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Days 342-343/365: Depth of Field Experiment

It was a pretty uneventful weekend, made up of all the usual stuff. Consequently, I had to search around for opportunities to take photos. My husband has one of those exercise bars in the house and the boys like to try it out from time to time. Here is Rexy doing his best to hold on as long as possible. 

The boys played a lot of Minecraft, which made them feel very happy indeed. It made me feel like a bad mother. It is very difficult to please everyone I guess. 

I was feeling slightly more creative today. I was inspired by a video tutorial I watched this weekend. It was by Brian Smith. I am going to have to get his wonderful looking book.

I also felt inspired to try a little photo experiment that I have been interested in for a while. I have been wondering about depth of field. I think that the thing that I am curious about is called the area of confusion. How appropriate! Basically, I am unclear whether the area in focus is as far deep as it is wide? In other words is more of a two dimensional circle than a perfect sphere? The reason I am so interested in this is that I have noticed over the year that two people side by side can be in focus but any movement backwards or forwards and they are totally out of focus. It is so annoying when photographing multiple children. Bear's birthday cake really highlighted this issue for me as I couldn't get all of the princesses in focus. 

So I got the girls out again for a little photo experiment. I also wanted to play around with focal length to see if that made a difference. All of these photos were shot a various focal lengths as shown, but I cropped to see what the focus was like. I used the tripod/LED screen/zoom in to focus method because I love it for stills. 

The first three were shot at f/2.8 and the focus was on Belle's face. The first image was taken at 24mmm, the second at 50mm and the last at 70mm. I did move in closer or father to get roughly the same shot though. That's the one on the right dressed in yellow, in case you don't know your Disney Princesses. I would expect the other two to be out of focus but Rapunzel (in purple) actually did pretty well. 

This second lot were shot at f/5.6 and again the focus was on Belle's face. The first image was taken at 24mmm, the second at 50mm and the last at 70mm. I would have expected f/5.6 to have done a good job at getting them all in focus, but Snow White has definitely fared worse than the other two. The focal length didn't make as much difference as I expected. 


 I will have to revisit this idea I think. It is pretty clear to me now that distance in width does not equal distance in depth. I might post a question on Clickin Moms.