EF-S & EF Lenses
 

Hi all,

I have a crop sensor dslr, a canon.

If i was to buy an EF-S lens, say a 20mm, would it be just that, 20mm?
If I was to buy an EF lens at 20mm would it fit on a crop sensor camera and would it still be 20mm or would it be effectively 32mm because of the 1.6 crop factor?

Are EF-S lenses designed for crop sensor camera's and EF lenses for full frame cameras?

If so, are the two interchangeable with crop sensor's and full frame dslr's?



Thanks
Gratris

[QUOTE=Gratris;87613]Hi all,

I have a crop sensor dslr, a canon.

If i was to buy an EF-S lens, say a 20mm, would it be just that, 20mm?
If I was to buy an EF lens at 20mm would it fit on a crop sensor camera and would it still be 20mm or would it be effectively 32mm because of the 1.6 crop factor?

Are EF-S lenses designed for crop sensor camera's and EF lenses for full frame cameras?

If so, are the two interchangeable with crop sensor's and full frame dslr's?



Thanks
Gratris[/QUOTE]I will se quick :)
Yes, sort of
Yes, and that is the "sort of" from above
Yes
EF and EF-S will fit on crops, but only EF on full frame.

So for the first one, EF-S lenses, even though they are designed for crop sensors are still labeled as if they were for full frame. So 20mm is 20mm.

Someone may come in and give all sorts of angle of view stuff and get very detailed, but we are keeping it simple.

Thanks donoreo, I appreciate the reply.

So I should plan to buy [B]EF[/B] lenses, not [B]EF-S[/B] as these will fit my crop sensor camera and also be of use if I upgrade to a full frame?


Thanks
Gratris

a efs lens will give you the range that the numbers outline.

example the 18-55 efs kit lens on a crop body has the same field of view as an 18-55 on a full frame.

efs will only fit on crop sensor bodies XXXD series, XXXD, XXD and the 7D.

These cameras will also take lenses designed for full frame ( EF) this is the mount that 3rd party manufacture lenses for.

EF lenses will be effected by the 1.6 crop factor so a ef 50mm will be similar to 80mm on a full frame.

In regards to buying new glass, i would recomend going down the ef route. Mainly that they can be used on full frame if you upgrade, and an ef tele has more reach on a crop. Secondly most of the EFS lenses are of beginner origins, except for the 10-22 and the 17-55 2.8 are high performers and the 15-85 and the 60mm macro are more middle ground. ef lenses tend to be higher quality glass and build quality... except for the 75-300.

Thanks Jamie.b,

I appreciate the reply, it now makes a bit more sense.


Thank you.


Regards
Gratris

[QUOTE=Jamie.b;87768]a efs lens will give you the range that the numbers outline.
[/QUOTE]

Yes.

[QUOTE=Jamie.b;87768]example the 18-55 efs kit lens on a crop body has the same field of view as an 18-55 on a full frame.
[/QUOTE]

NO. Absolutely not. 18-55 efs will give the same field of view as 18-55 ef (if there is such a thing) on the same body. It's the body that does the cropping (and therefore gives the 'crop factor'), not the lens.

[QUOTE=Jamie.b;87768]EF lenses will be effected by the 1.6 crop factor so a ef 50mm will be similar to 80mm on a full frame.
[/QUOTE]

ALL lenses will be affected by the crop factor, since that's a property of the body, not the lens. An ef-s 50mm (if there is such a thing) on a crop body would also be similar to 80mm on full-frame.

[QUOTE=Jamie.b;87768]...an ef tele has more reach on a crop.[/QUOTE]

All teles have more reach on crop bodies because the body gives more reach, but I imagine that there are few ef-s telephoto lenses.

Chris

I'm getting confused again.....lol


So the field of view is the same? What would the image look like once the photo has been taken, would it appear different if taken from the exact same place with a crop sensor body and then with a full frame body both using the same size lens? If so, is that because the body crops the image? Basically, you don't get the full image you see through the viewfinder on a crop sensor body?

You would not see or get the same image from the same lens taken on a full frame camera and a crop sensor camera , if you take a printed photo taken on a full frame camera and then cut a strip off the top , bottom and both sides and then enlarge that middle section back to the original size that is the same as the difference you would get between the two different body's . Think of it in the same way as a digital zoom , it looks like you are getting a longer reach but your not it's just a digital enlargement .

If you put in a Google image search for full frame sensors you will get loads of very good visual explanations of how the full and crop sensors work .

Mark

Thanks Mark.

That makes sense to me now.

So for landscape photography on a crop sensor I would need a a shorter lens than on a full frame. Or have I completely missed the point?......lol


Regards
Gratris

That's right , the crop sensor crops the outer edges off the shot compared to a full frame camera so yes to get the same view you would need a wider lens on a crop sensor .

Mark