Focusproblem with Sigma 150-500

[thorkild]

<p>I have a focusing problem with my Sigma 150-500 mm when using it at 500 mm (with Nikon d200). At f:6,3 the sharpness of the photo is simply not good enough. I am now experimenting with single point focusing. Is it the way to go?</p>

[evannorth]

<p>the sigma 150-500 is well known to be soft at 500mm. try manually focusing on a good tripod with os switched off, single point af, using remote shutter release or timer on a distant still object and then check sharpness.<br>

lighting and atmospheric conditions can also affect image sharpness but it is a fact that this lens can often be soft over 350mm. </p>

[elliot1]

<p>Is your lens focusing properly, or mis-focusing? Are you ever getting accurate focus?</p>

 

<p>What aperture are you shooting at when taking pictures at 500mm? What shutter speeds are using at 500mm? Are you shooting hand-held or with a tripod/monopod?</p>

<p>Keep in mind that exceptionally good technique is required when shooting at 500mm. When shooting with a tripod that is not rock solid, even the wind can cause vibrations which can give the appearance of sharpness issues when shooting at 500mm.</p>

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[Wouter Willemse]

<p>Single point focussing using ONLY the center AF point, which is more sensitive than the others, might help. But several factors simply play against it, as the others have noted.<br>

Nikon rates the AF system used in the D200 to be reliably functional with lenses up to f/5.6. Meaning, slower lenses they will not guarantee that AF action is fast, reliable or accurate. The Sigma is slower at the long end.<br>

Plus, as Evan noted, it's known to be a bit soft at the long end. You need to stop down to at least something like f/8 for good sharpness. At which point, everything that Elliot mentions becomes tricky. </p>

[wedding-photography-denver]

<p>Not sure about the D200's AF system, but I find that the AF methodology will handle most things with Nikon's AF ability. However, having tried that lens (twice) and returned it both times, I would guess your lens may mis focus somewhat at that FL and without AF fine tune, it will be hard to get it back within acceptable sharpness IMO. F6.3 should not be tack sharp on that lens though, but by F8 you should be singing a happier song. If not, send it to Sigma or back to where you purchased it.</p>

[Andrew Garrard]

<p>Some people seem to be very happy with their 150-500. I'm not one of them, though I'm prepared to accept sample variation (early reviews seemed much more favourable than recent ones). At the 500mm end, mine is sharp-ish on a D700 at f/11, but diffraction limited by the time it does my D800 justice (and f/11 combined with 500mm needs a lot of light). The lens is okay at shorter focal lengths, but I believe there's no budget route to a decent 500mm. The cheapest options I'm aware of are the 500mm f/4 AI-P (which is okay at f/5.6 on a D800, but manual focus), the new 80-400mm Nikkor, and the 300mm f/4 AF-S + TC-14E - and the last two don't quite get you to 500mm (though there's the TC-17E if you want to risk the autofocus). The Sigma 150-500, Sigma 50-500 (Bigma), 200-500 Tamron and older 80-400 Nikkor are all a bit iffy at the long end. I've been meaning to get around to selling my 150-500 for over two years now...<br />

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Good luck, but you may be limited by the optics. I suggest stopping down and not looking too closely.</p>

[rainer_lucks]

<p>Well" I took the chance in purchasing the Sigma 150-500 mm. I always know the Sigma to be a little on the soft side being the reason I never bought one. But! It was the only Lens at a reasonable price that gave me a 500 mm range. I had to send the Lens back twice as it is suffering from annoying back focus. Even my fine tuning on my D7000 to -20 got it to an almost reasonable focus. of course this is not acceptable and no one should have to fine tune their Camera to more than 12-/+<br>

I am not interested in sending the darn thing back another time for them to fiddle about with. I think I got a Lemon and I like my Lens replaced or my hard earned Money returned back. Perhaps many of the 150-500mm lenses are some what Lemons? Seem to be a lot of not so clear images at the far end and I trust not all of them knowing how to handle a Camera?<br>

I certainly know my stuff and I know it is the lens. I was even confirmed by them as being back focusing. I would not purchase another Sigma again. I stick to my Nikon 55-300 mm. It out performs the 150-500 as far as reliable functionality is concerned.<br>

if you think your Sigma lens is not doing its focusing part then it is most likely that you are correct.</p>

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