Thursday, 12 July 2012

Amazon Kindle: One of the Best Tools in a Technical Pro's Arsenal

As any professional knows, you can't get by in technology without constantly keeping your skills up to date with emergent technologies. Of the various ways to do this, one of the best is to choose some detailed technical books in those fields that are presently of interest. Preferably ones that have been written by people that are actual hands-on developers themselves, rather than those by authors that merely have an academic interest in the subject under discussion. Wrox Press does an excellent line of books called Programmer to Programmer, which are very useful in this regard.

Once you've absorbed the material, and have used the technologies concerned on a few live projects, these books become an excellent source of reference material, which you can refer back to time and time again. If you're anything like me, you'll have a bookshelf at home that looks something like this:

RP's old technical library

The only downside to Wrox books (and any other type of reference manual) is their weight. It's typically handy to have those books that are relevant to the discrete areas you're working in at a given time to hand as you tackle a real project. Given that even a few books combined generally weigh around 2-3kg, that can be a real strain on your back, especially if you're already carrying a laptop and other bits and pieces around too. 

Around about two years ago, I bought an Amazon Kindle, for the express purpose of carrying around these tomes without dislocating my spine. The passive e-ink display of the basic Kindle device is great for reading in bright sunlight:

Physical Kindle Device

And there's a handy little management tool on the Amazon website that allows you to keep your books safe and available at all times, wherever you may be:

Amazon's "Manage Your Kindle" tool
(View full size here)

The battery on a physical Kindle device lasts for a very long time (at least a month of continual use between charges), and the device itself has room for loads and loads of books. There's also a free PC-for-Kindle application that allows you to view the e-books you've purchased on any PC. And for Android users, there's a nifty free Kindle-for-Android app that allows you to view your books on your tablet:

Kindle for Android tablet, Library View
 or on your Android phone:

Kindle for Android phone
These latter applications are particularly useful if a book you happen to be using utilises colour to convey meaning:

Colour-Coded Keywords
Coloured Graphics
                    (View full size)                                                  (View full size)

However, the best thing about using Kindle as your technical library, which all technical departments should take heed of, is that you need only buy each book once. If you've got a department full of 20 developers (within which there will undoubtedly be a huge overlap of skillsets), it makes sense to buy one copy of each book, and allow each developer access to that library of virtual books via their own PC. An organisation that wants to make effective use of technology will also probably find it profitable to fork out for a few Tablets and physical Kindle devices for taking into meetings. In terms of increased profitability for individual developers, they'll pay for themselves in no time.

Wednesday, 11 April 2012

Academia: The Internet, You're Doing It Wrong.

There was an interesting article on Radio 4's Today programme yesterday, concerning the way peer-reviewed research journals such as Science and Nature charge British Universities hundreds of millions of pounds each year for access to the scientific research they publish on academics' behalves. In many cases, in a bizarre reversal of the normal economics of the process of publication, these journals also both charge the publishers of the research themselves for the act of publishing, and require those authors to sign away copyright to the journals involved so the originators of the work can't even reproduce their own articles elsewhere (hence the fees – to the publisher, not to the author - when other academics later want to see what's been written by their peers).

The wider piece centred around a new website that's about to be launched, called eLife. The project is being championed by Sir Mark Walport, the director of the Wellcome Trust, and aims to provide a free, centralised place for research to be published instead.

The whole piece got me thinking about how Universities, and for that matter most publicly-funded bodies, don't seem to use information technology at all well, most particularly the web. The apparent benefits of peer-reviewed publications, at least in the eyes of those academics that choose to publish their work through them, is that they allow other academics in their fields an easy way to find and review their research. This apparently enables them to collaborate better and promotes further scientific development. Because, you know, unless publications like Nature et al existed, academic research would be otherwise impossible to publicise, find and share. 

If only there were an effective way to search the internet using some sort of tool – kind of like an engine for searching, if you will – that could enable academics to allow their work to be discovered that way instead? And wouldn't it also be nice if there were some existing, free, centralised, widely-respected encyclopaedia of knowledge, that was editable by anyone, and that was well-indexed by these 'search engines'. In an ideal world we could even make that online encyclopaedia itself searchable in its own right. In such a technological Nirvana, academics of all flavours could easily just publish their own original research on their own blogs, within their own institutions' websites, whenever they liked for little to no cost, retain the copyright themselves, then provide an entry in that centralised encyclopaedia of knowledge containing links to their own independently-published research. That way anyone, including other academics, could then subsequently easily find and develop their ideas.

But no, I can't see us having that sort of technology until at least the next millennium, so I guess Universities will just have to keep handing over millions of their tuition fees and state research funding money to journals that provide a shadow of the above service for a fee instead. And who then also charge anyone that wants to read it too.

Monday, 9 April 2012

Update: Loftek Sentinel D1 Review

Despite the Loftek Sentinel D1 CCTV camera that I reviewed recently performing well when first installed, I regret to report that it unfortunately developed a fault within 2 days of installation, ultimately necessitating my returning the unit for a refund.

The fault manifested itself by the camera stopping working during a pan movement on day 2 of operation. I had thought perhaps that it might be a temporary fault that could be easily rectified. Being a professional geek, I tried all of the obvious solutions before concluding the problem was with the unit itself:

1)     Resetting the unit, both using the power supply itself and the reset button on the cable bundle.

2)     Hard-wiring a connection to the camera to check if it'd lost network configuration settings somehow (it hadn't).

3)     Checking whether my router's signal had for some reason stopped reaching the location of the camera (located only 10m from the router, on the outside of my property). Both my mobile phone and my laptop could 'see' my router from the camera's location without difficulty, leading me to conclude that the problem was definitely with the camera's own ability to communicate over that distance, rather than being a problem with the router itself.

4)     Despite the fact that (3) above tended to rule out any problem with the router's signal, I tried alternative channels on the router, including auto-channel select (which should find the best available channel), with no success.

5)     Bringing my router out to my garage, less than 1 metre from the camera, did cause the camera to begin being able to transmit on the network once again. This conclusively proved that the problem wasn't with the configuration settings, power to the camera or a mechanical issue with the camera, but was definitively a camera to router signal propagation issue. [If it had been a router to camera propagation issue, then my other wireless devices wouldn't have been able to communicate from the camera's location whilst the router was in its usual indoor position. Also, it was clearly a fault that had developed, rather than simply being a characteristic of the camera, since the camera itself had been able to communicate with my router in its indoor location for the initial 48 hours after first installation.] Unfortunately, I couldn't leave my router outside in the garage just to allow the camera to work over a much shorter distance, as it would then be out of range of my hard-wired internet connection, negating the purpose of having a wireless camera in the first place.

I contacted Loftek to give them a fair chance to recommend a fix to the problem. Unfortunately, their technical advice appeared limited to suggestions that frankly I could have got by watching an old episode of The IT Crowd. They said to try changing the router's channel (I hadn't told them that I'd already tried that, but I had explained in my e-mail that other wireless devices could connect to my router over the same distance, which should have ruled out frequency interference as a possibility). In their only other suggestion, they actually used the phrase "try switching the camera off and back on again". Really, any techie that still gives the old "try switching it off and on again" advice to someone that's demonstrated they're reasonably technically proficient should be deeply, deeply embarrassed. 

So, with regret, my ultimate conclusion about the Loftek Sentinel D1 is that it was a good idea, but the unit itself is so unreliable as to make it unworkable in practice. Going by the mass of traffic to my blog with search terms such as "Loftek Sentinel D1 wireless doesn't work" since posting my review, I'm guessing I'm not the only one that's experienced difficulty.

Good luck, dear readers, with your own technical woes. I hope you have better luck making this product work than I did. If not, try switching it off and.......never mind.

Sunday, 8 April 2012

Product Review: Loftek Sentinel D1 CCTV camera

This is a product review for the Loftek Sentinel D1 CCTV security camera that I installed at home recently, available in the UK for £115 from Amazon.

NB: Please read the post below in conjunction with my subsequent update to this review.


I chose this particular camera because I wanted a more subtle method of security for my property than a more in-your-face CCTV system could have provided. The dome design on this model means that it can easily pass for a light fitting, and is therefore not too obtrusive, thereby allowing me to beef up security in a subtle but effective way, without making my home feel like Fort Knox. Other more overt camera systems may provide a greater degree of visible deterrence to vandals and thieves, if that's what you're looking for, but for a home setting in a quiet residential area that you want to remain welcoming, this felt like the right choice.
Wos this?
On the technical front, being a geek by profession, I found no difficulty in getting this item set up within minutes of opening the box. It was merely a matter of attaching the camera to my wired network (via a LAN port on my wireless router) in the first instance, then you have the option of either installing the enclosed IP Camera software to obtain the device's IP address, or simply use your router management software to identify the IP address that your home network has assigned to the camera. After that, just use any popular browser (Firefox worked for me, and I tested IE9 too) to navigate to the camera's setup page, by typing the camera's IP address into the browser.


tinyCam for Android running on an ASUS Transformer tablet PC

...and on an Android phone

Screen dump of the browser-based configuration utility

The home page guides you to install some third party software from VLC to view and control the actual camera feed, and you're off. Finally, use the camera's web-based configuration utility to provide the device with your wireless network settings. After that you can dispense with the wired connection, which you wont need again. I found that the camera retained wireless configuration settings, even when switched off during the actual installation process. So, once set up, the device seems to be pretty stable to issues like power cuts that might otherwise have been a problem for a less well thought out design. I also tested accessing the camera using my Android tablet, and found that to be very easy too. There's a free app called tinyCam monitor that does the job. There are also other applications for a modest fee (typically less than £5) that purport to enable you to store images online or on your device's SD card, based on real time rolling imagery or on motion-sensitive images. I haven't tested any of these capabilities, and therefore can't comment on whether this model or the Android apps mentioned work for these purposes. 

My installation
With regard to the hardware itself, the only slightly-misleading thing for me was the fact that the unit requires a wireless antenna, which screws into the side of the camera itself rather than being located in a more subtle location such as at the cabling terminus. This isn't shown in the product photographs provided. If you look at the manufacturer's images, there's a little gold protrusion shown, that looks like the end of a screw that goes right through the bracket holding the unit. 
Manufacturer's image, with antenna missing
That's not actually a screw, though: it's the connector for the antenna, which isn't shown, and which is about 7 inches in length when fitted. This reduces the visual appeal of the device, by making it more obvious that it's a camera. There is still the option of connecting a wireless access point to the cabling terminus of the device (which is hidden away near the power supply), but still, it'd have been nice to see the product as it really appears, rather than having visual details like this being left off of the product photos.

Having read some of the other reviews available online for this item, I had been a little worried that I might experience some issues with autofocus whilst panning to areas at different focal lengths (some of the American reviewers referenced above had indicated that they'd had difficulty in this regard, and had been instructed by the retailer to adjust the focus manually by removing the camera's cover and using a screwdriver). However, I needn't have worried, as I simply didn't experience this issue. If this were ever a problem, the current model doesn't appear to suffer from it.

The low light facility on this camera is pretty damn impressive. It's not an infrared camera, and that's not what I'd decided upon for this particular installation, preferring instead to rely on visible lighting around my property. The first day after I installed the camera, though, I was in the position of still having to replace some external lighting that had failed over time (job now done, though it took an angle grinder and a lot of sparks to remove one of the old light fittings - apologies to any of my neighbours disturbed by the brief but wrenching noise of that process!). Because I had a day of darkness before I replaced that broken external lighting, I inadvertently had the opportunity to see how the camera performed in near-complete darkness. Under those conditions, I could still make out a reasonable amount of detail and colour, just from the ambient light provided by a streetlight across the road (see the sample photos below for a comparison of daylight, full dark, and moderately lit nighttime camera images). I felt that the 'moderately lit by a 60W door light' images were quite good enough for my purposes, negating the need for a camera with full night vision capabilities that I had been considering as an alternative.

Lit by one 60W bulb
Complete Darkness

Lastly, I'd say this model is a good option for securing your own property, whilst respecting the privacy of your neighbours. I can see everything I need to see on my own property. However, the fact that the camera is limited to a moderate 3x zoom means that whilst it's more than enough to identify callers at the front door, the view it necessarily gives of any public areas and neighbouring houses actually has less resolution than the view I can get from looking out of my own front window or walking down the public street. I see this as a good thing. Some of the cameras I reviewed before deciding upon this item were way too highly-powered for a residential area, offering up to 22x magnification in some cases; it'd be hard to justify the need for that sort of resolution outside an industrial setting.

Overall: I think this an excellent camera, at a reasonable price that represents good value for money, and that's not too hard to set up. I'd recommend it for use in a domestic setting, especially for areas where fixed cabling may be an issue, provided you don't require true night vision for your specific purposes.

Monday, 6 February 2012

Silverlight Data Binding: A comparison of INotifyPropertyChanged and DependencyObject.

NB: Owing to YouTube's policy of trying to force Google+ on YouTube members, I no
        longer host content on YouTube. Apologies for the inconvenience.

The project I worked on most recently involved using Silverlight 4 in conjunction with Prism and MEF. This entry is a brief tutorial on one of the core concepts in Silverlight : data binding, which can be achieved in two main ways, each with benefits specific to the contexts in which they're best suited.