Odd cloud effect

Posted on January 10, 2012 by james

I looked out of my office window the other day and saw this:

No idea what caused it. Looks like an aircraft contrail in reverse. Not something I’ve ever noticed before.

Posted in Random | 4 Comments

Google Completely Loses the Plot

Posted on October 11, 2011 by james

Over the last couple of days I’ve been receiving frequent emails containing the tedious witterings of someone I’m barely acquainted with, courtesy of Google+.

I have never told Google I wish to receive email from Google+, so at what point did it become acceptable to allow someone to add my email address to a list of recipients who subsequently receive all their random dribblings every few minutes? And then insist that if I want it to stop, I have to go to their website to get myself off a list I never asked to be on in the first place?

Since Google got so big not to have to care, I guess 🙁

Amazingly, Google seem to think this is The Next Big Thing and that I will be desperate to add my name to their tens of subscribers. Not a chance. I’d rather claw my own eyes out with a rusty fork.

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MythTV/FFmpeg: Part 3

Posted on September 29, 2011 by james

Well, I finally realised that there’s a 0.24 fixes tree for nuvexport that isn’t part of the main MythTV 0.24 fixes tree, so I downloaded that having read on the mailing list that it should work with the MythTV 0.24 fixes FFmpeg.

But no. It doesn’t. 0.24 fixes nuvexport attempts to use options for padding and cropping that are no longer supported by 0.24 fixes FFmpeg.

I was on the point of abandoning FFmpeg and going back to using the transcode option until I discovered that it is no longer supported, so I just had to give things one more try. I installed FFmpeg 0.8.4, ignoring the MythTV version, symlinked it to “mythffmpeg” and installed the latest version of nuvexport from github, ignoring the 0.24 fixes release.

So far that appears to be working.

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MythTV/FFmpeg: Part 2

Posted on September 28, 2011 by james

Enabling mp3 encoding in the bundled version of ffmpeg was merely a case of adding

--enable-libmp3lame

to the configure command for the entire package. nuvexport-xvid now runs to completion.

Unfortunately the output looks all wrong, so I’m back to the drawing board. I suspect my aspect ratio fix.

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Trials and Tribulations with MythTV and FFmpeg

Posted on September 27, 2011 by james

I’m running MythTV 0.24.1 at the moment with quite a few MythBuntu and other front ends. I’m running out of disk for recordings and decided to archive a few off to release some space which I’ve done with previous versions of MythTV fairly regularly. Unfortunately I discovered fairly quickly that asking nuvexport to transcode recordings to my preferred format (XviD) using ffmpeg was badly broken.

MythTV now includes its own copy of ffmpeg in the distribution to try to control some of the rapid changes of command line parameters the ffmpeg team seem to inflict on us with monotonous regularity. I discovered that it didn’t support libxvid out of the box for some reason (perhaps I didn’t have the necessary libraries installed at the time I built it). So, first step was to reconfigure it and rebuild. Only it won’t. The ffmpeg shipped with 0.24.1 looks like it just won’t link when libxvid is enabled.

So, I downloaded the latest git release and tried that. ffmpeg would now build, but doesn’t like that the libraries aren’t quite the same as the 0.24.1 versions, so I ended up rebuilding the entire package from the source, discovering in the process that libxvid wasn’t enabled again…

Eventually it dawned on my that I needed to add the command line switches:

--enable-libxvid --enable-gpl

on the mythTV configure command and this time all was well.

After reinstalling I kicked off nuvexport once more only to discover that it failed yet again, but this time because ffmpeg was being called with a parameter:

setsar=1

which the MythTV version of ffmpeg doesn’t support — it’s a later change to the code. I discovered that the older version of the parameter is:

aspect=1

So I edited /usr/local/share/nuvexport/export/ffmpeg.pm around line 335 to change:

push @filters, "setsar=1";

to

push @filters, "aspect=1";

This fixed the problem entirely and I got a full first encoding pass from nuvexport. Now it just falls over because ffmpeg doesn’t support the mp3 codec. That’s something to look at tomorrow.

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Jupiter and Moons

Posted on September 27, 2011 by james

Since Jupiter is returning to our skies now I thought I’d take advantage of last Thursday’s clear-ish skies to do some imaging practice with my 127 Mak and SPC900. I’ve not been through all the clips I took with my Ultima barlow yet, but this one was the first sequence I took. It’s not a great image, but I like it because during processing I discovered I’d caught three of the Jovian moons as well — Io, Callisto and Europa (Europa is on its own on the right).

Not sure why the bottom left of the planet has been “ground off”. I think it’s a processing artefact. I’ll have another look some time.

Image details:

127 Mak on an EQ3-2, SPC900, 1200 of 2400 frames stacked in Registax 6.

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New Life…

Posted on September 19, 2011 by james

Our chickens are kept in large fenced runs (to keep out the foxes) in the orchard with the trees providing some shade from the fierce heat of the British Summer. The birds are rotated around the pens giving them fresh grass on an irregular basis (ie. when the fierce heat of the British Summer means that the runs currently in use are a complete mudbath).

Almost a month ago one of the hens disappeared. I was forced to assume that she’d roosted high enough in a tree to allow her to fly outside the fence in the morning and had become breakfast for a local fox family. A couple of mornings ago however I found her hiding in the undergrowth. She’d got into one of the unused runs and laid a number of eggs that she’d been sitting on for the last three weeks. Here’s how I found her:

Sadly only two of the eggs had hatched and I assume that one of the chicks didn’t make the trip as I could only find the one, but perhaps given the time of year that’s not such a bad thing. The new one is going to have its work cut out surviving as it is. It probably won’t even be fully feathered and able to keep itself warm until the end of October.

I’m keeping an eye on them and hoping that the next few weeks are mild enough for the chick to survive.

Posted in Chickens, Smallholding | Leave a comment

8GB Memory Upgrade for HP Proliant Microserver

Posted on September 19, 2011 by james

I decided to upgrade the server to 8GB RAM (its default configuration is 1GB). The motherboard has two RAM sockets, so I purchased a pair of 4GB RAM sticks to put in. It’s not a difficult job, only taking ten to fifteen minutes, but it helps to have small fingers.

To fit the RAM it’s necessary to remove the motherboard. It slides out from the bottom of the unit, but it’s a bit fiddly. First thing is to undo the two blue-headed bolts at the front of the board using the key clipped inside the door to allow the board to slide forward a little:

That done it’s possible to remove the two cables routed down the left hand side, including the connector for the disk array (which is awkward if you have large fingers) and the three on the right hand side — two USB headers and the switch/LED connector block:

With those removed the board will slide out a little further allowing the power connector to be removed, and then it will come out completely:

Removal of the old DIMM and replacement with the new ones is straightforward:

And then as it says in all the good Haynes manuals, “reassembly is the reverse of removal”. First slide the board back in and replace the power connector:

Then slide the board in far enough to reconnect all the other cables:

And finally push the board home, do up the blue bolts again, re-seat the cables in the clips and route the power connector cable under the motherboard “handle”:

Boot up the server once more and you’re sorted:

$ ssh root@gamay head /proc/meminfo
root@gamay's password: 
MemTotal:        8051332 kB
MemFree:         7845936 kB
Buffers:           11612 kB
Cached:            64960 kB
SwapCached:            0 kB

Posted in Computing | 2 Comments

Clearer Boards

Posted on September 14, 2011 by james

Back in the Spring when I wanted to take the OSR honey off some hives I had a real problem getting the bees to vacate the supers. Up until now I’ve always used a crown board fitted with Porter bee escapes, but despite having cleaned and adjusted them the bees just weren’t interested in leaving the supers. I also tried a friend’s clearer board which used cones at the centre and each corner, but that didn’t work well either.

So, for taking this Summer’s harvest I decided I’d try some other designs of clearer out. I bought a few of the rhombus clearers from Thorne and made up a board to suit:

The board is a piece of 18″ square 12mm ply, with 25mm “walls” on the bottom to give the bees a bit more space underneath and 12mm on the top. The hole in the middle is 38mm, purely because I happened to have a hole saw that size.

These worked quite well, the only problem being one where the supers turned out not to be entirely bee-tight. I’ll certainly give them a go again next year. I’d only bought three rhombus escapes and needed four new boards, so I also took a look around Dave Cushman’s beekeeping equipment plans and decided to have a go at making a square vortex-style escape:

Again the main board is 12mm ply with 25mm walls below and 12mm above, and the “vortex” is made from 6mm ply spaced so that a standard hexagonal section pencil would just rotate in the gaps. The 6mm ply was nailed and glued to the base. Once in place, I cut down a piece of mesh to fit over the top and fixed it in place using a staple gun. Again the central hole is 38mm.

This turned out to work exceptionally well and I’m very impressed with it. I shall definitely make up some more for next year and give up on the crown board/Porter escape combination altogether.

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Google Sketchup on Ubuntu 11.04

Posted on September 13, 2011 by james

For designing the observatory I really needed something a bit more “touchy-feely” than pencil and paper — my usual method of designing bits and pieces I build. A few people had mentioned Google Sketchup, but it’s only available for Windows and Mac and I don’t do either of those as a rule. I’m a UNIX/Linux user of twenty-five years or thereabouts and I just can’t get on with Windows.

The obvious solution was to try installing the Windows version under WINE. A fair bit of mucking about later and I was no further forward, but eventually I discovered “Winetricks” and it’s own installer for Sketchup. Another few minutes and I was up and running.

The learning curve is fairly steep, but Google’s video tutorials are very helpful at leading you through the basics. It’s entirely possible that attempting to design an observatory as my first project was excessively ambitious, but if what I wanted were that much simpler I’d never have bothered anyhow.
Thus far it’s been an excellent tool for visualising what I have in my head and making sure it stands a chance of working in real life. So much so that I’ve already started using it for other projects such as my ongoing bathroom build. I highly recommend it, but don’t expect to be able to use it as a CAD tool. That’s really not what it’s about.

Visit the 3D Warehouse to see what other people have got up to with it. I downloaded a number of things from that site to help out with and incorporate into my own designs.

I’ll post some images of what I’ve been doing with it shortly.

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