Poke A Key – Steer A Mouse – Tap A Screen

Poke A Key – Steer A Mouse – Tap A Screen

Photographers who may find themselves confined to their home for some time due to various reasons – illness, financial straits, or a court order, for instance – can still have a lot of fun and learn many new facts by resorting to their computer and the resources of the internet. We’ll leave aside the visual temptations of Icker, Monstagram, or any of the other purely presentational sites and direct you to technical ones. I mean, beautiful images are all very well for the professionals, but when you come right down to it, the amateur photographer wants specifications and technical comparisons, eh?

So today’s site is Dofmaster. Go to dofmaster.com and look at the variety of products you can get for your information devices. They do a number of electronic programs for the different forms of mobile phone or tablet and for the fixed computers. You can pop right into the depth of field calculator and experiment with the idea before you commit to anything. I use the free bit all the time to compare and contrast different lenses.

The idea is you dial in…( dial?…who remembers dialling radios and telephones…oh dear me…) your focal length, your camera, your aperture, and the distance to your subject. The Dofmaster then tells you how much depth of field you’ll have for an average circle of confusion resolution and where it will be situated – before or behind the subject.

If you need to know this or to select some criterion to either maximise or minimise it, you have it all there before you actually have to set up for the shot.

In many cases it has provided me with reassurance that I could, indeed, encompass a subject I wanted to shoot – but in others it has warned me off from trying to do the impossible. For the shooters who venture off the tabletop and out of the studio, the field of depth can become a lot easier – they have more distance to play with and fewer worries about restriction. That is, until they go slightly mad and try the pleasures of large format photography…

You can see this for yourself if you use the Dofmaster calculator. When you venture up past 150mm focal length – and remember that is a standard lens for the 4″ x 5″ film shooter – you start to lose depth of field rapidly. Get to 240mm or 360mm – not unusual choices for large-format lenses – and the situation becomes even narrower. Your saving grace in some cases is the fact that the shutter makers will let you go to f:45. f:64, or even smaller…if you are willing to deal with diffraction, you can claw back some of that depth of field.

The large format worker is working under a dark cloth for most of their serious composition – and it is a wonderful experience under there – but it can be dim and awkward to see what is truly in focus and what is only wishful thinking. Dofmaster can reassure you when you cannot be actually certain.

Note: for the people using action cameras and tiny compacts…everything is in focus – whether you like it or not.

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