Pentax AF 330 Operation Manual - Page 16

When

Using

the

"A"

(AUTO)

Lens

Aperture

Programmed

TTL

Auto

Flash

is

possible

with

the

AF330FTZ

when

the

Programmed

AE

or

Shutter

-

Priority

AE

mode

is

set

on

a

camera.

The

flash

sync

speed

and

aperture

value

automatically

vary

depending

on

the

subject

brightness

as

with

the

camera's

built-in

flash,

making

it

suitable

for

daylight

sync

flash.

When

Setting

the

Lens

to

a

Manual

f/stop

When

the

Aperture

-Priority

AE

or

Metered

Manual

mode

is

set

on

the

camera,

TTL

Auto

Flash

is

possible

with

the

desired

aperture

selected

to

control

the

depth

-of

-field.

In

Metered

Manual

exposure,

slow

-speed

-sync

flash

is

possible.

14

Calculating

the

Flash

Effective

Range

When

setting

the

lens

to

a

manual

f/stop,

calculate

the

guide

number

at

FULL

output

strength

with

the

use

of

flash's

zooming

position

and

film

speed.

Divide

the

resulting

guide

number

by

the

aperture

in

use.

Thus,

the

maximum

distance

is

obtained.

The

minimum

distance

is

obtained

in

dividing

this

max.

distance

by

approx.

10.

Example:

With

IS0100

film

and

a

50mm

lens

at

f/4

1)

For

the

zoom

position

=

50mm,

and

film

speed

at

IS0100,

the

guide

number

is

28.

2)

The

aperture

is

f/4,

28

(guide

number)/4

(aperture)

=

7m

(max.

distance)

3)

7m

(max.

distance)/10=0.7m

(min.

distance)

Thus,

flash

effective

range

is

approx.

0.7-7m.

Pentax AF 330 Operation Manual - Page 16

distance/10=0.7m - af330ftz ttl

Page 16 highlights