My time here in Cripple Creek has led me to reevaluate some fundamental rules I have used to get good images since my early film days with my manual focus Minolta X-700. Over the last decade and four Canon digital camera models, my circumstances and technology have changed considerably. The specific fundamental rule I am thinking of is the shutter speed versus focal length rule of thumb for sharp pictures, “minimum hand held shutter speed equals 1/focal length”. So, if you are shooting all the way zoomed in with a 200mm lens, your minimum shutter speed would be a 200th of a second.
The rule of thumb held true with my first digital camera, the original Canon 1D and my consumer grade 300mm Canon lens. That camera was only a 4.5 mp CCD sensor version, creating a native 300ppi image of around 5″ x 8″, pretty similar to the 35mm film versions of old. That guideline continued to hold through my 10D and then my 10mp 40D, although in the meantime I had purchased my amazing Canon 70-200 F4L lens with four stop F4L image stabilization technology.
Then came the 20mp Canon 70D camera body… However, Woodland Park is in a valley, everything I wanted to photograph was nearby and life was good. Even Pikes Peak was practically in my back yard, usually requiring no more than 100mm of focal length. However, the move to Cripple Creek has changed things considerably, at least for local photography projects. The Sangre de Cristo and Collegiate Peak mountain ranges are 60 to 100 miles away and I almost always shoot them fully zoomed at 200mm in the faint early morning light. As a stock photographer I review all images at 100% in Photoshop and I am starting to notice some disappointing results. So recently I have been conducting some focal length versus shutter speed tests, only to raise more questions than I have been able to answer.
After a good amount of research it has come to my attention that our high tech improvements have brought about the need for some changes in my shot planning. For starters, my 70D has a 1.6 crop factor. In other words, the sensor is only .6 the size of a full frame 35mm camera and that has to be taken into consideration, changing the shutter speed calculation to 1/focal length * crop factor. My 200 mm lens is now the equivalent of a 320mm lens, reducing the minimum shutter speed to 1/320. Of course the four stop IS can be taken into consideration, although I’m not sure I can count on always being able to reduce my shutter speed by four stops.
Also requiring consideration with the latest generation of cameras is the incredibly small pixel size required to fit 20 million of them on a sensor, not to mention what it takes to accommodate 50 million pixels that some of the more expensive models might be sporting! Such tremendous resolution not only shows the finest image details, it also reveals the most minute flaws and camera motion. I was not able to come up with a new and infallible rule of thumb, however I did learn enough to know that my old assumptions are out the window with yesterday’s technology. I also learned that it will be a good idea to lug my Manfrotto along a lot more often, and to make sure to keep my shutter speeds up when I am required to hand hold my camera during important projects. My new unofficial aspiration is going to be to try to shoot with 1/400th or maybe even 1/500th of a second when I am shooting at 200mm focal length. Of course that is not always going to happen, especially when I am shooting wildlife early in the morning. However I will be paying a lot closer to my ISO values during those shoots. Definitely don’t want any more of those 1/30th speeds!