bad copy of lens? - DPChallenge Forums

Olympus 12-40mm f/2.8 Pro

01/30/2013 06:20:41 PM · #1

I recently picked up a Nikon 16-35mm f/4 to go with my d800. I heard great reviews about it online, and sample images seemed to confirm that it was a very sharp lens.

However, I have been relatively disappointed with mine so far. I'm concerned that the lens may have a decentering issue; it is not very sharp except in the absolute middle, and to me it seems noticeably softer on the right side.

Am I just going nuts?

Here is a test shot I took. I made sure the camera was completely perpendicular to the wall, and shot it on a tripod, at f/4 at 16mm. You can see the bricks are much softer on the right side than the left side, and the sharpness really isn't
there in most of the shot.

Is this normal for a lens of this type? Do I have a bad copy? Would this kind of thing be covered by warranty?

edit: make sure you look at the full sized image when checking this out.

Message edited by author 2013-01-30 18:21:03.

Ann

Olympus OM-D E-M1

01/30/2013 07:35:38 PM · #2

It's not really that easy to tell on an image that's been downsampled this much but I'll ask a couple of questions, and maybe you can work it out for yourself.

Did you use the autofocus, or focus manually using live view? The lens may be basically fine, but it needs an auto fine tune adjustment. If a brand new, state of the art AF-S lens needs a big auto fine tune adjustment, I might still return it though, especially if your other lenses don't need similar adjustments. If all of your lenses need auto fine tune adjustments in the same direction, it could be your body.

1/15 is a pretty unforgiving shutter speed. Did you test it with a faster or slower shutter speed?

Is it at least as sharp as your 50 at f/4? How does it look at f/5.6? At different focal lengths? The 16-35 is supposed to be quite sharp. If you're sure it's properly focused and you don't have any camera shake, and it isn't at least as sharp as your 50 at the same aperture settings, I'd return it and try another.

01/30/2013 07:37:59 PM · #3

Seems a tad softer on the LEFT side, if anything, to me. Pretty even, really. Ultra-wides are NEVER tack sharp edge-to-edge wide open. Just isn't possible. Be realistic. Show us the same thing at f/8, and let's see.

In real-world usage scenarios, the degree to which you're losing sharpness isn't going to be an issue. You're only going to shoot it wide-open hand-held and in very dark situations, if ever. Speaking for myself, I don't think I've EVER used my 16-35mm f/2.8L at either 2.8 OR 4.0 yet... But it's VERY clean at 5.6 or 8...

I must say, that's a LOT of barrel distortion you're showing us here...

01/30/2013 07:40:48 PM · #4

Originally posted by Ann:

It's not really that easy to tell on an image that's been downsampled this much but I'll ask a couple of questions, and maybe you can work it out for yourself.

Ann, open it up again and click on "view full sized image" at the bottom of the list on the left; you can pixel-peep it there. Be sure to check your cursor when the image is done downloading: if there's a + sign in it, then you have one more level to go.

01/30/2013 07:52:06 PM · #5

Thanks for the response, guys. I actually do have a sample of what it looks like at f8:

again, to my eye, the whole image seems softer on the right side. regardless, it seems really really soft overall, especially for an aperture of f8. only the very centers seem to have any reasonable sharpness. is this lens just supposed to be like this?

fyi, im zooming in and looking at the treeline, which i made pass through the center of the image.

Message edited by author 2013-01-30 20:15:58.

01/30/2013 08:10:42 PM · #6

Originally posted by LanndonKane:

...again, to my eye, the whole image seems softer on the left side. regardless, it seems really really soft overall, especially for an aperture of f8. only the very centers seem to have any reasonable sharpness. is this lens just supposed to be like this?

fyi, im zooming in and looking at the treeline, which i made pass through the center of the image.

On the FIRST one you said it seemed "noticeably softer on the right side", on this one you say "again, to my eye, the whole image seems softer on the left side", so that's different right there. Plus, the left side on this portrait image is the TOP side on the horizontal image...

Curiously, on THIS image the foreground details, left and right, are quite sharp. The pond-horizon IS softer at the edges than at the center. I don't know where you were focused at, exactly, but I know where your focus IS, now, and it's damned near at your feet. So you can't expect the horizon to be sharp at f/8, and when it's NOT sharp then any deviation FROM sharp (at the edges) will be more visible.

You may have a front- or rear-focus issue here...

01/30/2013 08:16:47 PM · #7

Originally posted by Bear_Music:

Originally posted by LanndonKane:
...again, to my eye, the whole image seems softer on the left side. regardless, it seems really really soft overall, especially for an aperture of f8. only the very centers seem to have any reasonable sharpness. is this lens just supposed to be like this?

fyi, im zooming in and looking at the treeline, which i made pass through the center of the image.

On the FIRST one you said it seemed "noticeably softer on the right side", on this one you say "again, to my eye, the whole image seems softer on the left side", so that's different right there. Plus, the left side on this portrait image is the TOP side on the horizontal image...

Curiously, on THIS image the foreground details, left and right, are quite sharp. The pond-horizon IS softer at the edges than at the center. I don't know where you were focused at, exactly, but I know where your focus IS, now, and it's damned near at your feet. So you can't expect the horizon to be sharp at f/8, and when it's NOT sharp then any deviation FROM sharp (at the edges) will be more visible.

You may have a front- or rear-focus issue here...

made a mistake in my last post, i meant to say right when i said left. in both images. the focus seems softer on the right side. (edited it to avoid future confusion)

i didnt even think about the portrait vs. landscape thing. hmmmm.

also, i was sure i focused on the horizon. maybe there is some focus issue thing going on.

Message edited by author 2013-01-30 20:19:33.

01/31/2013 10:12:38 PM · #8

Last query from me, guys.

Here is the exact same scene at f/13

to me, there is still some definitely softness on the right side, even though things are looking much better (it looks like a "smearing", almost).

Further, some of the corners are weaker than others. they're not all the same.

is this all normal for a lens of this type? based on reviews of this lens, one of the highlights is supposed to be superb edge to edge sharpness, except in the extreme corners. things are supposed to be especially sharp at 16mm, with not much variation at all in MTF accross the frame.

Since i'll be out of the country for 5 months soon (with my lens and camera), I want to make sure everything is good, or, take care of the problem before I leave, before the return policy expires.

EDIT: to show that the right side is softer at f4, you can toggle between the f13 version and the f4 version. The sharpness changes dramatically when going from f4 to f13 on the right side (i.e. gets much sharper), while the left side doesn't change nearly as much (i.e. was sharp to begin with)

Message edited by author 2013-01-31 22:19:56.

01/31/2013 10:22:02 PM · #9

You're being really nit-picky. That's actually quite good for an ultrawide. And f/13 is borderline for stopping down too MUCH. Your sweet spot at 16mm will be somewhere between f/11 and f/8 I imagine...

Basta

Nikon D4

01/31/2013 10:27:14 PM · #10

not to ad fuel, but you do know about this D800 left focus?

01/31/2013 10:35:12 PM · #11

Originally posted by Bear_Music:

when you spend your entire savings, gotta make sure things work properly. thanks for the feedback though.

01/31/2013 10:35:45 PM · #12

Originally posted by Basta:

not to ad fuel, but you do know about this D800 left focus?

yeah i did, i think it's just the earlier models. didn't test mine out scientifically, but it seems okay to me.

01/31/2013 11:20:57 PM · #13

Originally posted by LanndonKane:

Originally posted by Bear_Music:
You're being really nit-picky. That's actually quite good for an ultrawide. And f/13 is borderline for stopping down too MUCH. Your sweet spot at 16mm will be somewhere between f/11 and f/8 I imagine...

when you spend your entire savings, gotta make sure things work properly. thanks for the feedback though.

I didn't mean to put you down, I was trying to reassure you. If you have any doubts, just return it and ask for a new copy.

Olympus 12-40mm f/2.8 Pro

01/31/2013 11:38:49 PM · #14

Originally posted by Bear_Music:

Originally posted by LanndonKane:

Originally posted by Bear_Music:
You're being really nit-picky. That's actually quite good for an ultrawide. And f/13 is borderline for stopping down too MUCH. Your sweet spot at 16mm will be somewhere between f/11 and f/8 I imagine...

when you spend your entire savings, gotta make sure things work properly. thanks for the feedback though.

I didn't mean to put you down, I was trying to reassure you. If you have any doubts, just return it and ask for a new copy.

no offence taken. my thanking you for the feedback was very sincere, as i am now quite reassured. you seem do a lot of wide angle stuff, so you would definitely know about this stuff.

also, just realized i'm past the 10 day return policy, so any dealing with this would have to be through warranty, which i dont want to dooooo. so ill probably just stick with it.

Message edited by author 2013-01-31 23:39:37.

Ann

Olympus OM-D E-M1

02/01/2013 11:57:40 AM · #15

I thought I posted this after Bear told me how to click through to see the whole image, but....

It looks fine to me. The 16-35 is indeed one of Nikon's sharper lenses, but the D800 challenges even the best lens. The shots you're showing are at least as sharp as any lens I have in my bag.

I can't do the math, but I have Thom Hogan's D800 book, and he says that on the D800, diffraction starts kicking in right around f/5.6. What I see in my own shots of brick walls is that f/5.6 and f/8 look fine. At f/11, I start seeing noticeable softness from diffraction, and f/16 is basically unusable unless I downsample a lot. So I would guess that at f/13, the softness you're seeing is diffraction softness.

02/01/2013 12:20:22 PM · #16

Originally posted by Ann:

makes sense. diffraction softness i don't mind, it cleans up pretty well with unsharp masking. it was the smearing at the the edges that was bugging me, especially that it seemed to be more to the right side, but if that's all normal than i am happy.

Neil

Fujifilm X-T30

02/01/2013 05:21:06 PM · #17

I bought the 16-35 in late December and I haven't run any tests (nor had a chance to used it much) but as I recall, my test shots looked sharper ... I am using it on a D600 though.

If it's not too cold or wet, I can try a brick wall test for you this weekend as a comparison (though I'm not sure I have a brick wall wide enough here...)

I'll also do the same with my D7000 and my Sigma 10-20. Should be a good fight.

As Robert said, I noticed the sharpness on the near shoreline...that looks to me where the focus was set for whatever reason!

02/01/2013 05:26:10 PM · #18

Originally posted by Neil:

thanks a lot Neil, that would be helpful. I can downsample
these images to match the resolution of the D600. Looking
at other online reviews and images, I imagined it to be sharper
than this.

Neil

Fujifilm X-T30

Canon EF 16-35mm f/2.8L USM

02/01/2013 05:59:48 PM · #19

Looked at what I had shot so far...only had the lens out for two quick jaunts, mostly just to try it.

I uploaded two samples converted from RAW using LR but just at default settings...exported without sharpening.

Both hand held quickies.

I can see some CA and fuzzy corners...but the street shot is at F4.5 and seems pretty good to me.

The bike path shot was focused on the building, as I recall, and the tree on the right looks pretty good to me.

But I'll try to find a wall this weekend. :) It would be nice to give my lens a proper test anyway.

You need to click on view full size image to see the unreduced version...

BTW, the street shot was shot in RAW+JPEG (both the uploads are from RAW). But if I look at the JPEG I don't think the Nikon processing is doing the file any favors in edge sharpness...seems softer than the unsharpened RAW. Perhaps that's part of your issue?

Patrick_R

Canon EOS-60D

02/01/2013 06:15:27 PM · #20

Wow.... that corner vignetting....

02/01/2013 06:16:54 PM · #21

Thanks so much for these Neil. I'll check them out
as soon as I get to my computer, and am looking forward to the brick
test to confirm my suspicions.

No, I don't shoot jpeg, only ever shoot RAW.

Neil

Fujifilm X-T30

02/01/2013 07:45:37 PM · #22

Originally posted by Patrick_R:

Wow.... that corner vignetting....

Part of that might be the fact that I had my polarizer on...not ultrathin (B+W + Pro Kaessaman, or however it's spelled)

Sigma 12-24mm f/4.5-5.6 EX Aspherical DG HSM for Nikon

02/02/2013 12:58:49 AM · #23

Checked out those sample shots. They look beautiful, and the sharpness is wonderful. Nothing like what I can get from mine.

Here is another sample of mine:

To me, this is drastically less sharp. There is quite bad smearing and blur at the edges, even in the foreground (where I believe the focus is). I did not see any of this in Neil's image.

Keep in mind this was taken at f 7.1, nearing what is supposed to be the perfect aperture for this lens. It was also taken with a tripod at a pretty fast shutter speed.

Message edited by author 2013-02-02 00:59:42.

bohemka

Nikon D700

02/02/2013 01:19:14 AM · #24

Looks good to me. You do realize there's a puddle in the foreground that's causing the lack of clarity. I don't believe a lens has been made that will combat that.