I’m still testing out some of the advanced features of using Tachyon to render nice images of biological macromolecules. I came across these beautiful images of bacteria which are able to consume radioactive waste, and decided to tinker a bit to see if I could get something similar out of VMD.

First of all I loaded in my molecule and set it up similar to the exercises from the other day: white background, surface representation, diffuse material. I also added the Depth Cue feature of VMD, which adds a fog which increases in density with depth. This helps to add a bit of a 3D feel to the representation. I also played around with the various lights, settling on having lights 0 & 2 on.
I rendered the image with:

"/usr/local/lib/vmd/tachyon_LINUX" -aasamples 4 -rescale_lights 0.3 -add_skylight 0.9 %s -format TARGA -o %s.tga

Note: this takes about 8 minutes to render on my laptop at about 700×700 resolution.
If my understanding is correct, this should give a scene that is dominated a fair bit by the skylight parameter, and this is more or less the case. The image, while interesting in some ways, is far too bright!
Let’s drop the skylight down then:

"/usr/local/lib/vmd/tachyon_LINUX" -aasamples 4 -rescale_lights 0.3 -add_skylight 0.6 %s -format TARGA -o %s.tga

Well that darkened the shadows a bit, but the overall image is still way too bright. How about dropping the lights?

"/usr/local/lib/vmd/tachyon_LINUX" -aasamples 4 -rescale_lights 0.1 -add_skylight 0.6 %s -format TARGA -o %s.tga

Well, still far too light. What’s happening is that the depth cue fades the image to the background color (in this case white) as it goes. Let’s drop the depth cue density in order to cut back on the lightening. This setting is found in Display–>Display Settings. I adjusted it to a value of 0.15, still using the Exp2 function for the density. When I rendered this (using the same settings as the last one above, it looked OK, but not fantastic. Mostly it was just “flat”, if that makes sense - not a lot of visual appeal. I rescaled the lights back up to 0.3, and this was better.

Something still isn’t “there”, though. To be sure, the tachyon renders look nice, but I just don’t feel like this is the best that can be done. I’ll have to keep toying with it.

I’ve been using Ubuntu as my operating system at work for about 2 years now. I really love it. I’ve tinkered with making it the OS on my home computer, but since I do a bit of gaming I keep putting it off (as gaming support in Linux tends to lag behind Windows a bit).

I’ve been getting more and more fed up with Windows lately, however, so I’ve decided to give Linux another go. I’ll be liveblogging the changeover for you below.

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I enter a few online image manipulation competitions from time to time. It’s fun, and I’ve learned a lot about Photoshop that has come in handy for other work, such as making graphics for presentations or the web.

I thought today I’d do a bit of a liveblog while I worked on an entry. Hope you enjoy

I’ll be doing an entry for the Woot weekly contest. They usually provide a theme, and the rest is up to the entrant. The theme this week is:

Show us a past or present woot brought down by scandal.

Let’s get this liveblog started.

8:00 - Brainstorming: This actually probably really started right after I saw the theme yesterday. This morning, however, I start sort of thinking a bit harder. At this time I think I want to do a play on the Teapot Dome scandal.

8:20 - Go back to contest description, look at already posted entries: Here I like to read the contest listing again, to make sure that I haven’t missed anything. Sometimes this gives me new inspiration or perhaps makes an idea I’ve come up with sound dumb. Not so much today. Also, I flip through the entries that are already posted to make sure that someone hasn’t already done something similar to mine. Thankfully, most of the entries so far are some play on drugs, Elvis, or both.

8:25 - Look up the Teapot Dome Scandal

8:27 - Start trying to figure out how to implement this cockamamie idea

8:33 - Look for source images: A source image can make or break a photoshop entry. I want to do an old newspaper, so off we go to the magical Flickr to search for them. After a bit of searching, I found a series of Yorkshire Evening Post snapshots from the 1940s, by Flickr user Mig_R. I really like the look of these, so let’s choose one as our starting point.

8:40 - Find the Font(s): Since I need to change the headline of the paper to a U.S. city, I’ll need that font. I use WhatTheFont along with a cropped image of the headline to identify a close match. It turns up Fette Gotisch, which is a fine font which unfortunately costs cash money. Time to do more searching. Finally I took the easy way out: since I only need a few words, I simply put those into one of the “try this font” boxes on a site trying to sell me the package. Nab a screenshot of the “test” and we are good to go. I used the clone stamp tool to erase “Yorkshire”, pasted the new city name in, and set the blending mode to “multiply” to remove the white background. After that I played with the hue/saturation, curves (drop in red, raise the green), and opacity to get it to match the rest of the text as much as possible. Finally I applied a layer mask and used a “grunge” brush in black to knock out little specks of the text.

To do the other bits of the masthead, I simply matched fonts from my machine and typed in what I wanted.

9:16 - Text work: Replacing all the text of the paper is quite a chore. You have to do a lot of careful work with the clone stamp tool so that the erased text doesn’t look too fake, then of course generate the replacement stuff. Here I decided that the scandal would be “Craps for wine”, in which people who wanted to get a Bag of Crap (Woot’s most famous offering probably) were required to send bottles of wine to the staffers, which they would then use to run Wine.woot.

10:00 - The image: To create the Bag of Crap image, I used the poster edges filter in order to get nice dark lines on the edges of the source. I set the blending mode to multiply again, dropped the opacity a tad, and played with the hue/saturation once again to get it to blend in with the vintage newspaper feel.

10:15 - More text work: Finally I did some ancillary text stuff to tie it in with the Teapot dome scandal (a minor occurrence in this paper’s reporting) and sort of wrap the whole thing up.

10:30 - I think I’m done, time to step away. Click the image for the full version:

Sometimes I’ll go back and make more edits later.  More often I’m sick of looking at the entry, and tend to purposefully delete the PSD file so I can’t fall prey to the endless tweaks.  I think we’ll go with the latter this week.  2 hours is about my limit for one entry.