Introduction

What follows is a multi-part users' review of the Sigma APO 120-400mm F4.5-5.6 DG OS HSM. I will update the review on each day that I use the lens. The lens in question is rented from LensRentals.com.

Specifications:

Since I shoot with Canon cameras, I obviously rented a lens with a Canon mount. I will be testing the lens with both an EOS 40D and a Digital Rebel XTi.

My first impression of the lens is that it is big. Really, really big. But, not larger or heavier than a Canon EF 70-200mm f/2.8L IS with a 2X-II converter. In fact, it may be slightly smaller than that combination.

Build quality appears to be excellent, and Sigma have applied an interesting matte-black finish on the lens barrels. The zoom and focus rings operate smoothly, although they are somewhat stiff. The OS (Optical Stabilization) mode switch and auto/manual focus switch, while not as nice as the Canon lenses, seem to be quite adequate.

The OS system is similar in concept to Canon's system, and shares the same two-mode operation. In Mode 1, both horizontal and vertical shake is reduced, and in Mode 2, only vertical shake is affected. Sigma claim up to 4 “stops” of vibration reduction, meaning that if you can hand hold a 400mm lens at 1/500 without OS, then you should be able to handle this lens at 1/60. My guess is that, unless the OS is significantly better than Canon's, I will only be able to get down to about 1/125 at 400mm without seeing the affects of my shaky hands.

Sigma have incorporated an HSM focus motor on this model, which is designed to allow switching from auto to manual focus by simply grabbing the focus ring at any time. It's an internal-focus lens, so the front element does not rotate with focus. Also, there is a marked focus scale on the lens. “Racking” focus from closest focus to infinity is approximately 1/3 turn.

Turning our attention to the zoom … Unlocking the zoom and moving from 120mm to 400mm causes the lens to grow another 2-3 inches in length. While I would prefer an internal zoom, this would not be a show stopper for me. There is a lot of glass in this lens, and, unless the zoom is locked at the 120mm position, the zoom will creep when the lens is pointed down. However, the lens has to be tilted almost all the way down before creeping begins.

The lens comes with a round-type hard plastic lens hood and also with a hefty tripod mounting collar/handle. Some people have complained that the tripod mount gets in the way of hand-held operation, and I can see where this might be a problem, although I think that positioning the collar appropriately will alleviate most issues.

If you're one to use filters, 77mm filters will be required for this lens. Unlike some other newer lenses, the supplied lens hood does not provide a “rotate assist” for polarizing filters — you'll need long fingers to reach the filter ring if you use the hood and any kind of rotating filter at the same time.

There are alignment marks on the lens and tripod mounting collar at the zero and ninety degree points, as well as an indication as to the position for removal of the collar. However, rotation of the collar is not very smooth, and so it is difficult to achieve an accurate alignment. This is in contrast to the Canon mount on my 70-200mm f/2.8L IS, which is silky-smooth. This may be easier to deal with when actually mounted on a tripod.

So, that would be part 1 of this review. I'll follow up with additional reports as soon as I can.

In Daily Use

Okay, MTF charts and a couple shots off the front porch are one thing. What's the Sigma APO 120-400mm F4.5-5.6 DG OS HSM like to use in the real world? It's big, it's heavy and it's sharp.

Fellow CMPG Member Earl Blake, Donna and I spent pretty much all of Saturday on the club outing to Chestertown for the Sultana downrigging. I thought this would be an ideal opportunity to put the lens through its paces. The day was bright, warm and a little bit hazy, which would certainly make for challenging images of the tall ships when they were more than a two or three hundred feed away. Frankly, I was amazed at how well the images held up (with just a little help in Lightroom).

As you can see from the photo above, the sharpness and detail is quite good. This was shot hand held at 400mm. I'm probably 250-300 feet from this fellow, once you account for my distance from the boat, and how high he's perched in the rigging!

At one point in the day, I handed Earl the camera to let him play with it, and he shot a great sequence of a small seaplane that flew over.

The first of these images is simply cropped to 8×10, with no magnification. The sharpness and detail was immediately impressive when we looked at the picture on the back of the camera. What was really stunning was “zooming in.” If you look closely in the second image, which is blown up to 100%, you can see what we saw — the pilot, and that he's wearing his seatbelt and sunglasses!

Of course, we weren't there to see airplanes. We were there to see tall ships. A selection of images from the day taken with the Sigma lens are below.

As mentioned previously, this is a heavy lens. I carried in on-camera most of the day, and had to hold the camera in my hand at all times, because I had managed to leave my camera strap at home. By the end of the day, my right hand and arm were very tired. That's not surprising, since the combination of a Canon EOS 40D body, BG-E2 battery grip with two batteries and the lens totals up to six pounds, six ounces. I was also wearing my Lowepro AW300 sling pack all day, which really begins to bother my right shoulder after a while. So, by the end of the day, I was very tired and sore, but still able to squeeze off decent hand-held shots.

If you're looking closely, you can almost read the word “warning” on the yellow sticker on the dome of the tightly cropped version of this image!

Wow! Sure, that last one's a little noisy, but consider the magnification.

This morning, I headed out early to try to chase my photographic nemesis — the Great Blue Heron at Wilde Lake. In addition to the usual array of lenses, etc., I also brought along the tripod with an Indian-made clone of the Wimberly gimbal head, which I'll talk about separately. However, when I arrived at the lake, the light was horrible, and the only birds in sight were a couple of ducks. Soon enough, a couple of geese made an appearance, paddling across the lake.

Before too long, the air was full of honking and squawking, and several of their buddies arrived.

I read on several lists that this lens was not much good at catching birds in flight. This weekend, I think I've figured out that, while sometimes challenging, it's not a bad lens for it.

It's also pretty good for quickly finding and capturing little birds, like this White Breasted Nuthatch which was scurring up and down the branches of the trees ringing the lake in search of bugs to eat.

I did finally catch up with the Heron, although not where I expected to find him. Today, he was fishing in the shade towards the east end of the lake, and down at the bottom of the dam.

This next, uncropped shot is from 500-600 feet, of a fellow watching the geese do their cleaning and preening routine:

Looks to me like he's talking to the geese about something!

And, I was able to do a good job of capturing the action. I'm probably 400 feet or so from the goose who is "displaying."

The two shots were taking with the camera on high-speed burst, and the second is cropped (obviously).

So, the first two days of actual shooting with the lens, both off tripod and on, were quite successful. The focusing accuracy is far better than the 70-200 + 2x converter I had been struggling with, and the "package" is a bit easier to handle.

I'll be continuing to shoot with this lens through the week, and maybe into next weekend, and will continue to report my results.