Glidecam 2000 Pro
Handheld video just doesn't cut it on SLRs – they don't have the right handles or enough weight to keep the shot steady. If you want a gliding, cinematic effect you'll need one of these stabilisers to make your video silky smooth and get rid of that distracting wobble. It takes a bit of setting up (there are plenty of Glidecam users offering tips online), but once it's balanced you'll be amazed by the results.
Sooner or later you'll want to make a video that isn't just moody shots of dusky landscapes set to music. When that happens you'll realise that using your camera's internal mic just isn't up to scratch. Clip this external, battery-powered microphone into your camera's hot-shoe, plug the 3.5mm jack in the side, and you'll have clear directional audio that'll make all the difference when filming interviews and events.
Also… for an extra £30 you can add a Rode Deadcat windshield to cut out wind noise
Polaroid 112 LED video light
Dark and moody is great if you're shooting the next fan fiction Batman sequel, but it has to be lit properly in the first place to come out looking right. One of these LED light panels is enough to make sure it doesn't look like you're shooting in the dark end of the Bat Cave. Adjustable brightness and optional barn doors (the flappy bits) make it a versatile addition to your kitbag.
Hoya HRT Circular Polarising UV lens filter
From £34, fotosense.co.uk
Once you screw one of these onto your lens, you'll wonder how you ever did without it. By cutting down reflected light, you'll find it boosts colour saturation (especially in skies and foliage) and lets you shoot subjects behind glass more easily. Not that we want to encourage your voyeuristic tendencies, mind.
Around £220, konovaphoto.com
Sideways movement (tracking) is a great way to make an otherwise dull shot interesting. Korean firm Konova does one of the best value sliders around. Importantly it uses bearings for super smooth motion and has been well received by the budget-conscious SLR video community. It comes in lengths between 80cm and 1.2m, and you can stand it on a flat surface or mount it on a tripod. At the moment you can only get it direct from Konova or on ebay.
Lens adapter for classic prime lenses
around £15, amazon.co.uk
Autofocus zoom lenses made by the likes of Canon and Nikon can be really pricey. If video's your game, play it smart and get an adapter so you can use some great older lenses like the Olympus OM mount Zuiko range. You'll want to use manual focus anyway, and prime (fixed focal length) lenses can be picked up for under £100 on ebay.
Giottos GTMML 3270B Monopod
We're going to assume you already have a tripod, and that it's an awesome one with a fluid head and ball levelling system. But that tripod weighs a ton and you need something light that you can take with you everywhere. This monopod weighs just 700g, collapses to just 54cm long and will give you a stable shooting platform wherever you are. A dedicated monopod head costs as little as 15 quid.
£free, firmware download and wiki
The Canon 5D MkII and 550D were designed primarily to take photos, with video as an afterthought. This means that they don't feature all the handy electronic aids that come with a dedicated camcorder. The cunning Magic Lantern folks have tweaked Canon's firmware to add focus assist, audio metering, exposure tools and more to turn your SLR into a video powerhouse. But BEWARE – updating your camera with unauthorised firmware isn't covered by Canon's warranty and there's the real possibility you could brick your precious camera. Whether the potential gain is worth the risk is up to you. Now also available for 60D and 600D.
Zoom H4N recorder
If sound is really important to you, it's worth going the extra mile and getting a separate audio recorder. This is a more expensive route than the Rode VideoMic, especially because you'll need to buy a microphone and cable to go with it, but opens up a whole new dimension (and level of complexity) when it comes to producing your videos. The 2 XLR inputs and stereo microphones are especially useful.
White balance lens cap
If you don't white balance your camera regularly you could be stuck spending time colour-correcting all your footage unnecessarily. It's a hassle and it's not always easy to find something white to balance from, or someone to hold up a card. Enter the White Balance Lens Cap. Now all you have to do is take a photo with your lens cap on and balance with that. Each cap comes with a neutral and warm colour dome so you can take your pick depending upon what you're shooting.