naturepics43 Loc: Hocking Co. Ohio - USA

I know there are a lot of UHH members that use the Sigma 150-500. I need posts from all of you about your use of this lens. All the posts I've read on UHH have been very possitive about this lens. I'm on my SECOND copy of this lens and I'm still not happy! I NEED HELP! It seems that the DOF is much narrower than the DOF charts indicate. Is anyone else having DOF problems? I have a Nikon D90 & a D7000. Photos on the D90 are out of focus at all focal lengths ( I'm resigned to the fact that I can't use this lens on my D90) Now on the D7000 I have adjusted the AF fine tune with test charts @ 28 feet. When I went to the lake & shot photos of great blue heron the lens was focusing in front of target. So I set up a test rig & took controlled shots @ 150 feet but the DOF is less than 3 feet ( should be over 8 feet according to DOF charts) Has anyone else noticed this problem or do I maybe have another bad lens? Please respond as all postswill be helpful in solving my problem. Thanks in advance for your replies.

MT Shooter Loc: Montana

Your depth of field has little to do with your focal length and everything to do with your aperture setting. I used my Sigma 150-500m lens on my D90 before I sold it, both my D7000's and now on my D800E with excellent results on all of them. I even stuck it on my F5 for a couple of film shots and it was great on there also. The lens does have a learning curve due to its range, took me a couple days shooting to get comfortable with it when it first arrived, but its truly a great lens for the money.
Also, I have noticed most DOF charts are accurate with prime lenses and not so accurate with zooms.

MtnMan Loc: ID

Are you using spot focus?

If not the relatively small DOF at the long distances a 500mm lens is for will lead to most pics being out of focus.

And depending on your camera and subject a small movement in the spot can put your focus way off.

Also you may be seeing camera movement.

I love my Simga 150-500. But like MT Shooter found it had a bit of a learning curve.

I recommend trying higher ISO so you can get no slower than 1/1000 s and careful spot focus before you blame the lens.

glojo Loc: South Devon, England

Would it be beneficial if all parties were to post their images at 500mm along with the exif data so that everyone can see what is good, bad or indifferent?

shadow1284 Loc: Mid-West Michigan

Since so many of us, my self included are having such good results with the Sigma 150-500, maybe you should post some of your shots and let us try to evaluate your problem. I suggest your EXIF as well.

naturepics43 Loc: Hocking Co. Ohio - USA

Notice the shallow DOF! What DOF should I expect at 100 feet using f8? Maybe I'm expecting too much too soon. All three shots were taken on Manfrotto/Bogen tripod with remote shutter release. Any advise will be helpful. Thanks

D90 @ about 100 feet


D7000 @ about 100 feet


D7000 @ about 200 feet

MT Shooter Loc: Montana

On your first picture with the D90 you used F8 at 500mm and estimate 100 feet distance to subject, that would yield you a net DOF of 3.84 feet. The results are the same for the second shot with the D7000 at 100 feet, 3.84 feet DOF at 100 feet distance. I do not know why you slowed your shutter speed from 1/2000sec on the D90 to 1/4000sec on the D7000, but the second shot is definitely underexposed. Your focus distance shows as 21.13 meters on the D90 and 25.12 meters on the D7000. That is the front of your DOF as measured by the camera, not necessarily the distance to subject so the swan was just a bit closer than you estimated.
The Heron picture estimated at 200 feet (focus distance says 59.57 meters so you are very close there) shows you should have a DOF of approx 15.5 feet. If the heron is a typical example of about 4 feet tall, the water in focus in front of and behind the bird appears to be around 4 times its height, so 16 feet would be right on with the DOF estimate here also.
I took these calculations from DOFMaster software available free on the internet as I have found it to be pretty accurate compared to some of the other free programs.
The Swan is a high contrast subject and spot focusing on the head would probably be the best way to shoot it. The heron at that distance with the complicated background is a tougher subject and I would probably bracket that shot if I were taking it, or try to find a situation with a more distant background or closer subject to allow for more separation.
I have found my Sigma to be soft under F8 at above 400mm and almost always shoot it at F10 to F16 in these situations. The swan I would have shot at ISO 100 and probably F16 at that distance, again, spot focusing on the head as that is the critical area of the shot. The back feathers look very nice on the D90 shot, but the underexposure on the D7000 shot takes away much of this definition.
I hope at least some of this helps. Good luck.

naturepics43 Loc: Hocking Co. Ohio - USA

MTShooter---Thanks

ALL of your info will be helpful. I'm still trying to master the D7000 also as it was purchased at the same time as the Sigma lens ( Maybe too many new things at once ) The D7000 seems to be very erratic with exposure. I think it might be from too much light getting in the viewfinder between shots. You made my day! Thanks for the thorough explaination. I really, really like this lens. Now to make it work for me
PS where did you find the distance info?

Tony232 Loc: Warwickshire UK

I just find the VR very noisy otherwise OK comments welcome.

naturepics43 Loc: Hocking Co. Ohio - USA

Thanks for your words of encouragement. I'm finding that the 500mm is much more sensitive than my 300mm. As many have said: Practice, practice, & more practice! With all the great help I'm getting from UHH members I WILL succeed! thanks again.

naturepics43 Loc: Hocking Co. Ohio - USA

Sounds like a great plan. Maybe a new thread should be started

naturepics43 Loc: Hocking Co. Ohio - USA

Posted some just below your post complete with EXIF. All help is welcome, Thanks.

naturepics43 Loc: Hocking Co. Ohio - USA

I haven't used the VR very much.( It's one heavy lens!) I'll have to give it a try. Thanks

thefunxtr Loc: Atlanta

You say you have not used the VR (on the Sigma it's OS) very much ... If you are shooting "handheld" this is the star feature of this lens and you definitely should use it.

thefunxtr Loc: Atlanta

Another thought ... are you using any type of "filter" as a "lens protecter"? When I first got my lens I really thought there was something wrong with it until I finally tried it without the filter (which I had put on right after opening the box). I noticed a huge difference in the focus once I removed the filter. At that point I ordered a 2nd filter (same type) thinking it may have been defective but saw the same results. It was not an "expensive" filter, so I am considering whether I want to spend money for a real "quality" filter for protection or not, but this might be something to concider if you are using a filter for "protection".