Auto ISO issue

[jimmy156]

Hi all,

Noticed something a bit strange today when taking a few shots in London. Normally i shoot in either apeture or shutter priority, and set the ISO to whatever i feel it needs to be. Today i thought i would shoot in Manual to give me control over both apeture and shutter speed, and let the camera sort out what ISO was needed, so i set the ISO to Auto. The issue is that when set to Auto, it would not move off ISO400. This is only the case in Manual mode, with Auto ISO working as i would expect in both Av and Tv modes.

Any idea's?

Cheers, James

[paul911]

Yup ISO 400 is correct if you set it to auto in manual. Your shooting in manual so the camera assumes your going to select the ISO too. Auto ISO does work in Tv and Av, and does a great job too.

[jimmy156]

Fair enough, i had thought it must be something like that! Thanks for clearing that up

[Killwilly]

Thanks Paul. I also assumed that the camera would choose the ISO when set to auto, even in manual. Thinking about it,"manual" gives the photographer the opportunity to make all of the choices.

[andy-xr]

Be thankful in a way, the little D40 I have automatically rams itself up to 1600 given the opportunity

[jimmy156]

andy-xr said:

Be thankful in a way, the little D40 I have auomatically rams itself up to 1600 given the opportunity

sounds like a right pain.

Interestingly, talking to my colleague today, he reckons Auto ISO does work in manual on his 7d...

[dogbucket]

I dont know what camera you have but I seem to remember the lowest my 40D would go in auto ISO was 400 and work up from there.

7D and 5Dmk2 will auto select down to 100, and in a fairly intelligent manner it seems.

[jimmy156]

dogbucket said:

I dont know what camera you have but I seem to remember the lowest my 40D would go in auto ISO was 400 and work up from there.

7D and 5Dmk2 will auto select down to 100, and in a fairly intelligent manner it seems.

Ah okay, i have a 50d so i can probably assume its the same, and the conditions didnt warrent an ISO over 400. Will test this tonight, thanks!