SCOOTING BY

[FUJI]

I was very pleased with myself this afternoon....

I was determined to suss out acquiring accurate Hyperfocal Distance when using a Vintage all manual lens.....

The formulae given for my SUPER TAKUMAR 1:2-55 is f16 says everything from circa 7ft to infinity is in focus....it didn't work.

So after little fiddling and faffing I sorted it out as f8 for this particular lens.....that is about half, so I'm guessing that the calculation is dependent on sensor size?

Numbers have always mystified and befuddled me. ;-))

FUJI

[Guest]

OK so that cost me an hour of my life, I just had to write an article about this for my blog but now I'll share it with you. Any feedback welcome and will if appropriate (and polite) be included in the finished article.

The hyperfocal distance depends on three things:

• the focal length of the lens 
• the aperture used 
• the diameter of the circle of confusion (what is considered to be acceptably sharp.)

I have seen the hyperfocal distance authoritatively described as the distance between a camera lens and the closest object which is in focus when the lens is focused at infinity. This is not helpful and differs from the best interpretation being; it is a distance beyond which all objects can be brought into an "acceptable" focus or to put it another way;

• the hyperfocal distance is the closest distance at which a lens can be focused while keeping objects at infinity acceptably sharp.

The nature of the beast is that the longer the focal length of the lens the less depth of field you will have so hyperfocal distance is useful with wide angle to standard lenses - say 50mm upper limit but for telephoto lenses forget it, concentrate on getting the subject sharp and use the widest aperture you can to get the best quality bokeh. Bokeh? Yes sound like another article may be needed but for now back to hyperfocal distance.

Now one key element in this is the focal length of the lens which in the days of the standard formats of 35mm 6x6 etc. was simple enough but what about the digital era where we see lenses described as X (35mm equivalent Y?) Well it is the native value, the “X” that is needed to do get the correct result NOT the 35mm equivalent and it is her that sensor size comes into play as well.

So now we have it, we know the correct focal length of our lens, we can find a figure for the “Circle of confusion” we can input the aperture and calculate the hyperfocal distance we need to use using the formula H=f2/Nc. Not good at mental arithmetic you say, no problem you can download an app to your smartphone to make calculation in the field easier. WTF I hear you scream, photography is supposed to be spontaneous, I don’t have time for this nonsense.

The I suggest you go online now to a site like http://www.outsight.com/hyperfocal.html pop in the figures for your favourite lens and remember it, or write it on a bit of card to put in your bag in case, like I have done.

Full frame camera, 35mm lens at f11? Focus on 12 feet and you are good to go from 6 feet to infinity. Just set the camera to manual focus and auto iso and forget! Go take great photos.

I like the mono version best Fuji, nice one!

[FUJI]

Hi, Bill,

A huge thank you for your very helpful input regarding Hyperfocal distance for a vintage lens....

You are right ......I attempt to understand your formulae, and immediately reach my personal....Circles of Confusion.......this is my problem, any and every smidgeon of mental arithmetic, scales and calculations, send me into a spin.......So bad is it, that I rarely proffer the correct change when making purchases, No matter how hard I try, I end up getting it wrong.......I have ...Discalcluia .....the number version of Dyxlexia ......Yet for 25 plus years I was a joiner.....my measuring and cutting hardly faltered......I'm ok, as long as I calculate I'm my own way, in my own time.....I used to drive my teachers to distraction.

Right!.....back to this......I will look up that app, and then use it as you suggest, if I can.

One area of confusion, is that here I used an M 4/3 camera with a Vintage 1:2-55 film camera lens, so old tech with a smaller sensor, so this must alter the standard figurers I had carefully written down......also making the scales on the lens unusable?

My solution was to go to f8 then ensure focus at a minimum of around 8 feet......I noticed I had good focus a good deal further back too.

Why do I punish myself and not stay fully Auto?.......because I enjoy a challenge.

I am guessing that many of you would have a similar block, if I asked you to paint a water-colour portrait of a Snow Leopard.......I don't know how I do it but I just do...

A funny old world?

FUJI