SCREAM... NEW Sigma 70-200 F2.8 and Blurry shots

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/23/2012 10:29:23 PM · #1

Ok I need some big ol help here New Sigma 70-200 F2.8 APO EX DG OS (for myNikon) ...When I shoot this lense @ f2.8 zoomed in or zoomed out, On tripod or hand held, I can't seem to get a in focus image, I've scanned around the shot and no I just didn't miss the focus spot, there is no sharp point on the shot... Exmp. I shot a friend outside tonight focused on her eye,(zoomed in (200mm) to make sure I had dead set on the eye) locked the focus zoomed back out to 70 mm shot... NO point on the image is focused. This on tripod with the OS turned off... Same results with other settings, ie, Os on, zoomed in at 200mm and shot at that, all this at my native ISO 200 on my nikon d90. NOW I had some shots at F6.3 and they are stunning, focus, color, etc everything you'd expect out of this lense.

I could understand if I missed the focus point and something else was in focus, and Yes I understand at F2.8 theres only gonna be a very little in focus... Oh also used AF and manual to see if the AF was off at that apature, but again same results... Now not that I'm going to be shooting a lot at F2.8 BUT ...

What am I doing wrong????? Suggestions????? Thanks so much Katie

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/23/2012 10:31:09 PM · #2

Oh and single point AF area mode

vawendy

Sony Alpha 1

Sony FE 200-600mm f/5.6-6.3 G OSS

06/23/2012 10:40:06 PM · #3

I have absolutely no clue... something should be in focus!!

Is there any sort of gooey coating on either end of the lens?

(Oops, missed that it focused at 6.3)

Message edited by author 2012-06-23 22:46:12.

vawendy

Sony Alpha 1

Sony FE 200-600mm f/5.6-6.3 G OSS

06/23/2012 10:42:57 PM · #4

Does it have a switch on the side for far away vs close up focusing?

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/23/2012 10:46:47 PM · #5

nope, no switch except to turn the OS on off 1 and 3 and AF and manual...

bjoern

Canon EOS-5D Mark III

Canon EF 24-105mm f/4.0L IS

06/23/2012 10:49:45 PM · #6

Originally posted by littlemav:

I shot a friend outside tonight focused on her eye,(zoomed in (200mm) to make sure I had dead set on the eye) locked the focus zoomed back out to 70 mm shot

I don't think that you can expect the focus to stay were it was set when you change the focal distance from the focal distance used when focussing.

But I agree, some part of the picture should be in focus.

What you can do is to take a yard stick, lean it against a wall at an angle, and focus the middle of it. Somewhere there should be a point in focus on the stick. If not, then I would suppose something is wrong with the lens. If the focus point is not where you set it - either further away or closer - you can adjust this with some cameras somehow. Mine is too simple for this, so I don't know any details in general and not for the the D90 in particular.

Message edited by author 2012-06-23 22:51:47.

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/23/2012 10:54:51 PM · #7

I do have several where I did not change the focus distance, with the same result... I am running off to find a yard stick..... OH to make this even better... My friend just bought the same lense (she has a Cannon) and she is having the same problem...

Bear_Music

Samsung Galaxy S21, S21+, S21 Ultra

Sony 24-70mm F4 Vario-Tessar T* FE OSS

06/23/2012 11:22:06 PM · #8

You cannot focus this lens at 200mm then zoom out and still have focus. It won't even be close. You need to refocus every time you zoom. This is normal.

R.

scalvert

Canon EOS-5D Mark III

Canon EF 24-105mm f/4.0L IS

06/24/2012 12:13:42 AM · #9

A constant aperture lens CAN be parfocal. Canon's 24-105 is supposedly parfocal, and their 70-200 f/2.8 lenses are very close. None of Sigma's lenses are, though. As Bear noted, you have to refocus after zooming.

Message edited by author 2012-06-24 00:15:27.

MelonMusketeer

Nikon D7000

Nikon MF 50mm f/1.4

06/24/2012 12:23:20 AM · #10

If the D90 has live view, you can use the tripod and live view to zoom in on the desired focus point with the LCD after you set the lens at the zoom that you want. It's tough to manual focus with fast lenses. The D90 may also have a focusing aid in the lower left of the viewfinder, two green arrows and a dot.
As the other posters said, something should be in focus at wide open aperture.
Have you read the info that came with it? Some AF lenses can be set so that they don't focus close, to make it quicker to focus when shooting moving targets like birds outdoors.
Hopefully it's not a quality control issue with the lens.
ETA, If you are trying to manual focus, make sure that the diopter adjustment is spot on, by using a known accurate lens on the tripod, then adjust the diopter so that you are seeing the focus point correctly.
There is one other question, how much of the image are you looking at to check focus? Some lenses are a lot "softer" than others when shooting wide open, and it shows up looking almost like noise or bokeh when you zoom in to look at a small spot of the original image.
If you can't get it to work, at least you will be all set for the "July Blur Festival" SC. : )

Message edited by author 2012-06-24 00:32:42.

goinskiing

Canon EOS-6D

Canon EF 24-70mm f/2.8L USM

06/24/2012 12:32:22 AM · #11

Originally posted by scalvert:

Interesting, I'll new to test this out for fun.

06/24/2012 02:47:12 AM · #12

I have the previous version of the Sigma 70-200mm f/2.8 EX DG HSM (non OS). It is the sharpest lens I have from f/2.8 to about f/16.
The D90 does not have a "per lens" manual focus adjustment option. Only the DX D300/D300s and the FX D700 on up to the D4 have this feature. You will need a calibration rail to accurately test it (B and H sell many versions) but the yard stick idea will work for now as a test to see back or front focus. I suggest using a large silver metal ruler rather that has inches and milimeter markings, and lean it at 45 degrees away from you in a disappearing line somewhat like looking down a straight section of black top (tar road). Let it auto focus in the middle somewhere. Also check if your diopter in the viewfinder is set to your eye correctly. Test it on a friends Nikon as well.

alexlky

06/24/2012 03:23:49 AM · #13

Originally posted by HarveyG:

How about lighting? Do we need brightly daylight ambient.

06/24/2012 03:51:25 AM · #14

Start there yes and at 70mm, f/2.8, then 70mm f/8 then 70mm f/16 then 70mm f/32. Bright light all on a tripod with Shutter Delay enabled and an IR remote control shutter release indoors to prevent any blur affecting your results. Then run 100mm at the same f/stops and 200mm at the same f stops. Look at your results at 100% on screen. Use single point AF and make sure it focusses at exactly the same spot (not easy). Then use Manual Focus on the 10cm mark on your ruler and try the entire process again. There are many tutorials online if you just take the time to look. What I have written here is a very basic methodoligy but it should tell you that your lens is OOF, needs repair or the camera is front or back focussing. Try two cameras as well with the same lens!

Note also that the machining tolerances on bayonet lens and body mounts are never 100% the same. My D90 will be machined perhaps a few thousands different from yours as will our lenses and this will, albeit infinitesimally, make some differences to AF points. Never mind gearing and use and age.

But it's seldom where lenses fail and AF fails (in bright light). This normally happens at smaller apertures and darker conditions, where lenses hunt or fail to focus. I shoot a fair amount of African wildlife (in the bush) and the best opportunities are golden hour where light is sparse. When the lens hunts, either go Manual Focus or go home :)

If the lens continues to obviously be unsharp it's been dropped or poorly finished and if it is the only lens in your arsenal that does this you can then exclude your body as part of the problem. Take it back to the supplier (Sigma) and either have it calibrated (the lens adjusted) on YOUR body or get a replacement lens and try again. This is not unusual and again the web is full of stories where the owners have had the lens adjusted to suit their bodies. If you own a pro body; D300/D300s, D700, D3, D3s, D3x, D4, D800, D800e you can do the calibration on a per lens basis on the body without leaving home...but you should have a pro calibrator tool.

Edit To add: This is called "AF Fine Tune". On the D300 p327, D300s page 312, D700 page 347

Message edited by author 2012-06-24 04:16:12.

Voigtlander Ultron 21mm f1.8

06/24/2012 04:18:03 AM · #15

Katie, you have a D700, does the Sigma 70-200mm do the same OOF on this body? Are you using Single Point AF?
Look at D700 User Manual Page 347 - AF Fine Tune. The D90 does not have this useful function.

MAK

Leica M Monochrom

06/24/2012 04:52:48 AM · #16

I have owned 2 versions of the sigma 70-200 f2.8. The old one was soft the new one was soft, sent to sigma with body for calibration and came back worse, took it there myself with body and waited while the guy tried 5 or 6 times to set it up right but couldn't, although it got better I still decided to hand it back, the guy said "it's 1/3rd the price of the Canon L so please do not expect L quality".

I ended up with the Canon.

A friend of mine had one of these and it was soft. he was OK with that as it sharpened up nicely in PS, sadly I don't have the time to sharpen every image.

Sorry to hear about these issues for you.

scalvert

Canon EOS-5D Mark III

Canon EF 24-105mm f/4.0L IS

06/24/2012 11:27:59 AM · #17

Originally posted by goinskiing:

Originally posted by scalvert:
A constant aperture lens CAN be parfocal. Canon's 24-105 is supposedly parfocal, and their 70-200 f/2.8 lenses are very close.

Interesting, I'll new to test this out for fun.

I just tried it with a 24-105 f/4L and 70-200 f/4L on the new camera. Both stayed sharp when prefocused and racked to the other end of the zoom scale.

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/24/2012 03:11:10 PM · #18

Well I did the yardstick test, I have 2 D90's and I put the lense on both and did it, exactly the same settings ( ISO 200, 3.2m distance,single spot meter on 6m, on tripod, shutter 1/1250, F2.8)... Same results on both cameras 70mm is the worst 200 mm seems to be the best. I see the focus over on the left of the shot... I was aimed EXACTLY dead on at the white spot below the 17.. and this is with OS off. I've posted the shots from 70mm thur 200 on my workshop and here is the first shot and the last shot.... Opinions???
70 mm

200mm

Thanks Guys!

OH and the marks on the yardstick are just as black all the way thru to the naked eye

Message edited by author 2012-06-24 15:13:12.

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/24/2012 03:15:26 PM · #19

Oh and I don't OWN a D700 wish I did, I used a freinds for a challenge shot, and so I listed it in my profile...

Bear_Music

Samsung Galaxy S21, S21+, S21 Ultra

Sony 24-70mm F4 Vario-Tessar T* FE OSS

06/24/2012 04:03:01 PM · #20

You need to be setting the yardstick up at and angle (like a stairway) and focusing on the 18" mark; seeing what actually IS in focus tells us if you have front or back focus.

The darkness of the marks means nothing, that's a matter of light reflecting off the black at a different angle.

The pictures you just showed us don't LOOK that bad, but we'd need to see them full size.

Message edited by author 2012-06-24 16:03:16.

06/24/2012 04:19:36 PM · #21

It's hard to tell from an 800px 72dpi and a bit O/E but they look sharp to me, however I would have run the yardstick away from you, not flat on.

I read this article quite some time ago however it is still relevant. //www.focustestchart.com/chart.html

Here is a shot taken with my 70-200mm f/2.8 on a D90 recently and it's sharp. This is what I expect of a lens of this calibre.

alexlky

06/24/2012 04:24:50 PM · #22

Edited: As per Harvey link

Message edited by author 2012-06-24 16:29:46.

Nikon AF-S Zoom-Nikkor 24-120mm f/3.5-5.6G IF-ED VR

06/24/2012 04:40:09 PM · #23

WOW I totaly missed that mark... Ok so going to read and do it again right.. Probaly still have a problem, this AIN'T my day, just found out our whole center beam that runs down the middle of the ENTIRE house is broke at one end and EAT up with termites.... $$$$$ Ka-Ching... Off to down a beer chill out and refigure the lens thing... (ps I'd never heard of front focus rear focus)

Yeah Harvey your shot is what I expect outta this lense, I've been useing a friends 1st gen of this lens w/o OS I've had some amazeing shots with that lense.

Ok back to study....

Message edited by author 2012-06-24 16:43:35.