I’ve recently aquired the Tamron 150-600 zoom. A lot has been written about this lens; I’m not going to repeat what’s already been written all over the web. Dustin Abbott wrote a really good hands on review that I completely agree with, and he’s graciously included 100% crops, RAW files etc for you pixel peeping people. DXOmark’s analysis is, as always, the gold standard in optics measurement. Lensrental did a side by side with the Sigma and Canon super teles, and their results show some real world confirmation of DXOmark’s findings. If you want to look at charts, graphs, 100% crops and hear about “build quality” and “feel”, those links will tell you everything you need to know.
I’m used to fast primes – For the last couple years, my slowest lenses have been f2.8. I’m also a bit of an IQ snob, therefore my ISO dial has stayed glued to 100 for a long time. Unfortunately, natural light isn’t nearly as cooperative or predictable as studio lights. The first couple hundred shots with this lens were absolute crap, mostly because of image quality. I was not seeing the clarity and saturation everyone else raves about. Mounting this beast on my sturdy tripod, with the VC on, I don’t find I’m happy with shutter speeds slower than 1/200th, and they need to go to 1/400 before I’m consistently happy. I do see some unnecessary softness wider than f8 as well. Recently I’ve been shooting this lens in Aperture Priority mode, and adjusting the ISO to keep the shutter speeds fast enough. I’ve also discovered that Nik Dfine does an admirable job of dealing with ISO noise. This technique is getting me into the same ballpark as the more experienced natural light shooters, though I still have a lot to learn.
The lens is so big it catches the wind. Even though I have a tripod with a head/plate system rated for 8kg, if it’s breezy there’s some shake and I’m trying to figure out the best way to hold the lens. For the most part, I keep my ball head just loose enough to move the unit around with my right hand, and then keep my left hand on the plate/head assembly as an extra stabilizer. This works well, but if there’s any kind of breeze there’s some vibration. I may need to think about investing in bean bags if I make a habit out of going out on windy days. I contacted RRS and they advised me they aren’t machining a plate adapter specifically for this lens, but the MPR-113 multi-purpose rail fits well. I can verify this claim; the rail fits very snugly to the foot without adding any noticeable bulk.
The VC spins up almost instantly, and it throws off the center of the frame. If I’m centered on something, when I spool up the VC the FOV moves just to the left and slightly above the original focus point. My 70-200 doesn’t do that; the Canon IS is completely invisible to me. It’s really not a big deal, and I’ve already begun automagically compensating for it. Once the VC is spooled up, it takes between one and two seconds before it actually stabilizes the image. I think it just takes a little while for the motors to get that much mass moving. Also related to this, running VC on this lens tears up batteries. I use a grip to double my juice and I go through a “tick” on the camera’s power meter about every 500 shots. This is a rate of consumption 3-4 times faster than I get with with my non-IS fast primes; I’m getting roughly 32GB of RAW per battery. Furthermore, since I’m using the famous “three shot burst” technique to get the mirror out of the way and absorb the slap, so I figure about 8GB of usable RAW per battery. I’m glad I’m not taking this thing miles away from anywhere; I’d have to pack a couple of kilos of batteries for a whole days shooting.
The autofocus is always willing to go longer, but it doesn’t like to come back and start hunting again. If you’ve autofocused far enough past your target that there isn’t a clearly contrasting line, the lens is not going to come back closer to look for your target. I’ve learned to flick my thumb on the focus ring to bring the focus point in front of the subject then let AF take it back to where it should be. Annoying? Yes, but for 10% of the price of Canon’s equivalent I can learn to live with it.
The lens is threaded for massive 95mm filters. I’d standardized on the ubiquitous 77mm some time ago, as that covers about 90% of the lenses ever made – all but a couple of my lenses use step-up rings to mount the filters. Until I wrote this, I hadn’t even looked up how much a decent CP is at 95mm – it’s not as pricey as I thought it would be but it’s still a major investment. While it would be nice to have it, I have a lot more to learn about technique and getting sharp, accurate shots of active wildlife before that expenditure is worth it. I was not able to locate a single 95mm » 77mm step down ring, but I put a 95 » 86 and 86 » 77 together. This setup, coupled with my 500D, gives some AMAZING magnification. These shots were taken with this setup. I really need to get a macro light mount, or hire an assistant to carry one of my e640s around and point it at the right subject though.
It’s not a perfect lens, but by any objective measure it’s performance is not as far from the “gold standard” lenses as the price is. In other words, it’s an amazing value. I’m extremely pleased I’ve picked this lens up, and while I forsee a learning curve that gets steeper the higher it goes, I’m looking forward to taking advantage of the reach and the types of shooting this gear makes available to me.