Update—23 May 2017: There are better long telephoto zoom lenses available now than this Tamron 150-600. The choices include the newer 2nd generation Tamron 150-600mm f5- 6.3 G2, the Sigma 150-600mm f5-6.3 Contemporary, the Sigma 150-600mm f5-6.3 Sport, and the Nikon 200-500 f5.6. I personally would recommend any of the 150-600 zooms over the Nikon 200-500 simply because of the extra 100mm of zoom length. If there is one thing I have learned in the past 20 years of bird photography, it is that there is no substitute for reach; an extra 100mm of focal length is a big advantage.
Photographer Brad Hill extensively evaluated many of these long telephoto zooms in a series of blog posts between March and December 2015. Here is a link to his blog. You’ll have to scroll back through the blog to find the posts on these lenses. The best performer in his opinion was the Sigma 150-600mm Sport. Based partly on his review, I sold my Tamron last year and bought the Sigma 150-600mm Sport. It is extremely well built, quite sharp, and overall I have been very pleased with the lens. However I must admit that if I had read this review prior to my purchase, I may have opted for the lighter, less expensive Sigma 150-600mm Contemporary.
Although I received my Nikon mount Tamron 150-600 several weeks ago, I didn’t get to really test it out well until this past weekend. I decided to do field and resolution chart tests comparing the Tamron to my Sigma 300-800 f5.6 lens and Nikon 200-400 f4.0, ver 1 lens (with and without the TC14EII teleconverter). The camera used was a Nikon D800. All lenses had had their AF calibrated using Michael Tapes’ LensAlign. The field test consisted of photographing a Great Crested Flycatcher nest while the chart test utilized the 1951 USAF resolution chart pattern. I post full frame and 100% crop images of the field test as well as 200% crops of the resolution chart images; so you’ll be able to judge lens quality for yourself. Bottom line: I was very impressed with Tamron 150-600mm lens. And surprisingly, I found myself retesting the 200-400 with the 1.4X teleconverter to try to determine why it was the poorest performer.
Comments on lens testing in general:
Many photographers don’t really test their lenses other than just shooting with them in the field. I find it hard to accurately judge lens quality in this manner: shooting a variety of subjects in differing light conditions with the subjects at differing sizes within the frame. I test my lenses using a resolution chart test and a practical field test.
The chart test is an evaluation of the optical quality of the glass in a controlled situation. If the lens isn’t sharp in the controlled test situation, then there is no way to get good images in the field. However, a good chart test doesn’t always mean that it will perform well in the field. So the controlled tests need to be followed by an evaluation of how the lens performs in practical usage. This is a much more subjective evaluation.
The ideal field test compares your new lens to a known quality lens by shooting the same subject in the same light conditions at the same subject magnification. This initial field test (with the subjects the same size in the frame with the different lenses) also helps you decide the significance of small differences in the resolution chart test. Is a difference of two levels of resolution in the flat high-contrast 1951 USAF chart really noticeable in your images of multi-toned three-dimensional subjects? Or do other factors, such as quality and quantity of light, play a bigger role in the apparent sharpness of your images?
If the resolution chart test is excellent but the field test is poor, then you need to check lens autofocus accuracy, tripod stability, as well as your own photographic technique (especially important when shooting with long telephoto lenses).
I tested the Tamron lens at 600mm because all the reviews and tests I’d seen concluded that that focal length gave the poorest performance. Some reviewers said it was soft at that focal length while others said the lens still performed well at 600mm. However, very few of these reviews gave adequate sample images that allowed me to judge for myself. For bird and wildlife photography, we tend to use the longer focal lengths a lot. I needed to know if I could rely on the Tamron at 600mm.
I decided to position my blind at the flycatcher nest so that a 600mm focal length was needed to get the desired subject size in the frame. At that position, with the equipment I own, I had three lens choices: the Tamron 150-600, the Sigma 300-800 (set at 600mm) and the Nikon 200-400 with TC14EII (providing a focal length of 560mm). The flycatchers were returning to nest about every 15 minutes and I shot the subject several times with each lens wide open and stopped down one stop. Image stabilization (VR, VC) was not used.
I selected the sharpest sample images and adjusted only exposure and contrast in Adobe Camera Raw. I processed the images in Photoshop using Topaz Denoise, followed by sharpening with Nik Sharpener Pro. My noise reduction method is to view the image at 200% in Topaz Denoise, select the noise reduction preset that gives the best result and then fine tune with the Strength and Shadow sliders. I look at an area of finest detail in the image and apply as much noise reduction as I can without losing this separation of detail. I then apply a standard amount of sharpening with Nik Sharpener Pro.
Below are full frame images and 100% crops.
Figures 1A & B: Tamron 150-600 at f6.3
Figures 2A & B: Tamron 150-600 at f8.0
Figures 3A & B Sigma 300-800 at f5.6
Figures 4A & B: Sigma 300-800 at F8.0
Figures 5A & B: Nikon 200-400 with TC14EII at F5.6
Figures 6A & B: Nikon 200-400 with TC14EII at F8.0
I think an image of a bird fairly large in the frame is a great subject for evaluating sharpness. There are levels upon levels of texture and fine detail within the subject.
My initial subjective interpretation from these images was that the Sigma 300-800 gave the sharpest results, both wide open and stopped down one stop. The Tamron was very close to the Sigma, especially stopped down 2/3’s of a stop. Surprisingly the 2oo-400 with the 1.4X was the poorest performer (more on that in a moment). However there are other factors to be considered. Even in as controlled a field test as this, there were changes in the conditions that possibly affected my subjective evaluation.
First, the lighting changed during the shoot. The Tamron images were taken in full sun and fairly harsh light (look at the contrast on the flycatcher’s beak in figures 1B & 2B). The Sigma shots were taken in softer light (look at smooth tonal values in the 100% crop) and are just naturally more pleasing to the eye than the more contrasty Tamron shots. That can affect subjective interpretation.
Most of the Nikon images were taken under cloud cover. I had to increase the ISO by a stop to maintain shutter speed. The flatter image and higher noise levels certainly can affect sharpness interpretation. However the 200-400 was significantly less sharp wide open than either the Sigma or the Tamron. Studying the images a little more closely, I noticed the Nikon lens was front-focusing (compare the feather detail in the head vs shoulder areas of Fig 6B). It had been quite a while since I had checked the AF calibration of the Nikon lens with teleconverter, so I redid the calibration and had to adjust the AF fine tune setting by seven steps.
At the conclusion of the field test, I must say I was very impressed with the Tamron lens. The lens autofocused quickly and the sharpness was impressive. I would not hesitate to use it wide open, if necessary, at 600mm. However, whenever possible, I’ll stop down a little.
Please read Part 2 of this article (hopefully published within a week) to see if the controlled test confirms my interpretations from the field test, and to see how the 200-400 lens alone compares to the lens paired with the TC14EII. I’ll also sum up my overall opinion of the Tamron 150-600 lens.