The longitudinal chromatic aberration is corrected by the Sigma very well so it won’t bother you at any focal length. The sample shots, taken at 600 mm and presented below, show that very clearly. Even at the maximum relative aperture it would be difficult to notice any traces of that aberration.  Please Support UsIf you enjoy our reviews and articles, and you want us to continue our work please, support our website by donating through PayPal. The funds are going to be used for paying our editorial team, renting servers, and equipping our testing studio; only that way we will be able to continue providing you interesting content for free. - - - - - - - - - - - - - - - - - advertisement - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - The correction of the lateral chromatic aberration also should be described in positive terms. The graphs below present the performance of the Sigma C 150-600 mm respectively on the APS-C sensor and on full frame. It’s worth reminding here that we call the chromatic aberration imperceptible up to 0.04% and up to 0.08% it’s level we consider as low. In the case of the Sigma the aberration is higher than 0.08% only at 600 mm and by apertures ranging from f/16 to f/29 so those not especially popular or commonly used. Such a performance can be called only brilliant. Still, the biggest rival of the Sigma, the Tamron 150-600 mm, had almost identical results in this category. In its case that aberration level exceeded 0.08% at the maximum focal length and only after a significant stopping down. Spherical aberration The Sigma C 150–600�mm f/5–6.3 DG�OS�HSM corrects the spherical aberration pretty well. There is no “focus shift” effect and the appearance of defocused light points is quite good – images we got in front of and behind the focus are very similar, you cannot find anything disturbing in them. There is a lot to like, not least its fast focusing (which you can set to even faster if you need it, or slower, more precise if you want that instead. With the dock (that came free-of-charge with mine) you can do a lot of fine-tuning, although for me I have not seen the need for that. I have made both the faster and slower AF available with the custom switch on the lens barrel, but if that suits everyone, I have no idea. I mainly use it with my CX cameras (a.k.a. Nikon 1 cameras), my DX camera (a D3300), and occasionally with my FX camera, then usually with TCs. In good light, it is a delight to use with the Nikon 1 V2 (my J5 has too small a battery to work with big lenses like this one), but with the D3300 it is such a superb experience to use it, both close, and at infinity! I have used it with the TC-1401, the dedicated Sigma teleconverter, but far better is using a cropped sensor (the D3300 has a crop factor of 1.5, the Nikon 1 cameras have one of 2.7! So my normal equivalent focal length is either 500-600 x 2.7, that is, 1,350-1,620 mm, or when used with my D3300 500-600 x 1.5, which is 750-900 mm. Add a TC, or two, and we're talking focal lengths up to 3.2 meters! Contrast goes down with TCs, so I try to avoid them. Any serious problems?! Well, its size and weight make it easier to use on a stable tripod, with a sturdy Wimberley Sidekick, or similar head, but there are those that use it handheld! When used on a tripod I find, if it is dead calm, it better to use it with the OS (Optical Stabilisation) off, but if it is better to have it on if the lens wobbles a lot due to wind, or similar causes. At 3.2 meters focal length I use a timer or remote to minimise shake. Back to the Nikon 200-500 contra the Sigma Sport: Without their lens-shades, the two lenses are roughly the same size and weight, but the lens shade on the Sigma weighs almost a pound (over 300 grams), and its center of gravity moves outward a lot as you zoom out. So weight is an issue unless you have a very sturdy tripod, and ditto head. The Nikon 200-500 is a slower focusing lens, and originally there were quality issues as well (numerous review sites had issues with the lenses that had been sent to them, while I have heard nothing similar about the Sport. The Nikon 200-500 is an internally focusing, constant length, lens (same length at 200 as at 500), thus should have no problems with big weight-shifts as you zoom in and out. That's a big plus! Addendum A year after I posted the review above, almost to a day, I find it just as good as I did then, but I have changed its use a bit since then. First, I've added an Arca-Swiss compatible rail to the lens-foot, so that it balances better, and I now rarely use a tripod. Instead, I use one of the heftiest monopods I've seen on the market, a Gitzo GM5541, with a cheap FotoPro head, which I plan to upgrade to something heftier. And I never turn the Optical Stabilisation off, which I did when I used the lens on tripods, at times. The limiter gets frequent use, especially if the lighting and/or contrast are dull. The biggest step forward was upgrading to a D7500, with its far better high ISO capacity, due to its lower-noise sensor, and the fact that it is equipped with a much better AF module than my old cameras. That proved to be a great blessing in combination with this lens, as in certain situations you'd want a faster lens, as always. So that's probably what differs most between this lens, and the Nikon 200-500, the latter is a faster lens at the long end. And the Nikon lens is internally focusing so less problem with Center of Gravity shifts as you zoom in and out. The Sigma focuses far faster, but there are always workarounds so in real life the difference between the Sigma and the Nikon is not that big. But I am delighted that I can refocus from infinity to a subject a couple of yards away in less than a second, and zoom at the same time, by pulling the front of the lens towards you (no need for turn the zoom ring by hand). |
