Digital SLR Photography - UK (2019-12)

If smallaperturesprovidethemostdepth-of-field,then

surelyshootinglandscapesat yourlens’sminimum

apertureis thebestwaytogeta scenesharpfromfront

toback?It wouldbesomucheasierif thatwasthecase,

butwithsmallaperturescomesa typeofdistortion

calleddiffractionthatactuallysoftensthedetailsin your

image.It’scausedbylightclippingtheedgesofthelens’s

aperturebladesasit passesthroughthelensandcauses

animagetosoftenandimagequalitytodegrade.The

smallertheaperture,themorediffractionnegatively

affectssharpness,butthepointat whichdiffraction

becomesanissuecanbesignificantlydifferentfromlens

tolens– dependingontype,brandandopticalbuild

• butasa generalruleofthumb,avoidstoppingdown
  beyondf/16.A mid-apertureoff/8-f/11ona wide-angle
  lensandAPS-Ccamera,orf/16ona full-frame,is usually
  sufficientforfront-to-backsharpnesswhenusedwith
  hyperfocaldistancingorsimilarfocusingtechniques.

DIFFRACTION

BE A SHARP SHOOTER

Maximise sharpness, image quality

and depth-of-field by mastering

focusing and aperture techniques.

Right: It makes sense to want to use your lens's full range of

apertures but for depth-of-field don't be narrow-minded.

December 2019 Digital SLR Photography 53

IMAGE

S: MARK B

AUER

F/8

F/16

F/11

F/22