Canon t70 - Manual (Page 59)

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[Example S^own: FD 50 mm f/1.4 lens. Maximum ar>d minimum aperturas differ depending pn lens.}
(2) Shutter speed and aperture
MuTibers such as 1 ?
S • ^ S u on the dis*
play panel represent shutter speeds of 1/125
sec or fi250 sec., v^tiile numbers like 1 4.2B.4.
elc. cn ihe Ians opcrlure ring or in the viessimoer
represent apertures, which ore usually called i*
nurrbersor f.'steps.
Each tlrve you rrovc Irom one f.»‘$too to the next
smaller f/stop Uarger number), the arrountof
lignt Is exactly halved. As >cu rrvove irem ere
shutter speed to ihorexth^her speed, exposure
Is sisoholvod
vîcy 1 i*?:a 1 Mi9ft 1«0 ^ IMS
M« Vi ViA \ t** l>S4 1 l<V 1*11
If. fc< example, the comblnatron cf tu and wt 2S
sec. will yield correct exposure, there are certain
other combinations of aperture end shutter
speed which will give you tr>e same amount ot
exposure <EV). (eg f/28and 1/250 sec or
f/5.6 and 1/60 sec)
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