GH2 No DOF?

Wow... that's great news about the 17mm .95. I have the 25mm .95 and it's simply the most elegant awesome lens ever. The new one sounds even more promising as it's click less like the hyper prime which I love too.... 1500 bucks though is a pricey lens....
 
Gary Huff said:
Once that 17mm f/0.95 Voigtlander lens is released, I think you'll be seeing a lot more "5D"-like shallow DOF from the GH2.
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Oh, no... tell me it's not true...

For me there would be only one reasons for a f/.95 lens... I need the light... and it would be nice to stop down to 2.8 in 'low light', rather than shooting wide open...
 
Here's a shot with the 14-140 with a moderately shallow DOF. I forget what the settings were, I'll have to look it up when I get home.
 

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MPB said:
i hope you guys read Mr. Foreman's first post, above. he offered a very good explanation. the idea that you want to get as far away from your subject as possible to decrease DOF is a common misconception. DOF increases as your point of focus gets farther from the lens. and as you get further into the telephoto end of a lens, there are even fewer depth cues in your field of view, making the image very flat.
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Admittedly, the OP is not using his terms entirely clearly, but I am going to speak for him and say that what he wants to achieve is his foreground subject well-isolated from a blurred background.

In which case, one of the things Mr Foreman says: "more distance makes background go more out of focus"
 
Backing away from the subject and background is not going to help as such. If we take a lens meant originally for a full size camera and install it on a crop camera, you actually need to back away from the subject to get the same field of view. The increased distance from the subject increases depth of field. Using the same lens one needs to go closer to the subject or be able to open up aperture to get separation between subject and background.

This is the reason why it is assumed that a smaller sensor size increases depth of field. It's not the size of the sensor or the properties of the lens, it's the distance from the subject that has to grow for a smaller sensor. Or the lens has to become shorter in focal length to cover the same FOV.
 
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This is the effect I am referring to (each successive shot is taken from further away, using a GH2).

Walking back.jpg (click on thumbnail to enlarge it)
 
Absolutely, if it is possible to change to a longer lens or zoom in when the distance from the subject and background grows. If you only have one fixed focal length lens, then the options are to open up the iris or get closer to the subject. This is demonstrated in the one close up sample above.
 
GrahamH said:
Admittedly, the OP is not using his terms entirely clearly, but I am going to speak for him and say that what he wants to achieve is his foreground subject well-isolated from a blurred background.

In which case, one of the things Mr Foreman says: "more distance makes background go more out of focus"
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more distance between subject and background. not between camera and subject.

this is easily demonstrated by looking at a dof calculator.
 
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