Funny Physics – Shooting Reflections

Posted on May 31, 2011


Other Car Galleries:

How to Shoot Hot Rod Reflections

I like hot rods, old cars, and in general great examples of Detroit rolling iron. I go to a lot of car shows and take photos.  Having the cars all lined with people around has it’s challenges. For one, you have to be so close to get the shot that you are generally reflected in the car. I have one Buick Eight image where I’m in the shot at least nine times, once for every “tooth” in its “million-dollar smile.”

Self Portrait in Million Dollar Smile

But there are also some interesting upsides. One thing I look for a lot is interesting images, either one car reflected in another (see the link in the right navigation for some of my favorite car images), or skies and buildings.

Early Reflection

One thing it took me a while to figure out is that if you want the reflection of the sky to show in focus in the final image, then you need to set the lens on infinity. If you focus on the car which is four feet away, the reflection will not be in focus!

Focus on the car, and the clouds go fuzzy

But if you focus on the sky it will:

Clouds in a Sea of Red

I remember when I discovered this and informed Bernard he said “Of course.” Well, that’s one of the issues with being a mathematicaster, it takes a long time to figure out things obvious to the more naturally talented.

The caveat to this is that I have one lens, an inexpensive 28-200mm zoom which has a minimum focal length of 2m.  (Inexpensive, but every photo I ever sold came from it, even “cheap” glass these days is amazing.) That means that if you are less than ~6′ away from the object then the autofocus mechanism of the camera will “hunt” and not let you take the shot. (I actually have some eagle pictures where I was so close I had to back up to get him with that lens.)

However, I learned this weekend that I can be closer than that to a car, as long as I’m focusing on the clouds in the reflection which are at infinity. Is that geeky cool or what? Just another example of you have to really know what your camera is “thinking” when you take a shot. You just have to have enough light to stop the camera down for the depth of  field (DOF) that gets you both the car and the sky and still handhold it. Usually I’m shooting these at f22 or so, the minimum for that lens. Hardly a problem in any case where you have the reflection to shoot.

Infinite reflection

One other interesting thing I ran across. I was shooting this perfectly painted black car:

Perfect Paint

Which had a very cooperative owner. I’ve always wanted to do a series of cars with their owners reflected in them and call it “The Ghost in the Machine.” So I lined him up for a snapshot. This shot is cropped so tight and the paint is so good, you can’t even tell what color the car is! I have to think about that some…It looks like in addition to focusing on the reflection, I’ll need to also meter on it (these shots are all pushed a little to the right and not post-processed anyway). To which Bernard will say “Of course!”

Ghost in the Machine 1

Anything that is worth shooting is worth shooting twice.
Please leave comments on the blog if you can!