Your new XSi – The Kit Lens

This is a short article for a flickr friend (you know who you are) about the Canon EFs 18-55mm 3.5-5.6 IS. First off, a lot of people will bad mouth this lens. Ignore them. It is a good lens. It can be very sharp. It has IS, good for up to 4 stops! There are some problems, but for an entry  level lens it is quite good.

First, the zoom range. 18-55mm. This is a good normal zoom. Wide enough for landscapes and narrow enough for portraits. One length you want to look at is 35mm. At this zoom the field of view is close to what you see with your own eyes.  Another thing is at 35mm f5.6 this lens is at it’s best. As sharp as it gets, no distortion, very low CA and no vignetting. Also if you are shooting in low light, at 35mm with the IS turned on you should be able to shoot down to 1/6 second with no camera shake!

Things to look out for. The lens does have a pronounced barrel distortion at 18mm, greatly reduced at 24mm. At the wide end there is some vignetting at f3.5 but stopping down to f5.6 removes it. (can also be fixed in DPP) Another thing to look out for is a strong CA (chromatic aberrations), especially at the edges. Stoping down helps but avoid high contrast spots.

The lens continues to get sharper till it hits 35mm the starts to drop off. 55mm is the softest. Stoping down to f11 will help but it will not be nearly as sharp as 35mm. The CA’s also jump at 55mm at the edges. There is also a little pin cushioning at 55mm, but nothing really noticeable.

What are CAs? Blue fringing on high contrast areas. Technical link to Wikipedia. You can correct it in DPP (Digital Photo Pro) that came with your Canon EOS.

Where did I get this info? Mostly from personal experience but also from DPReview and The Digital Picture.