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Thread: Why doesn't G1 give manual focus distance info?

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    Why doesn't G1 give manual focus distance info?

    Well, I've asked Panasonic, and couldn't get through to anyone who understood my question. So, I thought I'd consult the experts (you) .

    Does anyone know why the DMC-G1 doesn't display the focus distance when you're manually focusing? This would be imminently helpful in using hyperfocal distance to zone focus.

    If any of you have a Lumix DMC-LX2, you will have seen that it actually displays a distance scale, highlighting the range of distances currently in focus. This is super-helpful in zone focusing.

    I know that the focus-by-wire lenses on the G1 are different from most other lenses, but does that mean that the camera really doesn't know what distance it's focused at? I suppose that's possible, but certainly not good for those of us who want to use the 20mm f1.7 for street shooting, for example.

    I appreciate your insight(s).

    Regards,
    Reed

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    Re: Why doesn't G1 give manual focus distance info?

    I can only speculate as I have no real info, but here are two data points:

    1. It isn't necessary for either a contrast detect AF system (like in the G1) or a phase detect AF system to actually know the focus distance in order to focus. Only relative movements from "where it is now" are necessary.

    2. Canon's RAW converter (DPP) can apply lens corrections, some of which are dependent on focus distance. With newer bodies and lenses that information comes through in the RAW meta-data, other lenses and bodies it doesn't. I believe Canon actually added this info for its flash system (so the flash would know what the photographer actually focused on to better expose at that distance) but they are using the information to help their lens corrections.

    Put these together and there is no reason Panasonic strictly needs to know absolute focus but you'd think it would help with their corrections. If they do know it then it really is mystifying why they wouldn't allow it to be displayed somehow! My LX3 shows this info...

    Ken

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    Re: Why doesn't G1 give manual focus distance info?

    Quote Originally Posted by rgeorge911 View Post
    I know that the focus-by-wire lenses on the G1 are different from most other lenses, but does that mean that the camera really doesn't know what distance it's focused at? I suppose that's possible, but certainly not good for those of us who want to use the 20mm f1.7 for street shooting, for example.
    Reed, The 20/1.7 has no or limited use for street photography for me.
    I look at it as a special purpose lens that fits the vision of Pana.

    What would be more useful for me than distance scales displayed is if the lens would let me focus (either manually or in AFs mode) at all without any hesitation.

    This is what I would like to see in any prime lenses:

    1. a real aperture that can be set manually.

    2. a real manual focus possibility that does not need any electricity.

    I think I would be using this lens reversed as a macro lens more.

    Does a splendid job this way!

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    Re: Why doesn't G1 give manual focus distance info?

    Focus by wire will not show focus distance. It is my only beef with the Pen 1 and now the G1. The 17mm lends itself to street work better than the 20 due to it's greater FOV and thus DOF.
    I use the Pen with Hyper Focal alot but because of the lack of a focus scale, less and less every day. The cameras work well on the street but you have to adjust your way of thinking.
    Shooter

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    Re: Why doesn't G1 give manual focus distance info?

    It is not just the flimsiness in appearance and handling but the Oly-D 17/2.8 actually does move and move it does without much protest. First plus point.

    It is not just the slow aperture but all the optical flaws it has (field flatness, distortions) actually help the final image. Second plus point.

    It is not the lack of sharpness that is the problem. That is also a boon.
    While on tripod with a cable release, etc, or on an optical bench, the Oly-D 17/2.8 may not be the lens worth fondling, but in real life (hand held), it delivers better captures.

    Lastly, for me, with a GW-1, it actually focuses faster.

    The 20/1.7 is a special purpose lens.

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    Re: Why doesn't G1 give manual focus distance info?

    Vivek,
    I just ordered the 20mm and will have it tomorrow.
    I did a few shoots this last weekend with the Pen, G1, 14-45 and the 17mm.
    I used flash which is how I test every camera/lens.
    With a Nikon SB22a, the 17 is startling....
    I will test the 20mm this week.
    I only need it for the 1.7 aperture.
    Don

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    Re: Why doesn't G1 give manual focus distance info?

    Hmm. I really didn't intend for this to become another critique of the 20mm lens, or comparison to the Oly lens.

    If I could set the manual focus at the hyperfocal point, this lens would be very useful for my style of street photography. The argument that the 17 is better because of the wider fov and dof is a matter of pure opinion. I believe that a lot of nice street work has been done at 50mm in 35mm film format, no?

    I do still wonder if the camera knows the point of focus of the lens. I suspect that it does, but can't say for sure. If it does, it sure would be nice to see it on a display somewhere.

    Reed

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    Re: Why doesn't G1 give manual focus distance info?

    Reed,
    There's no argument. All posters are streetshooters.
    The 17mm is my natural FOV. I could use a different lens but I see 35mm naturally.
    The DOF is a concern between these 2 lenses.
    Like you, I suspect the cameras know the focused distance but they ain't talkin'.

    I've had to change my method of operation due to the lack of a focus scal but sometimes a change is a good thing.
    Are you using the finder? Do you know where to get the HD tables?
    Shooter

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    Re: Why doesn't G1 give manual focus distance info?

    Hi Streetshooter,

    Thanks for your reply. I agree that the 35 or 50mm choice is just that for street shooting, a choice. Thanks for your thoughts on it.

    I do have the HF points for all of the f-stops for this lens. The only way I know to use them is to focus on something approximately that far away, and not touch the focus again.

    I'm using a Russian VF, which strangely is a little narrower than what actually shows up in the picture with the 20mm on the G1. But, it's very close.

    Regards,
    Reed

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    Re: Why doesn't G1 give manual focus distance info?

    Quote Originally Posted by rgeorge911 View Post
    The argument that the 17 is better because of the wider fov and dof is a matter of pure opinion. I believe that a lot of nice street work has been done at 50mm in 35mm film format, no?
    Not my argument (FL or DOF).

    The 20/1.7 sucks for street photography in my use.

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    Re: Why doesn't G1 give manual focus distance info?

    Alright, I'm done with this conversation.

    Thanks, Streetshooter and others for discussing the topic I started with.

    Reed

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    Re: Why doesn't G1 give manual focus distance info?

    Wait, wait! We haven't found out what Vivek thinks of the 20/1.7 yet!

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    re: Why doesn't G1 give manual focus distance info?

    returning to the original question:

    Quote Originally Posted by rgeorge911 View Post
    ... Does anyone know why the DMC-G1 doesn't display the focus distance when you're manually focusing? This would be imminently helpful in using hyperfocal distance to zone focus. ...
    I don't think anyone outside of Panasonic's engineering department can tell you the true why of it. And getting access to the right engineer there would be next to impossible.

    They don't encode it into the EXIF data either. Whether they even use it internally or not is a question mark ... there's functionally no need for distance information, given the way the cameras' CDAF focusing and TTL ambient/flash light metering operate.

    I can only conjecture that since they have no functional need for distance information, they simply omitted calibrating the camera/lens assembly to report it. I suspect the engineering crew simply had enough other stuff on their minds... But it's only a conjecture.

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    Re: Why doesn't G1 give manual focus distance info?

    Godfrey,
    By Jove, I think your right.....

    (Easy on Vivek please.......We're all street shooters and the way we learn our new tools is by teaching each other.....I've gotten much good info from Vivek and others and I value all their opinions....)
    Shooter...out

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    Re: Why doesn't G1 give manual focus distance info?

    Don,

    There is a serious mechanical flaw with the 20/1.7 focus mechanism. It has nothing to do with the weight of the lens unit as reasoned by some.

    Pana would benefit by examining the 17/2.8 and the 20/1.7 side by side to correct it if they care and come up with a Mk II version of this lens.

    As for the others and their thoughts, I couldn't care less.

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