Canon lenses?

George.d(^^,)b

George.d(^^,)b

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Any suggestions on decent zoom lenses for EF / EF-S format? Within £150 price range and also portrait lenses other than the 50 1.8 / 1.4 I don't quite understand the whole MM thing, I've tried, but it seems the 55-250mm has the same range as 400mm - that's what i don't understand..
 
simple answer is it depends on what camera you have. If you have any camera below a 5d (which you prop ably have seeing as your looking at EF-s lens) you have to multiply the focal distance by 1.6. The reason being these cameras do not have what is called a full frame sensor (EF-s does not work on FF bodies only EF lenses do) Wikipedia has a good description and goes into the physics behind this.

The 55-250 is a great lens for the money I used to have one.
 
For less than £150 you really won't beat the 55-250! :clap:
I've been using mine for a few weeks on my 600D and although it can be a little soft at the long end in poor light, overall I can't fault it and I am more than satisfied with it!

This was taken at the 250mm end. :cool:


001-22 by ricrico, on Flickr
 
Thanks for the suggestions! I've had a look and the mark II version of the lens is only £130 on eBay - so will have to invest in that I think! :D
 
If you can find the mark 1 get that instead.
The mark II is just a cosmetic upgrade (matching the 18-55IS II).
 
George.d(^^ said:
Any suggestions on decent zoom lenses for EF / EF-S format? Within £150 price range and also portrait lenses other than the 50 1.8 / 1.4 I don't quite understand the whole MM thing, I've tried, but it seems the 55-250mm has the same range as 400mm - that's what i don't understand..
Click to expand...

Just to pick up on the 250mm / 400mm thing..

In the film days each negative was 35mm wide.
Initially to make a sensor for a digital camera that big was impossible, then as technology advanced it became possible, but flipping expensive.

The answer was to make sensors that are smaller.. the trade off is that overall image quality is not as good.
DSLRs that have a 35mm sensor are known as "full frame".
Cameras with a smaller sensor are known as "crop cameras"
Nicked from wikipedia maybe this will help:

Sensor_sizes_overlaid_inside_-_updated.svg


You'll notice that the Canon APS-C cameras (like yours) have a crop factor of 1.6..

The size of the sensor affects the field of view - probably best to read this : http://en.wikipedia.org/wiki/Crop_factor

So if we take the 250, times it by the crop factor (1.6), we end up with... 400mm. This basically means that a 250mm lens on a 1.6 crop factor camera has the same field of view as a 400mm lens on a full frame camera.

hope that helps ?
 
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