Tamron SP 15-30mm f/2.8 Di VC USD Review
The Tamron SP 15-30mm f/2.8 Di VC USD is the first fast ultrawide zoom lens for full frame cameras to offer built-in image stabilization. It’s slightly wider than the closest offerings from Canon (16-35/2.8) and Nikon (17-35/2.8) but not quite as long when zoomed out. However, if you want a WIDE angle zoom, then you’ll probably appreciate the wider angle of coverage and not worry so much about the other end of the range. There’s also a Nikon 14-24/2.8 which reverses the situation, being slightly wider but not as long as the Tamron lens.
The Tamron 15-30/2.8 is an impressive lens in terms of both size and weight. It appears to be very solidly built and is nicely finished in textured black. It has a distance scale, a zoom ring, and a focusing ring that is active at all times so you have manual override of AF if you want it. There are two switches, one for AF/MF and one that turns stabilization on and off.
The fixed hood is an interesting design. It’s really two hoods, one inside the other, and the depth of the hood varies as the focal length is changed. This gives better shading of the lens at longer focal length settings without causing any vignetting at the shorter settings. The disadvantages of the fixed outer hood are that it makes the lens larger for storage, and the lens cap is rather large. The Tamron 15-30/2.8 cannot accept filters, either front or rear (more on that below), partly due to the fixed hood but mostly due to the protruding front element.
Tamron SP 15-30mm f/2.8 Di VC USD Specifications
Groups/Elements 13/18 Angle of View 110°32’ – 71°35’ (for full frame format)
85°52’ – 49°54’ (for APS-C format)
Diaphragm Blade Number 9 (circular diaphragm) Minimum Aperture f/22 Minimum Focus Distance 11 in. (0.28m) Macro Magnification Ratio 1:5 Filter Diameter N/A Weight 1100 g (38.8 oz.) Length 5.7 in. (145mm) for Canon
5.6 in. (142.5mm) for Nikon
Standard Accessories Lens caps (push-on front, rear) Hood Integrated flower-shaped hood Mount Canon, Nikon, Sony A (no VC)
Size and Weight
The Tamron 15-30/2.8 is a hefty lens. I was quite surprised by the size and weight when I took it out of the box. It weights well over 2 lbs. (38.8 oz. to be exact) and it’s 5.7" long and 3.9" in diameter (including the built-in hood). That’s quite a bit more than, for example, the Canon EF 16-35/2.8L II USM (1.4 lbs. and 3.5″×4.2″).
Left: Canon 16-35/2.8L II USM. Right: Tamron 15-30/2.8 Di VC USD.
The Canon does increase in size when the hood is added, but it’s still smaller and easier to carry even with the hood in place, and significantly smaller without it.
For now, forget filters. The Tamron 15-30/2.8 can’t accept front (or rear) mounted filters. The lens hood can’t be removed and the front of the lens has no filter threads. The front element extends out so far that it would hit any conventionally mounted filter. Even if the hood was threaded (which it isn’t), you’d need a 95mm diameter filter and it would likely vignette at the 15mm setting. At the 30mm setting you can hold a 77mm filter just in front of the lens by hand and not get vignetting, but there’s no easy way to mount it there mechanically.
Note the double hood, one sliding within the other.
It’s possible that, in time, someone might come up with a filter holder for 4″×4″ square filters, but a 4×4 circular polarizer is going to cost you at least $200, plus you’ll need to buy some sort of adapter/holder for it.
The filters you might use with this lens would be polarizers, neutral density filters (for long exposures), and split density neutral filters. However, polarizers on ultrawide lenses have limited use in any image with a lot of blue sky in it because the sky isn’t evenly polarized. Such wide lenses with a polarizer will therefore show uneven sky brightness.
Some photographers question whether IS (or VC—vibration control) is really useful with wideangle lenses since you can usually handhold them at pretty slow speeds anyway. While we know 400mm telephoto lenses can be stabilized down to speeds of 1/50s or slower, the question is whether stabilization still works when shutter speeds are in the 1/4-1 second range.
Well, judged by this lens, yes, they do. At 15mm without stabilization turned on, I needed at least 1/15s to get sharp images. At 1/8s approximately 60% of my images were sharp, and at 1/4s only 20% were. With stabilization turned on I was typically getting 100% sharp images down to 1/4s. At 1/2 second about 60% were sharp, and at 1s 20% were. I’d say that’s at least 2 stops of stabilization.
At 30mm results were a little better. At 1/2s I wasn’t getting any sharp images without stabilization, but with stabilization on I was getting 50-60% sharp images. That’s closer to 3 stops of stabilization.
While results may differ from person to person, depending on how steady their hands are, there’s still no doubt that stabilization works even with wideangle lenses and shutter speeds in the 1/4-1s range, certainly making it well worth having. It could easily be the difference between a sharp shot and a blurred one when shutter speeds are in the range of 1s to 1/8s.
The Tamron 15-30/2.8 is a very sharp lens in the center of the frame, even wide open. While sharpness does drop off slightly as you move away from the center, it’s still good out to the edges of the frame. The sharpness across the zoom range is also very consistent. Stopping down to f/4 gives a slight improvement, but stopping down another stop to f/5.6 doesn’t really show any additional gain. At smaller apertures, diffraction starts to soften the image as it does with all lenses.
At the edges of the frame, sharpness is lower as can be seen in the series of images below.
The image at 70% of the distance to the edge appears to be higher magnification, but it’s the same lens at the same focal length setting. The difference in size is due to the way very wide lenses “stretch” images near the edges. All rectilinear wide angle lenses do this and they all do it to the same extent. It’s a function of rectilinear lens mapping.
At 30mm the image sequence below shows much the same behavior.
I had a brief chance to compare real world shots taken with both a Tamron 15-30/2.8 and a Canon 16-35/2.8L using an EOS 5DS (50MP) DSLR. Wide open at 16mm, the Tamron lens was slightly sharper at the edges and showed less chromatic aberration. The same thing was seen at 28mm, with the Tamron again being slightly sharper and showing lower chromatic aberration. Both lenses were very good, but of the two samples I tested, the Tamron was slightly better overall.
The Tamron 15-30/2.8 controls chromatic aberration well. It is visible at all focal lengths at the edges of the frame and it’s slightly stronger in the middle of the focal length range (around 22mm) than at 15mm or 30mm. The CA should be easily correctable with suitable post exposure processing. The edge images above show the extent of the CA. Longitudinal CA was minimal.
Distortion is visible as barrel distortion at 15mm and pincushion distortion at 30mm. I’d estimate distortion at normal focus distances at 15mm as being around -1.5% (barrel) and around +1.5% (pincushion) at 30mm (full frame). In the middle of the range at around 22mm, distortion is negligible.
An example of distortion at 30mm.
An example of distortion at 15mm.
For a fast wideangle zoom, the Tamron 15-30/2.8 shows fairly low levels of vignetting. It’s strongest wide open and it covers a greater area of the frame at 30mm than at 15mm as the following image sequence shows.
I’d estimate the vignetting wide open to be around 1.5 stops in the extreme corners of the frame. The vignetting is more localized to the corners at 15mm than at 30mm. Wide open, it’s visible in images with large areas of uniform illumination extending to the corners (e.g., sky). One stop down at f/4, vignetting in real world images is just visible in the extreme corners. By f/5.6 the residual vignetting is unlikely to be noticeable in real world images.
The two shots of beach roses below showing bokeh at 15mm and 30mm were both taken wide open. As you can see, vignetting isn’t a big deal. It’s most visible in the area of blue sky at the top left of the image shot at 15mm. Vignetting is also fairly easy to correct in post exposure processing if you ever find it to be an issue.
Some photographers are concerned over the quality of the out of focus areas in an image (bokeh), but this is really much more of a concern for longer focal length lenses. With a 15mm lens (or even a 30mm lens) at f/2.8 you just can’t blur out backgrounds much, so the quality of that blur isn’t normally of primary concern.
This image shows maximum background blur. It was taken at the 30mm setting, wide open (f/2.8), and at the closest focusing distance of the lens.
This is a very similar shot but at 15mm.
As you can see, even when focused as closely as possible and shot wide open, the background blur at 15mm isn’t very strong.
Cadillac Montain, Maine, EOS 6D, Tamron 15-30/2.8 Di VC USD at 15mm, f/8. 1/50s @ISO 100.
The Tamron 15-30/2.8 does have a couple of areas that might be of concern to some. First, due to the design of the lens there’s no way you can mount a conventional circular filter on the front of the lens (nor can you mount rear filters). Secondly, the Tamron 15-30/2.8 is a large and heavy lens. It’s 13 oz. heavier than the
Milky Way, EOS 6D, Tamron 15-30/2.8 Di VC USD at 15mm, f/2.8, 20s @ISO 4000.
If I was currently looking for a fast wideangle zoom, the Tamron 15-30/2.8 Di VC USD would be a very strong contender. It’s sharp, it has effective stabilization, and it’s $200-$300 less expensive than similar lenses from Canon or Nikon. On those grounds it is a clear winner. The one attribute of the Tamron lens that would concern me most would be the lack of the ability to mount filters. However, the
Aurora Borealis, Tamron 15-30/2.8, 15mm, f/2.8, 8s @ISO 3200.