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02-26-2010, 08:05 PM   #1
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FA43mm too soft?

Lately I have come across several thread where people were either looking for wide-open shots with the FA Limited lens or were saying that the FA43 was too soft or something similar. Rather than track down all the individual posts, I thought I could create a new thread that could be referred to when needed.

I took three shots with the FA43 at three apertures. I used a tripod and release cable but my target was not completely asleep so there still might have been a bit of movement. The shots are at ISO 100 and have been run through my usual PP but without all the sharpening I might otherwise do. There do seem to be slight exposure differences but that is life.

The subject is off-centre so sharpness is not exactly optimal. Nonetheless, I think any of these are quite usable. There is a reason I don't obsess over sharpness when using the FA Limiteds.


FA43 at f/4.0




FA43 at f/2.8




FA43 at f/1.9



02-27-2010, 01:22 AM   #2
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QuoteOriginally posted by rparmar Quote
Lately I have come across several thread where people were either looking for wide-open shots with the FA Limited lens or were saying that the FA43 was too soft or something similar. Rather than track down all the individual posts, I thought I could create a new thread that could be referred to when needed.

I took three shots with the FA43 at three apertures. I used a tripod and release cable but my target was not completely asleep so there still might have been a bit of movement. The shots are at ISO 100 and have been run through my usual PP but without all the sharpening I might otherwise do. There do seem to be slight exposure differences but that is life.

The subject is off-centre so sharpness is not exactly optimal. Nonetheless, I think any of these are quite usable. There is a reason I don't obsess over sharpness when using the FA Limiteds.
I think there are a lot of people out there with little or no understanding of optics and depth of field.
They see an image with a very shallow depth of field and brand the optic "soft", or they don't understand that no lens is at it's best wide open, and so brand it as soft because it isn't perfectly sharp at every stop.
02-27-2010, 01:49 AM   #3
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I own a silver FA 43mm and had a black FA 43mm earlier. Never had an issue with regards to sharpness with this lens.
Now talk about purple fringing and that's an altogether different issue. My earlier copy had pretty bad purple fringing wide open.
02-27-2010, 03:29 AM   #4
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Its a great lens and agree with all above

nice photos and wonderful examples shown rparmar and a good idea re this thread

cheers

Neil

02-27-2010, 05:25 AM   #5
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QuoteOriginally posted by Wheatfield Quote
I think there are a lot of people out there with little or no understanding of optics and depth of field.
They see an image with a very shallow depth of field and brand the optic "soft", or they don't understand that no lens is at it's best wide open, and so brand it as soft because it isn't perfectly sharp at every stop.
You just have to look at these photos compared to, say, an FA 50 f1.4 wide open to see the difference. You are right that some people confuse narrow focus plane with soft -- something is sharp, it just isn't what they wanted, but when I take a photo with FA 50 wide open, nothing seems particularly sharp.

Anyway, FA 43 looks pretty good to me!
02-27-2010, 05:56 AM   #6
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I love my FA43. The pictures it takes make me look like I know what I am doing.
02-27-2010, 06:24 AM   #7
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QuoteOriginally posted by Rondec Quote
You just have to look at these photos compared to, say, an FA 50 f1.4 wide open to see the difference. You are right that some people confuse narrow focus plane with soft -- something is sharp, it just isn't what they wanted, but when I take a photo with FA 50 wide open, nothing seems particularly sharp.
If I had the FA50 I could have compared it at a similar aperture, say f/2. As it was, I considered comparing the K 50/1.2 but didn't for two reasons.

1. The kitten always wakes up and moves when I get out my camera.

2. I know for sure the K50 is loads softer... I simply do not need to do this exercise.
02-27-2010, 08:19 AM   #8
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.

I suppose that if someone looked at the following shots out of the camera, they
might say it's 'soft' wide open, when in fact that DOF is so small that only a very
small portion of the frame is sharp - that's the lens performing as it should:

(all 43ltd wide-open)








02-27-2010, 09:36 AM   #9
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The other point to be made is that "softness" can be used artistically. Where one places focus and how much depth of field to dial in is an important part of photographic practice. Just compare the crystal clear infinite depth of field favoured by some landscape photographers (likely using field cameras so they can use front tilt) to the diffuse look that can enhance the attractiveness of models in fashion shoots. I know it's obvious but it deserves to be repeated.

Emphasis on sharpness at all costs ignores all the other characteristics of a lens and reduces photography to a scientific pursuit for accutance. But, don't get me wrong, I'm as picky as anyone when it comes to finding lenses that render accurately. But I am also interested in lenses that render "usefully", where use value lies somewhere on an aesthetic curve I don't think anyone can quantify.

OTOH, one can always add diffusion, blur or fog effects. Some plugins are great at this. Adding detail where there wasn't any to begin with is (nearly) impossible.

P.S. Jay, that second shot is a great example of painterly bokeh and nice use of minimal DOF.
02-27-2010, 10:21 AM   #10
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Well, I couldn't resist. I have now compared three of my normal lenses at a few apertures in order to gather some more concrete data about their performance. I simply set up a bowl of fruit in natural diffuse light from a nearby window, put the K20D on a tripod and shot at ISO 100. The RAW files were imported using Adobe RAW Converter using minimal settings. I boosted clarity +20 added some fill light and increased exposure, since all the shots were underexposed a stop or so. I applied exactly the same settings to each shot from a given lens (they expose differently).

In Photoshop I applied my usual process, which corrects the curve and applies a minimal first-pass sharpening. For the purposes of this test I did not apply the second pass of sharpening that I normally would when outputting for a web image. I also did not correct for contrast, etc. In other words, I could make all of these images look a lot better, and normally would. These images represent the worst the lens should perform at these settings.

I relied on centre spot auto-focus in order to provide a level playing field. (I used trap focus for the manual focus lenses.) The focal point is the centre of the light bulb which, in retrospect, might have been a bit challenging.

This exercise is by no means "scientific" and is of limited applicability. Three notable limitations: it tests only the performance in the centre of each lens, multiple shots should have been run to eliminate focus issues, only one focal distance was tested. Feel free to do your own testing to satisfy yourself that you have the right tools for the job. Me, I'm content that the results conformed to the expectations I've accumulated after months (years) using each lens.



From left to right: Cosina 55mm f/1.2, smc Pentax 50mm f/1.2 (AKA "k"), FA43 Limited f/1.9. The difference in image size comes from the differing focal lengths, as I kept the subject to camera distance static.

These are 100% crops of each lens at f/2.0. But you need to click through to Flickr to actually see the image that large. Once in Flickr, click on "All Sizes" and then select the 2400 x 1200 image.

Go to my Flickr test set to see full frame shots (resized) of each lens wide open and at f/2.0, f/2.8 and f/4.0.
02-27-2010, 11:28 AM   #11
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I have never looked up on the FA43 as soft. It's not THAT sharp wide open, but it's not bad. Maybe it's because people are reading Yoshihiko's resolution tests.

FA 43: 55 wide open, 69 at F2.8 and 87 at F4.
FA 35: 78 wide open, 87 at F2.8 and 98 at F4.
K...30: 69 wide open, 69 at F2.8 and 87 at F4

However, we all know that resolution tests do not tell the whole story.

Kind regards
.lars
02-27-2010, 01:21 PM   #12
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While I'm stockpiling info in this thread, here is a comparison I don't think anyone has yet made on this forum. It came about when I was reading up on Leica glass on SLR Lens Review and noticed that they not only had tested the much-lauded Summilux-R 50mm f/1.4 but the FA43 as well. Both are on APS-C sensors, though of course the tests are not directly comparable due to sensor differences between the Canon and Pentax. Nonetheless I find the results and their interpretation intriguing. I cannot resist seeing how the Pentax stacks up.

For the Summilux the author concludes that:

QuoteQuote:
The lens produced very solid results in the lab. The weakest point was f/1.4, where the lens was very soft around borders and only slightly better in the center.... But once stopped down to f/4, quality improves significantly and you will be able to get great 19in prints - an achievement very few lenses can claim.
Other superlatives are uttered, based on MTF50 figures that range from 32-427 (border to centre) at f/1.8 and 91-613 at f/4. (I won't mention the wide-open figures since the lens smudges detail something fierce.)

According to this table, the FA43 achieves 37-356 at f/1.9. It intrigues me that it is actually sharper than the Summilux exactly where people criticise it the most - the borders. It is also amazing that the lens wide open is more-or-less as good as the Leica stopped down.

But the big surprise is that at f/4 the FA Limited measures 91-688 MTF50 and is better in all respects than the Leica lens! Yet in the summation the author is diffident, waffling on about it being OK here and not so bad there. The conclusion:

QuoteQuote:
Generally speaking, pretty solid results, with wide apertures being the obvious exception.
Shouldn't this be a rousing endorsement? Something along the lines of "exemplary rendering with accuracy on par with the best Leica can offer."

Lens tests may not be everything, but if one is going to use them as the primary standard of comparison, it sure would be nice if they were interpreted fairly.
02-27-2010, 01:30 PM   #13
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Useful thread, if you read reviews on the lens by review sites and users it's very, very common to see "too soft wide open for the price" as a complaint.

Thanks for the comparison from F/4 up.
05-17-2010, 04:18 PM   #14
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The anonymous author of this article found that the FA43 is sharper at f/1.9 than the DA 40/2.8 is wide open. And further, that it is as sharp as the FA 50/1.4 at f/2.0 in the centre (though not the corners).
05-17-2010, 08:22 PM   #15
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We should have more threads like this!

But then you'll have to add "should I get the FA43 or DA40?" stuff.

Then we need a definitive thread for:

DA70 or FA77?
FA50 or DA*55?
...
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