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Archive for August, 2010

How things change

August 13th, 2010 No comments

Recently, I would say that photography is my favourite hobby. But it wasn’t always that way.

Throughout my childhood, I’ve taken pictures of important occasions on single-use cameras. My parents would always buy me a single-use camera before a family holiday, for example. I wasn’t interested in the camera, though.

A few years ago (2005, I think) I lived in hall of residence with a guy who had a “fancy camera”. I was so uninterested in it that I have no idea what it actually was. It was digital, and it had a big lens on it. This just goes to show that I didn’t care about photography at the time.

More recently, in 2007, I had a Sony Ericsson K800i camera phone. For a phone, it had an extremely decent camera and could compete with some of the entry-level digital compacts available at the time. But I still only really used it for taking photos of things that were happening around me.

But then, my colleague Paul starting doing his photo-a-day in 2008. I became a keen follower of his photo blog, and started to take “arty” shots on my phone. I enjoyed it so much that I quickly ran into the limitations of my phone and started wondering about buying a “real” camera.

There was a decent superzoom “bridge” camera in the office so I borrowed this for a few days and had great fun with it. Then unfortunately I was involved in an accident and dislocated my shoulder. Stuck at home, bored, I bought a camera. It was a bridge camera, one mark up on the one I’d borrowed from work. I bought it primarily as a high-tech toy, and with not much interest in the art of photography.

This was the stimulus I needed, and with a powerful and versatile camera I tried all sorts of photography. Gradually I became interested in the art of taking photos, and I now try to take photos that are nice to look at, as well as fun to take.

In 2009, I was given an unwanted 35mm SLR. At first I was sceptical – how useful could film be? I bought some film and had a go. I really enjoyed using an SLR for the first time and immediately wanted a DSLR.

In 2010, I caved in and bought a DSLR. I also continued shooting film and I now have a collection of around ten cameras – all film except for the DSLR. I’m still more interested in the cameras and the techniques in using them, but I hope that my work is also pleasing to look at. Make up your own mind.

Categories: Gadgets, Photography Tags: , , ,

Building an email server using ClearOS

August 5th, 2010 4 comments

I’ve had a server at home for years now, and I’ve also been a professional sysadmin for at least three years. I know my way around Linux pretty well and for some time I’ve run my own web server and also other services.

But one thing I’ve steered clear of until now is running my own email server.

I’ve always thought it would be fairly easy to set up, but much harder to make secure. I don’t want to receive tonnes of spam and I don’t want spammers using my SMTP server as an open relay. In the past I’ve read about building SMTP servers with sendmail, postfix and exim but there was all sorts of conflicting information when it came to integrating milters and so on. Different guides all seemed to give contradictory advice and require all sorts of strange configuration steps that I couldn’t understand.

But all that changed when I heard about ClearOS. In short, it’s a spin of CentOS which uses a custom web interface to configure various software “modules”, including things like web server, email server, firewall gateway, database server, and so on.

I installed it on a virtual machine and after only a few clicks I was running a mail server: an MX for receiving mail for my domains, an authenticated SMTP server for personal outgoing mail, and a secure IMAP server for storing and accessing my mail. The frontend sets up postfix and cyrus to do its dirty work.

For ultimate ease, users (just me, in this case) are authenticated using a local LDAP directory, rather than by using system accounts. All SSL certificates for IMAPS and HTTPS were added automatically. Email antivirus scanning is done by Amavis and spam filtering is done by Spamassassin.

I had a little bit of trouble setting up Horde to access webmail and a web interface for configuring sieve rules. By “trouble” I mean the default Apache virtual host declarations needed some changing around and some aliases adding. If you’re familiar with Apache this won’t be a problem.

There are some aspects of ClearOS I don’t like so much, and I would prefer to use CentOS. But now ClearOS has written out all my configs it should be trivial to move my new mail setup to a plain old CentOS installation, where I already run my websites from. I have definitely learnt a lot about how email works by simply reading and understanding the config files written by the frontend.

So if you want to build an email server but don’t know where to start – try ClearOS. It’s a great introduction to the “scary” parts of setting up an email server, like milters and certificates.

Flashbulbs

August 5th, 2010 No comments

A while back, I bought a Conway Synchronised box camera which came with a Coro Flash included. More recently I managed to get hold of some flash bulbs for it, but had trouble using them.

Using a multimeter and some paperclips I tested each stage of the flashgun and the synchronised trigger mechanism in the camera and found that each stage of the system worked in isolation, but still no joy taking photographs with a flash. I think some of the connections were a bit loose due to corrosion.

I took the (very simple) flashgun apart and washed all of its copper connectors in spirit vinegar to make them red and shiny again. Most importantly, I found it was necessary to scratch the corrosion off the contacts of each bulb before use, using the handle of a teaspoon or similar.

Now I can enjoy reasonably reliable retro flash photography, using Philips Photoflux PF1b flashbulbs. They’re quite expensive but I bought 15 bulbs from eBay for about a tenner. They’re good fun to simulate “proper” retro photography.

A note to anyone who is old enough to remember this stuff from first time round: Sorry for being so excited about obsolete technology. I’m just discovering this stuff for myself and I think it’s great! :D

Categories: Photography Tags: , , , ,

“I’m just…”

August 1st, 2010 No comments

If there’s one phrase I hate, it’s any phrase starting with “I’m just…”. Worse yet, “But I’m just…”.

It particularly annoys me how many people think that using a phrase including the word just is sufficient to get around rules, or to allow for special dispensation.

“I’m sorry, you’re not allowed to use your phone in here.”
“But I’m just calling someone.”

“Can you call me back later? I’m a bit busy right now.”
“But I just wanted to say…”

The same rules apply to all of us in most circumstances. If I can obey convention by not using my phone in the library, not pestering people when they are busy, and not breaking the rules of the road when it suits me, why can’t everyone else?

I would like to conclude this blog post in the same way my mother used to cut short my childhood whines.

“But I just…”
“But nothing.”

</rant>

Categories: Rant Tags: , ,