ISO 100 and ISO 25600 cannot be set (EOS REBEL T4i/EOS 650D)
15-Jun-2012
8201522300
Solution
If you set [C.Fn II -3: Highlight tone priority] to [1: Enable] on your camera, the settable ISO range will be limited to ISO 200-12800 (up to ISO 6400 for movies), so "ISO 100" or "H"(Still photo: equivalent to ISO 25600, Movie: equivalent to ISO 12800) cannot be selected.
The [D+] icon will be displayed on the LCD panel and in the viewfinder when highlight tone priority is enabled.
If you wish to make the "ISO 100" or "H"(Still: equivalent to ISO 25600, Movie: equivalent to ISO 12800) setting (ISO expansion), change the setting as follows.
1. Set the power switch to <ON>.
2. Press the <MENU> button to display the menu.
3. Press the <Cross Keys> to select [Custom Functions(C.Fn)] under the [ 
] tab, then press the <SET> button.
] tab, then press the <SET> button.
4. Press the <Cross Keys> to select Custom Function No.3 [Highlight tone priority], then press the <SET> button.
5. Select [0: Disable], and then press the <SET> button.
6. Press the shutter button halfway, and the camera will be ready for shooting.
Confirm that [D+], which indicates Highlight tone priority, is not displayed on the LCD monitor and in the viewfinder.
NOTE
About Highlight tone priority
- Improves the highlight detail. The dynamic range is expanded from the standard 18% gray to bright highlights. The gradation between the grays and highlights becomes smoother.
- With setting [1: Enable], noise (grainy image, banding, etc.) may become slightly more pronounced than with setting [0: Disable].
1. Press the <MENU> button to display the menu.
2. Press the <Cross Keys> to select [Custom Functions(C.Fn)] under the [ ] tab, then press the <SET> button.
] tab, then press the <SET> button.3. Press the <Cross Keys> to select Custom Function No.2 [ISO expansion], then press the <SET> button.
4. Select [1: On], and then press the <SET> button.
5. Press the shutter button halfway, and the camera will be ready for shooting.
When you set the ISO speed, you will be able to set "H" (equivalent to ISO 25600) for still photos and "H" (equivalent to ISO 12800) for movies.
NOTE
Note that if [C.Fn-3: Highlight tone priority] is set to [1: Enable], "H" cannot be set.