How do they do that?



Focus is a critical element in any photograph. Have you ever noticed a picture

where everything seems to be in focus from the foreground to the horizon? The

trick is to use "hyperfocus." The September 1996  issue of "Popular Photography" gives

this explanation: "Simply put, the hyperfocal distance is the focusing point at

which the lens must be set to provide the maximum depth of field at any

aperture." (page 64).



Hyperfocal scales once were printed on lens barrels but those helps are rare

today. You could use a hyperfocal depth chart or remember the mathmatical

equation ("...square the focal length, take four percent of this figure and

divide the result by the f-stop") or use your Newton and Hyperfocus Calculator.

Simply fill in the lens focal length and the f-stop. The calculator will tell

where to focus your lens and it will also tell you how much of your scene

should be in focus.



For example, if you are using a 50 mm lens at f-11, the calculator will tell

you to focus on a point 30 feet away. Everything from 15 feet to infinity should be

in focus. The calculator will also allow you to play with the variables. If you

stop down from f-11 to f-22 the calculator will tell you to focus 15 feet away

and you should have everything from 7.5 feet to infinity in focus.



The Hyperfocus Calculator has been tested on the original Message Pads. Please

send "Bug Reports", suggestions and comments to JohnMcKeel@aol.com. Note: This

calculator only works with 35 mm cameras and since this program is "freeware"

the usual disclaimers apply. You are on your own but I'd love to hear from you.

I'm working on a number of photographic applications for the Newton. If you

would like to be notified, please contact me. If you would like a version of

this program for medium and large format cameras, please send your camera to me

<GRIN>.



Thanks to Ken Williams, Herbert Keppler and Popular Photography magazine.