin blue ring around the edge of the FOV. You may not see it because not all see this type of glare, but I certainly did, so I would not recommend either one. Buyer beware!
 
I had both the Zeiss SFL 8x40 and 10x40 and I saw the 'Blue Ring of Death' with both of them, which is a kind of CA which forms a thin blue ring around the edge of the FOV. You may not see it because not all see this type of glare, but I certainly did, so I would not recommend either one. Buyer beware!
It's actually quite difficult to look at the edge of the fov. It's certainly not something you see when you use them to watch wildlife . You tend to look at the centre.
With my eyes at any rate , I have to look at an angle to see the edges, quite uncomfortable, but when I did, I couldn't see a blue ring. Saw a bit of orange glow at one point.
 
It's actually quite difficult to look at the edge of the fov. It's certainly not something you see when you use them to watch wildlife . You tend to look at the centre.
With my eyes at any rate , I have to look at an angle to see the edges, quite uncomfortable, but when I did, I couldn't see a blue ring. Saw a bit of orange glow at one point.
Not me! I notice the edge immediately, even if I am not directly looking at it. I can tell right away when a binocular has soft edges and when they are sharp to the edge. We are all different in that respect.

That is why I prefer Swarovski NL's. They have the biggest FOV around that is sharp to the very edge. That is the number one thing I look for in my binoculars, a big FOV with sharp edges.

When I had the Zeiss SFL 8x40 I was comparing it to a Swarovski SLC 8x42 and even the SLC had much sharper edges, and it seemed like the FOV was bigger. To be honest, IMO, the SLC just killed the SFL in a back to back comparison.

Then I looked at the soft edges of the SFL and I noticed they had a blue tint to them. The 'Blue Ring of Death' was showing its ugly face!

I sold the SFL's the next day and eventually replaced the SLC 8x42 with a NL 8x32 because the SLC had the typical crappy SLC focuser that has uneven tension in one direction, and it was sticky. About 80% of SLC 8x42 focusers are like that. Not the SLC 8x56, just the SLC 8x42.

The NL 8x32 has a much smoother focuser than the SLC, a much bigger FOV, it is smaller and lighter and has sharper edges. It has a little more glare in the bottom of the FOV, but I tolerate it for the other advantages.

I think if money is no object, the NL 8x32 is about the best birding binocular you can buy if you like a big FOV that is sharp to the edge. It tends to wow me more than other binoculars.

Honestly, if you can afford it, the NL 8x32 kills any of the SFL's. It has a way bigger FOV, sharper edges and no 'Blue Ring of Death'.
 
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I've never seen the so called blue ring on either the 10x40 SFL or the 8x40 SFL. I don't know of any other reports of it behalf from the above - there was some talk of it on other Zeiss bins (FL ?) I think.
 
It's actually quite difficult to look at the edge of the fov. It's certainly not something you see when you use them to watch wildlife . You tend to look at the centre.
With my eyes at any rate , I have to look at an angle to see the edges, quite uncomfortable, but when I did, I couldn't see a blue ring. Saw a bit of orange glow at one point.
Quite agree. When actually looking through the bins at birds etc, the edge sharpness for me does not really come into play. Sometimes I think certain users here are more obsessed with picking up on the smallest deficiency than with actually using the binocular for what they are intended for. I for one am very happy using the 2 SFL bins I have for birding.
 
Honestly, if you can afford it, the NL 8x32 kills any of the SFL's. It has a way bigger FOV, sharper edges and no 'Blue Ring of Death'.

I prefer the minimum focus distance of the SFLs. 10x and can literally focus down at my feet, which is amazing. Better for insects, reptiles and flowers etc.
I wouldn't get on with the NLs for that reason, or the price.
 

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