Yet another review of the 8x40 SFL (2 Viewers)

[james holdsworth]

Id say sharpness is what you see, resolution is something you measure.

 

[b-lilja]

Bill, I am pretty sure b-lilja is referring to Leica 7x42 here. He goes on to mention how he likes the lower magnification so is presumably talking about the 7x mag of the Ultravid.

Lee

Hi, Lee is right, and I can see that writeup is a bit confusing - not really compare and contrast between the listed bin and SFL. I think the 7x42 UVHD+ is maybe a half step less sharp/resolved than the SFL. I do know the 7x42 UVHD+ is less sharp/resolved than the Nvid based on direct comparos (actually of two copies of the 7x42s vs a Noctivid). I haven't done a direct comparo to the NL, but based on memory and relative to my current bins, the SFL is as sharp or resolved as anything else out there.

 

[Maljunulo]

So, are we or are we not using (and accepting) the words as synonyms?

 

[b-lilja]

James' note dropped while I was drafting mine. I'll leave it to others to decide. They seem the same to me as a non-measurer.

 

[dorubird]

Resolution means separating power and sharpness is a more generic and subjective term similar to clarity for me. I use the term "sharpness" or "clarity" when I want to sum up contrast and resolution together.
For example SF 10x42 and EL 10x42. Both give a general impression of high sharpness (good resolution and contrast), but only in comparison I noticed some difference between them: it can be seen that the sharpness of the EL is mainly given by the contrast and the sharpness of the SF is mainly given by the resolution (power of separate very fine details). So SW EL 10x42 has a higher contrast than the Zeiss SF 10x42, and SF has a higher resolution than the EL, but yet they are comparable in terms of sharpness.

 

[Troubador]

So, are we or are we not using (and accepting) the words as synonyms?

That is a good question and I think whatever we decide here on this thread, the answer will be 'yes' in practice as members use words/phrases like 'sharpness', 'perceived sharpness', 'resolution' and even 'clarity' in an informal way to refer to a combination of resolution and contrast that reveals fine details.
In principal I agree with James "sharpness is what you see, resolution is something you measure", but I don't expect members to strictly adhere to this.

Lee

 

[Vespobuteo]

That is a good question and I think whatever we decide here on this thread, the answer will be 'yes' in practice as members use words/phrases like 'sharpness', 'perceived sharpness', 'resolution' and even 'clarity' in an informal way to refer to a combination of resolution and contrast that reveals fine details.
In principal I agree with James "sharpness is what you see, resolution is something you measure", but I don't expect members to strictly adhere to this.

Lee

To complicate it even more...

In practice, when comparing two bins with the same lens diameter, a 10x bin will resolve more detail than an 8x bin (ie show a higher resolution), right? But the actual/theoretical maximal resolution of the two optical systems I guess need to be measured, and in theory it's limited by the lens diameters which in this case are the same.

So is it ok to state that I can see with my bare eyes that my 10x bin have "better resolution" than my 8x bin?

 

[Vespobuteo]

Resolution means separating power and sharpness is a more generic and subjective term similar to clarity for me. I use the term "sharpness" or "clarity" when I want to sum up contrast and resolution together.
For example SF 10x42 and EL 10x42. Both give a general impression of high sharpness (good resolution and contrast), but only in comparison I noticed some difference between them: it can be seen that the sharpness of the EL is mainly given by the contrast and the sharpness of the SF is mainly given by the resolution (power of separate very fine details). So SW EL 10x42 has a higher contrast than the Zeiss SF 10x42, and SF has a higher resolution than the EL, but yet they are comparable in terms of sharpness.

On a USAF-chart?

Did you star-test them? The EL SV might be a bad sample...

Contrast and resolution tend to correlate, at least in camera lenses that is MTF-tested.

 

[Troubador]

To complicate it even more...

In practice, when comparing two bins with the same lens diameter, a 10x bin will resolve more detail than an 8x bin (ie show a higher resolution), right? But the actual/theoretical maximal resolution of the two optical systems I guess need to be measured, and in theory it's limited by the lens diameters which in this case are the same.

So is it ok to state that I can see with my bare eyes that my 10x bin have "better resolution" than my 8x bin?

You are assuming the 8x and 10x bins are of similar optical quality and that is not necessarily always true.

You can state your 10x bins have better resolution but it might just be the case that they have better contrast which enables the naked eye to perceive more details.

And does it really depend on the lens diameters when in normal daylight your pupils are smaller and you are only receiving photons from a limited area in the centre of the lens?

And you did say, "to complicate it even more" and you were absolutely right

Lee

 

[dorubird]

Vespobuteo,​

Yes, I compared them on a USAF-chart! And Swaro EL has not bad resolution, not a bit!... but SF was slightly better in resolution!

"Contrast and resolution tend to correlate". Maybe, but not all the time, contrast and resolution are two completely different terms! For example we may have the following situations:
1 image with very high contrast and resolution
2 image with high contrast but with low resolution
3 image with low contrast but with high resolution
4 image with low contrast and resolution

Swarovski EL Swarovision 10x42 and Zeiss Victory SF10x42 are both clearly in category 1

But I noticed the following small differences, hardly noticeable only by comparing these two models:
Zeiss SF 10x42 has a slightly higher resolution, and Swarovski EL 10x42 has a slightly higher contrast, but the differences are small only regarding the image signature (like a kind of salt and pepper to taste).



here you can see some extremely examples with variations of contrast and resolution as in points 1, 2 and 3 listed by me above

How to Read MTF Charts

photographylife.com

 

[Vespobuteo]

Vespobuteo,​

Yes, I compared them on a USAF-chart! And Swaro EL has not bad resolution, not a bit!... but SF was slightly better in resolution!

"Contrast and resolution tend to correlate". Maybe, but not all the time, contrast and resolution are two completely different terms! For example we may have the following situations:
1 image with very high contrast and resolution
2 image with high contrast but with low resolution
3 image with low contrast but with high resolution
4 image with low contrast and resolution

Swarovski EL Swarovision 10x42 and Zeiss Victory SF10x42 are both clearly in category 1

But I noticed the following small differences, hardly noticeable only by comparing these two models:
Zeiss SF 10x42 has a slightly higher resolution, and Swarovski EL 10x42 has a slightly higher contrast, but the differences are small only regarding the image signature (like a kind of salt and pepper to taste).

here you can see some extremely examples with variations of contrast and resolution as in points 1, 2 and 3 listed by me above

How to Read MTF Charts

photographylife.com

I never suggested that they were the same terms...I said they may correlate. Depending on frequency MTF can be an indicator of the contrast of a lens.

From the link you posted:

" In the world of optics, resolution stands for the amount of fine detail that a lens is capable of transmitting (which is also known as “microcontrast”), while contrast stands for the ability of a lens to distinguish between different light intensities (e.g. blacks and whites). When contrast levels drop significantly, black and white lines eventually become gray and indistinguishable."

Therefore low contrast and high resolution does not seem to be consistent.

 

[dorubird]

I agree with everything written in that article, that's why I put the link, just to show that optical reality is much more nuanced when it comes to contrast and resolution! In the article it explains very well what microcontrast is. The microcontrast not to be confused with the general contrast of the image, it is acutance and it's not about the general contrast!

"Contrast and resolution tend to correlate". Maybe, but not all the time,

I have photo lenses with high resolution and high microcontrast but with low contrast! Voigtlander 35mm 1.7 Ultron Leica 39 mount version.

 

[Vespobuteo]

You are assuming the 8x and 10x bins are of similar optical quality and that is not necessarily always true.

You can state your 10x bins have better resolution but it might just be the case that they have better contrast which enables the naked eye to perceive more details.

And does it really depend on the lens diameters when in normal daylight your pupils are smaller and you are only receiving photons from a limited area in the centre of the lens?

And you did say, "to complicate it even more" and you were absolutely right

Lee

Yes sir, similar optical quality implied.
But as it seems, resolution or resolving power may be measured or perceived.

Eye pupil should set the limit yes, and aberrations in the eye usually get worse with a larger pupil.

Contrast affects the amount of perceive details,
thus I find it slightly peculiar that some can describe the contrast of a binocular as "too high".

I guess it can't be higher than the actual scene that is viewed?
Perhaps some prefer a slightly softer view of the harsh reality?

 

[Ted Y.]

The microcontrast not to be confused with the general contrast of the image, it is acutance and it's not about the general contrast!

Thank you.
I think this subject deserves a thread. Or more.

 

[Vespobuteo]

I agree with everything written in that article, that's why I put the link, just to show that optical reality is much more nuanced when it comes to contrast and resolution! In the article it explains very well what microcontrast is. The microcontrast not to be confused with the general contrast of the image, it is acutance and it's not about the general contrast!

I have photo lenses with high resolution and high microcontrast but with low contrast! Voigtlander 35mm 1.7 Ultron Leica 39 mount version.

Microcontrast is the Big Foot and Fairy dust of Photography it seems....

Micro Contrast, Is It a Myth?: Open Talk Forum: Digital Photography Review

Expert news, reviews and videos of the latest digital cameras, lenses, accessories, and phones. Get answers to your questions in our photography forums.

www.dpreview.com

Contrast is at least based on a scientific definition so I'll stick to that term.

"image fidelity" might be a better general term to use with a slight problem.

With Binoculars we don't have an image artifact to objectively compare to the original.

What was the question btw?
🤣

EDIT: As expected , the term "micro contrast" first occurs in the photographic community in a Leica Lens Mythology dedicated page 1997:

Older M lenses | LEICA

 

[Bill Atwood]

Hi, Lee is right, and I can see that writeup is a bit confusing - not really compare and contrast between the listed bin and SFL. I think the 7x42 UVHD+ is maybe a half step less sharp/resolved than the SFL. I do know the 7x42 UVHD+ is less sharp/resolved than the Nvid based on direct comparos (actually of two copies of the 7x42s vs a Noctivid). I haven't done a direct comparo to the NL, but based on memory and relative to my current bins, the SFL is as sharp or resolved as anything else out there.

I did read your post a bit too fast.

 

[Maljunulo]

What was the question btw?
🤣

Are sharpness and resolution the same thing, and may the words be used interchangeably?

 

[Vespobuteo]

Are sharpness and resolution the same thing, and may the words be used interchangeably?

No, similar to my example above;
a 10x bin resolves more than an 8x, but they can be equally sharp IMO.

EDIT. Technically assuming same optical quality and objective size, the 10x might not actually resolve more, but it's easier to see more details, due to the magnification...perceived resolution is higher?

Having very good eye sight/acuity, I guess the 8x could show the same amount of detail?

Sharpness is just sharpness.

 

[dorubird]

Yes, microcontrast is a more vague term because it is used many times without knowing its exact meaning, when one wants to express something of indefinite good sharpness.
For me microcontrast is "acutance". Another exotic term 😀 but explained well in that link.

 

[Ted Y.]

You are assuming the 8x and 10x bins are of similar optical quality and that is not necessarily always true.

Same for 10x and 12x. I was difficult to find a 12x having the same quality as the 10x in the same model. Premium binoculars excluded.