I got my Mark III last Friday. The ISO out of the box had a range of 200-3200. I then thought it was funny that I couldn't get an ISO of 100, but went on to setup the Custom funtions. In C.Fn.1: Exposure #3 is the ISO speed range. I went through the steps and registered the 6400 (H) and 50 (L) settings and applied them, but they still would not go to them when I tried. I registered them several times without any luck and so finally I did the "Clear all custom funtions" thing. I went back and re-set all the custom funtions, including the ISO speed range and this time I could change the speeds through the whole range of L to H.
A little while later I realized that I was back to the 200-3200 range again. I redid the whole thing again and got the L - H back again, but again it didn't last. I then thought that it must have something to do with not being compatable with some other funtion that I was setting, so I did one funtion at a time and went and checked the speeds before I did another one. I changed all custom funtions to what I wanted and I still the ISO range - until I did the final step of choosing the registering and applying custom funtion settings. In this proccess you can register and apply your settings to three differant sets. This is what did it! Once you do this, your ISO extended range is gone! Yes, I had done this on each try of setting up the CF's.
As of now, I have my extended ISO range and all the custom funtions set to what I want, but have not registered or applied them to sets.
Am I the only one to experise this so far or has there been others? If there are others, please let us know here on this forum, because this could be a problem that Chuck/Canon needs to know about. Note: the camera does have firmware 1.1.0 installed.
George,
Even when you have applied the extended iso settings, if you have
CF11-3 Hightlight Tone Priority set to Enable, you will not get the extended settings.
Mike
White Balance so easy, even our 5 year old can do it.- Melissa Strickland
Thank you guys! Somehow when I went through the setting up of Custom Functions I missed that sidebar note on the highlight tone priority. I would think that Canon should have made that a little better known as I'm sure a lot of people will be puzzled at first why they can't go below 200 ISO.
Thank you guys! Somehow when I went through the setting up of Custom Functions I missed that sidebar note on the highlight tone priority. I would think that Canon should have made that a little better known as I'm sure a lot of people will be puzzled at first why they can't go below 200 ISO.
It is a bit puzzling how all the different things interact, and the large impact they have on the buffer size too!
For highlight tone priority though there is a dead giveaway in that the speed is shown as 2oo rather than 200, so once you know this, it's very obvious when you have highlight tone priority on or not.
White Balance so easy, even our 5 year old can do it.- Melissa Strickland
Mark III extended ISO issue 
With Highlight tone priority set, ISO200 is the lowest. I don't know why, doesn't make sense to me.
Linear Mode
