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View Poll Results: Which do you prefer
FA35 3029.41%
FA31 7270.59%
Voters: 102. You may not vote on this poll

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06-29-2011, 06:08 PM   #91
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I am not sure a realistic vote is possible because the sun appears to have moved away from illuminating the top petals for the FA 35 shots, thus changing the dynamic range too much. And then, your camera adjusted exposure for the brightness the FA 31 saw, and that further skewed things by exposing for higher values with the 31 than for the 35. A better test would be shots taken under unchanging light conditions.


Last edited by les3547; 06-29-2011 at 10:36 PM.
06-30-2011, 11:34 AM   #92
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really difficult to judge.....personally I like FA31 saturated colours more, but FA35 gives here more 3d feel .... it is draw probably
06-30-2011, 10:50 PM   #93
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QuoteOriginally posted by les3547 Quote
A better test would be shots taken under unchanging light conditions.
I think I've said this a few times in this thread - the light conditions did not change. It was literally, 31 on, take shots, then mount 35, take shots, no breaks in between. No moving clouds to change the light.
06-30-2011, 11:04 PM   #94
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QuoteOriginally posted by selar Quote
I think I've said this a few times in this thread - the light conditions did not change. It was literally, 31 on, take shots, then mount 35, take shots, no breaks in between. No moving clouds to change the light.
Which would mean the FA35 received 25% more exposure (1/200 as opposed to 1/250, if memory serves). Like I said at the very beginning, if the light wasn't changing, this should have been shot on "M". Slight overexposure can appear as lowered contrast, and slight underexposure can appear as increased contrast. If the light was right at the "tipping point" between 1/200 and 1/250, you could easily end up with this situation on Av.

06-30-2011, 11:18 PM   #95
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Perhaps the FA31 lets more light through?
06-30-2011, 11:23 PM   #96
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QuoteOriginally posted by selar Quote
Perhaps the FA31 lets more light through?
Not 25% more! Sure, there could be differences in transmission, but it's usually fractional percentages. Like I said, if the threshold was right at the tipping point between 1/200 and 1/250, a 1% difference in transmission could flip one lens one way, one the other, resulting in a 25% (or maybe 24%? LOL) difference in exposure.
07-01-2011, 10:23 AM   #97
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QuoteOriginally posted by selar Quote
I think I've said this a few times in this thread - the light conditions did not change. It was literally, 31 on, take shots, then mount 35, take shots, no breaks in between. No moving clouds to change the light.
Sorry, I read through the thread but missed that. Plus, I think I was already believing the sun had shifted just based on how different the pictures look from each lens.

If nothing changed but the lenses, then I am not sure Steve’s explanation accounts for the differences. To me it appears that the FA31 is capturing highlights far better than the FA35. For example, if you study your pictures taken at f8, the shadow detail in the green leaves to the left comes through better with the FA35, which indicates your camera exposed a bit longer than it did with the FA31, as Steve suggests. But look at the highlights, not just on the leaves, but on the flower petals, on the little leaf in front of the pink flowers, on the mailbox (?I think that’s what that blueish-gray thing is in the background), on the gutter above the window, on the tops of the shrubs in front of the window . . . and that is the case at every aperture setting.

Obviously, since your camera was setting the exposure time automatically, it would have adjusted accordingly with each change in aperture; but I found myself doubting that a 25% change in exposure would make such a big difference in capturing highlights.

So, knowing Steve is a fan of the scientific method I decided to test his hypothesis as best I could given I can’t exactly recreate your situation. I used my Voightlander 40mm (as close as I could get to your lenses), set up a back lit scene with a flower (I didn’t have any pink ones) and made sure the petals were a bit illuminated, I shot close, and I set it at f4 for all pictures. I then used the AEL button to set exposure times by moving the camera until it read what I wanted.

I used six exposures ranging from 1/125 to 1/400 to see if that could make a difference in capturing highlights similar to what we saw in the differences between the FA31 and FA35.

1/125:


1/160:


1/200:


1/250:


1/320:


1/400:



Since none of the exposures eliminated highlights the way the FA35 did, my conclusion is that it seems more likely the FA31 (in your photos) was transmitting a better dynamic range.

Last edited by les3547; 07-01-2011 at 11:30 AM.
07-01-2011, 11:32 AM   #98
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QuoteOriginally posted by les3547 Quote
Sorry, I read through the thread but missed that. Plus, I think I was already believing the sun was different just based on how different the pictures look from each lens.

If nothing changed but the lenses, then I am not sure Steveís explanation accounts for the differences. To me it appears that the FA31 is capturing highlights far better than the FA35. For example, if you study your pictures taken at f8, the shadow detail in the green leaves to the left comes through better with the FA35, which indicates your camera exposed a bit longer than it did with the FA31, as Steve suggests. But look at the highlights, not just on the leaves, but on the flower petals, on the little leaf in front of the pink flowers, on the mailbox (?I think thatís what that blueish-gray thing is in the background), on the gutter above the window, on the tops of the shrubs in front of the window . . . and that is the case at every aperture setting.

Obviously, since your camera was setting the exposure time automatically, it would have adjusted accordingly with each change in aperture; but I found myself doubting that a 25% change in exposure would make such a big difference in capturing highlights.

So, knowing Steve is a fan of the scientific method
LOL!

QuoteQuote:
I decided to test his hypothesis as best I could given I canít exactly recreate your situation. I used my Voightlander 40mm (as close as I could get to your lenses), set up a back lit scene with a flower (I didnít have any pink ones) and made sure the petals were a bit illuminated, I shot close, and I set it at f4 for all pictures. I then used the AEL button to set exposure times by moving the camera until it read what I wanted.

Since none of the exposures eliminated highlights the way the FA35 did, my conclusion is that it seems more likely the FA31 (in your photos) was transmitting a better dynamic range.
That was certainly nice of you to undertake just for me!

I think you're looking at a combination of two things here; I think the FA31 does have more contrast, at least for this copy (I've observed before that I cannot re-create this circumstance with my FA35; the highlights remain clear and strong); however, the FA35 has more detail in the shadows AND the highlights:



If you zoom in on, say, the top petal on the right-hand flower - this bit:



It's clear that the 'blown out' bit is larger on the FA31 than on the FA35.

This creates a situation that's difficult to explain; if we take a lens with low contrast and expose it identically, we blow BIGGER highlights, typically - highlights tend to "bloom" in lenses with low contrast. So to get greater detail with lower contrast lenses in the highlights, we'd need to underexpose; OTOH, that would cause detail to drop out of the shadows, yet we have greater detail both in the shadows and in the highlights - and it's not just a loss of black, it's actual detail.

If you look at your 1/125 and 1/160th samples, you'll see on the top right petal that the first image has blown out bits considerably greater than those in the 1/160th, but the darker bits don't appear significantly darker. You've got a white flower, which pegs all channels at the same time, whereas the original was a pinkish/peachish flower, which would peg the red channel first. Just observations of things that would have to be normalized...

I can certainly understand why some might prefer the FA31, but I don't think there's any grounds here for an "objectively better lens" assertion (although if we're talking fit, finish, and feel in the hand, the FA31 wins hands down); just "different lenses".

I don't have an FA31, but I had an FA43 for a while, and it produced slightly more contrast than my FA35, but not nearly the difference we see here. A +5 on the contrast slider in lightroom rendered most images nearly identical. This looks more like a +35 to me.

07-01-2011, 11:42 AM   #99
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QuoteOriginally posted by jstevewhite Quote
You've got a white flower, which pegs all channels at the same time, whereas the original was a pinkish/peachish flower, which would peg the red channel first.
Are you saying I have to go out and find a pink flower?
07-01-2011, 11:53 AM   #100
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QuoteOriginally posted by les3547 Quote
Are you saying I have to go out and find a pink flower?
LOL! If you're trying to normalize for confounding variables, yeah. But I know you're just flippin me shite.

Just so you know I'm not talking through my hat, here's a couple of similar shots from my FA35, one on the metered exposure, one at -1 stop. Notice neither of them eliminates the backlit contrast the way selar's did. I can't explain why his did, but mine doesn't.
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07-01-2011, 12:37 PM   #101
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Just for fun, I found a pink flower. Not peachy, though - again, note that highlights exist as they should:
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07-01-2011, 12:52 PM   #102
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QuoteOriginally posted by jstevewhite Quote
Notice neither of them eliminates the backlit contrast the way selar's did. I can't explain why his did, but mine doesn't.
Well, one thing that would produce a difference in dynamic range is that it looks like he shot with a K-x, while you used the K-5. Also, I was looking at his pictures in the "windows live" link he provided, and you can see quite a bit of fidelity was lost between there and the posted pics. There the FA35 comes closer in matching highlights, but IMO still falls behind in resolution.

I see the point about wondering if the FA31 is as much better as its price suggests. I have wanted the FA31 because it fits better in my lens line up, though actually I wish there was a limited-quality 28mm for that spot (or better yet, a Voigtlander . . . I already tried the current production Zeiss 35mm, Pentax mount, and didn't like it at all . . . clunky, heavy, big and its resolution nowhere near that of the Voigtlander or the two Limiteds I've owned).

Last edited by les3547; 07-08-2011 at 08:37 PM.
07-01-2011, 01:05 PM   #103
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QuoteOriginally posted by les3547 Quote
Well, one thing that would produce a difference in dynamic range is that it looks like he shot with a K-x, while you used the K-5. Also, I was looking at his pictures in the "windows live" link he provided, and you can see quite a bit of fidelity was lost between there and the posted pics. There the FA35 comes closer in matching highlights, but IMO still falls behind in resolution.

I see the point about wondering if the FA31 is as much better as its price suggests. I have wanted the FA31 because it fits better in my lens line up, though actually I wish there was a limited-quality 28mm for that spot (or better yet, a Voightlander . . . I already tried the Zeiss and didn't like it at all . . . clunky, heavy, big and its resolution nowhere near that of the Voightlander or the two Limiteds I've owned).
The K20D produced very similar results - perhaps a bit more contrasty due to the lower dynamic range. These are not adjusted beyond import and export in LR3. I've never owned a K-X, so

I'm not certain what you mean by resolution. The FA35 and the FA31 are within fractional percentage points of the same MTF resolution (according to photozone.de), though the FA31 has better controlled CA, and they both produce significant PF in the right (wrong!) situations, and the FA35 is, at f4-5.6, ridiculously, bitingly sharp. I think the FA35 is a little more prone to flare, though, while we're on the subject. Don't leave home without your lens hood!
07-01-2011, 01:27 PM   #104
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QuoteOriginally posted by les3547 Quote
Well, one thing that would produce a difference in dynamic range is that it looks like he shot with a K-x, while you used the K-5. Also, I was looking at his pictures in the "windows live" link he provided, and you can see quite a bit of fidelity was lost between there and the posted pics. There the FA35 comes closer in matching highlights, but IMO still falls behind in resolution.

I see the point about wondering if the FA31 is as much better as its price suggests. I have wanted the FA31 because it fits better in my lens line up, though actually I wish there was a limited-quality 28mm for that spot (or better yet, a Voightlander . . . I already tried the Zeiss and didn't like it at all . . . clunky, heavy, big and its resolution nowhere near that of the Voightlander or the two Limiteds I've owned).
I'm playing with a Sigma 30mm f1.4 right now; focus is off, though, waiting for a repl from Amazon. It's not too shabby, though ( when I use LV AF or focus it manually ). Contrasty, sharp, colorful. Check it out if you get a chance. No, it's not Bavarian glass, but in these days of contrast and saturation sliders, sharp is more important, IMO...
07-01-2011, 01:47 PM   #105
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QuoteOriginally posted by jstevewhite Quote
I'm not certain what you mean by resolution. The FA35 and the FA31 are within fractional percentage points of the same MTF resolution (according to photozone.de)
Here's where we might not be able to agree . . . I'd trust what I see over any figures or chart; but let me attempt to describe differences in resolution I see between Selar's two pictures. Look at them in the "Windows Live" link where the quality is much better, and compare the FA31 and the FA35 at f4 (the third and sixth pictures).



Using the above crops for quick reference, I see more detail in the picture on the left, more depth (as on the surface of the lowest leaf), better color separation, better representation of shadows and highlights . . . overall it is more viscerally pleasing than the picture on the right, which in the past I've described as "flat looking." I might not be able prove it is more pleasing with figures, but I do know that I've had this reaction to other lenses, such as Leica and Voigtlander.

I also accept that others don't think the difference is worth fussing about, or paying for. But if the FA31 consistently produced such differences, I'd want it even for a premium price.

Last edited by les3547; 07-08-2011 at 08:36 PM.
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