Achieving sharp images from foreground to background can be a challenge. Viewfinders can be deceiving, and checking a magnified version on the screen isn’t particularly instructive, it may indicate what’s wrong, but not the best way forward.
I know some modern mirrorless cameras have an overlay to indicate which areas are in focus, but I don’t have one of those, and I’ve also found they can be a little misleading.
This might sound a bit old school, but I do occasionally use a hyperfocal distance chart to help choose a focus distance….or maybe it’s just to check my own sanity, I’m not too sure which one. The chart can come out if I’m shooting in unusual conditions, perhaps with a different lens, or with a close foreground, and can save me from second guessing myself and taking extra photos’s I don’t need when the light is at its best.
So if you’re not familiar, here are a few pointers. Hyperfocal distance is a bit of a strange term, it’s the closest focus distance which still renders the entire background sharply. If you focus on a point closer than the hyperfocal distance, objects in the distance start to become blurred. If you focus on a point past the hyperfocal distance, more of the foreground can become blurred. Using the hyperfocal distance gives the maximum depth of focus in the image, the closest point which will still appear sharp is half way between the camera and the hyperfocal distance. So knowing the hyperfocal distance for your lens and aperture setting is occasionally helpful, over time though it does become second nature.
The hyperfocal distance is dependent on two main factors, the lens focal length and aperture, but it will also depend on the camera sensor size, resolution, and how large you will display the resulting image, if you’re only viewing small copies on a screen you probably don’t need to worry about it at all, but if you intend to print large copies, it may become more important to have sharp details from front to back.
In the scene below, which was captured with a 14mm lens (on a crop sensor camera APS-C/DX), my chart indicates a hyperfocal distance of about 2 meters at F8, which is about half way along the rock formation. That would be a reasonable place to focus because most of the foreground would then be in focus, and all the way into the background, but I still may be left short in the grass area.
If I was to narrow the aperture to F11 for a greater depth of field, the hyperfocal distance would closer to about 1.5 meters which is nearer to the close end of the rock formation. F8 is the sweet spot with many lenses, so narrowing down too far can degrade the details, F11 is usually OK, but F16 may start to push things too far, at least for larger prints. Knowing the hyperfocal distance can help optimise the focus point, and also your aperture.
A problem with the chart though, is guestimation. The tables can be pretty helpful but there are some practical limitations. If for example you found the hyperfocal distance for a scene is 2 meters away, how would you judge it? Most of us don’t carry a tape measure around. Even if you did know exactly where the 2 meter mark was, it could be difficult to focus precisely on that point with the cameras clunky focus squares (try it). Then there are variations in lens designs and other quirks which can throw the results off too, so I like to consider the charts as another tool in the kit, and a bit of a brain aid.
I could never recall the entire chart, but I do remember the distances that are most useful for my shooting, and simply understanding the principles is helpful and a time saver.
So feel free to print the tables and keep them in your bag, and just remember they’re a guide, and not an absolute. Distances are shown in either feet or meters, so be careful which charts you use. They also differ based on the camera sensor size, so choose the tables that match your camera, I’ve included tables for full frame and crop (APS-C/DX) sized sensors. At smaller print/display sizes a slight blur becomes unnoticeable, but at larger print sizes everything shows, so typically I’d use the table for larger print sizes.