We have to check if override cause any change:
1. image processing
2. exif data
3. nothing
AFAIK it common override image processing does work, but exif doesn't reflect changes.
Best to go with big differents in settings, so its easier to spot any changes to image.
Here there is a sample of my results
TV mode, on the left I choosed iso 16, on the right iso 125. Both are from TV mode 10''
http://img695.imageshack.us/i/iso125iso13.jpg/
I tried some more times and it seems that the image quality is better both in raw and in jpg using iso 16 (that I obtained requiring ISO 20).
i find how can get ISO overwrite better working.in platform/generic/shooting.c
i change shooting_set_iso_real.
but this of course does not work with older Kamera.i try to move the function to platform code, but not work
PROPCASE_ISO_MODE
on new camera contain a real iso value.but you can not set any iso value.
values that work is
125
160
200
320
400
640
800
1000
1250
1600
2000
If you choose a value that is not in the table exif and ISO view of Canon firmware round to near value of this.exposure is always correct.
when you have not press the shutter half and not set in iso overwrite any of this values i list, and stay in shooting mode, the preview is green channel only .when you press shutter half, then preview have correct colors and record image look ok.
below ISO 125 is not possible.
when you search for hex values of ISO, for example 800, and look that near hex values of the instruction are too in the table, you can find code in Canon Firmware.
but i do not understand this, it look that it set another control register depend on this values.
I only do in debug view a compare of props, but i do not find a new value that is not in propcase 4.
other ISO values need not set.
void shooting_set_iso_real(short iso, short is_now)
{
long iso2=iso;
if ((mode_get()&MODE_MASK) != MODE_PLAY){
if (iso>0){ _SetPropertyCase(PROPCASE_ISO_MODE, &iso2, sizeof(iso2));
//_SetPropertyCase(PROPCASE_SV_MARKET, &iso2, sizeof(iso2));
}
}
}
because our camera have no KEY_DISPLAY to get alt +/- debug action work(to change prog page easy with that key or compare progs with previous), i hack the code to get usable.
Must be do in core/gui.c
#if !CAM_HAS_ERASE_BUTTON
//Alt mode
- #define SHORTCUT_TOGGLE_RAW KEY_DISPLAY
+ #define SHORTCUT_TOGGLE_RAW KEY_SET
#define SHORTCUT_MF_TOGGLE KEY_UP
but of course for normal use its usable in that way, every set button change raw save on or off.Its only usefull to watch for prop values.
but maybe somebody have a better idea.I use set, because this key is not need important, key right can do same, and i use this to enter in menu.
I see that key left always in chdk do not work to go to previous menu, i find that good too.
EDIT:
to get the ISO value show correct you need also call the function "BL shooting_expo_param_override\n" // + earlier
I add this in Ixus1000 capt_seq.c
"loc_FF883700:\n"
+ "BL shooting_expo_param_override\n" // +
"BL sub_FF883D88\n"
"BL shooting_expo_param_override\n" // +
"BL sub_FF880F24\n"
as far i understand chdk it doesnt matter to call this function twice, because bracketing depend on file numbers.
what i think is not good in chdk, is that bracketing in series mode, do not reset values after some shoots.
for example when i shoot in series mode and press and hold shoot key, the values are always change.i think better is, when can choose that after 1 or 2 or 3 or 4 or 5 or 6 or 7 the values are reset to default.
