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01-27-2014, 08:53 AM - 1 Like   #1
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Why isn't my lens as sharp as it could be?

Cross posted from a question in the 18-135 thread.

QuoteOriginally posted by mee Quote
Yes. Actually, I own this lens.

Even stopped down to f/5.6 mine doesn't seem to behave like the sharper images in this gallery.. it is closer to the upper middle in sharpness if there was a level between the really sharp images listed here and the really soft. Which, after seeing some really soft series of images in this thread followed by really sharp, led me to my question.. how many of these are truly the lens and how much is actually PP cleanup for the limitations of the lens? Any PP work gives an inaccurate view of any lens if it is rather involved in a thread I thought about the natural aspects of the lens in question.
Maybe you should send your lens in for alignment, but first i'd make sure you can't get good images from it.

There are a few assumptions you're making here which are inaccurate. PP doesn't make an image sharper, it makes it look sharper. Here's a recently posted picture.



And a 1:1 crop from from that picture unprocessed.



You could easily argue, this lens isn't very sharp.

The dog may look sharper in the finished image, but that's not the PP bringing out something that isn't there. This was an overcast dull day with not a lot of contrast. SO two things are done to bring up the level of contrast, I add definition, which is in essence micro-contrast, and I use the sliders in levels to adjust the brightest and darkest levels shown so that I use the full palette of my output device. Neither of those things change the level of sharpness. What they do is they increase the amount of distinction emphasizing differences that are actually there but may not be discernible by the human eye. The fact that you can't see them, the way they came off the camera doesn't mean they weren't there. That is the biggest mistake people who don't do PP make. They assume that the camera recorded it the way it was.

In actual fact, one of the reasons I process as quickly as possible, is because I want to remember how it was, and in PP create what I saw at the scene. People tend to think, it's not like the original image because you processed it. That's exactly backwards, most of us PP so that we bring out in the image what we saw in the scene.

Another factor is this image was hand held. Right off the bat, I have no expectation that this image would be razor sharp. That it's as sharp as it is is a testament to Shake Reduction. If I'd thought this could be a gallery print, I would have set up the tripod and done it right. But, I was out for a walk with 3 other people, so that wasn't likely to happen.

Now another couple of images. These shot with an A-400 on a tripod with 2 sec delay. A much brighter day with more natural contrast

The whole image


1:1 pixel peeper- all sharpening turned off.


This image looks much sharper and detailed, but, I had more light, so the original image had more natural contrast. I was shooting on a tripod, and the subject as well had more natural contrast. All those things combined make this a sharper looking image right off the camera. The reason I don't have similar images from the 18-135 is, I rarely shoot it on a tripod, and it's a walk around lens, so the light is often less than perfect.

Here's the DA 18-135 used on a tripod, on a bight sunny day with some contrast in the subject area. Shot at 18mm, so , not even in the lens' comfort zone. And this is a 1:1 crop. All sharpening is turned off. To me, this 1:1 crop looks as good as many hand held images of the un-cropped images, that have been reduced in size and therefore had their sharpness artificially increased. The pine needles are distinct, the curved lines of the broken pottery are lines are clear and smooth.

The scene


1:1 pixel peeper- all sharpening turned off.


My computer monitor is 92 DPI, and this image was taken with a k-5. So This image would look the same quality as it does in the Pixel peeper, printed at 53 inches wide. With a bit of sharpening applied, it would look even crisper than it does as it is now with sharpening turned off.

So brief synopsis

PP gives you an opportunity to opportunity to make the picture look like what you saw at the scene, and bring out detail that may have been present but invisible in the un-processed print. (And that you may have observed when experiencing the scene live.)
IF you are going to look at lens sharpness, you must work from a sturdy tripod with a 2 sec delay. No, ifs, no ands, no butts.
Images taken of high contrast subjects in high contrast lighting situations will look sharper than images taken on dull days without much contrast even taken with the same lens and camera.

Or to be more blunt, if you haven't tested your lens in good light, on a tripod with a 2 second delay, with a subject with decent contrast, you really have no idea how good it is. You might have some idea about how steady your hand is, but that would be the most you could accomplish.


Last edited by normhead; 01-27-2014 at 09:23 AM.
01-27-2014, 09:35 AM   #2
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This is a good representation of a few things. Contrast is a big problem - bumping black levels and contrast as well as tweaking exposure are great ways to get better looking images. Sharpness is going to be an issue with any zoom, but with work you can find the best settings.

Cloudy days with low contrast are always trouble. Be satisfied with what you get on days like that...
01-27-2014, 01:18 PM   #3
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Not as sharp as it should be? Let's look at the #1 cause of un-sharpness -- handheld blurring. Even the steadiest photographer has involuntary muscle twitches. Remedy? Set your shutter speed as high as you can. In daylight, always try for 1/1000. Dark and cloudy? Try 1/800. Fight for that high shutter speed. Try to keep the ISO at 400 or lower, and you'll be OK.

Theoretically, it takes 1/1500 second to completely, positively, absolutely eliminate handheld shake blurring. But pros use 1/1000 for sports, and that works for me!

Last edited by jon404; 01-27-2014 at 01:25 PM.
01-27-2014, 01:28 PM   #4
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QuoteOriginally posted by normhead Quote
Cross posted from a question in the 18-135 thread.



Maybe you should send your lens in for alignment, but first i'd make sure you can't get good images from it.

There are a few assumptions you're making here which are inaccurate. PP doesn't make an image sharper, it makes it look sharper. Here's a recently posted picture.



And a 1:1 crop from from that picture unprocessed.



You could easily argue, this lens isn't very sharp.

The dog may look sharper in the finished image, but that's not the PP bringing out something that isn't there. This was an overcast dull day with not a lot of contrast. SO two things are done to bring up the level of contrast, I add definition, which is in essence micro-contrast, and I use the sliders in levels to adjust the brightest and darkest levels shown so that I use the full palette of my output device. Neither of those things change the level of sharpness. What they do is they increase the amount of distinction emphasizing differences that are actually there but may not be discernible by the human eye. The fact that you can't see them, the way they came off the camera doesn't mean they weren't there. That is the biggest mistake people who don't do PP make. They assume that the camera recorded it the way it was.

In actual fact, one of the reasons I process as quickly as possible, is because I want to remember how it was, and in PP create what I saw at the scene. People tend to think, it's not like the original image because you processed it. That's exactly backwards, most of us PP so that we bring out in the image what we saw in the scene.

Another factor is this image was hand held. Right off the bat, I have no expectation that this image would be razor sharp. That it's as sharp as it is is a testament to Shake Reduction. If I'd thought this could be a gallery print, I would have set up the tripod and done it right. But, I was out for a walk with 3 other people, so that wasn't likely to happen.

Now another couple of images. These shot with an A-400 on a tripod with 2 sec delay. A much brighter day with more natural contrast

The whole image


1:1 pixel peeper- all sharpening turned off.


This image looks much sharper and detailed, but, I had more light, so the original image had more natural contrast. I was shooting on a tripod, and the subject as well had more natural contrast. All those things combined make this a sharper looking image right off the camera. The reason I don't have similar images from the 18-135 is, I rarely shoot it on a tripod, and it's a walk around lens, so the light is often less than perfect.

Here's the DA 18-135 used on a tripod, on a bight sunny day with some contrast in the subject area. Shot at 18mm, so , not even in the lens' comfort zone. And this is a 1:1 crop. All sharpening is turned off. To me, this 1:1 crop looks as good as many hand held images of the un-cropped images, that have been reduced in size and therefore had their sharpness artificially increased. The pine needles are distinct, the curved lines of the broken pottery are lines are clear and smooth.

The scene


1:1 pixel peeper- all sharpening turned off.


My computer monitor is 92 DPI, and this image was taken with a k-5. So This image would look the same quality as it does in the Pixel peeper, printed at 53 inches wide. With a bit of sharpening applied, it would look even crisper than it does as it is now with sharpening turned off.

So brief synopsis

PP gives you an opportunity to opportunity to make the picture look like what you saw at the scene, and bring out detail that may have been present but invisible in the un-processed print. (And that you may have observed when experiencing the scene live.)
IF you are going to look at lens sharpness, you must work from a sturdy tripod with a 2 sec delay. No, ifs, no ands, no butts.
Images taken of high contrast subjects in high contrast lighting situations will look sharper than images taken on dull days without much contrast even taken with the same lens and camera.

Or to be more blunt, if you haven't tested your lens in good light, on a tripod with a 2 second delay, with a subject with decent contrast, you really have no idea how good it is. You might have some idea about how steady your hand is, but that would be the most you could accomplish.
Thanks Norm!

01-27-2014, 01:36 PM   #5
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Oh norm... did we really needed to see a crop on that dog's "end"!?
It kind of looks muddy, not sharp
01-30-2014, 02:12 AM   #6
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QuoteOriginally posted by mrNewt Quote
did we really needed to see a crop on that dog's "end"!
Your supposed to be looking at the head end of the other one.
01-30-2014, 06:31 AM   #7
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QuoteOriginally posted by kerrowdown Quote
Your supposed to be looking at the head end of the other one.
Way too distracting to just ignore it
01-30-2014, 08:16 AM   #8
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Original Poster
QuoteOriginally posted by mrNewt Quote
Oh norm... did we really needed to see a crop on that dog's "end"!?
It kind of looks muddy, not sharp
Sorry, didn't mean to get you all excited...

01-30-2014, 08:57 AM   #9
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Your initial post exemplifies your point Norm. I've seen posters call a lens soft because of poor exposures, camera settings, bad technique, poor processing, etc, but some lenses really are defective. Did mee check his lens for AF accuracy and centering? My 18-135mm needed +10 AF Adjust before I sent it back for calibration.
01-30-2014, 09:09 AM   #10
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QuoteOriginally posted by audiobomber Quote
Your initial post exemplifies your point Norm. I've seen posters call a lens soft because of poor exposures, camera settings, bad technique, poor processing, etc, but some lenses really are defective. Did mee check his lens for AF accuracy and centering? My 18-135mm needed +10 AF Adjust before I sent it back for calibration.
I'd never say don't send a lens back... I'm convinced a lot of lenses are damaged in shipping... I'd just say make sure it's not working first. As a caveat to that I'd add, don't order a lens until you have time to test it, test it thoroughly the first week you have it, and return it while you can still return it over the counter ( first 7 days I believe in Ontario) if it isn't performing properly. I've driven a couple hundred Kms to get a lens back to Henry's before the deadline... I don't want a lens that came defective and was repaired, I want a lens that is the same as it was when it left the factory and meets factory spec.

Last edited by normhead; 01-30-2014 at 10:52 AM.
01-30-2014, 09:37 AM   #11
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QuoteOriginally posted by normhead Quote
I don't want a lens that came defective and was repaired, I want a lens that is the same as it was when it left the factory and meets factory spec.
I've done both. I sent the 18-135 back with instructions to repair, not replace, because aside from calibration it was a really good copy. The first DA*300 I got was out of calibration. I insisted on a new lens because I didn't trust the SDM on the first one.
01-30-2014, 09:47 AM   #12
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QuoteOriginally posted by audiobomber Quote
I've done both. I sent the 18-135 back with instructions to repair, not replace, because aside from calibration it was a really good copy. The first DA*300 I got was out of calibration. I insisted on a new lens because I didn't trust the SDM on the first one.
If I'm going to get a new repaired lens, I'll want it a refurb prices. I can see why you kept your lens though if it was just a minor alignment. If it was otherwise good, you could get worse in your next copy. If it was de-centered... I wouldn't trust them to fix that. I'd do an over the counter replacement.

Last edited by normhead; 01-30-2014 at 10:52 AM.
01-30-2014, 10:45 AM   #13
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QuoteOriginally posted by normhead Quote
If I'm going to get a new repaired lens, I'll want it a refurb prices. I can see why you kept your lens thought if it was just a minor alignment. If it was otherwise good, you could get worse in your next copy. If it was de-centered... I wouldn't trust them to fix that. I'd do an over the counter replacement.
There were a few people showing some awful 18-135mm photos at the time. No way I was giving up my good one. I think QC has improved markedly since the launch.
02-01-2014, 11:49 PM   #14
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Are zooms more susceptible to shock damage than primes?
02-02-2014, 07:56 AM   #15
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Actually I think it's quite sharp already. Lighting plays an important role IMO. I'm using a 18135 and image quality isn't that great as 16-50/sigma 17-50 but it's very great for such a price. Try not to pixel-peep - it will only make your photography journey more painful.
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