Monday, January 19, 2009

Shooting the Haas TL-15 CNC Lathe

Click to view larger
Winters are tough for photographers. When it's too cold to go outside, you end up pointing your camera at just about everything in the house. So naturally, when asked to shoot a giant computer-controlled lathe in a machine shop, of course I jumped at the opportunity.

Note: The decision wasn't actually that easy. This still required my leaving the house (remember, it's damned cold out). Had I my own giant computer-controlled lathe, I might have declined, but after 15 minutes of searching, I couldn't find one in my house to shoot, so I happily agreed.

As an engineer, I'm fascinated with machinery, so it was fun just getting a tour of JMT Machine Company. The shop recently acquired this machine, a Haas TL-15 CNC Lathe, and wanted some shots for their website and to hang in their front office. While I'm not exactly sure what I'd do with this thing, that doesn't stop me from wanting one. Unfortunately, I'm a little strapped for cash right now, and have a backlog of camera gear that's ahead of this thing in line.

Click to view largerFor this shoot, I decided to make the rather boxy machine a little more interesting by shooting up close with my Canon 10-22mm f/3.5-4.5 super wide angle lens. Now, being this close, I was (in retrospect, overly) concerned about getting the back of the machine out of focus. I generally shoot in the 30-55mm range, so I've been burned by too narrow of a depth of field in the past.

So, putting aside all of my ideas on how to shoot this thing creatively and erring on the side of making sure I got a few good snaps before leaving, I decided to be super-conservative and shoot at f/22. In retrospect, this was serious overkill. I should have known my DoF charts better for this lens - but hey, it's a learning experience, right?

If you're not familiar with flash photography, the one major difference between flash and ambient light is that, basically, only the aperture matters. You can't leave the shutter open longer to get more power out of your flash. That's how you get more out of your ambient. If you want to compete with that ambient, your only option is shoot bright and quick, not giving it the chance to burn in. Well, needless to say, f/22 eats flashes. I used a total of four strobes on this thing, spread out and each at 100% power and about eight feet away.

Here's a quick equipment check:
* Nikon SB-26, triggered by a Pocket Wizard radio flash trigger
* Canon 430EX, triggered by Pocket Wizard radio flash trigger
* Alien Bees B800 Flash Unit, triggered optically by the other flashes
* Nikon SB-28, triggered optically by the other flashes

My first thought going into this was to completely overpower the ambient lighting with a quick shutter speed and by cranking up the flash power. Well, as I mentioned, f/22 didn't leave me a whole lot of light to play with, and my first attempts at this were underwhelming at best. The flashes seemed overly artificial. Rather than stress out about that, I decided to try to use the ambient. After all - I was in a cool, grungy machine shop -- why hide it?

As it turned out, the existing light was awesome. Rows of fluorescents overhead and some powerful halogen (?) bulbs lighting up the business end of the machine when the door was open. This gave me some pretty cool color contrast to play with, while using my flashes for nothing more than fill. That suited them, considering how much they were knocked down by my choice of aperture. This gave the shot a more natural feel, adding to the shots.

At this point I had the aperture set, the flashes at the power I needed them, so the only variable left was the shutter speed, and that was all just trial and error. I ended up on four seconds. With my new, trusty, bombproof tripod (Bogen/Manfrotto 190XPROB legs and Bogen/Manfrotto 322RC2 grip action ballhead) and well, the tonnage of that machine, I was guaranteed a pretty still subject.

Overall a positive experience. I walked away with a better understanding of how deep a wide angle lens' depth of field is, how finicky optical flash triggering can be when in a large area (or outdoors), and that I shouldn't immediately dismiss the ambient light. And, the owner sent me home with some of his machined parts to shoot as I find the time.

Other equipment used during the photo shoot:
* Canon 40D
* Canon 17-55mm f/2.8 IS
* Bogen/Manfrotto 7' Pro Stand
* Bogen/Manfrotto 9' Basic Light Stand


madcatimages said...

When you shoot with an wide angle lens, you have a greater depth of field. There was no need to shoot at F22. F8 would probably have been good.
Good write up!

Blake said...

True. Not only that, but I've recently read about diffraction, which really upset me. Depending on how small your sensor's pixels are, the clarity of smaller apertures breaks down past a certain point. For my 40D, this is around f/9.5. Past that, I'm adding depth of field, (which you correctly point out is useless at such a wide angle), but I'm sacrificing clarity.