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Experimental metering for "ISO Override" for A450

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Experimental metering for "ISO Override" for A450
« on: 13 / April / 2008, 03:59:09 »
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Here is my second script for ALLBest Build

This Script ONLY Support A450 and Possible Some DIGIC III PowerShot

This Script used DIGIC III PropertyCase.
If someone want to Implement this script to DIGIC II Powershot.
You can try Change the "set_prop 262 t" To "set_tv" or change the correct propertycase number refer to the Digic II.

Version History
v0.1 ---- inital build (possible final?)


Usage:

1. Go to "Main Menu" -> "Extra photo operations menu" set your needed Override ISO value and Value Factor
2. Use this script to take a shoot
3. That's All :D

Remarks : Make sure your ISO value is workable with your Powershot otherwise you will have the wrong exposure.
Code: [Select]
rem A450 Sv Mode
rem By MP9SIT at 20080413
@title Sv Mode

press "shoot_half"
sleep 1000
get_av96 h
get_bv96 i
get_sv96 s
release "shoot_half"
t=i-h+s
if t<-576 then
t=-576
set_led 8 1
endif
press "shoot_half"
sleep 1500
set_prop 262 t
press "shoot_full"
release "shoot_full"
set_led 8 0
release "shoot_half"
end

Re: Experimental metering for "ISO Override" for A450
« Reply #1 on: 13 / April / 2008, 04:06:24 »
Sample Here

_Auto -> Metering Fully controlled by the camera (Surely wrong after override? :lol)
_Script -> Metering with script

Re: Experimental metering for "ISO Override" for A450
« Reply #2 on: 13 / April / 2008, 07:21:55 »
Deleted
« Last Edit: 22 / April / 2008, 17:36:39 by Barney Fife »
[acseven/admin commented out: please refrain from more direct offensive language to any user. FW complaints to me] I felt it imperative to withdraw my TOTAL participation. Nobody has my permission, nor the right, to reinstate MY posts. Make-do with my quoted text in others' replies only. Bye

Re: Experimental metering for "ISO Override" for A450
« Reply #3 on: 14 / April / 2008, 15:32:43 »
Interesting script... let's test it...

Canon A570IS on AUTO,
1. Auto High ISO, shot taken at ISO 800
2. Auto High ISO, script shot at ISO 800 - barely a difference
3. Auto ISO, shot taken at ISO 200
4. Auto ISO, script shot at ISO 200, longer exposure, looks nice and sharp.

The pictures have the original EXIF. It is a better way to get what you see in terms of metering, but the exposure time will kill you. Don't expect this to work in hand free or moving objects scenes. I go manual usually, so I won't really use this script, great job anyway!  8)

Tested when using the flash, it increases the exposure time from 1/60 to 0.6 and lowers the flash output. Nice color range, might change my mind about it...
« Last Edit: 14 / April / 2008, 15:39:47 by mrproper »


Re: Experimental metering for "ISO Override" for A450
« Reply #4 on: 14 / April / 2008, 21:10:53 »
Interesting script... let's test it...

Canon A570IS on AUTO,
1. Auto High ISO, shot taken at ISO 800
2. Auto High ISO, script shot at ISO 800 - barely a difference
3. Auto ISO, shot taken at ISO 200
4. Auto ISO, script shot at ISO 200, longer exposure, looks nice and sharp.

The pictures have the original EXIF. It is a better way to get what you see in terms of metering, but the exposure time will kill you. Don't expect this to work in hand free or moving objects scenes. I go manual usually, so I won't really use this script, great job anyway!  8)

Tested when using the flash, it increases the exposure time from 1/60 to 0.6 and lowers the flash output. Nice color range, might change my mind about it...

It work with Flash? In fact i haven't handle the things about Flash :D
And the Tv mode script should be more useful when you want to use extreme fast/slow shutter  :P

Re: Experimental metering for "ISO Override" for A450
« Reply #5 on: 15 / April / 2008, 09:40:23 »
Here is my second script for ALLBest Build

This Script ONLY Support A450 and Possible Some DIGIC III PowerShot

This Script used DIGIC III PropertyCase.
If someone want to Implement this script to DIGIC II Powershot.
You can try Change the

Quote
get_prop 107 e
set_prop 262 t

To the correct propertycase number refer to the Digic II.

Version History
v0.1 ---- inital build
v0.2 ---- Added +/-2EV Support (Base On original Canon's Setup)

Usage:

1. Go to "Main Menu" -> "Extra photo operations menu" set your needed Override ISO value and Value Factor
2. Use this script to take a shoot
3. That's All :D

Remarks : Make sure your ISO value is workable with your Powershot otherwise you will have the wrong exposure.

Code: [Select]
rem A450 Sv Mode
rem By MP9SIT at 20080415
@title Sv Mode

press "shoot_half"
sleep 1500
get_av96 h
get_bv96 i
get_sv96 s

get_prop 107 e
if e>65000 then
e=65536-e
endif

t=i-h+s-e
if t<-576 then
t=-576
set_led 8 1
endif


set_prop 262 t
press "shoot_full"
release "shoot_full"
set_led 8 0
release "shoot_half"
end


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  • Nikon D40x & A460
Re: Experimental metering for "ISO Override" for A450
« Reply #6 on: 27 / May / 2008, 03:59:40 »
With ISO override (Extra Photo operations) I was able to get the 'commercial' ISO 1000, with a real ISO I think around 5-600. Lowest ISO that made a difference was (real) 40. An interesting side-effect was that the commercial ISO was written to EXIF.
I think these are the usable ranges for A450/A460, though the picture at '1000' ISO is not much of use in the dark.

Re: Experimental metering for "ISO Override" for A450
« Reply #7 on: 17 / June / 2008, 11:35:34 »
With ISO override (Extra Photo operations) I was able to get the 'commercial' ISO 1000, with a real ISO I think around 5-600. Lowest ISO that made a difference was (real) 40. An interesting side-effect was that the commercial ISO was written to EXIF.
I think these are the usable ranges for A450/A460, though the picture at '1000' ISO is not much of use in the dark.

I made some test in A450 before. If i haven't get any wrong the max it can be go to 'commercial' ISO 1250 = Real ISO 800 :D


 

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