Thursday, February 15, 2018

The Reflex: Tamron 55BB Lens Review

I'm a physicist by training, and an astronomy nerd at heart. The first digital camera I used (before they were even called digital cameras) back in the '90s was attached to a reflector telescope pointed at the night sky. Because of this, I've always had a soft spot for catadioptric, or reflex lenses. Most traditional camera lenses use nothing but glass to bend light in order to produce an image, but reflex lenses use a combination of lenses (dioptrics) and mirrors (catoptrics) to do so.

The main benefit of such a design is that you can produce lenses with large focal lengths that have relatively short and light bodies. My Tamron 500mm is shorter and lighter than a pro 70-200 tele zoom, albeit slightly larger in diameter. It is considerably shorter and lighter than a traditional dioptric 500mm prime lens would be. They are also excellent at managing various aberrations because considerably less of the optical path is influenced by changes in index of refraction.

There are, of course, downsides to reflex lenses, otherwise we'd see a lot more of them. They have fixed apertures that are slow compared to traditional dioptric lenses, and out-of-focus areas will take on a very characteristic, and often distracting, donut shape due to the central obstruction. Given their long focal length and slow aperture, they're not good for handheld photography in anything other than bright light, and, somewhat ironically, they can be hard to use on a tripod as well since they don't have much mass to damp any vibrations present; wind is a particular issue. Also, being something of a niche lens that has long since fallen out of favor, they haven't seen much of the way of improvements in the past 30-ish years (lesser optical performance*, no autofocus, etc.). Some companies still make them, but they tend to be geared more towards astronomers than photographers.

My first reflex lens was a new model by Bower/Opteka/Samyang, a 500mm f/6.3. Although I liked a few of the pictures I took with it, I wasn't a fan of it overall. It was very girthy (it took 95mm caps!), that extra girth didn't actually buy you any better light gathering ability (the central obstruction was so large that it performed much like an f/8), and the focus ring was too heavily damped for my taste. But what killed it for me was this: I had a really hard time getting good pictures with it. It was often so bad that I could get better results by shooting at 200mm on a kit lens and cropping to a 500mm field of view. I got a few neatly artistic pictures with it that I love, but that bulk combined with limited utility meant it had to go; I sold it to finance its replacement. Fortunately, I hadn't paid too much for it: you can find them for a little over $100 brand new.

My second, and current, reflex lens is the Tamron 55BB 500mm f/8. Although it is smaller in diameter (82mm instead of 95mm) and one stop slower on paper than my previous lens, in some experiments I conducted for the short time I had both, they both had roughly the same light-gathering power, which was a pleasant surprise. It turns out that the central obstruction in the Tamron is proportionally smaller relative to the barrel size so less light gets blocked. Unlike my previous Bower, the focus ring feels much better, and it's easy to turn throughout the entire focus range without feeling sloppy. The Tamon also feels much more solidly built, which is a huge plus for me, and focuses more closely, going so far as to bill itself as a "Tele-Macro" lens. But the biggest difference is by far in the overall optical performance. While it still suffers from the same general limitations of being an older catadioptric lens, I can actually get reasonably sharp images out of it relatively easily. I did add a short generic lens hood to help control some lens flare, but it's hardly a necessity unless you're shooting close to the sun or backlit subjects.

I say "relatively" easily because shooting with a light, fat, manual focus 500mm lens takes a good deal of practice and, ideally, a camera with good in-viewfinder focus indicators (like my Nikon D7200 has). You have a tiny depth of field unless your subject is a quarter a mile away or more, and anything out of focus turns "loopy" very quickly so getting your focus right is both tricky and important. You'll also want to try to focus on subjects that are largely parallel to your field of view for the same reason. Fortunately, most subjects that I tend to shoot (i.e. landscapes, boats on the water, etc.) are far enough away that I can just set the focus to infinity (which is clearly marked) and tweak it slightly around there as need be. Shooting surfers was hard...but I managed.

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I love this lens. While it is definitely a niche lens and will never substitute for, say, a 70-200 f/2.8 for general purpose telephoto shooting, I like being able to toss what is essentially a small telescope into my camera bag and not sacrifice much space to do so. While they haven't been made new for several decades, there are still a fair number available on the used market. My less-than-perfect example (plus the necessary Nikon adapter**) cost me about $100 at, which is just a fraction of a modern tele zoom. At that price, this lens is a steal.

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The Reflex: maybe it's not just a song by Duran Duran anymore.... 
*One important thing to note is that at the kinds of ranges you tend to use a 500mm lens at, especially over water like I do, atmospheric interference is likely going to be the limiting factor on your image quality, not your equipment.

** This lens is part of the old Tamron Adaptall-2 series of lenses. All of the lenses came with a common mount designed to accept adapters for different camera bodies. Unlike the cheap, screw-on adapter used by the Opteka and other astronomy-based lenses, these adapters are well-machined bayonet mounts and feel very solid.

Wednesday, February 7, 2018

Back To The BVI!

Two years ago, Sara and I went sailing in the BVI and the Balearic Islands. Both times it was with one other person, both times it was on 39-ish monohulls with a similar layout, and both trips were amazing. Each trip also offered something new: our BVI trip was my first trip as a skipper, and our Balearic trip was our first time in the Mediterranean.

Shortly after we booked our second trip that year, my older daughter Abby, now 13, told me in no uncertain terms that if we took another trip like this without her that she would kill me.*

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Not being one to tempt fate, or the temper of a 13-year-old-girl, I am happy to report that we will be cruising in the BVI for a week this summer and that we will be doing so without pain of death hanging over me. And like our past two trips, this one also has new things to offer. Although this will be our third time in the BVI, this will be my first time skippering a catamaran, my first time skippering with an appreciable crew (we're bringing some family along), an my first time skippering overnight with kids aboard.

But despite our excitement, this trip will be doubly bittersweet. Last September, Hurricane Irma devastated the Caribbean, with the BVI being particularly hard hit. Although rebuilding is already well underway, I expect that we will still see much of the remaining devastation and reconstruction. I'm hoping that our tourism dollars will help with the recovery. It will also be our first time back since the loss of Sara's mother to cancer a month after our last trip there. I'm hoping to hit a few of the same spots with other members of her family so that they can share our memories of her.

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So, watch this space. Adventure awaits this summer!

*And I kinda believed her.... 

Wednesday, January 17, 2018

On Cameras

As I've taken and shared more and more pictures, I've been asked two questions with increasing regularity:

1. What kind of camera did you use to take that picture?
2. What kind of camera should I buy?

I'd like to take a moment to address both of those questions here.

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What kind of camera did you use to take that picture?

When I was getting a print of the above picture framed, the lady behind the counter asked me if I used some kind of special camera to take it. Although I politely told her what I used, the correct answer would have been to tell her that this is the wrong question to be asking. It's like asking a chef what kind of pan they used to prepare a delicious meal, or what kind of brush an artist used to paint a masterpiece.

There are a lot of things that go into making a good photograph. Things like lighting, timing, and positioning are all far more important than what camera the photographer is using. In the image above, the sun is setting behind me and casting a golden glow across the harbor. There is also a harbor wall behind me shading me from that golden glow, making the foreground look darker and bluer. In essence, the sun has set further on me than it has on the other side of the harbor. It's this combination of lighting, timing, and positioning that created the contrast of light and color that make this image so interesting, not the camera I used. And it took knowing all of those things (or, in this case, being with someone who knew all of those things*) to capture that image, not a specific camera.

The camera is just a tool. It can't take good pictures, only the person using it can do that. Taking good pictures requires experience, patience, and a little bit of luck, not a good camera.

What a good camera does do is make it easier to take good pictures. This is why pros buy top-end cameras, not because they take better pictures. The easier it is to use, the less distracted the person using it will be and the more focused they'll be on taking pictures. Which leads me to my second question:

What kind of camera should I buy?

This is also the wrong question. What you should be asking yourself is what you need a camera to do. If you're interested in shooting portraits or weddings, using the kit I use to shoot racing sailboats would likely leave you woefully unprepared. And even if you are shooting racing sailboats, using my kit without knowing what I've learned about it could leave you almost as unprepared.

I don't like to tell people which camera to buy, but I will tell people who are starting out what I think they should look for in a camera. Don't look at your camera purchase in terms of specific features, but to look at what you can learn from it. Think of it as the first car that parents buy a teenager who just got their license; they wouldn't likely buy that kid a Ferrari, right?

Your first camera is a tool, as all cameras are, but it will also likely be your first teacher. Pick a camera that gives you options to learn and gives you room to grow. To me, this means three things:

It should be cheap.

It should have interchangable lenses.

It absolutely has to allow for full manual control.

This is exactly what I did, although I didn't realize it at the time. My first "real" camera was a refurbished, out-of-production Nikon D3100. (I wrote a 'blog post about my first camera and what I liked and disliked about it at the time here**.) I had no clue what I was doing, but after using that D3100 for about a year, I felt like I had learned enough to know what would be a good choice for my next camera. I bought another Nikon, a D7200, because it was (and still is) the best mix of features for what I need on my budget. How did I know that? Experience. I knew what I needed by not having it (in my case, better weather-proofing, better autofocus, and easier ways to change settings among other things), not because someone else told me.

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This picture is single most popular image on my Instagram feed by a substantial margin at the time of this post. It was taken with that cheap, refurbished, out-of-production, entry-level D3100, not the more expensive camera.

It's not about the camera. It's about the photographer.

A camera is just a box that collects light. Learn to work with the light.

* Big 'ole shout-out to Kat Hanafin at The Nautical Collection for putting me in the right place at the right time to take that pic. After almost a year, I did manage to recreate the effect on my own in this pic. Thanks Kat.

**At some point I may need to go back and update that post with more things I've learned. Given my recent posting rate, that'll be sometime in 2020. Heh.