Episode 058: White is Grey - and Black too!

icon for podpress  Podcast Video (38.2 MB): [28:19m]: Play in Popup | Download (8995)
icon for podpress  Torrent: Download (382)
icon for podpress  The image as XCF file and the script: Download (793)

Finally the “Zone Adjustment Plugin” - formerly known as “Meaningful Black Script” is shown in its full glory. You find it here and in the companion file.

EDIT: This plugin has evolved tremendously. Go to the Forum entry and search from the last postings backwards for it’s latest incarnation!

And I present a plugin for displaying EXIF information in an image, a split toning plugin and a plugin for applying the “Lazlo Dragan effect”. (Download should now be possible without need to register - sorry, made a mistake in the configuration.) All were published in the Forum of Meet the GIMP.

You can find information about the installation of these plugins there too. Basically you just copy them into your plugin directory (not the scripts directory) and make them executable. The last step is not necessary under Windows.

The show starts with a short introduction into the Zone System of Ansel Adams. Before we go deeper into this, we have to calibrate our cameras. Set your camera to manual mode, set the metering to spot or center based and shot a well exposed image of something middle grey or whitish with a bit of structure in it. I took a white door, but raw concrete is fine too. Then shoot two series of images, the first one closing down one stop in each image, the other in opening up one stop for each step. We’ll look at my images next week.

The TOC:

Ansel Adams and the Zone System 0:27
Calibrating your camera for the Zone System 7:00
Plugins in the Forum 9:36
Working with the “Zone Adjustment Plugin”, formerly know as “meaningful Black” 11:25
Detaching menues in GIMP 12:23
Sample Points 12:50
Finding the Dark and Bright point 15:25
Using the plugint 19:40
The proof: white is grey - and black too! 25:25

The image used in this podcast was made during a performance of Pascale Loiseau from the Belgian  WAZOVOL artists group. I found a video of her performance.

Edit: I changed “script” to plugin - there is a bit of confusion….

Creative Commons License This work is licensed under a
Creative Commons Attribution-Share Alike 2.0 Germany License.

Tags: , , ,

10 Responses to “Episode 058: White is Grey - and Black too!”

  1. Jeff says:

    Great video!! Now it is clear to me how to use this plugin to improve my photos the best way!!

    Thanks to all!!

  2. Rolf says:

    It’s just an other way to do it. The same could be achieved with white balance and curves, but I like this approach.

  3. jgack says:

    Nice show! Very nice!!

    At first glance, it seems kind of magic that “zone adjustment” performs the equivalent of white balance (and/or colorcast removal). But the tool’s user interface nicely helps reinforce what’s really going on, and thus it makes sense when you think about it.

    Congratulations on the collaborative development of a great tool! And, of course, a good demo of it’s use and usefulness.

    Oh, BTW, I also applaud the demo of putting the sample points dialog to good use.

    ..jim

  4. Ger says:

    Rolf; As far as I can see the curves tool is a more advanced.
    e.g. You do have the ability to create an S-curve.
    The expert will prefer this although this script “ZA” needs skill and experience
    Furthermore; I agree with Jgack - helps …what’s really going on -

  5. Diego Solís says:

    Great tutorial! Oftentimes, when trying to remove haze or color cast I tend to go to too black and/or too white, which gives me a bad result. The tut helped me get a better balance.
    Also, thank you very much for the plugins, I’m ready to try them.

  6. Rolf says:

    Ger, with the curves tool you have full control. This is a shortcut. Basically it makes an s-curve in each of the three channels, but without user interaction.

  7. jgack says:

    I noticed you mentioned the performer’s name. I am wondering if you knew that because you obtained a model release — and whether model releases are required/recommended for this kind of use of such a photo.

    I might guess that there are fair-use principles for photos of public performers.

    ..jim

  8. Rolf says:

    A public performance is “public” and so I need no model release. She is a “relative Person der Zeitgeschichte”, fair game in context with her performance. And I threw 5€ into the hat. ;-)

    I put some credits to her into the posting, should have thought of that. There is a new video link too, have a look.

  9. jgack says:

    Thanks for the link to a delightful performance!
    ..jim

  10. dino says:

    Hi,

    i never did any gimp scripting does anyone know if it would be possible to not apply the curves directly but open the curve dialog with the automatic set curves? This way you got a nice starting point for corrections and still got full control.

Leave a Reply