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05-22-2011, 07:37 AM   #226
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RESPONSE #226:

Yes, the 31 is much better, if you need a 31.
No, the 31 isn't much better, if you need a 40.
Case closed.

05-22-2011, 09:26 AM   #227
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QuoteOriginally posted by RioRico Quote
RESPONSE #226:

Yes, the 31 is much better, if you need a 31.
No, the 31 isn't much better, if you need a 40.
9mm isn't enough variation to say one needs one or the other focal lengths, as most advocates who wax eloquently about the merits of prime lenses fancy this notion of "zooming with your feet".

More to come later today.
05-22-2011, 09:43 AM   #228
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QuoteOriginally posted by JHD Quote
9mm isn't enough variation to say one needs one or the other focal lengths, as most advocates who wax eloquently about the merits of prime lenses fancy this notion of "zooming with your feet".

More to come later today.
I dunno... ~25% is a big difference in FOV, IMO; "Zooming with your feet" will significantly change the picture. I supposed it depends on your definition of "need"; do you "need" it for a compositional decision? (in which case they aren't interchangeable) Or do you just need a certain subject size for your image? (in which case they are).

31mm=41 degree FOV
40mm=32 degree FOV
05-22-2011, 10:46 AM   #229
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QuoteOriginally posted by JHD Quote
9mm isn't enough variation to say one needs one or the other focal lengths, as most advocates who wax eloquently about the merits of prime lenses fancy this notion of "zooming with your feet".
Fully agree. This is what zooms are for. Buy a prime for your absolute favorite focal lengths... not every useful one...

You are gonna be stopping those lenses down anyways. I love the speed of the 50 and 77, but I don't need that kind of speed at every focal length.

05-22-2011, 11:28 AM   #230
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21 vs 24 is small but significant. 24 vs 28 is small but significant. 28/30 vs 35 is yet small but more significant. 35/37 vs 40; 40 vs 45; 45 vs 50; 50 vs 55/58; the small differences add up. I have f/2's at 24, 28, 35, 58, 85. And faster at 50 and 55, and slower at 21 and 40 and 45 and 100 etc. And yet slower zooms 'covering' those ranges.

So, what will be in my carry-bag at any moment depends on what I expect to shoot, and which small (but significant) differences I wish to exploit. No, I won't carry a 21 and 24 at the same time, nor 24 and 28, nor 28 and 35, nor 35 and 40, nor 45 and 50, nor 50 and 55, etc. Even my porter Ansel won't schlep that much around, let alone my poor pack-llama. But for any given situation, a 35 or 37 or 40 or 42 or 45 or 48 or 50 or 53 or 55 or 58 or 60 or 65 may be JUST THE RIGHT LENS, so I won't sell those.

And maybe the F35-70 zoom is 'better' than the Meyer Primagon 35/4.5 or Helioplan 40/4.5, but they just don't 'taste' the same. Coverage is not character. My only zoom that maintains 'character' over its range is the Schneider Betavaron 50-125mm enlarger zoom -- it is brutally, mercilessly sharp everywhere. But some subjects won't survive its character. So, different tools for different purposes, eh?
05-22-2011, 11:40 AM   #231
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QuoteOriginally posted by RioRico Quote
And maybe the F35-70 zoom is 'better' than the Meyer Primagon 35/4.5 or Helioplan 40/4.5, but they just don't 'taste' the same. Coverage is not character. My only zoom that maintains 'character' over its range is the Schneider Betavaron 50-125mm enlarger zoom -- it is brutally, mercilessly sharp everywhere. But some subjects won't survive its character. So, different tools for different purposes, eh?
Very reasonable assessment, and doesn't invalidate LBA, so ...

I had the problem you described with your Betavaron with my Hassy when I first got it. Many people weren't happy with the way it made every flaw apparent ( and every hair, wrinkle, and blemish LOL ). I ended up buying a Softar to balance that out a bit.
05-22-2011, 11:53 AM - 1 Like   #232
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look, i haven't used either (awaiting delivery of my 31mm and 77mm in the the coming days) but a lot of this talk about FL merits a point.

'zooming with your feet' is more necessary - and more beneficial, it's fairly arguable - with wider/shorter FLs. each step/inch makes a bigger difference, the shorter your FL. therefore, the 31 - which translates to a short standard - would benefit more from 'zooming with your feet' than the 43, which translates to a short tele.

i am a bit of prime/sharpness junkie, and just parted with my DA 40 because - though *insanely* sharp - the FL is just not as useful to me (who needs a 60mm equivalent lens? not enough working distance for a natural perspective head-shot portrait, not wide enough for environmental). i cannot envision needing any sharper, and the equivalent FOV of the 43 = 65-66mm. awkward at best. if you just want to shoot your nearest and dearest from a hair too close with enough sharpness to make them rush out and buy a new cleanser and moisturiser, fine. there's a reason why a super portraitist like Jane Bown used an 85mm lens her entire career. is why i am looking at the voigtlander 58mm (closest FL to 85mm equiv, 1.5 x 58 = 87 = PERFICK!). have been manually focussing for 17 years, AF is a luxury it's nice to have but not really necessary for me.

if the 31 becomes a 'short standard' (i.e. equiv FOV of 46mm), that immediately makes it much, much more versatile for general photography/walkaround to my mind. if the rendering is all its cracked up to be, so much the better. fairly sure it will equal the previous standard-setting combo (for me) of a Zuiko 40mm on a 5DII. and that's what i'm after, but with better ergonomics.

now if i had that MZs i'm quietly going about acquiring, that 43 would be *just* right...
05-22-2011, 12:03 PM   #233
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QuoteOriginally posted by zuikoholic Quote
look, i haven't used either (awaiting delivery of my 31mm and 77mm in the the coming days) but a lot of this talk about FL merits a point.

'zooming with your feet' is more necessary - and more beneficial, it's fairly arguable - with wider/shorter FLs. each step/inch makes a bigger difference, the shorter your FL. therefore, the 31 - which translates to a short standard - would benefit more from 'zooming with your feet' than the 43, which translates to a short tele.

i am a bit of prime/sharpness junkie, and just parted with my DA 40 because - though *insanely* sharp - the FL is just not as useful to me (who needs a 60mm equivalent lens? not enough working distance for a natural perspective head-shot portrait, not wide enough for environmental). i cannot envision needing any sharper, and the equivalent FOV of the 43 = 65-66mm. awkward at best. if you just want to shoot your nearest and dearest from a hair too close with enough sharpness to make them rush out and buy a new cleanser and moisturiser, fine. there's a reason why a super portraitist like Jane Bown used an 85mm lens her entire career. is why i am looking at the voigtlander 58mm (closest FL to 85mm equiv, 1.5 x 58 = 87 = PERFICK!). have been manually focussing for 17 years, AF is a luxury it's nice to have but not really necessary for me.
+1 Very well put. I just ordered a Helios 44m-4 to check out that 58mm FL; and bought a DA 70mm (I was always a fan of the 100-105 FL)... but your point about 85 is well taken; I made more money with my beat up old Canon FD 85 1.8 than all my other 35mm lenses put together.

05-23-2011, 05:21 AM   #234
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BACK TO THE ORIGINAL QUESTION

Is the FA31 really 2.8 times better than DA40?


That is highly dependant on YOUR expectations and what you demand from a lens that costs 2.8 times more than the DA40.

In short - strictly on the merits of optical quality - this is what I see after comparing 2 sets of controlled samples provided by members mccarvindh & sjwaldron...

TEST 1 - by mccarvindh

Wide Open... the two lenses are not really comparable here as the aperture on the FA31 opens up significantly wider than the DA40. A more appropriate budget comparison would be with the Sigma 30, which opens up to f1.4. That however is not the lens in question.

However at f4... the DA40 is substantially sharper with more contrast than the FA31. The definition in the details, both obvious and subtle is very apparent. Load these shots into a viewer and flip between them and you will see what I mean. I even cropped the image of the DA40 closer to the same FOV as the FA31. At F4 the DA40 is the clear winner.


TEST 2 - by sjwaldron - here's where things get interesting

At f2.8... In this set of controlled samples now the FA31 reveals more detail and better contrast, but not to the same extent of the previous test at f4 where the DA40 really shined. Also the f2.8 sample from the FA31 seems brighter suggesting disparity in exposure, however PhotoMe reveals both images were shot at identical parameters.

At f5.6... it's a tougher call but rather than calling it a draw the balance tips in favor of the FA31.


~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~


In conclusion one has to consider the possibility sample variation. Perhaps the DA40 belonging to mccarvindh is much sharper copy than the copy of belonging to sjwaldron? And perhaps the FA31 belonging to sjwaldron is better than the copy belonging to mccarvindh? Speculation yes, but plausible as it is well known that copies the same lens can vary from copy to copy.

Some might and have argued at the validity of such a comparison but as I see it, if there isn't an appreciable difference between two lenses under identical and controlled conditions, than there isn't an appreciable difference between those two lenses. Excuses need not apply.

There's one last consideration that being the law of diminishing returns. If one concludes that the FA31 is the over all better lens, that relatively marginal increase in optical quality comes at a heavy premium. No doubt some people will say it is well worth 2.8 times more money than the DA40 while others will conclude that's absurd.

Photography seems to polarize people as much religion or politics. The zealots are often as fanatical and short sighted, but in the end you must decide what is right for you and be happy with the choice you make. If can do that you won't be bothered so much by what other people think or say.
05-23-2011, 06:02 AM   #235
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QuoteOriginally posted by JHD Quote
9mm isn't enough variation to say one needs one or the other focal lengths, as most advocates who wax eloquently about the merits of prime lenses fancy this notion of "zooming with your feet".

More to come later today.
In many cases that is true. However, it tight situations whether it is indoors or the photog is jammed in between something and can't back up or move forward, it can be the difference in framing everything into the shot.
05-23-2011, 07:08 AM   #236
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QuoteOriginally posted by JHD Quote
In conclusion one has to consider the possibility sample variation. Perhaps the DA40 belonging to mccarvindh is much sharper copy than the copy of belonging to sjwaldron? And perhaps the FA31 belonging to sjwaldron is better than the copy belonging to mccarvindh? Speculation yes, but plausible as it is well known that copies the same lens can vary from copy to copy.

Another thing to consider is focus accuracy of the "tests". If the focus is out by a few millimeters, you will start to see degradation of fine detail.
Lens testing is something that a lot of people try, and a lot of people fail at, and can sometimes come up with wrong conclusions because of it.
05-23-2011, 07:22 AM   #237
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QuoteOriginally posted by Wheatfield Quote
Another thing to consider is focus accuracy of the "tests". If the focus is out by a few millimeters, you will start to see degradation of fine detail.
Lens testing is something that a lot of people try, and a lot of people fail at, and can sometimes come up with wrong conclusions because of it.
I could not agree more. It is significantly more difficult to run a properly controlled test to compare two lenses that most people would imagine.
05-23-2011, 10:54 PM   #238
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"9mm isn't enough variation"

yes, actually, it is. and the closer you are to the wide end, the more it matters.

the difference between the 70mm and the 77mm for example, is only 7mm, translating to equivalent FsOV of 105mm and 116mm (or so) - both comfortably in the short-telephoto camp.

the difference between a 15mm lens and a 24mm lens in FF terms is astronomical, the difference between superwide and ultrawide. in the former, you'd get your feet in the frame when shooting Portrait format. yes, the 'crop factor'/equivalent FOV phenomenon reduces this severity on an APS-C dSLR.

i stand by what I said: the 40mm DA = 60mm on APS-C = a 'nothing' focal length. probably why it's a little bit good at everything and not really stellar for one specific application. if you're a generalist - enjoy!

i just know that focal length serves no purpose for me, and has little congruence with how my eyes see things. maybe it's cos i cut my teeth with film and primes and am used to seeing in 'three fields' - wide, 'normal' (my 'normal' is slightly wide...) and short tele, as that's what i got used to carrying around with me, three good primes.

never bothered with zooms in film days because they were always too big, too slow, and generally of inferior quality. quality is up today, but they're still too big/too heavy, too indiscreet.
05-23-2011, 11:18 PM   #239
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QuoteOriginally posted by zuikoholic Quote
"9mm isn't enough variation"

yes, actually, it is. and the closer you are to the wide end, the more it matters.

never bothered with zooms in film days because they were always too big, too slow, and generally of inferior quality. quality is up today, but they're still too big/too heavy, too indiscreet.
Point taken at the wide end - but on APS-C if 9mm matters between 31 and 40, that is going to depend on the individual. I just sold my Sigma 30/1.4 but kept my DA40, so I'm well aware of the difference 9/10mm off of 40 makes. Now if you prefer primes to zooms, you're going to be packing a whole lot of lenses at that rate. Not very practical or convenient, especially given the quality of zooms now a days.
05-24-2011, 12:01 AM   #240
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DA 40 is neither fish nor fowl. I was considering purchasing it for a while, then realised my only attraction lay on how thin it was, and gave up on the idea.
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