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EV bracketing with TV and AV commands[]

Rem written for A710is by Stebu

There are several commands for getting and setting the aperture and the speed. They only work in Manual mode; well you can change the settings in any mode, but they are effective in manual mode, probably also in Av and Tv modes). The commands are

 get_tv target
 set_tv_rel val 
 set_tv val
 get_av target
 set_av_rel val
 set_av val

Target is the name of a variable (a, b, ..z), val is an expression. I used the following script to study the behaviour of these commands. a controls the execution a=0 reads the current settings, =1 sets Tv=b, =2 sets Av=c, =3 sets both and changes the screen display by performing half_click. a=4 runs the bracketing scritp and takes three shots with -2/3, 0 and + 2/3 corrections to the existing manual settings.

On my camera these seem to work.

rem A710is, Stebu, 17.05.2007
rem testing av and tv commands, use Manual mode
@title TV_AV test
@param a get setTv Av set_get brkt
@default a 0
@param b TV
@default b 20
@param c AV
@default c 10
@param d delay (10ms)
@default d 10
 
if a=0 then goto "read"
if a=1 then goto "set_tv"
if a=2 then goto "set_av"
if a=3 then goto "set_get"
goto "bracket"
 
:set_get 
set_av c
set_tv b
print "AV,TV set to",c,b
sleep 1000
click "shoot_half"
sleep 10*d
goto read
 
:read 
get_av n
get_tv m
print "AA,TV got",n,m
end
 
:set_av 
set_av c
print "AV set to",c
end
 
:set_tv 
set_tv b
print "TV set to",b
end
 
:bracket 
rem increase light (1/3+1/3 steps)
set_tv_rel 0-1
set_av_rel 0-1
shoot
sleep 10*d
rem decrease light to original
set_tv_rel 1
set_av_rel 1
shoot
sleep 10*d
rem decrease light
set_tv_rel 1
set_av_rel 1
shoot
sleep 10*d
rem back to original settings?
set_tv_rel 0-1
set_av_rel 0-1
click "shoot_half"
end
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