Electrified Tea Leaves

So a few days ago I set you all a Mystery Object of the Week quiz, well today is the big reveal.

While there were some interesting guesses (thanks Adrian), no one got it right. It is in fact a static grass applicator -- an example of the grass can be seen to the left, and I've blogged about static grass in more detail on my railway modelling blog.

Essentially this specific applicator is the handle and electronics from a fly swatter with the swatting bit replaced by a tea strainer and a crocodile clip on the end of a wire. (it's easy to build although I bought mine from eBay) Pressing the button causes a static field to be setup between the tea strainer and the crocodile clip so when the grass fibres fall out of the tea strainer they align vertically to produce the grass. What you don't want to do, however, is let the crocodile clip and the tea strainer touch as the rather large amount of stored electricity, that would normally be used to kill a fly, gets released with a bang and a flash of light -- certainly something you don't want to get too close to!

Mystery Object Of The Week

It's been a while since I last did a mystery object of the week quiz (see here for the the previous objects) but I thought it might make a nice change from recent posts.

As before feel free to leave your guesses in the comments and in a few days I'll post the answer. Happy guessing!

Grasmere

As I mentioned in the previous post, last weekend we spent a few days away staying in Grasmere in the Lake District. While we did have quite a bit of wet weather we were lucky in that we did manage a single dry day for a nice walk around Grasmere; the lake not the village.

At the south end of Grasmere you can easily get right down to the waters edge, which seemed the perfect place to play with automatic panorama option on the new camera. I'm not sure if the quality is quite as good as when manually stitching the photos together (you can take a lot more photos that way), but it certainly is much easier and quicker, with the advantage of instantly knowing if it worked or not.

Over The Road And Far Away

Last weekend we managed to have a short holiday in the Lake District (we stayed in Grasmere and there will likely be more post covering the actual holiday) which as well as being an excellent break from work meant we got to test out the new camera I talked about in the previous post.

After three days of heavy use we are both extremely happy with the camera, although there are still a bunch of features we haven't played with yet. The photo I picked to illustrate this post shows off the x30 optical zoom quite well. We heard the woodpecker well before I managed to spot him on the other side of the road a few yards into a small woodland. Not only did the zoom allow me to get a decent shot but the auto-focus didn't get too confused by all the overlapping branches either. And the GPS co-ordinates embedded in the photo are as accurate as you could hope for (within the 30m accuracy figure often quoted for commercial GPS systems).

All in all I'm happy enough with the camera that I'd certainly recommend it to other people.

Bells And Whistles

After eight years and almost 30,000 photos our main digital camera, a Sony DSC-F828, has finally died. It had been suffering for a while from randomly misbehaving pixels, but the more recent problems are rather more fatal. It will still take photos but only if you don't try zooming in. Once you get past a zoom level of x3 (which isn't really very much) then pressing the shutter doesn't result in any mechanical sounds and the photo is highly over exposed. If you turn the camera on when zoomed in then you can feel the motor inside the lens buzzing rather than doing anything useful. So while I might continue to use it for close up macro work (especially given that I own a macro lens adaptor for it) it isn't going to see much use.

Given that we've had no problems (until recently) with the Sony camera and have found it easy to use we have replaced it with another Sony bridge camera; specifically the DSC-HX200V. This camera, while costing half what the old one cost, has a x30 optical zoom compared with x7 and an 18 megapixel sensor compared to the 8 megapixel sensor in the old camera. It's the number of new features though that amazes me, and these are just the ones I've found so far:

• sweep panorama
• 3D still images
• 3D panoramas
• HDR still images
• tracking focus
• background defocus
• face/smile detection
• GPS tagging

I'm assuming that some of these are more of a gimmick than truly useful (I don't see how you can do true 3D photography with a single non-moving lens), but others, like the GPS (which will mean I don't need to carry my GPS track logger around), might turn out to be really useful. It is also supposed to support full HD quality video recording, although any video recording would be better than that supported by the DSC-F828 (very poor quality VGA resolution), so I might start doing some video work as well.

So far it looks like a really good replacement for the old camera, what we need now is a holiday to give it a really good test!

Blink And Remeber It Wholesale

If you've been reading this blog for a while you may well remember that while I'm in favour of bundling digital copies of movies with a DVD purchase, I haven't always found the experience to be particularly enjoyable. Recently though I've been very impressed with Tesco's blinkbox service.

While blinkbox is mainly aimed at the digital distribution of movies and TV shows (you can rent or buy digital copies of most of their offerings) I haven't actually paid them any money directly. My only contact with blinkbox has been the checkout at my local Tesco store.

Basically if you buy a supported DVD (one that is also available through blinkbox) in Tesco they give you access to a free digital copy through blinkbox as well. If you use your club card when paying then you will find an e-mail waiting for you when you get home reminding you about the digital copy, otherwise you'll find there is a code on your receipt that gives you access. The first time I came across this was when I picked up a copy of the new Total Recall film (which is actually pretty good, and which explains the title of this post) but I've had the same experience with quite a few other films now as well. I've only tried watching these digital copies on my computer (it even seems to work under Ubuntu although it isn't listed as supported) but blinkbox supports a whole range of devices from computers, to TVs, consoles, and various set-top boxes.

Amazon are doing something similar in the US with CDs which they call AutoRip, where if you buy a supported CD you will instantly get access to an MP3 copy of the CD to listen to while you wait for the physical version to arrive. This sounds like a really useful service which I hope they extend to the UK at some point.

While I think both services are a great idea I can see one small wrinkle; copyright law. Both services are essentially providing you with a digital copy when you buy a physical copy, not purely to make your life easier, but to move people away from performing format shifting themselves. The digital copies these services provided can't be easily shared (either they use DRM to lock them to your account or watermarking to make them easily traceable) and the hope is that if they provide the flexibility of a digital copy you won't need to create and share an untraceable copy. That is all well and good, but what about if you buy a DVD from Tesco (or a CD from Amazon) as a gift? If you give away the physical copy do you still have the legal right to watch the digital copy? I would assume that you don't although I can't find any details in the terms and conditions. Usually the assumption is that you can format shift for personal use, but if you get rid of the original copy then you must get rid of the copies you made as well (i.e. you can't rip your CDs to MP3 files and then sell the CDs while keeping the copies). I would assume the same legal restrictions would apply to blinkbox and AutoRip. One day copyright law might catch up with the modern world and answer such questions.

Cold Storage

Over the years I've had quite a few hard drives fail on me. Fortunately, most of the time they've failed gracefully allowing me a short window in which I've been able to rescue their contents. In other words I've been exceedingly lucky not to have lost anything important, especially as I'm not particularly good at taking regular backups. The one thing I do tend to backup quite well are the digital photos we take.

My photo backup routine is simple. Firstly the photos end up on both my computer and Bryony's so we each have a separate copy. I also burn all the photos to two DVDs. One DVD I keep in the house and the other I periodically ship off to my parents for an off site backup. The off site backup is probably the most important, as while the copies in the house allow me to recover easily from a hard disk failure they don't insure me against a catastrophic incident at the house; fire, flood etc. Unfortunately DVD-R disks (and this also applies to CD-Rs) don't last forever.

As I've mentioned before we are trying to have a good go at tidying the house and getting rid of things we really don't need. Over the last 15 years or so I've burnt probably thousands of CD-Rs and DVD-Rs and most of the data on them is no longer need -- a lot of them contain installers for old versions of software or backups that have since been superseded by newer backups etc. Before throwing any of these disks away though I need to go through each one to check what was on them. So far I've managed to amalgamate around 50 DVD and CDs down into a single DVD, which is quite a good space saving. Unfortunately this hasn't been quite as easy as I'd expected as some of the disks had developed bit rot. Fortunately, with the help of ddrescue, I managed to extract everything I wanted from the damaged disks.

Some of the damaged disks I had to process were only around five years old and if they had been left much longer may not have been readable at all. Now while I've never bought the most expensive of blank CD-Rs or DVD-Rs I had expected that they would last for more than five years. Clearly if I want to ensure that my digital photos are still safe in ten or twenty years, as well as for future generations, then relying on DVD-Rs as the final backup probably isn't very wise. The solution, I think, is cold storage.

As I mentioned recently I've just started work on a new project called ForgetIT. ForgetIT, is essentially, an archiving project, with the interesting research focusing on incorporating human inspired models of memory and forgetting to ensure that we archive enough extra content to make the information understandable years after it was archived. In discussion one thing that kept being raised was where we intend to archive data to, and of course the current buzz word is The Cloud. While there are many possible online storage solutions (Google Drive and Dropbox being two popular services) they can all start to become expensive quickly. For example, with Google Drive you can store 5GB for free, but then an extra 25GB will cost you $2.49 a month and I've already got approximately 100GB of photos I want to store. These services are also designed around frequent and fast access; they are designed to act as a remote hard drive. This can be useful for syncing files across devices, but isn't necessary for long term archival storage. Cold storage takes a different approach to storage.

The idea behind cold storage is that it is for data you will want to access very infrequently, if ever. This approach allows service providers to take a different hardware approach (possibly turning off hard drives when they aren't needed or using tapes). This allows the cost to be reduced at the expense of access times. I think cold storage is perfect for the backup of last resort for photos as hopefully I'll never need to access them and if I do I won't need instantaneous access. I can also see this form of archiving being useful to companies for auditing or legal purposes where documents have to be be kept for a number of years but may never actually be requested.

Last year Amazon started to offer a cold storage service called Glacier. The headline information is that storage costs are just $0.01 per GB per month but that retrieval requests take four hours before you can start downloading your data. This means that I can store my current 100GB of photos for just $12 a year, and should I ever need to access them I won't mind a four hour wait. Before you all start rushing to copy your backups to Glacier there are a couple of points I've glossed over that need raising.

Firstly Glacier is part of the Amazon Web Servies (AWS) framework. AWS is a set of web services designed for developers and as such Glacier doesn't have an Amazon provided end user interface of any sort. Fortunately a number of people have started building applications. Some are command line tools which are great for scripted backup solutions, but there are also a few graphical interfaces. I've discussed these in more detail over on one of my other blogs where I'm currently recommending SAGU (Simple Amazon Glacier Uploader) although I'm also developing an application which I'm calling CORPSE (or COld stoRage backuP SoftwarE).

The more important issue is the cost. While the headline price of $0.01 per GB per month is certainly enticing it's worth noting that you are also charged for retrievals (although not for uploads). Firstly there is a per GB cost for transferring data out of Amazons servers (this is a standard AWS data out charge) which is free for the first GB each month but is then charged at $0.120 per GB (assuming you retrieve less than 10TB). This cost is at least easy to calculate. The more worrying cost is for the retrieval.

The retrieval pricing structure is really quite complex. Essentially "you can retrieve up to 5% of your data stored in Glacier for free each month ... [which] is calculated and metered on a daily prorated basis. For example, if on a given day you have 12 terabytes of data stored in Glacier, you can retrieve up to 20.5 gigabytes of data for free that day (12 terabytes x 5% / 30 days = 20.5 gigabytes, assuming it is a 30 day month)." This means, of course, that if you are willing to spread your retrieval out over a number of days/weeks/months/years then you can retrieve as much as you want without paying a retrieval fee. If you need your data quicker though then you will pay for the retrieval.

Calculating the amount you pay is complicated and I can't really summarise it without simply reproducing Amazon's examples so I suggest you go and read the details they have given. Their examples can, however, be summarised in a table. Essentially assume you have stored 75TB of data, so you're daily free limit is 128GB, and you want to retrieve 140GB. Depending how you spread out the retrieval changes how much you pay, as follows:

Hours	Peak Retrieval Rate	Peak Billable Retrieval Rate	Cost
4	35GB per hour	3GB per hour	$21.60
8	17.5GB per hour	1.5GB per hour	$10.80
28	within your daily allowance		$0.00

As you can see, as you spread out the retrieval over time the price drops to the point at which the cost for retrieval becomes $0. The problem is going to be keeping track of your downloads over time in order to try and estimate what a retrieval will cost. The best calculator I've found for this so far is unfortunately unofficial but seems to match up with Amazon's examples so should be a good starting point for estimating your costs. Of course my use of Glacier is predicated on the fact that I'm hopping never to need to access the data as it is the backup of last resort.

Even if you don't like the idea of cold storage, or Amazon's pricing structure, then I hope that this blog post will at least have made you think about when you last took a backup of any data you wouldn't want to lose and, more importantly, how long those backups are going to last for.