Nothing can quite match the beguiling attraction of the big-screen. Yes, LCD and plasma TVs are getting bigger and better all the time - take a look at Pioneer's 60-inch beauty the PDP-LX608D or Toshiba's lovely 37-inch 37X3030.

But for true 'home cinema', you've just got to have a projector.

The barriers to projector ownership aren't as high as they used to be. There are plenty of home projector options these days. For every £5K Optoma ThemeScene HD81, new and second hand models can be picked up on the cheap, some for as little as £300.

Modern projectors are also versatile. They'll plug straight into a DVD player or a PC, giving you an instant BIG screen that you can measure in feet rather than inches. Feeling lazy? Optoma's DV11 combines a DVD player and a projector to make things even simpler.

Projectors 101

When looking for a projector there are five important attributes to look for: its brightness (lumens), contrast ratio, noise, resolution and aspect ratio.

For home cinema use brightness is probably the least crucial as, more often that not, you'll be watching films in a darkened room. Ensure your projector is at least 1,000 lumens and not much more than 2,000 lumens; more than this and it'll actually be too bright for your living room.

Instead, contrast ratio is the crucial factor. This measures how well a display - not just a projector - generates light and dark colours. The bigger the ratio the purer and deeper the blacks are, and the richer the bright colours will look.

A projector with a low contrast ratio - anything that sinks below 800:1 - will start to show washed out dark colours and muddy blacks. Many older LCD projectors can have ratios as low as 300:1 and these should be avoided.

The art of noise

Audible noise is the natural enemy of the projector. As you can imagine, having a bulb burning as hot as the sun, trapped inside a tiny plastic box, is a recipe for a meltdown.

While adding a huge fan fixes the problem, it's not very easy on the ears. So a projector that delivers a decibel level of less than 30dB is ideal. Less than 34dB is acceptable, but anything over this will be distracting, even for loud sections of a film.

Then there's resolution. High definition is all the rage these days, but if you don't have any high definition content, or access to any HD channels, then it's a somewhat irrelevant option. An SVGA projector, with an 800 x 600 resolution, is the minimum requirement for watching DVDs and standard def TV programmes.

Of course, we don't think you should seriously consider the SVGA option. XGA projectors with 1,024 x 768 resolutions are everywhere at the budget end of the projector market. Consider these as "fake HD" models.

Considering a 1280 x 720 display contains 921,600 pixels, a widescreen XGA movie will use around 579,584 of the available pixels, significantly better than the 354,400 viewable via an SVGA display.

4:3 vs. 16:9

All of which leads us to the aspect ratio. Most budget projectors - of the SVGA and XGA variety - have 4:3 aspect ratio dispays. The newer HD projectors use a 16:9 ratio, which obviously makes far better use of the available display and is ideal for movies and gaming.

And finally, I'm often asked whether an LCD projector is better than a DLP projector. Whilst DLP projectors on the face of it have far better contrast ratios, they do suffer from the 'rainbow effect', a colour shimmer that can sometimes be seen along bright edges in dark scenes.

Some people see the rainbow effect more readily than others and once you've spotted it you'll find it difficult to ignore. The effect is linked to the speed rating of the projector's colour wheel and a 4x rating is really the minimum to look for.

Best buy options

You don't have to spend big money on a projector. While many of the models in our recent Top 10 HD Projectors article cost thousands, there's now a gaggle of projector options for less than £500. Failing that, there are lots of second-hand options up for grabs on the likes of eBay.

Here are my current top online favourites:

Optoma DS302
At sub-£300, this bargain 800 x 600 DLP projector offers a 2000:1 contrast ratio from a tiny 1.9Kg unit. It also runs whisper-quiet at 27dB. As a budget DLP unit though, you should expect some rainbow effect.

BenQ MP620c
If you want the extra resolution of an XGA projector, this £440 BenQ model fits the bill perfectly. The contrast ratio isn't as high as we'd like (it's only 700:1 and, yes, that breaks the 'not below 800:1 rule I mentioned earlier), but it it is exceedingly quiet and offers both component and DVI inputs.

Optoma HD720X
Available exclusively on the web for under £500, this has to be the lowest cost HD-ready (1,280 x 720) projector we've seen on the market. Similar to the luscious Optoma HD70 - but with a reduced 2000:1 contrast ratio - this represents a great HD buy and an HDMI input.