GF1 zone focusing?

[Mattikk]

Hello!

I bought the GF1 + 20/1.7 kit couple of days ago and got the voigtländer viewfinder for it too. I am very satisfied with the camera, but there is one thing that bothers me.

There is no meter for the manual focus in camera (like on DP1) or the lens. How can I zone focus without having any idea where the focus is at?

Oh and here's a photo I took today.

 

[Finder]

Set the camera to manual focus and then use the monitor to focus on an object at a distance you want to shoot at.

It seems a little awkward, but it gets easier. I have done this with the 17mm. However, I did buy a cv 21mm lens instead of the Panasonic 20mm because it is easier to zone focus.

 

[jsrockit]

Finder, that negates the advantage of zone focusing.

 

[Finder]

Finder, that negates the advantage of zone focusing.

Yes and no

I want to set the lens to two meters.

I focus on something two meters away.

I start taking pictures.

It is a bit of a pain and there is no DoF scale. But that is the way the camera/lens combo works. Which is why I have a cv 21mm lens on my camera and not the Panasonic 20mm lens.

 

[bwidjaja]

Finder, does the DoF scale on the CV 21mm apply when using it with GF1? Or do you have to do some calculation? Thank you, Berhen.

 

[Finder]

Berhen, you need to compensate two stops. The f/4 marks are for f/8, the f/5.6 marks are for f/11, and so on...

 

[zeezea]

Now I`m really confused

Now I`m really confused

Berhen, you need to compensate two stops. The f/4 marks are for f/8, the f/5.6 marks are for f/11, and so on...

Maybe you can explain something for me. I always thought that the DOF would remain constant for a given lens (assuming same focus distance and f-stop) regardless if mounted on full 35mm frame or mu4/3. For example, if a 50mm lens is mounted both on a FF and mu4/3 set at 6 ft. and f2, the DOF if front and behind the subject would be the same. Naturally the FOV (and subject size on sensor) on the mu4/3 would appear as a 100mm on FF. The big difference of course would be the DOF is still that of a 50mm at 6ft and f2 and not a 100mm needed on a FF to get the same subject size.

Now I have a headache and I`m even more confused. :bang:

Regards,
Al

 

[Finder]

I always thought that the DOF would remain constant for a given lens

Because the m4/3 image is magnified more to reach a similar display size, the size of the permissible circle of confusion is also magnified. So what was acceptably sharp in the 35mm image is a little softer in the m4/3 image.

Try this in photoshop. Display an entire frame filling your screen and visually judge where foreground and background objects start softening--where the limits of the DoF are. Then crop the center portion of the frame and enlarge it to fill the screen. Do the DoF limits that you saw change?

Non-m4/3 lenses get a bad wrap on m4/3 cameras. I believe one reason is folks don't always understand the DoF is also changing.

 

[Finder]

Now, if I could put f/2.8 and f/2 depth of field scales on my lens...

 

[zeezea]

Thanks Finder. 😀

Regards,
Al

 

[zeezea]

Now, if I could put f/2.8 and f/2 depth of field scales on my lens...

Ha ha ha.

Thanks again - it makes more sense to me now. 😱

Regards,
Al

 

[Mattikk]

I wish panasonic could add the focus scale with a firmware update.

 

[bwidjaja]

Finder, thanks. So let me just make sure I get this one. This means if I compare 21mm @ f8 on 35mm film camera vs m4/3; I am getting "half" (less) the depth of field on the m4.3 relatively speaking based on f-stop?

 

[Paul T.]

I think you're confusing him... with the CV 21mm lens on the 4/3, you will have effectively have a shallower depth of field than with the 21mm on a 35mm camera, more or less as he stated.

 

[bwidjaja]

Paul, thanks, I think I got it.

 

[Finder]

Finder, thanks. So let me just make sure I get this one. This means if I compare 21mm @ f8 on 35mm film camera vs m4/3; I am getting "half" (less) the depth of field on the m4.3 relatively speaking based on f-stop?

Right. You would use the f/4 depth of field scales on the lens.