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12-10-2011, 10:49 PM   #31
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QuoteOriginally posted by TOUGEFC Quote
I was wondering when the fence sitters would start the Sigma bashing
I'm not a sigma basher, I own several sigma EX series lenses myself. There is nothing wrong with criticism if I was being unfair I would be comparing Sigma 30mm f/1.4 to the Leica Summilux-M 35mm f/1.4.

QuoteOriginally posted by TOUGEFC Quote
I wonder if the new Sigma 85mm is the same
most likely - though I haven't seen any images from it to prove conclusively. And you are correct, the onion ring bokeh will only appear under certain specific situations.

12-11-2011, 01:20 AM   #32
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QuoteOriginally posted by Digitalis Quote
Interesting effect on the bokeh from the Sigma 30mm f/1.4 - those concentric rings in the blur circles gives me the impression that sigma do not grind their aspheric elements finely enough - you see that effect quite a bit in Sigma ASPH lenses.
Isn't this a problem of all aspherical lens elements?
Getting their surfaces smooth isn't nearly as easy as with spherical lens elements.

Luckily, "onion rings" are only really visible is certain extreme situations.

QuoteOriginally posted by TOUGEFC Quote
Yeah I too expected the 43 to be better , generally the Sigma does a nicer job IMO and has bigger discs.
It doesn't produce bigger discs from the same distance, does it?

QuoteOriginally posted by axl Quote
Well yes, side by side comparison like this reassured me that selling 77 in favour of 55 was a good decision, and that 43 despite being nice, and small and special doesn't measure up against the 55 for the style I want to be doing most of the time.
You are certainly entitled to make any conclusions from the comparison you like, but I personally believe that the comparison is useful for a very particular style of images (explicit, big, bokeh circles) but that it is impossible to derive typical image performance from it. The images are particularly unfit for making any general conclusions because the lenses were used at varying distances to the subject and I cannot think of another factor that is more important for background bokeh characteristic than subject/camera distance.

For instance, I agree that the 55's and the 77's bokeh circles look similar in the test, but in real life usage, to me personally the 77's bokeh is sublime while the 55's bokeh is a matter of taste (not my cup of tea).

Likewise, one may, or may not like the 43 but to find confirmation about the 55's performance regarding the 43 from the comparison seems odd to me. Again, in real life performance I find the 43's bokeh sometimes stunning, sometimes funky, but certainly always more interesting than the 55's bokeh.

At the end of the day, "each to their own", just wanted to comment that this comparison doesn't prove anything about real life performance for me.
12-11-2011, 02:08 AM   #33
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Series #3: I am assuming the backing lights are on a wall because of the 'smear glow' to the left of each light. I'd also say that the size of the COC combined with the FOV is the key to identifying the lenses. The bigger the COC the bigger the apertures etc. They all seem fine to me (as long as the glow to the left of each light is reflected light off a wall) and offer a different experience depending on what you're after.
12-11-2011, 02:22 AM   #34
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QuoteOriginally posted by Digitalis Quote
I'm not a sigma basher, I own several sigma EX series lenses myself. There is nothing wrong with criticism if I was being unfair I would be comparing Sigma 30mm f/1.4 to the Leica Summilux-M 35mm f/1.4..
Fair enough, it just seems like whenever the Sigma 30mm gets mentioned, your always the first to troll in and critcise it.


QuoteOriginally posted by bossa Quote
Series #3: I am assuming the backing lights are on a wall because of the 'smear glow' to the left of each light. I'd also say that the size of the COC combined with the FOV is the key to identifying the lenses. The bigger the COC the bigger the apertures etc. They all seem fine to me (as long as the glow to the left of each light is reflected light off a wall) and offer a different experience depending on what you're after.
Yeah the lights are hanging on a wall around double doors painted gloss. Hence the reflections


Last edited by TOUGEFC; 12-11-2011 at 02:37 AM.
12-11-2011, 02:32 AM   #35
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QuoteOriginally posted by Class A Quote
Isn't this a problem of all aspherical lens elements?
Getting their surfaces smooth isn't nearly as easy as with spherical lens elements.
You might be onto something here. FA*24 does produce onions at certain conditions and if you try hard enough I believe you could push 31 to it too (I'll have to check my pictures but I believe I traced onions in some).

QuoteQuote:
You are certainly entitled to make any conclusions from the comparison you like, but I personally believe that the comparison is useful for a very particular style of images (explicit, big, bokeh circles) but that it is impossible to derive typical image performance from it. The images are particularly unfit for making any general conclusions because the lenses were used at varying distances to the subject and I cannot think of another factor that is more important for background bokeh characteristic than subject/camera distance.

For instance, I agree that the 55's and the 77's bokeh circles look similar in the test, but in real life usage, to me personally the 77's bokeh is sublime while the 55's bokeh is a matter of taste (not my cup of tea).

Likewise, one may, or may not like the 43 but to find confirmation about the 55's performance regarding the 43 from the comparison seems odd to me. Again, in real life performance I find the 43's bokeh sometimes stunning, sometimes funky, but certainly always more interesting than the 55's bokeh.

At the end of the day, "each to their own", just wanted to comment that this comparison doesn't prove anything about real life performance for me.
Thank you for being so generous in letting me form my own conclusions

As you say, to each their own.
To me that means that even if certain situations the OOF areas produced by 77ltd might be smoother than those fro 55, the latter lens provides much more comfortable working distance while maintaing nearly undistinguishable IQ and subject isolation... But that's for the way I use the lenses..

Likewise, 43 being fantastic, yet on APSC is falling short of 55s capabilities of subject isolation. Again in MY way of using those two...

And on the side note, comparison like this says a lot about real life shooting, because it demonstrates just how much or little you have to change your camera - subjet distance, therefore perspective, to achieve similar framing. And since distance and perspective play major part in the way OOF areas are rendered, comparison like this is very telling.

My 2p
12-11-2011, 02:45 AM   #36
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I didn't notice the onion rings until I downloaded the pix and zoomed in. I'm going off to check my Sigma 50 right now..... I haven't seen any onion rings from it yet but that could be just a reflection of the subject matter etc...

The '43 doesn't look so good in this test I'm afraid.

Last edited by bossa; 12-11-2011 at 02:58 AM.
12-11-2011, 04:22 AM   #37
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QuoteOriginally posted by bossa Quote
I didn't notice the onion rings until I downloaded the pix and zoomed in. I'm going off to check my Sigma 50 right now..... I haven't seen any onion rings from it yet but that could be just a reflection of the subject matter etc...

The '43 doesn't look so good in this test I'm afraid.
Sigma 50 definitely can produce "onions" in the right situation. This has been one of the arguments for the DA *55 over it.
12-11-2011, 04:52 AM   #38
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Focusrite.... ;-)

The only thing around here that resembles xmas decorations is my Focusrite Liquid Mix. (no joke). The LED's on it are also raised buttons and so there's a two for one COC at each light.

Sigma 50 F/1.4 @ F/1.4.

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12-11-2011, 05:37 AM   #39
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QuoteOriginally posted by TOUGEFC Quote
Fair enough, it just seems like whenever the Sigma 30mm gets mentioned, your always the first to troll in and critcise it.
True, but I don't criticise lenses without good reason. I have used a lot of lenses in my time, and I have a preference for lenses that do not have any glaring technical flaws that can get in the way of my creative ideas. I know that people have a different aesthetic when it comes to lenses* than I do but I personally think a lens that has sharpness across the frame frees you to be creative with your compositions. Having the subject centred in the middle of frame can be a very weak composition, there are very few situations and subjects that let you get away with it. Using a lens with weak corners forces you to compose using the area where the lens performs at its strongest and in the end, the lens limits your options and I do not like that at all.

In the end it all comes down to personal taste, and what one considers to be "acceptable". Remember I started photography with a Leica M3 and a Summilux-M 50mm f/1.4 pre-asph - that is a pretty hard act to follow even today.

*I have colleagues that just love their holga cameras and their plastic lenses. Personally I cannot use them, I find it disconcerting when I see something and photograph it, and the camera comes up with something that is only an approximation of the subject. But I appreciate the images my colleagues produce with those cameras.

QuoteOriginally posted by Class A Quote
isn't this a problem of all aspherical lens elements? Getting their surfaces smooth isn't nearly as easy as with spherical lens elements. Luckily, "onion rings" are only really visible is certain extreme situations.
Well in my experience it only appears to be a problem with ground aspherics** and moulded aspheric lenses and as far as I can tell hybrid aspherics do not seem to be affected by this artifact. I surmise that is because of the manufacturing processes involved in creating them. If you end up using a lens with moulded or ground aspheric elements I just suggest you stop the lens down a bit or be strategic in how you incorporate the OOF lights so that post processing can be used to eliminate them if they are too distracting.

** It is rare to see this especially when taking into account the considerable lengths manufacturers go to produce ground aspherics. But I have seen this artifact even with some ultra-expensive lenses that incorporate ground aspherics into their design.

here are some "onion rings" from my FA31 (50%crop):

Last edited by Digitalis; 12-11-2011 at 05:23 PM.
12-11-2011, 01:47 PM   #40
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QuoteOriginally posted by axl Quote
And on the side note, comparison like this says a lot about real life shooting, because it demonstrates just how much or little you have to change your camera - subject distance, therefore perspective, to achieve similar framing.
I agree that the images say a lot about real life shooting in terms of the influence of subject/camera distance on background bokeh. In terms of differences in perspectives, not so much, AFAIC because of a lack of angles. In terms of real life bokeh, again, very little, unless you are able to factor out the very different shooting conditions for each lens.

QuoteOriginally posted by Digitalis Quote
here are some "onion rings" from my FA31(cropped):
There we have it, it is a terrible lens, after all!
12-12-2011, 09:32 AM   #41
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I'm not going to pretend to know the answers - but I love this!! The first set of photos looks amazing. I don't have any limited glass, but I'll have to try this tonight when I get home home and plug the tree in. Thanks for posting.
12-15-2011, 10:59 PM   #42
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Another note on the "onion Bokeh" phenomenon, after reviewing some images from a colleague of mine from the new Carl Zeiss Distagon 35mm f/1.4 and reading the marketing blurb about the new lens claiming that " The new Distagon also takes pictures of bright light sources without artifacts (sic)" after reading this I was certainly surprised to spot "onion rings" in a few images.

This artefact does not show up in images taken with the classic Ai-S Nikkor 35mm f/1.4 - which doesn't have an aspherical element. though I have noticed this effect in some images taken with my Nikkor 50mm f/1.4G - which doesn't have an aspherical element in it either. There is another hypothesis as to what causes this effect and it is said to be caused by refraction/reflection interaction occurring with the lens coatings between the lens elements.

Last edited by Digitalis; 12-15-2011 at 11:19 PM.
12-15-2011, 11:37 PM   #43
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I wouldn't be surprised if this effect is, at least partially, caused by the ground glass edges of the elements not being sufficiently smooth and blacked out.
12-16-2011, 01:17 AM   #44
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Anybody wants to play bit more?
https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/168627-xmas-ou...ml#post1745948
12-16-2011, 02:49 AM   #45
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QuoteOriginally posted by bossa Quote
I wouldn't be surprised if this effect is, at least partially, caused by the ground glass edges of the elements not being sufficiently smooth and blacked out.
The problem I can see with this theory is that it doesn't explain why with some lenses the rings appear darker than the ones around it?, And why isn't this effect the same for all lenses?

One thought did cross my mind of it being a bizarre kind of newton ring. I have come across cases where filters have been known to cause newton rings, but it isn't always repeatable as what we are seeing.

I took a peek at the Zeiss website on the specs on the 35mm f/1.4 and guess what I saw in the first image they have from this lens, look near the "D" in distagon and you will know what i'm talking about.

PS:

After doing some digging I found an article from a Dr.Hubert Nasse, on bokeh - and he also attempts to explain the origins of these artefacts - "It is possible to recognise from this that the lens has a aspherical surface as these surfaces are often not smooth as a conventionally polished lens. Particularly in the cases of lenses which are manufactured by pressing hot liquid glass it is possible to recognise the traces of the turning process with which the mould was manufactured." - Dr.Hubert Nasse
which is perfectly feasable IMO.

Last edited by Digitalis; 12-16-2011 at 03:30 AM.
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