Wednesday, May 16, 2018

Workhorse: The 70-200 f/2.8

The 70-200 f/2.8 is a photographer's workhorse lens, the telephoto end of the "holy trinity" of fast zooms*. It is an incredibly versatile lens because it lets you get pictures of things that are far away, or to take portraits where the background just melts away into a silky blur. I had a lot of photographers tell me that this is the single most important lens in a pro's bag, and I didn't really understand it until I shot with one.

And they're right, of course, which is why they're pros. Nothing I can say will really explain it, you just have to try one to really understand.

Now, in spite of that, I don't own one yet. I've been renting them when necessary because, from a purely business standpoint, buying one outright hasn't made financial sense yet. I've also been renting different versions so that I can get a feel for which one I'd like to eventually buy. To date I've tried out the following:

Nikon 70-200 f/2.8 VRII

Nikon 70-200 f/2.8 FL
Tamron 70-200 f/2.8 G2
Nikon 70-200 f/4 (I know it's not an f/2.8, but I'm a sucker for lightweight lenses)

I'm not going to spend a lot of time doing detailed comparisons of optical performance other than to say that they are all very good because other, far more qualified folks have done that to death (plus, I never had all of them at the same time to do a real side-by-side). But I do want to share a few things that I learned about them.

Build Quality

The Nikon VRII and the noticeably lighter Nikon f/4.
The first thing you notice when handling a 70-200 f/2.8 is the size and weight of them. They are generally built like tanks and would likely serve just as well as a blunt weapon as a photographic tool**. This is part of why pros love these lenses: they're reliable. The f/4 isn't nearly as ruggedly built and is much lighter. This is great if space and weight is at a premium for you and I could see using one if I were hiking, climbing, etc., but out on a bouncing chaseboat, I always had a mild fear of breaking it in the back of my mind. I never had this fear with any of the f/2.8s. For this reason alone, the f/4 is generally not suited for my needs, even though it is a great performer optically and in other regards.

Smooth Zooming

The zoom rings on all of the Nikon lenses have a very consistent feel to them: light enough to zoom easily, but not so light as to shift focal length should you take your hand off of the ring. The zoom ring on the Tamron lens, on the other hand, is stiffer and takes a bit more effort to turn. None of them feel bad to me and I suspect that liking one or the other will boil down to personal preference. For me, shooting the Tamron on land feels better because it feels more precise, but the Nikons feel better on the water because I'm already expending that much more energy just to steady myself that every little bit of reduced effort helps. I suspect that the zoom ring on the Tamron will loosen up over time as zoom rings are prone to do, but ideally I'd like it to be a bit looser now.

The Ring of Power

Speaking of zoom rings, not all of them are located in the same place. On Nikon's VRII and f/4, the zoom ring is located closer to the camera, and on Nikon's FL and Tamron's G2, the zoom ring is closer to the front element. Two of these arrangements feel quite natural and balanced nicely, the other two not so much.

The f/4 is just about perfectly balanced for a smaller body like the D7200 I used it with. It doesn't have a lot of weight out front, so keeping your grip closer to the body keeps the whole camera well balanced. Likewise, the Tamron G2 is also very well balanced for a smaller body; with more weight from the heavier lens out front, moving your hand further forward on the lens keeps the weight distribution right. Also, and very importantly, the focus ring on the Tamron is placed such that your hand doesn't tend to rest on it (at least not my hands), so having my hand that far forward doesn't interfere with the focus.

Nikon FL, as deployed.
The VRII feels very front-heavy with a smaller body. I suspect that it's definitely designed with a heavier body in mind. This poor balance seemed to wear my arms out faster while shooting, which was an issue being on a boat all day. Nikon changed this with the newer FL model, possibly in anticipation of lighter mirrorless bodies in the future. But in doing so they placed the focus ring right where the palm of my hand seems to naturally rest, meaning that I had to come up with a creative solution (which I describe below) to avoid throwing my focus off. This awkward placement of the focus ring really hits the FL in the ergonomics department despite the better overall balance with a smaller body.

Feet of Strength

With the VRII, my preferred method of deployment is simply to remove the tripod foot from its collar and attach my cross-body sling to the tripod mount that remains in the collar. This makes for a very slim setup and balances well while by my side, and it doesn't get in my way while shooting. Nikon really got the tripod collar right on the VRII and FL; I wish someone would come up with a similar version for the Tamron or other lenses.

Nikon FL, foot rotated. See how it rested on my palm***?
I deployed differently on the FL because of the focus ring issue. I settled on leaving the foot attached, but rotating the foot to the left so that it covered the switches and attaching my sling to it. This had the benefit of protecting the switches from being accidentally flipped (which isn't a big deal for Nikon lenses, those switches are pretty stiff), but more importantly it allowed me to rest the palm of my hand on the tripod foot instead of the focus ring. Viola! No more focus ring issues. The downsides to this are a slightly clunkier rig and a bit more fatigue for my left hand from arching my palm slightly. Mind you, this works with my hands, if you have smaller hands it may not. (Then again, if you have smaller hands, the focus ring placement may not be an issue for you in the first place, so....)

Nikon FL @ 75mm, f/2.8, ISO 400, 1/200sec.
A similar setup (tripod foot left attached and rotated over the switches) works wonderfully for the Tamron G2 as well, but for a different reason. The switches on the Tamron lens are a bit looser and more susceptible to accidental switching, so having that tripod foot guard them works quite well. Also, the geometry of this setup feels much more natural on the G2, so it didn't tire out my hand like it did on the FL. (Again, your hands may vary.)

Although the Tamron lacks the cool removable tripod foot of the Nikons, it does have an Arca Swiss mount built into it's tripod foot, so it's easier to actually attach to a tripod. (The whole collar is also removable, but the lens seems rather awkward without it on.) I feel like an ideal tripod mount for a 70-200 would combine the easily detachable foot and permanent collar with a secondary mount of the Nikons with the built-in Arca Swiss mount of the Tamron.

The f/4 has an optional tripod collar, but I suspect that using it would be largely a waste. The lens is so light that the camera body's tripod attachment point should works just fine for a cross-body sling and should work equally well for tripods.

Hippy Hippy Shake

Tamron G2, as deployed, just like the FL.
Image stabilization is important for telephoto lenses if you're not shooting with a tripod. I didn't do detailed measurements of the performance of the different lenses, but I will say that they all allowed me to make sharp, hand-held shots that would have been impossible otherwise. One distinct observation that I do have though is the general feel of the various image stabilization systems and how they look through the viewfinder.

The Nikon systems tend to jump around more as I'm composing a shot. This has no impact on the final image as it still freezes the frame when the shutter is released, but it does sometimes make composition trickier. Also, if I were to shoot video (which I rarely do, at least through lenses like these), I imagine the video would likewise be jumpy. Nikon seemed to design their system with minimizing power use and instantaneous, instead of continuous, performance in mind, which makes perfect sense for a still camera.

On the other hand, the Tamron system held the image much more smoothly over time. When looking through the viewfinder I had an easier time composing shots, and I imagine that video shot through the Tamron lens would be smoother as well. In terms of overall usability, I definitely prefer the image stabilization of the Tamron lens.

Tamron G2 @70mm, f/2.8, ISO 200, 1/400sec.
One potentially related observation here is that my camera's battery seemed to drain a bit faster with the Tamron G2. Maybe that extra smoothness in the image stabilization came at the expense of increased power draw? This would make sense because it seemed like the Tamron's image stabilization system was running running harder/longer than on the Nikons. Or maybe my batteries are just getting old. Again, I haven't gotten to do a side-by-side test, but I wanted to mention it anyways.

The Almighty Dollar

The difference in price between these lenses is wholly non-trivial. The Nikon f/4 and the Tamron G2 are both about $1,400 when bought new. The Nikon VRII was last available at $2,100 new but isn't in production anymore, and sells used for about $1,400.

The Nikon FL sells new for a whopping $2,800. I could buy two of the other lenses and have one as a backup for the price of a single NIkon FL!

Price-wise, the VRII felt about right to me when you could still get it new. Paying a premium for the factory warranty and Nikon reliability would have been worth the extra money. I'm not opposed to buying refurbished or used (in fact, most of my gear is refurbished), but for a major investment like this I'd rather buy new for the factory warranty. This means I probably won't be buying a VRII.

Business end of the Nikon FL
I cannot see myself being able to justify a $2,800 pricetag for any piece of equipment anytime soon, even to get that warranty and legendary Nikon durability. I simply don't make enough money with my photography yet to justify such an expense. Sorry Nikon, you priced yourself right out of my market with that one. I'm sure that full-time pros will still buy it, but for side-gig photographers like me, it just doesn't make financial sense.

As I mentioned above, the Nikon f/4 isn't rugged enough for my needs, so that's a no-go as well in spite of it's comparatively low pricetag and great optical performance.

That leaves me with the Tamron G2. It's rugged, it's ergonomics are right, it's image stabilization is top notch, it's price is reasonable, it's still available with a full warranty, and it produces great images. I think this puts the Tamron G2 into a sweet spot in terms of value and performance for me as a part-timer. I have some reservations about its long-term reliability since it is coming from a third party manufacturer, but the lower cost and 6 year warranty help balance those reservations out. Once I get my income stream a bit more solid, I'll almost certainly be buying one.

*The other two being the normal zoom and the wide zoom in f/2.8. Most current normal fast zooms are 24-70, and the wides vary by manufacturer, but Nikon's is 14-24.

**I do not, under any circumstances, recommend or condone the use of expensive photographic equipment as a blunt weapon. Or, for that matter, beating people with blunt weapons in general.

 ***I cannot quite emphasize how tricky it is to take a picture of yourself holding a camera with a heavy lens, one handed, with a second camera, also one-handed. Heh.

Monday, May 7, 2018

Lens Sharpness or: How I learned To Stop Worrying And Love The Lens

There are a lot of ways to quantify the performance of a lens.

One standard method is the Modulation Transfer Function, or MTF.  Without getting into the technical details, MTF charts can be used to represent a lens's optical performance: a horizontal plot means that a lens will produce an image equally sharp at all points across an image plane, whereas one that drops off will be less sharp away from the image center*.

Another handy resource to use are websites that do standardized testing of lens performance, one of which is DXOMark. Here you can get plots of lens performance at various apertures, including sharpness, transmission, vignetting, etc. You can even get everything rolled up into a single score for the lens. Handy, right? a point. Something I've run across is photographers judging lenses as inferior simply because their MTF plots aren't good enough or their DXOMark scores aren't high enough. While I'm all for using these resources to learn about my gear and its limitations, they are just that: resources. They aren't meant to be end-all-be-all judgements on the superiority of a lens because there is so much more to consider when choosing a lens than pure optical performance in a technical sense. I'd like to take a moment and call out a few factors that aren't included in these measures.


Bokeh! Shot wide open at f/1.4.
If you're trying to isolate your subject using a narrow depth of field, you likely want those areas to be as out of focus as possible. The pleasing quality of these out of focus areas is called "bokeh". If you're using a more advanced lens that is tack-sharp, corner-to-corner you can achieve pleasing bokeh, but it's also possible that any out of focus highlights will render so sharply as to be distracting. However, if you're using  a simpler lens design that is a bit softer away from the image center, you may have a better chance of getting pleasing bokeh because those highlights will be softer. This is why some portrait photographers still love simpler lens designs. Conversely, this simpler lens may not be an obvious choice for shooting landscapes or architecture, where your subject is likely to be taking up the entire frame and you want it all to be in focus. And the thing is, this is all subjective, and it isn't necessarily constant either. A lens can render amazing bokeh in certain circumstances and be decidedly "meh" in others. And what one photographer sees as great bokeh could be not what another one is looking for. Like all art, it's largely subjective.


Polygonal bokeh can be distracting. Shot at f/2.
Part of what determines the "feel" of bokeh is the configuration of a lens's aperture. The rounder the aperture is at a given setting, the "softer" the bokeh will generally be. As a result of this, many lens manufacturers have lately been shifting more and more towards using rounded aperture blades. This is great for bokeh, but the price you pay is often the inability to produce sunstars**. Sunstars are those brilliant, pointy stars that get produced by bright points of light on longer exposures when shooting through a small, polygonal aperture. One of the reason I love older Nikon lenses is for their odd number of straight aperture blades that produce amazing sunstars when stopped down. The tradeoff is that the bokeh on these lenses can be somewhat harsher when shooting at faster apertures because highlights render as polygons instead of circles.
Sunstars! Shot at f/8 on a tripod.

I am a total sucker for sunstars, the donut-shaped bokeh of catadioptric lenses, or any other kinds of optical oddities that lenses produce that you can't just "add in post".  They can be distracting in certain circumstances obviously, but when used right, they add a touch of magic.


Lens design has come a long way since the first SLRs revolutionized photography. Computers have allowed for more complicated and precise optical designs, more advanced optical coatings help ensure superior transmission and reduce aberrations, and autofocus systems have gotten faster and more accurate. Well, guess what? All of this engineering means that lenses have generally gotten bigger and heavier too. As someone who enjoys shooting small, fast primes, the idea of toting around some of the newer, heavier offerings for most work isn't really appealing to me in spite of their superior optical performance. Why? Because a photo that you missed because you were too tired or sore from lugging around a heavy kit is always less sharp than one you actually took. On the other hand, if I can limit my kit to just one or two large, heavy lenses and still get the job done without limiting my creativity, that works too. It's a balance, and striking the right balance depends on what you, the artist, needs.

A Lens Is A Tool

My favorite lens. Not in spite of its "flaws", but because of them.
What does this all mean? It means that a lens, just like a camera, is a tool, that different tools have different strengths and weaknesses, and that judging a lens by measuring it along only one axis of performance will likely limit your creativity. My Nikon 50mm f/1.4 AF-D is my favorite lens. It is tiny, is fantastically sharp when stopped down, and produces amazing sunstars, but faster than f/2.8, it gets...quirky. Bokeh is super-soft wide open at f/1.4, but has a weird harshness from f/1.6 down that goes away by f/2.8 due to the straight aperture blades. And faster than f/2, getting your subject sharp is hard because your depth of field is paper-thin, and chromatic aberration tends to soften even things that are in-focus. It's MTF charts reflect this quirky behavior, and at first glance it seems decidedly "meh".

Does that make it a lesser lens than more modern 50mm lenses with "better" MTF plots at faster apertures and higher DXOMark scores? No. It only makes it a different lens. I would consider a newer lens with rounded aperture blades for a studio portrait shoot, or a more rugged lens with better weather-sealing for use on the water, but for candid or street photography, where small size is a virtue, or landscape shots, where stopped-down performance reigns and sunstars can add a nice creative flare, it is absolutely perfect.

Photography isn't just about producing the sharpest possible image. It's about translating your artistic vision into an image using the proper tools.

Know your tools, and choose them wisely.


I have become a huge fan of "try before you buy". I've been renting 70-200 f/2.8s for racing shoots for about a year now, and I realized that I was wasting a huge opportunity by always getting the same lens. If I really wanted to know my tools, I should be trying different ones. So, as much as I love the Nikon 70-200 f/2.8 VR2, I branched out and started trying other offerings, and I've learned a lot. I also have a few other rentals coming up for other occasions. Stay tuned for my write-up of these experiences!

*Assuming your MTF plot is vs frame position. Other fields outside of photography will often plot them vs frequency.

** Some manufacturers have managed to produce apertures that are round when wide open for good bokeh but polygonal when stopped down for good sunstars. I try to find these whenever I can....