DSLRs and focal length

[aladyforty]

Im told that a 18-55 lens is actually longer on a DSLR, how does one work out the focal lengths on each lens.

[lemondster]

depends on what camera you are refering to...

being that you are asking about an 18-55 i will assume it is the Canon EF-S lens that comes on the Rebel, Rebel XT and the 20D.

in this case, any lens on those three cameras would have a 1.6 multiplication factor to get the same FOV as the 35mm equiv. this is caused by the CMOS sensor being smaller than a 35mm piece of film.

therefore your 18-55mm lens would appear to be the same as a 28.8mm - 88mm lens.

[aladyforty]

so all lenses are multiplied by 1.6 on a digital rebel 300D?

[lemondster]

aladyforty wrote:

so all lenses are multiplied by 1.6 on a digital rebel 300D?

yup.

so, if you are in to long range photography, you benefit by getting more zoom for the money, but you lose the very wide angle (which is why canon packages an 18-55mm lens on their Digital SLRs and a 28-80/90mm lens on their 35mm SLRs)

[aladyforty]

Thanks:-)