Auto ISO fix for photographers

Issue #151 on hold
Former user created an issue

Canon messed up when introducing auto-ISO. When shooting in A mode, Auto-ISO will set the shutter speed to one stop slower than the focal length of your lens, with no way of setting minimum or maximum shutter speeds. This ommision completely kills the Auto-ISO feature for action still photographers. If you could hack the firmware in order to manually set a minimum shutter speed when using auto-ISO, this would make Auto-ISO usable again.

Comments (21)

  1. Former user Account Deleted

    I would absolutely love this too. At minimum, it would be fine, for me at least, to change the algorithm to select 1 stop faster than the focal length. It would be so much more useful.

    Of course, the dream would be what the 7D and Nikon have, manual mode with auto-iso with user specified upper limit or range.

  2. Former user Account Deleted

    This would be one of my only uses (along with the auto iso in manual mode) for magic latern. I am a developer and will look into helping out, but I imagine this change should be relatively simple compared to a lot of your other work. Cheers

  3. Former user Account Deleted

    I do wholeheartedly agree, this really is an anoying issue because with the 18MP Canon sensor, shots only a litte faster than 1/focal length are blurred at the pixel level so no 100% crops are possible.

    My suggestion would be to be able to simply set the EV value that is added to the focus lenght (as written above: the default: is 1).

  4. scrax

    On 600D there is already that option (min ISO) but the AUTO iso in 400plus has more options than the one we have on 600D by canon so it would be a good new feat.

  5. Former user Account Deleted

    Hallo. Just found this after getting annoyed that this is a regular feature for Nikon users but not Canon. I looked at the 400plus link that a1ex gave, and the algorithms they describe are exactly what I'm looking for - the ability to specify minimum/maximum Tv speeds and ISO when using Av mode. I am totally new to this custom firmware scene, and Magic Lantern for that matter - what is the procedure for changing the status of this from on hold to something more positive? Does donating help with respect to this?

    Alternatively, I am also very keen to learn more about understanding and building camera custom firmwares. Can anyone offer pointers on what to learn to get started? I am a fairly decent software programmer, but never done anything on embedded systems before.

  6. higgs

    400plus works well, but it lacks an option for ISO with Flash. Basically if you use a flash you don't want to bump up your ISO to maximum. In 400D I have to set ISO manually and re-enable Auto-ISO via 400plus menu after that. If it's not hard it would help to have a limit for max ISO with Flash or simply a fixed ISO.

    Another point to keep in mind is that 5D Mark II auto-iso tracks the focal length and it just doesn't use this information correctly for most users. The ideal solution would be not 400plus one, but a new one with the following options:

    1) a correction for min shutter speed based on current flocal length in a form of number of stops. Most users would be happy with just one stop faster than the default, while with an IS lens, one may prefer 2 stops slower.

    2) absolute minimum for the shutter speed for action in non Tv-modes or min aperture in Tv-mode.

    Hope to see this option implemented soon.

  7. Former user Account Deleted

    Bump. Is anyone still thinking about this? It would truly be a great feature for a great camera.

  8. Antonio Rodrigues

    Another BUMP! this could be a great feature, a AUTOISO just like the 400plus and CHDK. My T2i/550D tends always to put a faster aperture incrising the ISO to the max allowed...

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