Have you ever been out and about with your DSLR and wished that the lens that you had fitted could zoom in just a little more? That extra reach can be handy in many situations – but for most of us a new lens is out of our budget – so what’s a photographer to do?
One solution to the problem is to consider getting yourself a teleconverter for your lens. Teleconverters (sometimes called extenders or multipliers) are generally much cheaper than a new lens and can multiply the focal length of your lens by anything from 1.4 times to 2 times.
In this tutorial I’ll explore some of the pros and cons of teleconverters.
I’d previously used this lens at similar events and while it produced some wonderful results it left me thirsting for more focal length to get even more closely framed shots of players.
Canon make two teleconverters for DSLRs – the 1.4x and 2x versions (and other manufacturers make similar models – for example Nikon’s 2x, 1.7x and 1.4x). Keep in mind that extenders don’t work with all lenses. You should check with your manufacturer before purchasing to see if you own compatible lenses. I’ll profile a few more teleconverters below.
The Pros of Tele-converters/Extenders
Focal Length – The obvious benefit of using a teleconverter on your camera is that it extends the effective focal length of whatever lens you use it with. A 1.4x converter will give you an extra 40% (extending my 200mm maximum to 280mm) and a 2x converter will give you a 100% boost (effectively giving me a 140-400mm zoom.
The benefits of this extra reach are obvious – it could turn the framing of a tennis player shot from court side from a full body shot to a tightly framed upper body shot which reveals rippling muscles, dripping sweat and the grimace of their face as they strike the ball….
Cost – In comparison to the cost of buying a 400mm lens a teleconverter is a much more economical way to go.
Weight – I don’t know if you’ve seen some of the longer lenses going around but they can be quite huge. Add a 2x extender to a smaller lens instead of getting one of the larger ones and you’ll save your back some hardship.
Minimum Focus Distance – using an extender means you can keep the minimum focus length of your lens. This can be handy when you don’t have a macro lens handy and want to get close in on a subject that isn’t far away. It won’t really compare to a dedicated macro lens – but can be handy.
The Cons of Tele-converters/Extenders
So why wouldn’t you rush out and buy a teleconverter?
There are a couple of costs (in addition to the monetary one) associated with them.
Lens Speed – The first thing to consider when using a teleconverter is the impact it has upon how much light gets into your camera.
Using teleconverters means less light gets in which means your maximum aperture will be decreased. When using a 1.4x converter this means you’ll lose one stop and when using a 2x converter you’ll lose two stops (It was for this reason that I went for a 1.4x teleconverter instead of the 2x one as I didn’t want to slow my lens down any further than f/5.6).
So last year at the tennis, instead of being able to shoot at f/4 with my camera I had a maximum aperture of f/5.6.
I was lucky that the weather was excellent on the day and there was plenty of light so this didn’t really impact my shots too much – however if you’re shooting in low light or indoors you’ll notice the impact of this more.
Camera Shake – As you extend the focal length of a lens – any movement of your camera will become more noticeable.
Using a teleconverter magnifies both your subject and any movement in your camera so you’ll want to think carefully about how to reduce it, either by increasing your shutter speed and/or using a tripod/monopod or some other technique to secure your camera.
Focusing Speed – Another consideration with tele-converters is that they slow down the speed at which your camera will focus. This will vary from lens to lens but is particularly an issue in lower light. Some lower end DSLRs will not be able to use Auto focusing at all with some teleconverters at certain aperture settings (or at all) – so do check your camera’s compatibility before buying. To get around slow focusing switch to manual focus mode and learn how to use it – you’ll be surprised how quickly you get the hang of doing it yourself – it’s a useful skill to have.
Image Degradation – Extenders multiply not only the focal length but also any aberrations of the lens you pair it with. As a result you’ll notice on many lenses that image quality suffers – I’m told this is particularly the case with longer extenders (x2) where sharpness and contrast suffer – particularly when shooting into light (where flare and ghosting can be a problem). Using the best quality lens possible will help keep such degradation to a minimum.
Using extenders/tele-converters is a more affordable way to extend your focal length than to purchase a longer lens – however the cost can be to your image quality and camera performance if you are not working with a high quality lens in decent light.
I think they are well worth using if you need the extra reach but wouldn’t use them for every shot. I definitely travel with my 1.4x extender at all times when shooting with my 70-200mm lens.
When using one try not to use them at the maximum aperture that your camera will allow – but stop it down at least one stop and you’ll find the results are significantly better. Also keep in mind that longer focal lengths will leave you with less depth of field to play with – so your focusing needs to be spot on!
Teleconverters vs Cropping
Of course the alternative to using a teleconverter or extender is to take your images with what ever lens you have and then to crop those images later in your post production phase. This is definitely the cheaper option – however in my own testing I’ve seen better results with a teleconverter. You can get away with cropping – but if you want to really blow up your images a lot the converter will be an option to consider.
Teleconverters to Consider
Canon Extender EX 1.4x II – the one I use and love. It’s not cheap when compared to some other manufacturers but does a good job. Works best when you don’t push it to the maximum aperture (pull back a stop and it produces some nice results).
Canon Extender EX 2x II – double your lens focal length with this one. Doesn’t work with all lenses and I’ve heard it can produce slightly ‘soft’ results.
Nikon AF-S TC-14E II 1.4x – I have friends with this one and the results they get are excellent. Not compatible with all Nikon lenses – but where it is it’s a great little extender – although not cheap!
Sigma 1.4x EX DG (pictured right) – I hear a lot of positive things about this 1.4x extender. Sigma make them for all the major DSLR manufacturers and they are compatible with many lenses (check first though). It works best with a smaller aperture than wide open but for it’s price it looks like one to consider. You can get it for Canon, Nikon, Pentax and Minolta and Sony lenses.
Sigma 2x EX DG – another sigma option which also gets good results by all reports. Sigma again make it for all the major manufacturers including – Canon, Minolta and Sony, Nikon, Sigma, Pentax lenses.
Feel free to leave your own recommendations and experiences of Teleconverters and extenders below.