Download the Video! (37.8 MB, 19:53)

Download the Torrent!
(Mobile version tomorrow)

The German word “Terrorie” was coined by a kid in a Physics lesson of my late colleague Helmut Mohr in Hamburg. It is what it sounds like – and today’s video is full of it. No GIMP, no images, only the blackboard and me talking. Please consider this as a WARNING.

We had a lively discussion in the forum about the theory behind making images, circling around the term “dynamic range”. There is a big difference between light and dark parts of our world, often more that a camera can catch. And nearly always more than fits onto paper or a computer screen.

The process of squeezing this big range into the small output range is called Post Processing. Either you do it via RAW anf GIMP – or the smart chip in your camera does it while saving your iage as JPEG. What I forgot to say – if you do it, you can redo it. The RAW file still exists. If the chip does it, the RAW file is discarded and you are stuck with the version of the image made by the chip.

I got a lot of information about this subject from a wonderful paper by Karl Lang at Adobe(R). Worth to download and read, even if you decide to skip the video this week.

The TOC

02:04 Orders of Magnitude
04:00 How much light is in a scene? (Dynamic range ramp up)
06:00 There is no black and white
06:30 Dynamic range of a scene
06:50 Dynamic range of LCD and prints
08:50 Dynamic range of the camera
09:50 Exposure = slide the dynamic range
11:05 Post processing by the camera
12:15 RAW -> GIMP -> print
13:00 Slides and egatives in analog photography
15:05 A source at Adobe(R)
15:15 8 Bits – a problem (sometimes)
17:10 Why is it possible to make images? Because our eyes are no camera and our brain no computer.

“Meet the GIMP”  by Rolf Steinort is licensed under a Creative Commons Attribution-No Derivative Works 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: 8 Bit, dynamic range, post processing, raw
Posted in Gimp video tutorial, Photography technical basics | 12 Comments »

Download the Video! (31.0 MB, 16:18)
Download the Video for mobile devices! (29.8 MB, 16:18)
Download the Torrent!
Download the Companion File!

This week I have a challenge for you. Do my homework and edit my shot from our Samba Carneval. You’ll find the JPEG and the NEF (RAW image by a Nikon D200) of a shot I did from my window. It is not a good photograph but catches a beautiful moment. Improve the image, store it somewhere on the Internet and post a link to it in the comments. You can embed a small version of it in a comment, just copy the HTML code from 23, flickr or other sites. It should be there in a box to cut and paste.

Then I’ll tell you why you always shall set your camera settings to a defined standard state before you put your camera in the bag or cupboard. I didn’t and it has ruined a whole series of shots from this occasion.

Have you ever wondered how to make a selection with a zig-zag border? Well, if you have, I have the answer. (Stolen from Saul Goode, BTW ) I was reminded that a Quickmask is an image and so can be editied much better than a selection. Making waves and sawteeth into it then is “elementary”.

And finally I reveal how I built a dust free blackboard and chalk with GIMP. The blackboard from the “Basics” series looses its mystery.

I made a TOC and forgot to save it.

Tags: blackboard, chalk, challenge, editing a selection, quickmask, selection
Posted in Gimp, Gimp video tutorial | 14 Comments »

Download the Video! (59.0 MB, 31:03)
Download the Torrent!
The Video for Mobile Devices! (57.3 MB, 31:03)
Download the Companion File!

This week there is only a little bit of GIMP, but a lot more about the free video editor Cinelerra. I use it to make a kind of slide show video used to illustrate a short “bumper” for Martin Bailey’s blog and podcast about his (mostly nature) photography. Martin is living in Japan and has a lot to tell about photography and Japan. Highly recommended!

Cinelerra is a full “non linear” video editor for Linux – and so perhaps a bit overkill for making a slide show. Non linear says that the program does not change the video and sound data and that you can access all your media easy and fast because only references are moved around. I forgot to introduce it properly at the start of the video. There are programs around for Windows and MacOS which do the same, I am sure.

Cinelerra comes in a lot of different flavours. I take the version from cinelerra.org.

The final version of the bumper, the used images and the Cinelerra XML file are in the companion file.

And here are, as promised, my settings. Compare if you have problems, my setup is running, but I am not sure why….

Playback – check for “Stop playback locks up” if you encounter stutter – uncheck “Play every frame” for performance

Recording – Important is the last point about images

Performance

Interface – Check “Show Thumbnails”

About – for version information

This week we have a mobile version of the video again. It’s not on the feed, because I don’t know if this version fills your needs. So feedback please!

Sorry, I could not make a TOC this time, too much school stuff around.

Meet the GIMP Episode 132 by Rolf Steinort is licensed under a Creative Commons Attribution-No Derivative Works 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: cinelerra, slde show
Posted in Gimp, Gimp video tutorial, Other OS software, Photocast Network | 8 Comments »

Download the Video! (57.9 MB, 30:27)
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After a bit of “housekeeping”, which includes thanks to contributors and a nod over to the Focus Ring, I try to use the stuff hidden in the <Image>/Color/Auto menu. My results are not that good and I try to do it better with curves.

Why did I fail? No idea, it may be the software or perhaps my choice of image was bad. Please share your experiences with this option.

At the end of the show I lift the secret behind the numbers 1 – 1.4 – 2 – 2.8 – 4 – 5.6 – 11 – 16 – 22 …. – aperture numbers decoded.

I couldn’t decide which of the two shots I made for the show image should go into the post, so here are both.

The TOC

00:20 Starting 2010 – thanks and a guy selling GIMP
04:30 New Forum policy
05:40 New Focus Ring Episode
07:00 Exporting an image from F-Spot to GIMP
07:20 The Histogram shows underexposure
08:00 Exploring /Colors/Auto
09:15 Equalize, stretch contrast, stretch HSV
11:50 Color Enhance
12:50 The manual curves approach
15:30 Unsharp Maks (USM) for getting details in snow
17:00 Selection with layer mask
19:00 Basics: Apperture numbers explained

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Posted in Gimp, Gimp video tutorial | 17 Comments »

Download the Video! (61.2 MB, 32:10)
Download the Torrent!
Download the Companion File! (767 Bytes!)

Sorry, again a “Nerd Show”. I tackle some problems that have come up with the Python script of the last week and show my way to debug and test while making errors. My first error was to take a test case without colours – my script from last week changed all images to greyscale. Then I learn something useful about merging layers in Python.

But the top of the show is even more nerdy – the Octave plugin allows to access the Octave math software from GIMP. Caluculate your images or do a FFT with them.

The scripters crowd in the forum found a bug in GIMP, saulgoode reported it and it got fixed in a day. Take that, Adobe!

Then I try to explain why the big blobs in the image featured two shows ago are not made with GIMP but with pure physics in the camera. You can see a Blender video I made about this for #200 of Chris Marquards Tips from the Top Floor show. My part starts at about 11:40 and contains an embarrassing error. Do you get it?

This image by Nachbarnebenan is a good example for a shallow DoF.

The next show will be a simple, non-nerd walk through the post processing of an image. Promised.

The TOC

01:10 Octave Math Plugin
02:10 Number types in Python
06:00 Making a test case
06:30 Finding the wrong layer mode
08:00 Running into a wall and thinking around it
09:40 Isolate the bug
12:40 Cleaning up the code
14:40 Colour halos wit Normal Mode sharpening
16:40 When to use Octave sharpening
17:10 Basics of Photography – Depth of Field and Bokeh
19:00 Image creation with a lens
21:00 Circle of Confusion
22:30 Depth of Field
25:00 Apperture and DoF
28:30 DoF and sensor size
29:00 Dofmaster
30:00 Focal length and DoF

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: Depth of Field, DoF, Programming, python
Posted in Gimp, Gimp video tutorial, Programming | 32 Comments »

Download the Video! (77.0 MB, 40:31)
Download the Torrent!
Download the Companion File!

This is the second time I try to get into Python scripting for GIMP. My script in the first show about scripting was simple, just saving some clicks. Now it is more complicated, variables, loops and floating points included. But no parrots!

You find a better version of the programs in the companion file. Following a tip in our Forum I included a Undo Group. So the action can be undone, a behaviour that should have been included from the start.

I mentioned some sources. Instant Python, the official Python Tutorial and the GIMP Python reference. Bert has a script page and a much better version of the Octave sharpening script.

Then we have a UnGIMP composition challenge on the Forum.

Have I forgotten some promised links? Please complain below!

Errata:

The loop counter in the companion file is set to 6 instead of 4. You can change it back or leave it.

Perhaps it is better to take the image size from drw instead of img. See the discussion in the forum. drw.height and drw.width should work also when the layer is smaller than the image.

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: octave sharpening, Programming, python, script, sharpening
Posted in Gimp, Gimp video tutorial, Programming | 37 Comments »

Download the Video! (32.7 MB, 17:13)
Download the Torrent! (working!)

If you have problems with the sound – simply reload! There was a glitch.

I was out on a photo walk with a GIMPer from Bremen. One of these shots is post processed in this show. Nothing special, just adjusting the colours with a curve in two different parts of the image. Of course a layer with mask is used to separate the different areas and explained again for the new GIMP users.

The really new information is about uploading images from F-SPOT to 23 and flickr. You have to enable the exporter in the menu Edit/Mange Extensions/Export. 23 is covered by the flickr exporter, they use the same API.

You can find the final image on 23 and flickr, both uploads worked like a charm.

You can participate in episode planning in the Wave. It is open for everybody.

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: beginner, F-Spot, layer, layer mask, upload
Posted in Gimp, Gimp video tutorial | 9 Comments »

Download the Video! (22.6 MB, 11:53)
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Sorry – no mobile version yet!

A short one this time – I upgraded to Karmic Koala and did a clean install with new partitions and EXT4 file system. And now I am getting the important stuff back on the disk and leave the cruft out. This meant that a lot of the files needed for a proper podcast are still on the external disks.

I take a look a the new Folio by Jeff Curto at Lenswork – because it’s an example of printing an image on paper with a different aspect ratio, the images are really good and Jeff is a friend and I hope he sells a lot of them.  Jeff does two podcasts in the Photocast Network, Camera Position and The History of Photography. The last is the only podcast where I have experienced a coffee break.

I use an image from “wbool63″ from the forum to make some nice frames with G’MIC, the Swiss Knife plugin from France.

And I have done….

The TOC

00:20 Greetings and Jeff Curto at lenswork
02:30 Using a white frame and text
03:10 Cropping an image
05:50 Getting a square crop
06:20 Eyes out of focus – no problem here
07:10 G’MIC plugin and frames

No blackboard this time – and no mobile version  yet. The upgrade broke the toolchain, I have to compile ffmpeg to get it running again. Software patents are really …….

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: cropping, G'MIC
Posted in Friends, Gimp, Gimp video tutorial | 5 Comments »

Download the Video! (53.7 MB, 28:14)
Download the Video for iPods etc (24.1 MB, 28:14)
Download the Torrent! (likely broken)

There are a lot of tutorials out there for “The Other Program”, also called Adobe(R) Photoshop(R). (I hope I got the Rs right, can’t find the page where Adobe(R) told the world how to call this program.) A lot of that stuff is easily translated to GIMP, but there are some serious differences. One are the “Adjustment(R) Layers(R)”. This is a way of applying a curve, gradient, hue or saturation change…..  without changing the real image. You can come back later and tweak the curve or the slider – non destructive editing.

There is an easy way to work around this: make a new layer of the visible image and work on that. You have to redo that, if you decide to change something in the lower layers.

To show how to do this I have ripped out a part of John Arnold’s Photowalkthrough podcast and redone the same in GIMP. Photowalktrough is a really good resource for everybody who is into the digital darkroom – independent from the program used. And John has his #100 out! Congratulations!

GIMP will have non destructive editing in a year or two – it’s the main reason for getting GEGL into GIMP and making this big effort of writing a lot of the program again.

In the second part of the show I get the blackboard out and start a new segment in the show. I try to explain how  film and sensors are working. I’ll expose you to some of these lessons for about 5 to 190 minutes and will then decide upon your reaction if I should keep this on. I’ll have them at the end of the show – if you are bored you can just skip the rest.

Sorry, there is no TOC up to now. the moment Kevin made one.

The TOC

00:28 Welcome to PhotoWalkThrough.com from John Arnold
01:05 Welcome to Meet The Gimp from Rolf
02:30 Back to John
02:50 – a curves layer
05:10 – a layer mask
08:20 Back to Rolf
09:00 The original photo
09:20 Make a layer with increased saturation
10:40 Add a gradient layer in soft light mode to alter the sky
12:10 New layer from visible
13:25 Add a layer mask and edit it
15:25 The problem with destructive editing
15:55 But it’s not that big a problem
18:20 New segment – time for lessons
19:55 How film works
24:00 How a sensor works
27:00 Feedback please
28:14 The End

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Posted in Gimp, Gimp video tutorial, Photography technical basics | 16 Comments »

Download the Video! (58.1 MB, 30:32)
Download the Video for iPods etc (37.1 MB, 30:32)
Download the Torrent! (likely broken)

The results of the Book Challenge have been so interesting that I have made two shows out of them. This is the second part.

If you want to buy Akkana Peck’s book from amazon.com in the US, go to her website and use her link. She gets a bit more money out of it and you pay the same.

The TOC

00:50 Threshold tool revisited
02:40 Ityker’s image
04:00 Selective decolorisation
05:00 Layer mask for selective decolorisation
05:00 Layer mask shortcuts
06:00 Duotone
08:45 Sample points
10:00 Preventing tonal change of the colorisation layer
11:10 Sharpening layer
12:50 Fake view cam cassete shadow
14:30 Mathias’ image
15:50 Image sources
17:00 Layers for ressources
18:40 Combining different exposures
19:25 Healing spots and bra straps
20:30 Layers for sculpting the hair
22:40 The sky – overlay mode
23:50 The sign
24:00 Layer groups
25:00 Dodge and burn on a layer in soft light mode
26:00 Unsharp mask for enhancing local and global contrast
27:20 The John Arnold Style Vignette(R)

Meet the GIMP Video Podcast by Rolf Steinort and Philippe Demartin is licensed under a Creative Commons Attribution-Share Alike 3.0 Germany License.
Permissions beyond the scope of this license may be available at http://meetthegimp.org.

Tags: challenge, layers
Posted in Gimp, Gimp video tutorial | 6 Comments »