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   This calculator provides near, far and hyperfocal distance for any specific lens and film format inputted. It also provides a Depth-of-Field Table showing the zone of sharpness for the inputted lens at different distances and f/stops.

Lens Focal Length Conversions By Format Table
    Ever wonder what lens equivalent you would need if you were shooting a different format film? With this table, you can easily tell that a person shooting 6x7 would need a 210mm lens to see the same thing you do with a 105mm on your 35mm system.

Adjusting Exposure For Teleconverters And/Or Extension Tubes
    If you use either Teleconverters or Extension Tubes and you have TTL light metering, you normally do not worry about how much light you are using. But what if you TTL light meter goes on the fritz or you just wondered how much light you loose? With this calculator you can find out what your effective aperture is for any combination of lens, teleconverter and/or extension tubes.

Resolution and File Size
    Want to know what your file size will be as either a RGB or CMYK image at various print sizes? You can use this calculator to find the file size for various output resolutions in ppi (dpi).

Focal Length Needed Calculator
    You know what size and how far away the subject is, but what focal length lens do you need to use to fill the frame using your current format?  There are a lot of ways to use this calculator, you can input the focal length and size of the subject and find out how far away you need to be to fill the frame. You can also specify if you are using vertical or horizontal formats for a variety of film formats.

Angle of View Calculator
    Would you like to know what the angle of view is for any lens for a given format? In diagonal, horizontal and vertical angles? This simple calculator will let you know.

Flash Calculator
    Enter the Guide Number of your flash and how far you are from the subject, this calculator can tell you what aperture to use at various ISO's and flash powers (of course you can calculate other combinations).

f / Number Arithmetic
    Have you ever wondered what f/stop you would need to use if you lost 3 stops of light? Or what f/stop should you set if someone asks you to subtract two stops? Use this calculator to find the answers.

Scanning & Printing Calculators
    Want to know how big your file size will be if you scan a 8x10 original at 300 dpi and 24 bit color depth? How about printing a digital file of a known size, what size in inches will it come out as? There are also calculators so you can figure out how to scan an image for printing at a specified size and another for screen display.
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|    Depth-of-Field    |    Focal Length Conversion Table    |
|    Teleconverter & Extension Tube Exposure    |
|    Resolution and File Size    |
|    Focal Length Needed    |    Angle Of View    |
|    Flash Calculator    |    f/Number Arithmetic    |
|    Scanning & Printing Calculators    |
|    Calculator Home    |

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    This website is published by the OREGON COAST PHOTOGRAPHERS' ASSOCIATION, Inc. All articles, features, images and other material posted within do not necessarily reflect the views of OCPA’s Board of Directors, officers, membership, associated organizations or editors of this publication. Any/all brand, product or business names listed are copyrighted, trademarked and/or registered and are not necessarily endorsed by OCPA.
Reprinting / reposting of any article or web page, in whole or in part, from this site may be used in non-commercial photography club newsletters or web sites as long as the item is not specifically copyrighted and credit is given to the author and this web site as the source of the information. Any other type of reproduction may be done with specifically written permission only.
Inquiries about this publication may be made by directing them to the webmaster, c/o Oregon Coast Photographers’ Association, Inc., P.O. Box 5646, Charleston, OR 97420 or

Copyright © 2002-03 OREGON COAST PHOTOGRAPHERS' ASSOCIATION, Inc. All rights reserved.
Version: 1.0
Revised: October 20, 2002