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08-02-2017, 04:41 PM   #1
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Lenscore.org is good, but they are NOT perfect

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For many months now I have regularly frequented a lens rating website called Lenscore.org. Specifically, I have spent countless hours studying their Zeiss lens ratings.

Having owned and used all but one of the Zeiss classic lenses and a few of the Zeiss Milvus lenses, I've developed some strong personal feelings about many Zeiss lenses.

While for the most part, I find the Lenscore.org ratings to be fair and accurate; they sometimes really miss the mark with their scores. This is especially true when it comes to their scores on a lens' bokeh.

For example, a Zeiss lens with exceptional bokeh is the 35mm f/1.4 "Classic" lens. Not only is that my opinion, but one of the best lens testers in the USA (Roger Cicala of LensRentals.com) says "The bokeh is like butter, as nice as anything I’ve shot with and definitely better (in my opinion) than the Canon or Nikon 35 f/1.4s." . Lenscore.org rates the bokeh of the Zeiss 35mm f/1.4 lens a lowly 22 out of 30 Zeiss lenses they evaluated.

Bokeh is not easy to evaluate and rate. Maybe someone needs to come up with a standardized lens bokeh measuring protocol that, once and for all, brings uniformity to this here-to-for subjective lens characteristic.

Without an objective way to evaluate and test lens characteristics, maybe a lens reviewer (like Lenscore.org) should refrain from commenting at all on that particular lens characteristic. Because making evaluations that are highly subjective will bring into question the validity of their other evaluations on the many other lenses characteristics.


Last edited by Fenwoodian; 08-02-2017 at 04:52 PM.
08-02-2017, 04:47 PM - 3 Likes   #2
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QuoteOriginally posted by Fenwoodian Quote
. Maybe someone needs to come up with a standardized lens bokeh measuring protocol that, once and for all, brings uniformity to this here-to-for subjective lens characteristic.

In my not so humble opinion, it's too difficult to quantify. Kind of like standards for rating pizza or something.
08-02-2017, 04:47 PM   #3
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QuoteOriginally posted by Fenwoodian Quote
Bokeh is not easy to evaluate and rate. Maybe someone needs to come up with a standardized lens bokeh measuring protocol that, once and for all, brings uniformity to this here-to-for subjective lens characteristic.
how?

by definition, bokeh is entirely subjective...
08-02-2017, 04:56 PM   #4
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QuoteOriginally posted by pepperberry farm Quote
how?

by definition, bokeh is entirely subjective...

That's my point. Why even bother to rate something that has no objective evaluation criteria, because it will only serve to make the evaluator look bad and make people question the validity of their ratings of other lens characteristics that are objectively determined.

However, while bokeh is subjective NOW, that's not to say that a standard could not be developed in the future to objectively evaluate bokeh. After all, USA Today, HuffPost and many others regularly rate the best Pizza's in the USA based upon objective measures they've created for their testing. For example, I think most would consider double edges on out of focus background objects to be objectionable. So, there's one objective measure of good bokeh - and I expect that most of you could come up with other objective measures of bokeh.


Last edited by Fenwoodian; 08-02-2017 at 05:11 PM.
08-02-2017, 04:59 PM   #5
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we do bokeh ratings here as part of the lens review section - it seems to be valid, especially if the reviewer can provide proof of said bokeh and explain their rating of it...
08-02-2017, 05:22 PM - 3 Likes   #6
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There are many objective measurements that could be done to assess bokeh:

1. Overall uniformity across the bokeh circle:

2. Granularity uniformity across the bokeh circle:

3. Variation of bokeh shape across the frame

4. Chromatic aberrations of the bokeh edge

Of course, how you weight all these factors might be subjective with some especially prized types of bokeh (soap bubbles and swirly bokeh) being caused by particular types of non-uniformities.

P.S., Unless they test multiple copies of each lens and all lenses are tested on the body you plan to use, some of these bokeh properties might be mis-measured. Both bokeh uniformity and granularity are affect by the sensor, too.
08-02-2017, 05:25 PM - 3 Likes   #7
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Double-line bokeh, onion rings, cat's eyes, hard polygons -- these all seem like qualities that should be measurable and are usually considered undesirable.

I'm not so sure about rims: soap bubbles or hard rims might be desirable for some and not for others. Same with extended intelligibility in the background transition area like what the Nikkor 58/1.4 G is documented to have here -- I want to say this seems like undercorrected spherical aberration and is most likely to be found together with focus shift, and from what I've heard I'd be curious to see if the Planar 85/1.4 exhibits this as well (Fenwoodian?) -- it might make the background look better but the foreground worse, if those hard rings are any indication.

08-02-2017, 05:35 PM - 2 Likes   #8
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Fenwoodian,

You are the best advertisement for Zeiss lenses on Pentax. When I was browsing that long K1 photos thread thinking about lens purchases the only ones that made me unconsciously say something like "holy $%!&!" were Zeiss lenses - especially a photo of dangling light bulbs with frost on them. The bokeh and overall tonality of that image was just amazing.

I'd love it if you would compile your observations on the available Zeiss lenses in a thread all by themselves that I can reference when my budget increases.

I think your knowledge and perception in this area might be unique, and very valuable.
08-02-2017, 05:53 PM - 1 Like   #9
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QuoteOriginally posted by Derek Zeanah Quote
Fenwoodian,

You are the best advertisement for Zeiss lenses on Pentax. When I was browsing that long K1 photos thread thinking about lens purchases the only ones that made me unconsciously say something like "holy $%!&!" were Zeiss lenses - especially a photo of dangling light bulbs with frost on them. The bokeh and overall tonality of that image was just amazing.

I'd love it if you would compile your observations on the available Zeiss lenses in a thread all by themselves that I can reference when my budget increases.

I think your knowledge and perception in this area might be unique, and very valuable.

I'm busy now with other projects so a massive report on Zeiss lenses is not something I have time for. However, do your own research on Zeiss lenses. Once you've boiled down your wish list to a limited few lenses, send me a personal message and I'll respond with comments on each of your finalists. I did just this with a professional landscape photographer this last weekend who was a complete stranger to me. I enjoyed the interaction with him, and in the end, he decided that the best Zeiss wide angle for him was the Zeiss Milvus 18/2.8.

If Pentax doesn't start releasing their new roadmap lenses pretty soon, I suspect more and more K1 owners will start seriously considering adapting Zeiss lenses.

Last edited by Fenwoodian; 08-02-2017 at 05:58 PM.
08-03-2017, 05:37 AM - 2 Likes   #10
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Bokeh is an odd thing. Some people seem to like odd bokeh, while I prefer smoother. It also depends on aperture -- some lenses are smooth wide open, but get really weird stopped down a little -- some are the opposite. Most macro lenses have "nice" bokeh when focusing really close and everything is sort of blurred into oblivion, but get a little more distance and out of focus areas are more rough.

The biggest thing to me is the transition area between in focus and out of focus. Some lenses do that pretty well, others not so well.

Last edited by Rondec; 08-03-2017 at 08:29 AM.
08-03-2017, 06:28 AM - 1 Like   #11
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The technical specs of lenses in no way predicts whether or not people enjoy the images taken with that lens. The lens comparisons I've run here on the forum demonstrate that conclusively. Lens ratings are a waste of time. Everyone has different tastes and everyone enjoys different levels of technical performance. For people, the best technical lens is not necessarily the lens that produces the most pleasing rendition.

I'm not sure how technical evaluations of lenses should appeal to, but to me they are just another factor in clouding your judgement and making it harder to find the lens you love. There is a small correlation between lens quality and viewers appreciation of the images, better lenses do attract more "likes" than kit lenses, but once you pass a certain threshold, other considerations besides technical ,merit on test charts become more important.

No lens company has ever proved that more people like the images from their really expensive lenses. I know the lens testers think they know something, I know the lens designers think they know something, I know many folks are sucked in to the whole measuring tech specs thing/ I've just never been able to devise a test that shows people actually think highly rated lenses are better in blind tests. And as far as I can tell neither has anyone else.

In fact my own polls have shown the opposite. Especially at web size the majority of people do not find the sharpest highest technically rated the lens to be their favourite image. Once you get to the level of mid quality lenses and up, anything say Tamron 17-50 level and over, no lens is favoured by the majority of users and the largest number of preferences out of a group of 7 any lens is likely to achieve is about 30% no matter how good people might think it is.

My polls suggest if you buy on technical specs, 70% of the time you will buy a lens that you wouldn't have voted it's image as the top rated image. IN other owrds you're paying the big bucks for lenses you don't really like. You've just talked yourself into thinking you like it based on a less than through evaluation of various technical parameters. Photography is art.

Given that in one of my polls my lowly FA 35-80 garnered a few votes over my more expensive sharper lenses, what kind of person would recommend buying a $6000 lens when they might prefer the images of a $60 film lens? Ignore the hype people, Lens testers do not tell you the one thing you need to know. Do you like the images from the lens.Everything else is nonsense.

Lens testers overate technical values, and completely ignore artistic rendering, because they can't quantify the factors that people appreciate in a lens. They do us all a disservice by then trying to ignore the factors, as if if you can't measure it it doesn't exist. To the artistic eye, it's the overall rendering of the lens that's important, the technical values have nothing to do with it. A $60 lens can render images better than the proverbial $5000 lens, in the right circumstances, possibly your circumstances.



Superiority in selected technical specs does not translate to superiority in artistic rendering. And the differences between middle of the road lenses and really expensive lenses are largely imaginary as far as I can tell, for everyone but Pixel peepers. And even then it happens that people see the difference in resolution etc pixel peeping, but still prefer the images of a lower res not as corrected lens when they stand back and take a look at the image. Pixel peeping is a disease of fixation with small detail. Seeing the trees and missing the beauty of the forest.

Some people seem destined to let their worship of technical specs diminish their enjoyment of the images they take. They may have bought the Zeiss, but they would have preferred the images from the 35-80.

Last edited by normhead; 08-03-2017 at 06:51 AM.
08-03-2017, 06:42 AM   #12
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QuoteOriginally posted by normhead Quote
Lens ratings are a waste of time.


thank you for stating that....
08-03-2017, 07:10 AM   #13
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QuoteOriginally posted by normhead Quote
The technical specs of lenses in no way predicts whether or not people enjoy the images taken with that lens. The lens comparisons I've run here on the forum demonstrate that conclusively. Lens ratings are a waste of time. Everyone has different tastes and everyone enjoys different levels of technical performance. For people, the best technical lens is not necessarily the lens that produces the most pleasing rendition.

I'm not sure how technical evaluations of lenses should appeal to, but to me they are just another factor in clouding your judgement and making it harder to find the lens you love. There is a small correlation between lens quality and viewers appreciation of the images, better lenses do attract more "likes" than kit lenses, but once you pass a certain threshold, other considerations besides technical ,merit on test charts become more important.

No lens company has ever proved that more people like the images from their really expensive lenses. I know the lens testers think they know something, I know the lens designers think they know something, I know many folks are sucked in to the whole measuring tech specs thing/ I've just never been able to devise a test that shows people actually think highly rated lenses are better in blind tests. And as far as I can tell neither has anyone else.

In fact my own polls have shown the opposite. Especially at web size the majority of people do not find the sharpest highest technically rated the lens to be their favourite image. Once you get to the level of mid quality lenses and up, anything say Tamron 17-50 level and over, no lens is favoured by the majority of users and the largest number of preferences out of a group of 7 any lens is likely to achieve is about 30% no matter how good people might think it is.

My polls suggest if you buy on technical specs, 70% of the time you will buy a lens that you wouldn't have voted it's image as the top rated image. IN other owrds you're paying the big bucks for lenses you don't really like. You've just talked yourself into thinking you like it based on a less than through evaluation of various technical parameters. Photography is art.

Given that in one of my polls my lowly FA 35-80 garnered a few votes over my more expensive sharper lenses, what kind of person would recommend buying a $6000 lens when they might prefer the images of a $60 film lens? Ignore the hype people, Lens testers do not tell you the one thing you need to know. Do you like the images from the lens.Everything else is nonsense.

Lens testers overate technical values, and completely ignore artistic rendering, because they can't quantify the factors that people appreciate in a lens. They do us all a disservice by then trying to ignore the factors, as if if you can't measure it it doesn't exist. To the artistic eye, it's the overall rendering of the lens that's important, the technical values have nothing to do with it. A $60 lens can render images better than the proverbial $5000 lens, in the right circumstances, possibly your circumstances.



Superiority in selected technical specs does not translate to superiority in artistic rendering. And the differences between middle of the road lenses and really expensive lenses are largely imaginary as far as I can tell, for everyone but Pixel peepers. And even then it happens that people see the difference in resolution etc pixel peeping, but still prefer the images of a lower res not as corrected lens when they stand back and take a look at the image. Pixel peeping is a disease of fixation with small detail. Seeing the trees and missing the beauty of the forest.

Some people seem destined to let their worship of technical specs diminish their enjoyment of the images they take. They may have bought the Zeiss, but they would have preferred the images from the 35-80.
I think that from what I've seen contrast is actually more valuable than sharpness, when it comes to lens performance, but all of these take a back seat to composition, lighting and subject. I've not seen a lens yet that can turn a poorly composed, uninteresting photo into major art.

The big thing I think that having top end lenses does is it gives you the ability to print larger. As you say, at web sizes, these probably all look about the same. On the other hand, printed really large (40 inches on a side), you can really see sharpness and the presence (or lack) of detail in an image.

I saw your lens test comparison and I honestly couldn't tell the difference between the images at the size posted on the forum. Could I if they were printed big enough? Maybe. If you took them all out and shot a sunrise right into the sun, would some have flared more than others? Probably. But as shot, they were pretty close.
08-03-2017, 07:28 AM - 1 Like   #14
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QuoteOriginally posted by Rondec Quote
I saw your lens test comparison and I honestly couldn't tell the difference between the images at the size posted on the forum. Could I if they were printed big enough? Maybe. If you took them all out and shot a sunrise right into the sun, would some have flared more than others? Probably. But as shot, they were pretty close.
That was exactly my point. Unless you print really large, you may prefer a lower res lens. The artistic merit of the lower res lens may in fact be more valuable to you than the sharpness of the higher rated lens. I agree with you on the contrast. There is practically no difference between a DA*60-250 image and a Tamron 90 image at 90mm, but pixel peeping the Tamron's micro-contrast is better, giving it a slight edge. But it would be a very big print before you'd see that. At least 50 inches across. The largest size we did for the craft show sales were 30x20 canvases, At that size our most often sold image was taken with 12 MP point and shoot. So, I'm not even going to entertain the value of high-res images, unless you plan to print bigger than 30 x 20 inches. I believe one of eddie1960's cousins prints really big and gets $5000 a print, but unless you have access to that kind of market, going for the highest possible resolution is a waste of your money. I've never actually determined at what point you need high resolution for your images. I don't think anyone else has either. If people seem to like 12 MP at 30x20 to pay $300 for a print, you have to ask yourself, what am I really going to achieve going for a high res lens?

I've always been of the opinion, nothing more than bragging rights. And I'll keep that opinion until some one shows me different. I'm not arguing that you can't see a difference pixel peeping. I'm arguing pixel peeping is a very poor way to evaluate a piece of art, and is essentially irrelevant.

Last edited by normhead; 08-03-2017 at 01:27 PM.
08-03-2017, 08:47 AM - 3 Likes   #15
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It is hard to evaluate bokeh out of context with an image.

This is the FA 77 limited at f2:



I happen to like the image a lot. The background is blurred out effectively and doesn't detract from the image.

This is the DA *200 at f3.5



Here, the background is a bigger part of the image. Still, the big thing is that it doesn't get in the way of the image.

This is the DA *55 at f2.



To me, this bokeh is more busy and distracting. But it is also a lot tougher shot as the background is significantly closer than in the previous two images. The FA 77 might do better, but maybe not...

All that said, I don't know how to quantify it. I think most reviewers just take a photo of unfocused lights and then just evaluate if there are any of the weird things like polygons or donuts, etc that detract from out of focus rendering. Which is a start. But a picture is worth a thousand words.
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