Photo Technical

Understanding the connection between resolution, photo size – A24

Last time around I left you with information on printer resolutions and camera resolutions.   My Canon iPF 8000, that can print 42 inch wide by 50 feet if I like has a maximum 1200 dpi resolution (higher with interpolation), and my pocket camera, the Canon S60 has a maximum resolution of 2592 X 1944.

When printing I always use the optimum output resolution and I can’t find a reason in my world, no matter what printer I might own, to ever use anything but its best capabilities.  The same holds true when using my camera.  I can on occasion switch from RAW to jpg, but always remain with the best resolution.

You might imagine I take a lot of photographs.  On any portrait assignment I may take a hundred or more images, with variations in lighting and positions.  Out of those I am really interested in only one, the best image.

The same principle applies to all photography.  You might be sailing by the island of St. Barts and have the opportunity to take several dozen photographs of a beautiful beach cove.  You might file them all for save keeping, but for showing and printing you will edit it down to a couple that for some reason, be it for composition, the shadows, or for some visual element.

You have to edit, severely edit your work, or face infinite boredom in showing your photography.  I recently received an internet photo album from a casual friend of his trans-Atlantic crossing, with a message that he considered many were prize winning.  There were over four hundred.  The pictorial story could have been told with a dozen shots, and I can’t say any would win a prize.

Editing can be difficult, especially so if it is your own work, but it is very necessary.  Doing so has its rewards.  The process will help you develop and explore your visual skills and refine your techniques on your next photo shoot.

I would be interested in reader response to the software they are using to make photo editing easier.  I’m not talking retouching or enhancement, but simply noting what are the keepers or best images from those that can be deleted.  Picasso is free software I will be talking about, but frankly at this writing I’m not aware of this editing capability.  I have been using Adobe Library lately and it is particularly adept for enhancements, nevertheless fantastic in selecting and retouching your photographs.  Therefore this software will be included next when covering the subject in greater detail.

Let’s get back to resolutions, printing, and any reason you may want to use less than the highest capable camera resolution.  I’ve noted my highest Canon S60 resolution as 2592 X 1944.  Other, lesser, resolution settings available to me with this camera are 1600 X 1200, 1024 X 768, and 640 X480 ppi.

The latter setting is ideal for any photography you only want to use for an e-mail or on your web site.  If you are going to prepare a larger file, such as a 2592 X 1944 you will be fine with an output resolution of 72dpi.  This will not be suitable for making prints.

Prints require, whether it is for fine printing in a magazine or quality paper prints, require an output resolution of 300 dpi.  This can vary with different printers.  I’ve bee informed by Canon that my iPF 8000 optimum is 240 dpi, so my 300 dpi settings are overkill.  It is also suggested that larger prints, which theoretically are viewed from a greater distance, can also be printed with lower output resolutions.  The key word I used is theoretically, because in my experience in my photo gallery, people do get up close and personal with fine art images.

Keeping with an output resolution of 300dpi for quality printing gives us the means to calculate prints sizes that are possible for your camera at a specific camera resolution.  If you divide my S60 highest resolution of 2594 by 300 it equals approximately 8.5 and 1944 by 300 comes to about 6.5.  This means the ideal enlargement size is 8.5 X 6.5 inches (or less).  The 1600 X 1200 resolution get me a quality 5 X 4 inch print, and the 1024 X 764 makes you a 3.5 X 2.5 inch print.

Early on I noted that other factors add to overall quality photographs, such as lens optics and the size of the image sensor (apart from the total number of pixels on a sensor).  I mention this again not to incorrectly think a 10 megabyte sensor is always better than an 8 megabyte sensor.  I continue to keep my Canon S60 because I like to rare compact RAW capability and the 28mm wide angle capability.

I can’t seek permission to go ashore without letting you know that there is some impressive enlargement software available to blow up any photograph a 1000% or more.  One is called Blow Up, another is Genuine Fractals, and PhotoShop does a great job.  Until next time, wishing you happy visions in the New Year.