Canon EFS?? Does Crop Exist???

[Stevedevil]

Hi all, been reading loads after last few days, and have read about the Canon EFS range verses the EF range, and have to ask 1 thing, if the EFS range does not include the crop factor, then my 18 - 55 will be as good as a 10 - 20mm EF ( 16 - 32mm with crop factor ) or am I missing something??? I know that the 10mm lense is f1.4 so that could mean the price tag but hey, we can move ISO to counter act the f stops cant we??

HELP???

 

[Innocence]

mm, not sure what you mean, but your 18-55's field of view is cropped by 1.6x

which means your lens will be 18*1.6 - 55*1.6

The speed has nothing to do with it =)

Hope it helps.

Btw, you don't get extra "reach". So it's "lose lose". =P

 

[Big Mike]

Firstly, are you used to using a 35mm SLR camera? If not...then forget anything you have ever read about crop factor...it's just something to compare 35mm film cameras to digital.

Focal length is always an absolute. 17mm on an EF lens is the same as 17mm on an EF-S lens.

Crop factor refers to the camera...not the lens. EF-S lenses are made for cameras with a crop factor.

You seem to quite confused...and it's confusing me too :scratch: 18-55 is always 18-55. If you have that focal length on a crop factor camera (Canon digital Rebels etc)...then it's a regular FOV (field of view)...but that same focal length on a film camera or full frame digital (Canon 5D, 1Ds Mk II)...then it's a really wide FOV.

So the only time you have to think about crop factor...is when you are switching between different cameras (from film to digital Rebel, for example)...otherwise....crop factor really means nothing.

 

[Alex_B]

the focal length given on the lens is the real focal length for both EF and EF-s

so in both cases the 1.6 crop applies.

hence
18 and 10 are not the same on the 2 lenses ...

 

[Innocence]

haha how funny!

well, to answer your question, if you're using your EFS 18-55 (lens kit?) then yes, the crop factor does exist for you.

and the f/stop (speed) has nothing to do with the crop.

 

[Stevedevil]

The EFS range so I understand takes away the CROP, as EF maintains the FULL FRAME on 35mm, EFS should do the same, but the EFS will not fit any other EF camera, as focal length is adjusted to give 35mm on digital???

Im even more confused now lol ???

 

[Stevedevil]

Thanks for so many replies, if the crop still exists why make a lense that will not fit all cameras, this forum states that the EFS lense gives full frame ( NON CROPPED ) ????

More Confused lol

 

[markc]

The only real difference between EF and EFS is that the EFS lens extends further into the camera. The mirror on larger frame cameras will bump into it, so it will only fit on smaller sensor cameras.

 

[Alex_B]

The EFS range so I understand takes away the CROP, as EF maintains the FULL FRAME on 35mm, EFS should do the same, but the EFS will not fit any other EF camera, as focal length is adjusted to give 35mm on digital???

Im even more confused now lol ???

i think you are ...

18mm EF-s are the same focal length as 18mm EF ... just with EFs the image circle of the lens is smaller ... too small to fill a full frame sensor or 35 mm film.

 

[Stevedevil]

Thanks Markc, but the lense extending into the camera is to take away the 1.6 crop value isnt it??

 

[shingfan]

Thanks for so many replies, if the crop still exists why make a lense that will not fit all cameras, this forum states that the EFS lense gives full frame ( NON CROPPED ) ????

More Confused lol

crop factor is from the camera...not the lense......try to separate the lense from the camera.....things might be a bit more clear that way

 

[Alex_B]

Thanks for so many replies, if the crop still exists why make a lense that will not fit all cameras, this forum states that the EFS lense gives full frame ( NON CROPPED ) ????

no,it does not fill the full frame!

EF-S needs less glass that is why it is cheaper and smaller and lighter

 

[Stevedevil]

I understand the F stops will suffer for this lense, but Im interested in Field of view, as 10-20mm lenses are £400-00 ( $700-00 ) and to gain 2mm at 3 f stops, where a tripod and adjustments on ISO and shutter speed can give same result, I think im missing something??

 

[Alex_B]

Thanks Markc, but the lense extending into the camera is to take away the 1.6 crop value isnt it??

no .. always add 1.6 ... no matter if EF or EF-s

1.6 is the crop of your sensor!

 

[Stevedevil]

The crop factor is the positioning of the sensor in relation to the focal length of the lense isnt it??