Episode 114: Secrets of a Portaloo!

Download the HD-Video! (74.4 MB, 39:09))
Download the Video for iPods etc (40.0 MB, 39:09)
Download the Companion File! (24.5 MB)

You can win a book in our two contests – the exact rules will be published in the next posting.

I continue to work on my project “Access Control”. My target is a photo book by blurb.com. They accept PDF files for printing – which is important for me because most of the book making software of the printers doesn’t work on Linux. Of course there is an Open Source program for making a PDF – Scribus. It is available for all OS, even OS/2. I’ll tell you about my experience in one of the next episodes.

A bit of Magic is shown by Philippe – and I have confess that I used an old version of his script. You’ll see better ones next time.

There are a lot of photobooks to look at for inspiration at SOFOBOMO.

Then I start to edit an image. The JPEG image is a bit overblown in the highlights and I have to go back to the RAW file. Cropping turns out to be difficult and the image needs a bit of a contrast boost in some parts.

The final steps – sharpening and deciding about a vignette will be made when the layout of the book is clear. For sharpening one needs to kknow the output resolution and size – and I will have to scale the image to 300 DPI before putting it into the book. The vignette depends on the background of the page.


00:20 The Book Challenge
05:20 A Photo Book as the target for “Access Control”
07:50 Scribus for making PDF files
10:00 Photobooks to look at
10:35 Editing an image for the book
11:15 Blown out pixelss
11:45 RAW to the rescue with UFRaw
16:28 Comparing JPEG and UFRaw output
18:50 Correcting a colour cast in UFRaw
20:45 Straightening the image
23:00 Cropping the image
26:50 Improving contrast with a layer in overlay mode and a mask
33:20 Crooping more
35:00 What’s left to do

Creative Commons License
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.

24 thoughts on “Episode 114: Secrets of a Portaloo!

  1. Hmm, the torrent seems to be broken. KTorrent tells me meetthegimp114.mp4 is 949,6MB (!) big. Unless Rolf has gone to 4xHD and 100fps I guess that’s not correct.

  2. There is something wrong with the rss feeds, this episode has the same title as 113, so Miro doesn’t detect it as a new entry.

  3. For the challenge: Is it allowed to use other programs to gimp like ufraw, cinepaint, hugin, qtpfs and graphicsmagick? And shell scripts or own plugins? Especially ufraw and graphicsmagick would be nice, my cam cannot show raw and jpeg at the same time so i only use raw. And for long exposure rows (i plan an hdr panorama from the top of the berlin reichstag) doing everything manually is torture.
    Btw, i don’t need the book, I already got it (both versions, gave the first as present away).

  4. As I haven’t posted the rules already we are very flexible. Every tool from Free Software according to the FSF is legal. That is GNU, BSD, Public Domain and so on.

  5. Looks like the podcast does not work in the itunes player. The feed downloaded but only plays audio without video and the audio skips, also will not sync to my ipod. I will try the links here on the site and watch, but I long for the old podcasts so I can take them with me on my ipod.

    I still appreciate the time, effort, and content.

  6. Ok, torrent is fine now. After several tries I got sensible values. I downloaded the episode directly from the blog and compared, both are identical. (mental note: I have to kil… really really annoy my providers proxy admin, it seriously #%$§!$&!% the torrent file)
    @Rolf, as you have used the raw photo in this episode, I wonder if you know anything about non-Bayer raw images. In theory they should be superiour but according to wp and google they can’t cut a slice. But I have not found any sample images or comparisons.

  7. Non-Bayer, like in Foveon? Only in theory, but that would be a nice thing for the forum. Just start a thread there and tap into the crowd knowledge. ;-)

  8. I’m not sure. I’ve only read about it in an article on technical photography. It states for analytical photos, like in museums when restorating paintings or in police forensic work, bayer sensors can cause problems when shooting very tighly packed color nuances. On the other hand both canon and nikon offer custom ordered fullsize dslrs without the bayer matrix for direct bw photography like for photometric tasks, where only lengths and angles but no colors are needed. I’m not so sure about this, but wouldn’t it be possible to do this directly from the raw files? Or does the bayer filter have other optic influences besides stopping the different wavelengths?

  9. Hello, as downloaded this episode to iTunes I noticed it won’t upload it to my iPod touch. “HD – Does it work in iTunes?” It works if I watch the episode form the desktop only. You mentioned something about a photo book and brought this to mind: http://chrisdesign.wordpress.com/codefree/ an art book I found out about today with beautiful images created with open source software.

  10. Wow, it is really impressive the improvements you are making to these podcasts! The new contest is
    very welcome also, I have been very impressed by the quality and ingenuity of the contest entries. It
    seems there is almost no limit to what can be done.

    While I thought you had reached technical perfection some time ago, you continue to improve the quality
    of these podcasts on all fronts. The new high definition format is very nice, and I also like the introduction.
    Also, Philippe’s eye candy script – very nice!

    This was a very interesting episode to watch. As always, a pleasure to watch your mind at work. I was
    particularly interested to watch you using ‘ufraw’, in fact I followed the trackback from the ‘ufraw’ FAQ
    (the link to this FAQ is posted here at MTG, thank you). A few comments:

    – I noticed you did not have the Yellow Brush depressed. From Pascal’s FAQ:

    Next to the demosaicing algorithm (on the white balance tab) there is a button with a yellow brush on it, which you can enable to smooth the output. Smoothing is (as far as I know) a median filter, which gets rid of some demosaicing artefacts. This is highly recommendable.

    [I also noticed you had 'Film Clipping' enabled. For myself I also have 'Soft Highlights' enabled also.]

    – He also recommends Denoising. As I will be doing this in Gimp, where I have better control over it,
    I generally do not enable this. I do sometimes use the Black Point subtraction, for which I have taken a
    number of exposures at different ISOs in a completely dark room.

    – For the cumbersome straightening process, you could have used Bert’s excellent Straighten&Crop
    plug-in. While you would have still had to go through the lengthy search for a straight section to measure
    against, you might have gotten slightly more accurate results with the plug-in. Then a simple matter to
    undo the crop (leaving just the Straighten) with Ctrl-Z.

    Thank you for taking the time to really go through the cropping process. The way you approached this
    had a nice economy and really emphasized what an important decision this is. I probably would have
    very quickly made a crop much like your first one and then moved on. But the way you determined the
    essential elements and then kept an eye out for negative space was very instructive. And in the end
    the picture was more compelling because of it. Thank you.

  11. Small blown-out reflections are not that evil. I think it should be allowed to have some white pixels in the picture. So I am happy you haven’t spent more time on trying to fix this.

    I really like this versioning functionality of F-spot. To have the image only displayed once and see all versions of it. That’s one of the few parts I really miss in digiKam. Quite nice to see you working with it!

  12. Pingback: The p-Code Machine » UFRaw FAQ

  13. Pingback: MTG: Эпизоды 3 квартала 2009 « Блог фотолюбителя :)

Anything to add from your side of the computer?