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back alley
18th January 2009, 15:25
are the settings for hyper focal distance shooting the same if i use a lens on a film body and the g1?

i went out today in the blazing sunshine, zm 21 on the g1 and set the aperture at f8 and then set the lens distance for hyper focal shooting.
shots were sharp so it must have worked but i still feel the need to ask.

joe

Vivek
18th January 2009, 15:37
Joe, The liveview (big screen and not the EVF) actuall would show you what difference it makes if you check the lens wide open to say, f/8. This isn't a range finder camera, you know (just stating the obvious in case you forgot)!:)

back alley
18th January 2009, 15:40
agreed, but it's the closest thing to a drf than i can afford ;)

Bob
18th January 2009, 16:32
Not such a dumb question.
A lens actually focuses at only one distance. In front of and behind that point of focus, the image blurs. The amount of acceptable blur for something to appear in-focus is called the circle of confusion. It actually varies depending on film and sensor size, and some say, for critical nose-distance viewing (including me) by the pixel pitch of your sensor.
For a print-size DOF explanation see http://www.bobatkins.com/photography/technical/dofcalc.html
From my point of view, however, the DOF scales seem always to be too generous since I am a dyed-in-the-wool pixel peeper LOL
-bob

Terry
18th January 2009, 16:39
Not such a dumb question.
A lens actually focuses at only one distance. In front of and behind that point of focus, the image blurs. The amount of acceptable blur for something to appear in-focus is called the circle of confusion. It actually varies depending on film and sensor size, and some say, for critical nose-distance viewing (including me) by the pixel pitch of your sensor.
For a print-size DOF explanation see http://www.bobatkins.com/photography/technical/dofcalc.html
From my point of view, however, the DOF scales seem always to be too generous since I am a dyed-in-the-wool pixel peeper LOL
-bob

Bob, following on to the sensor size part for the M8 wasn't the best advice to use a stop or two less on the scale? For instance if you were shooting at f8 use the hyperfocal setting for f5.6.

petermcwerner
19th January 2009, 00:01
Bob, following on to the sensor size part for the M8 wasn't the best advice to use a stop or two less on the scale? For instance if you were shooting at f8 use the hyperfocal setting for f5.6.
So shouldn't it be more stops for the G1 since the sensor is smaller than on the M8? Is anyone bold enough to make some tests to see whether the theory is correct in real life?

Per Ofverbeck
19th January 2009, 00:50
A major problem is that one canīt trust the distance scales when using adapters. My Novoflex (for Leica M lenses on G1) is a bit too thin, so when focussing any of my lenss visually on a distant object, the scale says something else (depends on the FL of the lens, since it is a fixed flange distance error); on my Summicron 50 it is between 5 and 10 meters. And, yes, all the lenses focus correctly on my M2.

ecliffordsmith
19th January 2009, 03:39
Hi All,

As Terry stated, use the hyperfocal distance one stop above your actual aperture.

Bob
19th January 2009, 03:41
According to my calculations, a 4/3 camera when stopped down to f/16 should yeild the same dof as a 35mm camera at f/8.
So roughly speaking, you can use the lens scales with a two stop offset.
-bob

ecliffordsmith
19th January 2009, 04:07
Bob,

Good point! I was in M8 land when I was reading this thread!

Terry
19th January 2009, 04:16
According to my calculations, a 4/3 camera when stopped down to f/16 should yeild the same dof as a 35mm camera at f/8.
So roughly speaking, you can use the lens scales with a two stop offset.
-bob

Bob, isn't it reversed that the 4/3 at f8 = 35mm at f16?

Vivek
19th January 2009, 06:28
Distance scales, hyperfocal.. come on folks, this isn't a range finder and it isn't a TLR or an SLR with mirror lock-up.

back alley
19th January 2009, 07:57
Distance scales, hyperfocal.. come on folks, this isn't a range finder and it isn't a TLR or an SLR with mirror lock-up.

what does that matter?

scho
19th January 2009, 07:58
Distance scales, hyperfocal.. come on folks, this isn't a range finder and it isn't a TLR or an SLR with mirror lock-up.

Ahh..,but it brings back fond memories of my old Rolleiflex when I'm shooting the G1 at waist level. Now if only we could have a Gx with a square sensor:)

Vivek
19th January 2009, 08:03
Carl, I still have a Topcoflex (the bigger bro of Primo Jr, I have one of those beauties as well)! :)

peterv
19th January 2009, 11:44
Bob, isn't it reversed that the 4/3 at f8 = 35mm at f16?

I think so too, Terry.

The COC for 4/3 is half the size of 35mm, so called full frame. So that alone will double your DOF zone.

DOF is for me, after 30 years of dealing with it, still a confusing item :cry:

Here's another interesting and helpful link:

http://www.dofmaster.com/dofjs.html

Cheers, Peter

Robert Campbell
19th January 2009, 12:32
There's a useful dof calculator here:

http://www.cambridgeincolour.com/tutorials/DOF-calculator.htm

psurfer
20th January 2009, 22:36
I was thinking about this, too . That hyperfocal dist settings would be very useful for pre-focusing. (Still have no lens adapters yet, and still thinking MF in most low light situations handheld is going to be a major PITA w/this camera...)

Y.B.Hudson III
20th January 2009, 23:50
sheeze... when focusing wif t' G1 & NoctiLux, I have to put on my sungLasses in lowlight [email protected] 2.8's acceptable, 2.0's gooD, 1.4's exceLLent...the diopter correction is eXcellent for the aging demographic...a diopter correction and magnifier for a Leica M costs aLmost as much as the G1 and is a dim set-up...