Hi,

First thanks you very much for all you advices, I really appreciate ! I think the film loading is not a big deal, after 3 days (!) it seems ok now, not as fast as I usually do with a classic SLR for example, but it's fine to me..

Now I'm just looking on the web for a good tutorials about the hyper focal technique :-)

Thanks you again !

Simon (A really happy new user:-)

-- Simon (s_alibert@mac.com), June 07, 2002

Answers

Film loading for me is just as easy with an SLR. Just make sure the sprockets and neg engage properly and the film leader is within the 3 prongy bits in the take up spook and thats just about it. Hyperthetical focus is easy, though I only use it for lenses 35mm and less as the depth of field is much greater for wide angles (if you look at the various leica lenses, DOF scales on the lenses are futher apart the wider you get.
An example of how you can use this it to set the aperture to lets say F16, Focus the infinity part of the lens to the F16 DOF mark and then if you look at the F16 mark on both sides of the scale, you will be able to see the range in meters that will be in focus. For a 15mm lens this will prob be from 30cms to infinity.
This technique is very useful for those fly by pictures. Hope that makes sense!
Another thing that helps if if you learn which way to turn to lens for far objects and which way to turn it for nearer objects, and actually start focussing before you bring the camera to your eye.
These are the quirks of M photography!!! ENJOY

-- Karl Yik (karl.yik@dk.com), June 07, 2002.

Simon, You can calculate the hyperfocal distances for any lens using the following calculator www.frii.com/~mbaltuch/Hyperfocal.html

I drew up a chart (on MS Excel) for the 40mm lens on my Rollei 35SE miniaturised it and had it laminated. It's smaller than half a buisness card, tough and waterproof to boot! Cheers,

-- Tim Gee (twg@optushome.com.au), June 07, 2002.

For a 35mm lens (all I use as I have a Hexar AF)

Hyperfocal distance (in meters) = 40/aperture.

So if you were using a fstop of 8

Hyperfocal distance = 40/8 = 5 meters.

I believe you use 50 as the constant for a 50mm lens though maybe wrong.

The above calculation is just an estimation but is fairly good. Remember to focus at the distance calculated. Then everything from half the hyperfocal distance to infinity will be 'acceptably in focus'.

Hyperfocal isn't to bad to understand its Merklingers infinty technique that I can't quite understand.

Also trying to get to use zone focussing without good depth of field markings on the Hexar AF.

Good shooting.

-- bubble (bubblegrass@yahoo.com), June 07, 2002.

Don't forget that DoF is an optical illusion, caused by our less-than- perfect vision: we cannot detect unsharpness until the "circles of confusion" become large enough for us to see. DoF is calculated assuming a enlargement magnification of 4 times; if you enlarge more than that, you may start to see unsharpness at the front and rear of the so-called "DoF".

I must admit, I'm a bit conservative when it comes to DoF and the hyperfocal setting: I tend to base it on a wider aperture than I'm actually going to use. For instance, if I intend using an aperture of f/11, I'll base the DoF on f/8.

-- Ray Moth (ray_moth@yahoo.com), June 07, 2002.

Martin [Tai], we need you!!

:-)

-- Dexter Legaspi (dalegaspi@hotmail.com), June 07, 2002.

The formula for finding hyperfocal is:

K=ma, where K=constant, m=hyperfocal distance in meters, a=aperture

For 28mm I use K=35; 35mm K=50 and 50mm K=100. Those values give me one stop *tighter* tolerance than the DOF scales on the lenses. If you wanted the same DOF scale as the lens, you would multiply the constants by 1.5: 28mm=50 (rounded off); 35mm=75, and 50mm=150.

To use the formula, you can use K/a=m to find the hyperfocal distance for each aperture, or K/m=a to find the aperture you need for various distances. This latter one is the one I use most. Since hyperfocal is defined as everything being in apparent sharp focus from *half* the hyperfocal distance to infinity, I focus on my nearest object, double the distance, and plug that into the K/m=a formula to find what aperture I need to get that nearest object in focus.

I used this with my Tri-Elmar (since it has no DOF scales and the ones on the new version I find too confusing for quick use)until I happened on a better solution: I found an old pocket sliderule and transferred the DOF scales from 28, 35 and 50mm lenses to it.

-- Jay (infinitydt@aol.com), June 07, 2002.

I always thought the HFD can be had just by looking at the lens? and moving it? Why do you need to calculate them?

-- Lux (leica@sumicron.com), June 07, 2002.

Lux,

Some lenses don't have dof markings or they are difficult to interpret on some lenese.

Jay,

Could you expand a little on your second method. My brains a bit fried after watching all the football this morning.

Thanks,

-- bubble (bubblegrass@yahoo.com), June 07, 2002.

But I think for Simons case (who after all asked the question), he would have some of the latest lenses, plus what all this formula stuff... Its like getting into astro-physics! We're not supposed to scare him off you know! Lets keep it simple!

-- Karl Yik (karl.yik@dk.com), June 07, 2002.

The Hyperfocal distances are not the same thing as the DOF markings on the lens. The HFD is the focus point, such that anything between half the distance to the focus point and infinity is in focus. eg. If the HFD is 6 feet, then if you focus at 6 feet, everything between 3 feet and infinity is in focus. Using hyperfocals is the way to maximise the DOF and enables you to take fast candid shots for example with the focus pre set. This is a good way to get lots of stuff in focus with a Rollei 35 which doesnt have a rangefinder.

I use it all the time and I'm not particularly cleaver. See my contribution above to get the info and a handy calculator.

-- Tim Gee (twg@optushome.com.au), June 07, 2002.