Winter is usually a great time for astronomy with longer nights and the sun setting at a reasonable hour. The forecast for last Friday was clear until 12am, enough time for a few hours of imaging. I hadn’t realised it was a waxing gibbous moon until after lugging all the gear outside and setting up.

A nearly full moon, combined with a slightly hazy sky limited the choice of objects severely. The moon was out of the question, as I’ve yet to buy a moon filter, even on the lowest exposure setting of 0.001 seconds the ccd chip was becoming too saturated. So I turned instead to the Orion Nebula, M42.

The usual clouds that seem to be permanently situated above the UK parted for a few days, which finally coincided with a few evenings I had spare. The LX90 hasn’t seen the night sky since way back in March, when I last had it pointing skyward for my first real attempts at collimation.

The seeing over the last few nights, has being poor, with stars twinkling away making achieving critical focus very difficult. The collimation adjustments from March do seem to have improved things, although I still think finer adjustments will be needed on a night with better seeing.

On the first nights outing, Polar alignment was woeful and gotos were constantly 1/4 fov in the finder off. Still, I managed to image a few objects, the two most notable being a double star cluster in Persei and M33 a spiral Galaxy in Triangulum.

GID 23 took place a few weeks ago on the 11th/12th of August.

It all began at approximately 11:01.34pm Saturday night, with nearly half of GID#23 already gone and yet I still had no idea what to do.

Tom suggested I team up with him. We had no idea what the game was going to be about only that it had to involve Tea. A large part of the core code was already in place from previous GID’s Tom had done, which left us free to concentrate on more game specific issues.

The result by the end of Sunday was larger than expected and shows clear signs of the games and tv show we drew inspiration from; Monkey Island, Dizzy and Open All Hours.

For a change the skies were relatively clear on Monday night so I took the opportunity to take a few images. Unfortunately I made a few mistakes during setup that resulted in woeful polar alignment giving a 5 second max exposure time before star trailing became apparent, compared to the usual 5+ minutes I’ve acheived with previous drift aligning… With fog rolling in I had little time to correct it and instead made do.

Despite using the fastest exposure time my ccd camera was capable of 0.001s, the moon was still over exposed. Really a filter will be needed to reduce the light gathered by the scope for future attempts. Still with a bit of post processing I’ve managed to isolate the overexposure to a smaller area.

For anyone that hasn’t already seen it, I’ve posted a Shelled! postmortem over on the GarageGames Site.

You can also download the PDF version.

Hope you all have a Merry Christmas and a Happy New Year!

PS: Guitar Hero ROCKS! Go buy it :)

Shelled! is finally out the door and it’s FREE!

I played for a few hours the other night, with 5 other people, great fun. Very easy for the odd grudge match to develop when you get shelled by another player. The poor AI always takes a pounding in round 1 while everyone tries to stock up on cash for those nukes and high fives.

I’ve been coding a basic line buffer renderer for the XGS, I say basic because firstly it’s two colour (one being black) and secondly it’s still in need of a good optimisation.

The current code takes up just under one page (<512 words). With a lot of spare cycles there’s the opportunity to reduce the code size whilst still meeting the tight timing criteria. The largest chunk of the 512 words is taken up by the numerous uses of the DELAY macro in generating the HSYNC delays, shifting this to a subroutine would make quite a difference.

CGEmpire, a new forum I’ve been reading, posted a challenge to code a procedural texture generator. After seeing some of the examples in the challenge thread it looked interesting enough to have a go at.

I’ve created a DirectX app with a choice between three different texture generation methods. The first two are very simple, random and linear. Random selects a colour for each x,y pixel randomly and as you would expect is pretty much random noise. Linear draws 5 pixel wide alternating white/black bars, again nothing worth showing.

No not the game (although it was a fun game), I’m talking black and white TV, the next evolution of my console. I’d give it a name but it’s currently too close (identical?) to the Pico to be worth it.

R-2R Ladders

I spent the better part of last weekend reading up on nodal analysis to be able to calculate the voltage at each junction of the R-2R ladder that I’ve added. The calculations themselves are simple, just an application of Ohms law. Simplifying the network however took most of the time, at least until the method finally clicked.

Schwassmann-Wachmann 3 otherwise known as Comet 73P is on perhaps its final voyage around the sun. A recent Hubble image shows the disintegration quite clearly:

With a clear night last Monday, I took the opportunity to take a photograph of the comet. Yes I know, its not quite up to Hubble standards. Actually, it’s probably on a par with hubble, prior to STS-61 fixing the mirror anyway ;)