Paul Lange
Moderator
I've written short tutorial on Hyperfocal Focusing and a the link to a downloadable Excel sheet that does the calculations for you.
Although there is loads of maths and theory behind hyperfocal focusing here we will just stick to how it is useful to us photographers. Quite simply it is a method of focusing your lens so that everything from a set distance in front of you ( half your hyperfocal distance in fact) to an infinite distance way off in the background of your photograph is in focus. With super wide lenses (typically 8mm to 24mm) the distance in front of you can be less than a foot. As the focal length of your lens increases this front focusing distance will increase. Aperture also has an effect on your front focal distance, the smaller the aperture the closer to you it will be. Lenses used to have charts built into them so you could easily set your lens to its hyperfocal distance very easily. You just set your aperture and turned the focus until the infinity sign aligned to your selected aperture mark on the right hand side of the little aperture scale on your lens. The aperture scale will read something like this:
So if you decided on f11 you would turn your lens focus until the infinity mark on your focus scale aligned with the 11 on the right hand side of the aperture scale. However nowadays you don’t get this very often and have to resort to carrying a chart or memorising the numbers. To complicate it even more many digital DSLRs have a crop frame sensor that means that the hyperfocal distances are different from full frame camera or 35mm film SLRs. The scales on the lens usually only work with film or full frame sensors. Here is the download to a handy Excel spreadsheet that calculates your hyperfocal distances for a variety of focal lengths and f-stops. Just follow the instructions on the sheet and print it out and keep it handy. To use you simply find the hyperfocal distance (in feet) that corresponds to your focal length and f stop and manually focus the lens to this distance.
Download - www.realphotographersforum.com/downloads/paul_lange_hyperfocal_calculator.xls
A screen shot
You’re almost ready to go however there is a but, well actually a few. First I suggest you get to know your lens. I have a Tamron 10mm –24mm that is capable of excellent results but only on a selected range of focal lengths and apertures. My lens is usable from 10mm to 20mm and only at apertures f5.6 to f11. Searching the web for technical review information and wrapping your head round it is really key to hyperfocal focusing. This is one nugget that you probably won’t find elsewhere. You will most likely end up with disappointing results if you don’t take this on board.
The hyperfocal distance is calculated based on something called acceptable sharpness. This defines the boundary where the image is determined to still be in focus. Although this was all worked out by someone very clever it is still based on some ones opinion of what they consider to be acceptable. With very high quality lenses this is good enough. However if you own just a good-ish lens (like my Tamron) then it may not be acceptable. Here is the second nugget, choose your aperture, dial in your hyperfocal distance and then close your aperture down by one stop. Your close focusing distance will be a little further away but overall your image will be a little sharper as a result. The caveat here is that (in the case of the Tamron) the new closed down aperture must not be more than f16 as at f22 diffraction begins to have an effect on image quality. Also for the longer focal lengths the foreground may be out of focus. However for short focal lengths the close focus distance is often unnecessarily close anyway.
Although there is loads of maths and theory behind hyperfocal focusing here we will just stick to how it is useful to us photographers. Quite simply it is a method of focusing your lens so that everything from a set distance in front of you ( half your hyperfocal distance in fact) to an infinite distance way off in the background of your photograph is in focus. With super wide lenses (typically 8mm to 24mm) the distance in front of you can be less than a foot. As the focal length of your lens increases this front focusing distance will increase. Aperture also has an effect on your front focal distance, the smaller the aperture the closer to you it will be. Lenses used to have charts built into them so you could easily set your lens to its hyperfocal distance very easily. You just set your aperture and turned the focus until the infinity sign aligned to your selected aperture mark on the right hand side of the little aperture scale on your lens. The aperture scale will read something like this:
So if you decided on f11 you would turn your lens focus until the infinity mark on your focus scale aligned with the 11 on the right hand side of the aperture scale. However nowadays you don’t get this very often and have to resort to carrying a chart or memorising the numbers. To complicate it even more many digital DSLRs have a crop frame sensor that means that the hyperfocal distances are different from full frame camera or 35mm film SLRs. The scales on the lens usually only work with film or full frame sensors. Here is the download to a handy Excel spreadsheet that calculates your hyperfocal distances for a variety of focal lengths and f-stops. Just follow the instructions on the sheet and print it out and keep it handy. To use you simply find the hyperfocal distance (in feet) that corresponds to your focal length and f stop and manually focus the lens to this distance.
Download - www.realphotographersforum.com/downloads/paul_lange_hyperfocal_calculator.xls
A screen shot
You’re almost ready to go however there is a but, well actually a few. First I suggest you get to know your lens. I have a Tamron 10mm –24mm that is capable of excellent results but only on a selected range of focal lengths and apertures. My lens is usable from 10mm to 20mm and only at apertures f5.6 to f11. Searching the web for technical review information and wrapping your head round it is really key to hyperfocal focusing. This is one nugget that you probably won’t find elsewhere. You will most likely end up with disappointing results if you don’t take this on board.
The hyperfocal distance is calculated based on something called acceptable sharpness. This defines the boundary where the image is determined to still be in focus. Although this was all worked out by someone very clever it is still based on some ones opinion of what they consider to be acceptable. With very high quality lenses this is good enough. However if you own just a good-ish lens (like my Tamron) then it may not be acceptable. Here is the second nugget, choose your aperture, dial in your hyperfocal distance and then close your aperture down by one stop. Your close focusing distance will be a little further away but overall your image will be a little sharper as a result. The caveat here is that (in the case of the Tamron) the new closed down aperture must not be more than f16 as at f22 diffraction begins to have an effect on image quality. Also for the longer focal lengths the foreground may be out of focus. However for short focal lengths the close focus distance is often unnecessarily close anyway.
