I am a Canon 7D shooter, and would really love to have the feature to "exposure lock" my auto-iso in manual mode with the click of a button. Besides sending in a request for this feature, I thought it would be simple enough for me to code as a Lua script.
The idea is as follows. I put my camera in manual, with spot metering and auto-ISO. I set the shutterspeed and aperture I think is suitable for the scene. I point the camera at my subject, such that my spot metering finds the correct ISO value for my exposure. This is where the script comes in: I then press a dedicated button (ideally the (*) button, but could be the info or set button too) and now the ISO is frozen. Now I can recompose and take my picture. I can than press the dedicated button again to get back in auto-ISO. The process can now be repeated. Maybe it can even be optimized one step further such that the camera is only very briefly in auto-ISO and then almost instantly freezes the ISO value. This way only one press of a button is required. (Basically AE lock hold as found on newer camera's).
So far I have the following script. However I can't seem to manage to get the current value of the ISO as set by the auto-ISO. I already looked at the "copy2m.lua" file as an example, however as a Lua noob, I have a hard time understanding how that script works.
Questions:
1) Is there a simple way to get the ISO value as determined by the auto-ISO
2) I couldn't find the button event for the (*) button in the documentation. Is it possible to use this (*) button for this purpose?
Thank you for your reading!
The idea is as follows. I put my camera in manual, with spot metering and auto-ISO. I set the shutterspeed and aperture I think is suitable for the scene. I point the camera at my subject, such that my spot metering finds the correct ISO value for my exposure. This is where the script comes in: I then press a dedicated button (ideally the (*) button, but could be the info or set button too) and now the ISO is frozen. Now I can recompose and take my picture. I can than press the dedicated button again to get back in auto-ISO. The process can now be repeated. Maybe it can even be optimized one step further such that the camera is only very briefly in auto-ISO and then almost instantly freezes the ISO value. This way only one press of a button is required. (Basically AE lock hold as found on newer camera's).
So far I have the following script. However I can't seem to manage to get the current value of the ISO as set by the auto-ISO. I already looked at the "copy2m.lua" file as an example, however as a Lua noob, I have a hard time understanding how that script works.
Questions:
1) Is there a simple way to get the ISO value as determined by the auto-ISO
2) I couldn't find the button event for the (*) button in the documentation. Is it possible to use this (*) button for this purpose?
Thank you for your reading!
Code Select
isostate = 1
function freezeautoiso(key)
if key == KEY.INFO and camera.mode == MODE.M then
if isostate == 1
isostate = 0
[b]camera.iso.raw = ???[/b]
else
isostate = 1
camera.iso.raw = 0
end
return false
else
return true
end
end
event.keypress = freezeautoiso