Image Quality

After returning from the grizzly bear trip, I spent some time studying the images from the Tamron in great detail. What was immediately obvious to me was that I liked them a lot more than our lab tests would have suggested I might. The lab test results were good, especially for the cost of the lens and focal length, but there were some concerns about sharpness at the 600mm end, as well as chromatic aberration that appeared across much of the image at both extremities of the range.

On close inspection, the expected red-cyan fringing was often not visible, and many of the images in this review required no chromatic aberration correction in Adobe Lightroom at all. I've certainly seen far worse performance from many, far more expensive wide-angle lenses. What is different about the fringing that I did see, is that when it does show up, it can be seen at any part of the image, where usually we would see it confined more to the edges of the frame. The aberrations are lateral enough that they can be removed easily with one click in Lightroom or similar software, though.

Close inspection showed a mostly cyan fringe at 600mm and an aperture of F6.3 or F7.1, but things improved quickly at F8 and beyond. As test results suggested, the cleanest focal lengths for aberrations were in the middle of the zoom range, but never were they either a problem to remove, or something that would have given me cause to change the way I was shooting.

Grizzly bear in the Chilcotin Mountains, British Columbia.  Tamron 150-600mm @500mm + Canon 5D Mark III - f/6.3 , 1/250, ISO 4000 - Raw file processed in Lightroom CC. Exposure +0.05, shadows +18, whites +13, blacks -1, saturation +5.

Perhaps more interestingly, the story was similar with the overall sharpness of the images as well. I was genuinely surprised at the results I was seeing on my screen and had to repeatedly re-confirm what focal lengths were used for certain shots. The difference in sharpness between the 150mm end and the 600mm end, was not nearly as much as I was anticipating. That's a good thing, because in the heat of the moment, it's very difficult to limit your zoom positioning to specific parts of the range. I was worried that I was going to feel like I had to limit myself to using only the 150-500mm area, but having studied the photos closely, I did not feel that was necessary.

Since you never really want to get too close to a grizzly bear, the vast majority of my best photos with this lens from the first trip, were shot at 600mm. Stopping the lens down to F8 makes a noticeable difference in fine detail reproduction but neither of the bird images in this review were shot with an aperture that small, and there is still adequate detail in the feathers at F7.1.  

Kildeer, Boundary Bay, British Columbia.  Tamron 150-600mm @552mm + Canon 7D Mark II - f/6.3 , 1/2000, ISO 800 - Raw file processed in Lightroom CC. Highlights -25, shadows +27, whites +38, vibrance +13.

When it comes to corner sharpness, I think this is a case where lab results can again give a worse impression than results in the field. I pay particular attention to corner sharpness with my wide-angle lenses since there are often important foreground elements in the image that stretch to the corners. When it comes to longer telephoto lenses for sports and wildlife, the subject matter rarely falls in the corners, and the often shallow depth of field masks any perceivable difference between corner and center sharpness. Perhaps I would have seen differences if I had designed test shots to look for them, but that wasn't the point of this test since it had already been covered in the lab. In real-world shooting, any difference was a non-issue for me, even when I deliberately went looking for it in the images afterwards.

APS-C 

My second trip with this lens was to Banff and Jasper national parks in the Canadian Rockies. The winter landscape there is filled with interesting wildlife and for this trip I shot almost exclusively with the lens on the 7D Mark II, due to the increased AF performance that I mentioned before. With the knowledge of my results from the first trip, I was much more confident in using this lens, even though I also had my monster Canon super-telephoto lens with me.

The small size of the lens makes it perfect for locations like the Canadian Rockies, or Yellowstone National Park, where wildlife can often be seen on the side of the road. On my trip to Jasper National Park, I quickly got into the habit of mounting the lens to my camera and keeping it next to me in the front of the car, ready at a moment's notice.

Driving along the highway, I came across a group of sheep grazing right on the side of the road. As I got closer, I saw the potential for a beautifully colored background, caused by one of Alberta's stunning green lakes. The opportunity was there for no more than a couple of seconds, and I wound down the window, reached for the lens from my passenger seat, and quickly got the shot.

Bighorn Sheep, Jasper National Park, Alberta.  Tamron 150-600mm @484mm + Canon 7D Mark II - f/7.1 , 1/200, ISO 125 - Raw file processed in Lightroom CC. Exposure +0.35, highlights -22, shadows +42, saturation +6, vibrance +8.

This seemingly innocuous encounter was a revelation because it dawned on me that this shot, possibly my favorite of those few days in Jasper, would not have been possible with my big Canon 200-400. It's unlikely I would have had the big Canon lens on the seat next to me in the first place, and even less likely that I could have wielded it so quickly and so steadily, hand-held out of the window to catch that fleeting moment. It really opened my eyes to the benefits of having a smaller, lighter wildlife lens in certain situations.

Studying the images from this second trip didn't deliver any surprises. Vignetting had appeared well controlled on my full frame camera, so the cropped sensor of the 7D Mark II delivered even better results in that regard. The fine-detail reproduction of the 7D Mark II is not as good as the 5D Mark III, which meant stopping down to F8 when using the full 600mm was more of a consideration. Of course on the APS-C camera, you have a 960mm equivalent reach so I also found myself needing to shoot a lot less at the 600mm end of the range anyway.

It was a fantastically fun combination to use for this kind of photography and It's hard to underline how useful that kind of range is, in a lens that weighs so little. I found myself singing its praises to every other photographer I met at those locations even though they were more distracted by the big white lens that was in the camera bag.

What should not be underestimated is the necessity for an even faster minimum shutter speed when using this lens on a camera with an APS-C sensor. The difference between 600mm and 960mm is considerable and if you are constantly using the lens at its furthest reach, it will eventually limit the length of time you can use the lens at dawn or dusk when you're struggling for enough shutter speed to keep it steady. Zooming out to 375mm will give you a 600mm equivalent, and this also widens your maximum aperture to F5.6 which will put you back in the game for a little longer.

Icefields Parkway, Jasper National Park, Alberta. Tamron 150-600mm @375mm + Canon 5D Mark III - f/10 , 1/400, ISO 100 - 2-shot Raw panorama merged in Lightroom CC. Processed to black and white with Nik Silver Effex Pro 2.

With the lens back on my 5D Mark III, I also found use for the lens at the 150mm end when taking some landscape images on the famed Icefield Parkway that runs between Lake Louise and Jasper. This produced some wonderfully detailed images of the mountains and glacial ice formations as you can see in the vertical, stitched panorama above.

To rent or to buy?

Until recently, there hadn't really been any great, affordable 600mm solutions, and for a lot of people this meant renting a lens for their once-in-a-lifetime wildlife trip. You can expect a 10-day rental of a Canon 600mm F4 to set you back more than $600, so the possibility of owning your own lens for only a few hundred dollars more than that, is surely something that's going to be on a lot of people's minds.

Almost all of the wildlife that I shot with this lens was static at the point of pressing the shutter button. That's often the case, unless you are predominantly shooting birds in flight, or fast-paced predators hunting in Africa. For static wildlife, the Tamron 150-600 clearly does an excellent job, and there's a lot to be said for owning a lens and getting used to shooting at these much longer focal lengths.

If I was headed to Africa though, where game drives are often at the very extremities of the day, I would still recommend renting a more expensive option that allows a larger maximum aperture and faster autofocus in low light. That's not to say there wouldn't be room on the seat next to you for the Tamron as well, but a wider aperture will keep you shooting for longer and if you've spent the money to get to a remote and truly exotic location, I think it's still going to be worthwhile. The combination of the huge zoom range of the Tamron, alongside a super telephoto with a larger aperture, would be an excellent pairing, just as I had on my trips to Alberta and British Columbia.

Incoming competition

In the last few weeks of testing the Tamron 150-600 F5-6.3, I fielded an incredible number of questions from people about my thoughts on this lens, compared to the Sigma 150-600mm F5-6.3 DG OS HSM Sports Lens and the Canon EF 100-400mm F4.5-5.6L IS II USM. That's an interesting question because those lenses have some significant differences. The Sport version of the Sigma lens is almost twice the price of the Tamron, and the Canon 100-400 is more expensive again, and falls considerably short of both of them in terms of reach. For most fairly serious wildlife photography, 400mm is not long enough, but on an APS-C camera like the EOS 7D Mark II, the 640mm equivalent would work very well.

If you're shooting with a full frame camera, you'll be pleased to have the added reach of either of the 150-600mm options, but bear in mind that one of my favorite features of the Tamron lens was the light weight and portability. Measuring 11.4 in./29cm in length and weighing in at 6.3 lbs/2.9kg, the Sigma is nearly 50% heavier than the Tamron, and almost an inch and a half longer. Considering the generally good performance of the Tamron lens, at a price tag of nearly half that of the Sigma lens, it's hard not to recommend it.