Mirage Auto Lenses User manual

Introduction
   Mirage Automatic Le.nses are available in a r.ange of  rvide-
 angle, tcle.photo and extra-telephoto  sizes.
  They  fit most cameras having a Chinon/praktica type lens
 mount with automatic iris control. Focusing is done at'   full
 aperturc' so that the image in the viewfinJer is clear and br-
 ight. Whcn. making an exposur-e the diaphragm stops Jo*"   to
 thL' prL'-selt.ctt'd aperture and returns to full aperture when the exposure is complet_ed-
Changing the lens
   First remove the lens in the camera. Hold the camera fir_mly in the lef t hand, grasp the lens firmly in  *"  lisht   f,".a
and turn anti-clockwise. Keep turning until the rens is free of
                                                                                tt.,u                                                   Mt."g"Auromatlcl,l:.^"::::.,,b-odv.lens andRemcvetransfertheit rearto thel6nslenscapthatfromhas                                           been                                                               re_
moved. Then insert the Mirage Automatic rens into th"-".-.-ra, by turning clockwise.
 -  This should be done carefully, taking care not to cross thethreads. Screw the le-ns firmiy ho-e" but take care not  toover-tighten, or threads might be .stripped.'

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     Remove the lens cap from the front and your camera is re-
   ady to use. Accessories such as filters and lens hoods,can be
    attached using the front lens thread-

   Holding the camera
     For best results, cup the base of the camera in the palm of
    the left hand and hold lens between thumb and fingers' This
    enables the camera to be held firmly and safely whilst leav-
    ing the right hand free to operate the controls. Holding the
    camera this way also enables the focusing ring and aperture
    ring to be turned easily, with the thumb and fingers of the le-
      ft hand-

  Aperture setting
     Set the required aperture by lining-up the desired f-number
   . against the indicator. Focusing is done at  full aperture and   the lens diaphragm steps down to the pre-selected aperture as
l   exposure is made.
L

Focusing
  Use the focusing ring to obtain correct focus, whilst watc-
hing the image in the viewfinder of the c&mera. After  focus
has been achieved turn the ring each way, slightly, to  ensure
 that the focus is absolutely correct.
Distance Scales
  Focusing can be done quickly, but approximately, using the
distance scale and indicator. Always ensure correct  focus by
obtaining the clearest possible imlge in the viewfinder.
  The distance scale is useful in flash photography, when ca-
mera to subject distance may be required for calculating co-rrect exposure.
Depth of  field
  Depth of  field is the area in front of and behind the subj-
ect that is acceptably sharp. Anything outside these two are-
as will be out of focus, to varying degrees. The depth of  fi-eld is partly a product of the aperture. The smallei the ap-
erture (i. e. the larger the  .f  ' stop number) the greater  will
be the amount in sharp focus behind and in froni of the sub-

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 ject. Moving the camera further away from the subject also
increases the depth of  field-
  The focal length of the lens also affects depth of   field.
The longer the focal length the shallower is the depth of  field
The shorter the focal length, the greater will be the  depth
of  field- So, telephoto lenses have a shallow depth of  field and
wide angle lenses have a much wider depth of  field-
   Selecting the amount of depth of field can add to the cre-
ative quality of the photographs obtained- Subject matter can
be ma,de to stand out by having the background out of focus.
 Similarly, in portraiture, an out of focus background can con-
centrate attention of the subject's face.
Depth of field scale
  The lens has a depth of field scale engraved between the
focusing and aperture rings. This takes the rorm of a  Couble
set of  f stop numbers on either side of the red indicat<,r.
  The nearest and furthest limits & acceptable focus will  be
shown, on the distance scale, against thl appropriate  f stop
numbers. See diagram.

Depth of field visual check      www.butkus.us
    With many modern SLR cameras, the depth of  field can be
   checked visually. When automatic metering is operating, the
    first  part of  the depression of the shutter release button
   usually steps-down the diaphragm so that what is in  focus,
   and what is not, can be seen in the viewfinder.
   Infra- red photography
    When using infra-red film an extra focusing adjustment has
   to be made. After focusing, note the distance figure opposite
   the indicator and then set this figure against the 'R'  indica-
   tor, by rotating the focusing ring clockwise.
  Care of the lens
    Always keep the front lens cap in place when the  camera
   is not being used, to protectect the lens from dust and scra-
   tching.
    Always align lens thread and camera thread carefully, to Ev-
  oid danger of .crossed-thread'.  Similarly, take care *h.r,
  aching accessories to the front of the lens.                  "r,-

t   "rb

Clean your lens only with an air brush, soft camel-hair br-
    ush or lens cleaning cloth. The Dixons blower brush is  ideal
    for removing dust and the Chinon lens cloth is  particularly
    recorrunended for removing grease and marks from the  lens
    surface. Never rub the lens surface with tissue, paper or ot-
    her abrasive materials. These can scratch the lens and cause
I    permanent damage.
     Keep lens free from moisture. Preferably store  it in its case
    with a packet of silica gel.





    Because we continually strive to improve
    our products we may change specifications
    without prior notice.