DorkMatter.net

I happen to think Infrared photography is pretty cool though I realise it’s not to everyone’s tastes. Since I work in digital and don’t own an Infrared filter I wanted to create an Infrared-like effect.

So to start open up your photograph in GIMP. This is the file I’ll be working with.

Distorting the colours is really easy. Open up the Hue/Saturation/Lightness menu, Colours>Hue-Saturation… and play around with the hue until you get some colours you like. I chose to shift the hue to 180 and pushed the saturation right up to accentuate the colours. If you wanted something subtler you could keep the saturation closer to the middle of the slider.

I could leave it there but I don’t really like myself with green hair. Purple suited me much better. And looking at the photograph I like the sepia quality to my clothes and camera so I’m going to match my head and hands with my clothing.

More recent versions of GIMP come with the coolest selection tool – Foreground Select.
Here’s how:

Zoom right into the area you’ll be working on; if you try zooming out half way through you’ll lose your selection and will have to start over. Choose the Foreground Select Tool and start roughly marking out the area you want to select using the lasso cursor. You don’t need to be too careful with this but try to avoid crossing into areas you don’t want to select (the foliage in this case). When you’re finished you’ll have a large coloured area. Now use the brush cursor to select any areas you missed with the lasso. It will automatically select areas of similar colour nearby.

Picture shows after lassoeing but before tidying it up with the brush.

Press Enter to view your selection.

If you’ve missed anything you can repeat the process. Just make sure the Add to Selection button has been selected.

I probably could have selected that a bit better but you get the idea. I had to redo this for the tutorial so I got a bit lazy. I’d also recommend not saving it as a jpg until you’re done or you’ll have hideous pixelation like I had.

Anyway, now to make my head match with my clothes I’m going to apply a sepia tone. For this go to Colours>Colourise and slide the Hue slider around until you get something orange-brown in colour. Play around with it and see if you need to reduce the saturation.

And here’s how it looks when you’ve selected and coloured all the parts.

If you want to have a go with this particular photo you can download it.

View License

When I was making the title image for this site I started with the idea of a swish – those wave shapes above. Initially I tried drawing by hand with the pencil tool but even with a tablet my drawing was too shaky. It would have taken a lot of node editing to get that looking even slightly smooth. Next I tried using Bezier curves to construct the shape but after joining all the lines it just looked kind of of messy.

To get a smooth looking shape I needed a more simple approach. So here’s how I ended up with a smooth shape.

The shape is basically a triangle – thick at one side and tapering into a point. So start by drawing a triangle with the polygon tool.

Next you’ll need to edit the triangle’s path to create the curves, but before you can edit the path you’ll need to change it from an object to a path. Path>Object to Path will do this. Choose the Edit Paths by Nodes tool and select the image to see the nodes.
Stretch the triangle out so it forms the basic shape of the wave you’re making. It will probably look something like this now:

To create the curves start by working on the nodes that lie between the base and the tip of your triangle shape. You can tell by the sharp angles between the lines that these are corner nodes. To smoothen that, out make the node symmetric.

You can see the angle has been smoothed out into a curve. Repeat with the node below.
Now you can move your curved areas around to make the beginnings of a wave. In the picture below I’ve moved the top node up and left slightly and the lower node up and right. I’ve tilted the curve by moving the Bezier handles up and down until I’m happy with the shape. You’ll also notice the top right-most node has been moved down to make the base of the shape more narrow.

To add another curve I add two nodes (top and bottom) between the curve and the point and repeat the process to create the new curve. To add more nodes shift-click on the two nodes you wish to add a node between and click the Insert Node button.
In the same way as you did above, play around with positioning the nodes and moving the Bezier handles until you end up with a curve you like. Here’s a pic showing the position of each node’s handles.

And that’s it – a pretty easy way to get a smooth curved shape.

If you give this a try please comment below and let me know, or if you have an alternative method I’d love to know.

I’m never sure what to put as a first post on a blog so why don’t you have a look at the About page if you’ve just found yourself here by accident.

I’ve been cooking again. This time a baked cheesecake and some pistachio ice cream. I think I already mentioned my unhealthy interest in pistachios. I made too much again though.

The cheesecake is made of a biscuit base, a layer of cream cheese, egg and sugar and another layer of sour cream and sugar, all flavoured vanilla. The toping is raspberries and sugar and smells like jam.

I made the ice cream using double cream and yoghurt and a load of pistachio nuts. No ice cream machine required. I just had to fork it through when it set at the edges and then leave it to freeze. Pretty easy.

Still no chilli seedlings to show. We poked around and dug some up to check. They’re starting to germinate. 7-10 days the packet said… but it’s been 2 weeks!