Hyperfocal cheat sheet for medium format?

moomike

moomike

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Hi all,

Does anyone have any idea where I may be able to find a medium format hyperfocal cheat sheet?
I must own up to mainly using the lazy, focus on what I need sharp & then stop down to get everything else in focus method but I'd like to get back into some good habits with film rather than just guessing & hoping.

Also, I've heard it suggested that to take into account the increase in size of medium format over 35mm, you can focus using the scale at a given aperture & then step it down eg. Use f/11 to read your hyperfocal distance on the distance scale & then shift aperture to f/16 without adjusting focus - is this something recommended by those in the know or have I got that totally wrong?

Cheers in advance for any help or advice.

Mike.
 
hmm lee frost book says roughly

hyperfocal distance = F (squared) / (fxc)

F= focal length in mm

f= apature

c= circle of confusion, 0.036 for 35mm, and 0.127 for medium format

so 90mmf16 = 8100 / 2.032 = 3986

so 4 meters focus distance, and half towards you should be in focus too (2 meters)

someone check my math :p
 
I often use a smartphone app called Photocalc. You can choose any format of camera, enter the distance to subject. Tell it which aperture you wish to use. It'll give you distances in plane of focus, hyper focal distance as well. Pretty useful..
 
OK, I'm a complete dolt and dunnderhead when it comes to this technical stuff but am I right in saying that using the chart in Ash's link then this is true,

on a 6 x 6 camera with an 80mm lens when your point of focus is at 100' then everything from 22' 8" to 1096' will be in focus.

Generally I just pick a point and get that sharp. Simple is what I is.
 
I think it has to depend on the aperture, Andy.
 
yes, well "infinity" at the other end, all should be in focus.

Actually im quite surpised how far away the focus zone gets if you need infinity on a MF camera. On a FF camera you can get it right up close to the lens!
 
Paul-H said:
Is there not a Hyperfocal distance markings already on your lens, just about every medium format camera I have ever owned has had one.

what Camera are you using, Hasselblad, Bronica & Mamiya cameras should have them.

Paul
Click to expand...

Agreed. Many, if not most, medium format cameras and lenses have markings for depth of field. The only medium format camera I've owned without these markings is the Fuji GA645. I just printed a DOF chart onto a small sticker and stuck it on the back of the Fuji to solve that problem.
 
Being lazy, I don't like the calculation method. It depends on being able to accurately focus on a rather specific distance and gives a spurious sense of what will be in focus anyway. Depth of field depends on a number of variable, one of which is the size of the circle of confusion (the biggest size a round dot can grow to in a print and still look like a point) and this depends on how much you're going to enlarge the image. Not to mention how good your eyes are, what the lighting you're viewing the print by is like, how close you're viewing etc. Every time you double the enlargement size, you double the size of the image of an out of focus point, and eventually it won't look like a point anymore and be visually out of focus.

Given that the depth of field markings are calculated using the maker's guess of how big you'll print (and all the other subject variables), I use them but for the aperture one stop smaller than I'll actually be using - as the original poster said. For example, if I'm using f/11, I'll use the f/16 markings as my guide.
 
I still can't work out the distance gauge on the side of the RB67. There is a dof guide on the lens but that isn't coupled to the focus system.
 
steveo_mcg said:
I still can't work out the distance gauge on the side of the RB67. There is a dof guide on the lens but that isn't coupled to the focus system.
Click to expand...

That's exactly what I have mate, it's mainly that I was confused about.

Thanks to everyone for taking the time to reply & help - will have a proper read through & see if I can figure anything out from them :thumbs:
 
moomike said:
I must own up to mainly using the lazy, focus on what I need sharp & then stop down to get everything else in focus method but I'd like to get back into some good habits with film rather than just guessing & hoping.
Click to expand...
IMHO, this is the best way to focus unless you need something in focus that is short of the HFD while also maintaining "infinity."
That's because, no matter how far beyond the HFD you focus, the near edge of DOF will never be farther away than the HFD. And because there is only ever one point that is actually "in focus."

Use f/11 to read your hyperfocal distance on the distance scale & then shift aperture to f/16 without adjusting focus - is this something recommended by those in the know or have I got that totally wrong?
Click to expand...
That's not really to account for 35mm vs MF... it's to account for how the manufacturer determined the DOF scale being used if you feel it is a little to lax.
 
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i think part of the rb67 scale is todo with exposure?

i guess if you have a hyperfocal distance in mind, u could focus the camera on something you think is that distance i guess
 
Yeah part of it is bellows extention exposure compensation.
 
i had a look on mine, doesnt help that theres only a few colours and they are shared between lenses :/
but i think you take the coloured line that likely matches your lens, and then match it to the distance scale
ive not tried it yet, but i think thats how its ment to work
 
The RB67 scale is very pretty tho and the bellows look ace :-)
 
Is the request specifically about the RB67? - if so I should have a DOF/exposure cheat sheet somewhere that I kept as a laminated printout in the bag when out with mine. It may take me a while to find the digital file though, haven't come across it in a while and I've changed PC since then.. ..
 
Alastair said:
Is the request specifically about the RB67? - if so I should have a DOF/exposure cheat sheet somewhere that I kept as a laminated printout in the bag when out with mine. It may take me a while to find the digital file though, haven't come across it in a while and I've changed PC since then.. ..
Click to expand...

That would be amazing if you did manage to find that Alastair, no mad rush though as I'm not getting the camera til Christmas :)

I was checking all of my lenses for the focus scales & checking I actually understood it fully when I read about compensating for the bellows, etc & realised I could use all the help I can get :)

Cheers to everyone that's taken the time to reply :thumbs:
 
That was easier to find than I thought, but whereas I thought the reverse had the hyper-focal distances it actually had a simplified zone system aide memoire for spot-metering..

.. but it did prompt my memory as to where I was getting my depth of field tables from.. http://www.cameramanuals.org/mamiya_pdf/mamiya_rb_lenses.pdf
 
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