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02-13-2018, 05:45 PM   #16
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QuoteOriginally posted by mikesbike Quote
I agree with stillshot2. You say you focused on the eye. In the second example among those presented, I find her eye to be quite sharp. And these are not posted at full size resolution. At f/2 there will be a shallow DOF, so not much of the scene will be in sharp focus. Of course, both the FA 35mm f/2 and the 31mm f/1.8 Limited, although capable of such sharp results wide open (unusual, especially in a fast lens!), both lenses are still not at their very best wide open. I don't see anything wrong based on what you show here. It is certainly not the way to do a definitive lens test, but as a quick check it passes the test easily.
Haha you basically put into words exactly what I was thinking but being to lazy to do. Also, sometimes ultimate sharpness isn't the best thing for portraits, which is where wide open apertures are often used, so having a lens that is slightly softer wide open can be an advantage in this case as to not magnify skin imperfections. My Super Takumar 50mm f1.4 is a perfect example of this. Dreamy at f1.4 yet still reasonably sharp and then tack sharp at f2. I used to be a pixel peeper but these days I seem to value more how an image looks as a whole and start to worry less about what pixels could have been resolved.

02-13-2018, 09:11 PM   #17
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QuoteOriginally posted by mikesbike Quote
And these are not posted at full size resolution.
They are if you go full-screen and use the interface. I found it easier to simply download and view them side-by-side using my usual tools. The downloaded images also came with the EXIF intact. #4 is the only one of the five where the right eye (subject's left) is in focus.


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02-14-2018, 03:25 AM   #18
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Thank you all very much for your answers! I really appreciate your support and willingness to share your expertise with me.

So I took a tripod today and followed the instructions given her, shot a series of pictures from F2.0 - F 3.5.
Uploaded the RAW-Files again to my Dropbox.

The first shot is shot using live view, the second one the viewfinder.

I'm a little bit disillusioned... I knew that the FA35 2.0 isn't a FA31 1.8 Limited. But from my jugement I'd say it starts to be (really) sharp (at the center) from f3.2 on. (maybe f2.8). As someone has mentioned (interesting point of view) maybe it's not that important to focus on sharpness first and foremost. However, when using a prime I'd expect some kind of sharpness.
You guys seem to struggle as well how to judge it. Some say it's good, others view it as rather lagging behind...

Btw. I'd say that both versions (liveview/viewfinder) look pretty much the same. Would you agree with my conclusion when I say that this indicates that there's no really back or front focus? Rather a soft copy? Have to see whether focus adjustment can make things better.

Well, maybe you'll disagree completely and say that it's sharp.

Pictures are located here again (look for the newer ones) Dropbox - FA35 2.0

What's your take on the new ones?

Thank you in advance for all your efforts!

P.S. Again, focus on the right eye (objet's left eye)

---------- Post added 02-14-2018 at 11:41 AM ----------

For comparison. My FA43 1.9 Limited:

Dropbox - FA43 1.9
02-14-2018, 10:27 AM   #19
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This time you seem to be as baffled as I am

02-14-2018, 12:37 PM   #20
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QuoteOriginally posted by zeitlos Quote
P.S. Again, focus on the right eye (objet's left eye)
I just took a quick look at IMGP4226.DNG (f/2.0, live view). The photo is definitely soft, but the EXIF indicates contrast-detect AF (Automatic Tracking ), with no points in focus.

I am not confused.

Again...manual focus, magnified live view*. Our intent is to test the lens, not the AF system. FWIW, the AF spot for both PDAF and CDAF is too large for fine focus purposes and is best set to use center spot or equivalent so you know where the AF is set to.


Steve

* In the English user guide, this is on page 109 "Focusing Using Live View". In short, put the AF switch in the MF position and hold down the "OK" button to magnify the view. I believe full sensor resolution (1:1 pixel-to-pixel mapping, 100%) is at 6x on the K-30.

Last edited by stevebrot; 02-14-2018 at 12:44 PM.
02-14-2018, 12:44 PM   #21
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Thanks Steve! Seems as if I have to adjust again.

However, what's puzzling. Why does the FA43 deliver under same conditions with same settings?
02-14-2018, 12:51 PM   #22
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QuoteOriginally posted by zeitlos Quote
However, what's puzzling. Why does the FA43 deliver under same conditions with same settings?
I don't know...different lens, perhaps? We are evaluating your FA 35/2 and it may well have a problem. Manual focus on the doll's eyelashes should be diagnostic. I suggest incrementing your aperture in full stops maxing at f/8 (f/2, f/2.8, f/4, f/5.6, f/8). Maximum center resolution should come at about f/4.


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02-14-2018, 12:55 PM   #23
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QuoteOriginally posted by stevebrot Quote
I don't know...different lens, perhaps? We are evaluating your FA 35/2 and it may well have a problem.
Sorry to sound like a teacher. That reads a little harsh


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02-14-2018, 01:57 PM   #24
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And this is all still on the K-30 right?
02-14-2018, 02:05 PM   #25
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QuoteOriginally posted by stevebrot Quote
Sorry to sound like a teacher. That reads a little harsh


Steve

No problem, Steve. I appreciate your comments!


Stefan

---------- Post added 02-14-2018 at 10:06 PM ----------

QuoteOriginally posted by UncleVanya Quote
And this is all still on the K-30 right?
Yes, everything K-30. FA35 and FA43 Limited.
02-14-2018, 03:21 PM   #26
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QuoteOriginally posted by zeitlos Quote
Yes, everything K-30. FA35 and FA43 Limited.
Understood. As indicated different lenses can behave differently but I would expect the FA 43 1.9 to be about the same difficulty to focus as the FA 35 f/2.

Earlier I mentioned that the FA 35 outperformed the FA 31 when wide open. (And yes that means it is slightly stopped down compared to both, not claiming otherwise) It also supposedly outperforms the FA 43 wide open. Here are example tests that show this:
Pentax SMC-FA 35mm f/2 AL - Review / Test Report - Analysis
Pentax SMC-FA 31mm f/1.8 AL Limited - Review / Test Report - Analysis
Pentax SMC-FA 43mm f/1.9 Limited - Review / Test Report - Analysis

Granted these are just two samples not a cross section and they don't say if your copy is up to the standards tested.

Also note that the border performance of the FA 35 is quite good. And by f/2.8 all of the lenses are cooking and all peak by around f/4 - all of these tests I think are on crop (which the K-30 obviously is).

My own copy is manual focus only - the AF died in a severe drop accident. I had the lens worked on but they couldn't save the full function. She behaves like an M lens with a short throw focus ring.
02-15-2018, 12:36 AM   #27
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Alright, am I jumping to conclusions when I say that my copy seems to have a problem or at least doesn't meet demands as far as I can expect a certain image quality from it?

I will do some more testing but actually I assume that it's rather soft. Next question would be if one (service) could do something against it.
02-15-2018, 02:51 AM   #28
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QuoteOriginally posted by zeitlos Quote
Alright, am I jumping to conclusions when I say that my copy seems to have a problem or at least doesn't meet demands as far as I can expect a certain image quality from it?

I will do some more testing but actually I assume that it's rather soft. Next question would be if one (service) could do something against it.
It's still too hard to tell from your photos if the 35mm lens is actually in focus or not. I recommend a flat subject, such as a focus test chart taped to the wall and repeat testing comparing 100% magnified live view manual focus to autofocus, with camera on a sturdy tripod, image stabilization off, and 2 second shutter delay. Perhaps the 35mm lens needs to be calibrated to your camera body? There are many factors to consider but in the end if your 31mm worked better for you under your average shooting conditions then you probably shouldn't have gotten rid of it since the cheaper 35mm can't really be expected to replace it just like a Mazda Miata can't replace a Porsche 911.
02-15-2018, 12:15 PM   #29
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QuoteOriginally posted by stillshot2 Quote
It's still too hard to tell from your photos if the 35mm lens is actually in focus or not. I recommend a flat subject, such as a focus test chart taped to the wall and repeat testing comparing 100% magnified live view manual focus to autofocus, with camera on a sturdy tripod, image stabilization off, and 2 second shutter delay. Perhaps the 35mm lens needs to be calibrated to your camera body? There are many factors to consider but in the end if your 31mm worked better for you under your average shooting conditions then you probably shouldn't have gotten rid of it since the cheaper 35mm can't really be expected to replace it just like a Mazda Miata can't replace a Porsche 911.
I agree - but I will also say having shot both - the difference isn't night and day like this.



02-15-2018, 12:32 PM   #30
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QuoteOriginally posted by zeitlos Quote
Next question would be if one (service) could do something against it.
Things that might cause softness (assuming it really is soft and not just out of focus):
  1. Internal fungus
  2. Hazing resulting from amateur cleaning attempt
  3. Badly scratched rear element (think sandpaper)
  4. Incredibly bad decentering
  5. Improper reassembly after amateur service attempt
  6. Elements not properly positioned due to physical damage (dropped)
All but the last three would be readily seen by checking the lens internals in a dim room with a bright penlight (torch) and magnifier loup. (Shine light on and through the lens from various angles while looking though from both ends.)


Steve
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