4/3 Users - How Good is Selective Focus DOF control on 4/3 Cameras?

NickTrop

NickTrop

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Looking at some of these cameras... Ability to blur background is a must. Sample photos much appreciated. Thanks in advance.
 
Sorry, no examples. But according to the DoF calculator, the depth of field is the same as a 35mm film camera set to two more f-stops.

E.g, the DoF of a 4/3 camera at f/2 would be the same as a film camera at f/4.
 
antiquark said:
Sorry, no examples. But according to the DoF calculator, the depth of field is the same as a 35mm film camera set to two more f-stops.

E.g, the DoF of a 4/3 camera at f/2 would be the same as a film camera at f/4.
Click to expand...

Thanks a lot, antiquark... Man, I'm tempted - but that's a lot of f stops to give up! So, f2.8 - like the prime on that soon to be released Oly, is f5.6 in terms of DoF, essentially none (or all I should say) shooting wide open. Might was well be using a digital point and shoot in this regard. :(
 
Would love to see some shots with the EP1 or EP2 and the 17mm lens at or near wide open and set to like 6 to 10 feet. Just wondering how it would work for street shooting where I want some flexibility but still want a little isolation.
 
Images speak louder than words:

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Taken with a variety of lenses and either E-1 or E-520 bodies. Go to my Flickr stream and search using the keyword "Olympus" to see more examples.

Regards,

Bill
 
My calculation was like so. I used equivalent FoVs for both cameras, which means 25mm on a 4/3, and 50mm on a film camera.

So, according to the calculator:

Sensor = 4/3
FL = 25mm
Distance = 10 ft
Aperture = 2.8
DoF = 4.28 ft

Sensor = 35mm film
FL = 50mm
Distance = 10 ft
Aperture = 5.6
DoF = 4.25 ft

I think it's usually more informative if you compare based on field of view. It makes more sense too, if you're dealing with digi point and shoots that have extremely small FL's, like 4 mm. There's no such thing as a 4mm lens for a film camera, yet the 4mm lens on digital might have an equivalent field of view to, say, a 28mm lens.
 
Getting a good sense, glad I posted this thread. Deciding between the soon to be released Oly with the audio attachment (want the camera to do some video work...) or the Samsung NX10, which has the same larger sensor as the Pentax K7. Selective focus, however, is a must. Was skeptical of the 4/3 cameras in this regard due to their sensor size. Thank you, all! Much obliged.
 
I use two Four Thirds cameras. Out of focus backgrounds are much more difficult to get than on a full frame 35mm camera. While the field of view of my Zuiko Digital 25/2.8 is that of a 50mm lens on my M3, its focal length is half that, so depth of field is that of a very wide angle lens rather than that of a normal lens.
 
If you want to have 35mm-like DOF on 4/3, couldn't you just get an adapter and use legacy 35mm lenses on the 4/3 body? Cropping does not change the DOF, does it? DOF is a property of the lense, not the sensor.
 
NDAv said:
If you want to have 35mm-like DOF on 4/3, couldn't you just get an adapter and use legacy 35mm lenses on the 4/3 body? Cropping does not change the DOF, does it? DOF is a property of the lense, not the sensor.
Click to expand...

DoF calculations assume that you print your picture at an 8x10 size (IIRC) without cropping.

DoF is a nonlinear property of focal length, sensor size, aperture, and print size. So it's usually a good idea to let a calculator do the thinking for you :) : http://www.dofmaster.com/dofjs.html
 
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The Sigma 30/1.4 is expensive and bulky, as is the Leica 25/1.4. The Canon 50/1.2 would give an effective focal length of 100mm. On a full frame 35mm camera, even the "too slow" f/2.8 on a 50mm lens offers a degree of control over depth of field. I said, "Out of focus backgrounds are much more difficult to get than on a full frame 35mm camera." I do not retract that.
 
The sigma 30mm 1.4 is a bargain in comparison to other fast lenses. I know I could get one for olympus 4/3s mount for about $500 Australian which is like 420us. It's a really good lens too. Not too big either - about the right size for a fast prime for DSLR and a whole lot smaller than my 35mm 1.4L
 
I have a small wallet, Gavin, so I must make do with the 25/2.8. If I raise ISO to 800 from the usual 200, I get the same exposure times as I would get with an f/1.4 lens "normally". The greater depth of field cannot be helped: but with careful positioning its effect can be minimised.

NickTrop, for selective focus on a Four Thirds camera you will need large apertures or long focal lengths or both. Life itself is a compromise.
 
payasam said:
..for selective focus on a Four Thirds camera you will need large apertures or long focal lengths or both. Life itself is a compromise.
Click to expand...

...as is true for any camera. It is only the degree that changes. The OP's question was whether it was possible to blur background with a 4/3 - the answer is yes.

Personally I don't stand there calculating it, I just do it.

Regards,

Bill
 
NDAv said:
If you want to have 35mm-like DOF on 4/3, couldn't you just get an adapter and use legacy 35mm lenses on the 4/3 body? Cropping does not change the DOF, does it? DOF is a property of the lense, not the sensor.
Click to expand...

Simply adapting a 35mm FF lens to 4/3 won't magically give you less DOF.

The trick to shallow DOF on smaller formats is to use wider f/stops. If you want the DOF of a 50mm lens at f/4 on 35mmFF you would need to use a 25mm lens (to match FOV) at f/1.4-2.0 on 4/3.

The reason adapting legacy lenses is a common path toward shallow DOF is only due to the fact that very fast short teles can be had by adapting fast 35-85mm lenses. Lenses with speeds not generally available in native 4/3 lenses, particularily when dealing with m4/3.
 
Basically, you'll get shallow depth of field on up close objects and not much else... better than small sensor P&S cameras, but not like 35mm film.
 
The 4/3 system do deliver fairly good shallow dof with fast lenses, almost on par with the M8 or any other crop sensor dSLR, the 4/3 will have slightly less shallow dof on the same fov compared to a crop sensor SLR.

remember the 4/3 is a 2x crop
dslr varies from 1.3 to 1.5 ish


Bo

www.bophoto.typepad.com
 
This was taken with an e-520 and 50mm @ 1.4. Given that the dogs head is about the size of a child's head shows that 4/3 is capable of taking portraits with blurry backgrounds.
It's definitely easier with a full frame though. That's the primary reason I've gone back to film camera's... besides the cost of FF DSLR's.

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jsrockit said:
Basically, you'll get shallow depth of field on up close objects and not much else... better than small sensor P&S cameras, but not like 35mm film.
Click to expand...

*Shakes head* Nobody listen to Zathras...

Does this look like an "up close object"...?

3618356150_61704561d9.jpg


Regards,

Bill
 
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