can you check out my sigma 50-150 f/2.8 test?

[jonsjons]

<p>hey guys, so i just picked up the sigma 50-150 via craigs list with the understanding that the seller would let me put it through its paces and return it if all is not well. i ran two series of tests, one indoor and one out, to gauge its performance at every aperture. it seems to do pretty well to me, but i've not run these sorts of tests much, so i thought i would ask your opinion.<br />for the sake of keeping things simple, i'm posting shots (100% crops) comparing center performance at f/2.8 and f/8 at 50mm, 100mm, and 150mm; basically the worst and best shots in terms of sharpness at each length. there is a noticeable difference which increases with focal length, the 50mm shots looking to me almost indistinguishable. the differences in my outdoor test - more of a 'real-world' setup using a fence- are harder to notice.<br />so my question is what you think of the level of softness i'm getting wide open, particularly at the longer focal lengths of 100 and 150mm. this softness pretty much disappears at f/4 (100mm) or f/5.6 (150mm). a little softness wide open at longer lengths is to be expected, right?<br />all shots were taken on a tripod using a remote release. the top half of each image is at f/2.8, the bottom at f/8.<br />whaddya think?</p><div></div>

[jonsjons]

<p>#2</p><div></div>

[jonsjons]

<p> </p>

[jonsjons]

<p>#3</p><div></div>

[jonsjons]

<p>sorry about the sizing issues</p>

[dan_brown4]

<p>I owned that lens for some time. Yours looks pretty good in the center. For that lens, the gremlins live in the corners at the 150mm end.</p>

[elliot1]

<p>I think you should consider going out and taking some 'real' pictures (representative of what you would be shooting with it) and then make a decision!</p>

[steven_moseley1]

<p>Agree with Elliot...most of this pixel peeping is pointless waste of time....how do you know 100% that yours is a good copy....YOU DONT....no matter how much peeping you do :)...take some REAL photos, properly 'processed' and see if it is good enough for what you do or not.....but dont blame the seller if your views are considered too subjective.</p>

[eric_arnold]

<p>shoot some portraits with it at 2.8 or f/4 and marvel at the bokeh. but yeah, 2.8 should seem a bit soft, especially on a test chart, improving at f/4, and max. sharpness at 5.6. in real-world conditions, 2.8 is perfectly usable provided you have some distance between foreground and background and some contrast in the shot.</p>

[steven_ej]

<p>I don't think your test subject is a good one at all.</p>

[cowboystuff]

<p>Yes, you need to do some real tests on real subjects, to see all it can do.<br>

I own one and I think it's a great lens.</p>

[jonsjons]

<p>don't know if anyone's still listening, but yeah - i didn't buy the lens to shoot the newspaper with it. it was just a convenient way to eliminate as many variables as possible and quickly evaluate the lens' performance. anyway, here are some preliminary 'real' snaps. my subject (her name is Terra) was running around quite a bit, and i found the autofocus to be nice and fast. overall, i am quite pleased with the lens.</p><div></div>

[jonsjons]

<p>second one</p><div></div>

[cowboystuff]

<p>Those are much better photos!</p>