ef17-40mm f/4L USM Canon

Dryfly · Jul 13, 2008

Hi i have just bought a canon 40D body only and am about to invest in a lens.

I am looking at a lens for landscape photography and was recommended the ef17-40mm f/4L USM, can someone please explain what all that means?? I am new and I am sorry but it does not mean anythhing to me.

ef ? 17-40mm ? f/4 ? L ? (why is it red?) USM ?

is it a "fast" lens? and what is the zoom?

any help would be gratefully appreciated and I would like to understand it before I buy it and will it be fine for landscape as recommended?

thank you.

reg · Jul 13, 2008

EF is the lens mount.

17-40 is the zoom.

f/4 is the maximum aperture.

L originally stood for "aspherical" *well, really, early in the EOS timeline it was AL, then just aspherical, then the aspherical ones became called L. Now it's generally understood to mean "luxury".

USM = UltraSonic Motor

It's not terribly fast, but it's not horribly slow either, for a wide angle lens.

You should really read up on the BASICS of photography before you buy that lens, though. You don't need L glass if you don't know what f/4 means.

Dryfly · Jul 13, 2008

and I supose you probably think I should have bought a $99 camera as well, not a 40D body.

reg · Jul 13, 2008

No, I just think that if you're a total noob to photography you should really just read before making more lens purchases.

If you have enough disposable income to get a $800 lens without even knowing the basics of photography, then more power to you. I guess I'm just more "old school" in my style of spending.

I mean come on you didn't even know that your mount is called "EF". Now that's just sad.

Dryfly · Jul 13, 2008

I was not afraid to ask. Now I wish I had not.

reg · Jul 13, 2008

Either way, you got your answers.

Dryfly · Jul 13, 2008

Cranky old bugger arnt ya!

Hobbes · Jul 13, 2008

hehe I think he just wanted to help so no need jumping on him like that. I am quite of a noob to photography myself but I am learning and thanks to these guys I have decided to get a eos 40D as my very first DSLR

reg · Jul 13, 2008

Dryfly said:
Cranky old bugger arnt ya!

If only you knew.

:er:

Alex_B · Jul 13, 2008

reg said:
You don't need L glass if you don't know what f/4 means.

I agree and disagree here at the same time.

I know some people who know nothing about the technical terms, or how camera and lens work together. still they take stunning pictures which i would consider art. give some of them better lenses, and their images get better!

Strange world, isn't it

Not everyone has to be an optical engineer to take photographs.

However, you are right, learning about all these things helps to easier achieve the kind of image you want to create. it eliminates some trial and error and also it helps when discussing technique with other photographers and when trying to improve.

By the way, that lens is a very good one, good value for money. however the shortest length at 17mm would not be short enough for me, and the 40 would not be long enough on a 40D. So I would love that lense in combination with your camera, but in addition I would want an ultra wide angle and a longer lens as well.

Alex_B · Jul 13, 2008

reg said:
L originally stood for "aspherical" *well, really, early in the EOS timeline it was AL, then just aspherical, then the aspherical ones became called L. Now it's generally understood to mean "luxury".

I was told it stood for low dispersion .. as in having enough fluorite glass to lo reduce dispersion problems. But I might be mistaken here.

tirediron · Jul 13, 2008

Dryfly said:
Cranky old bugger arnt ya!

reg · Jul 13, 2008

Alex_B said:
I was told it stood for low dispersion .. as in having enough fluorite glass to lo reduce dispersion problems. But I might be mistaken here.

Well I dunno, we might both be. Wikipedia cited the Canon EF Lens Workbook 2nd Ed. for the AL ---> aspherical ---> L naming but when I actually read through it, it says right in there that "The L stands for 'Luxury'". I don't know what year the EF Lens WB 2nd Ed was published, but maybe it really did stand for Luxury all along.

Alex_B · Jul 13, 2008

reg said:
Well I dunno, we might both be. Wikipedia cited the Canon EF Lens Workbook 2nd Ed. for the AL ---> aspherical ---> L naming but when I actually read through it, it says right in there that "The L stands for 'Luxury'". I don't know what year the EF Lens WB 2nd Ed was published, but maybe it really did stand for Luxury all along.

Since luxury means something expensive which you do not really need ... I refuse my L glass to be luxury

Dryfly · Jul 13, 2008

Thanks Alex and to support, this Noob has not learnt a bar of music however plays beautiful classical piano by ear. I have also managed some stunning shots with a p&s and have never known a thing in regards to the technical jargon associated with photography but I am learning now and wanted to take good gear to a course.. Thanks for the info Reg, appreciate it. Thank you all.