[dcsoul]

嚗光補償是什樣幫助日間和夜間嚗光 & 影相 ^....^靚靚........
和快門&閃光燈什樣一起運作啊
幫幫手啊Thank ......you^....^

[hytong]

All in-camera meter (except F5 which has a color metering) assumes objects being measured have 18% reflectance. (Your camera instruction booklet should have mentioned that). Which means no matter what color is your object the camera thinks it is medium grey. (or zone system V)

White/bright objects reflect more light than medium grey and black/dark objects reflect less light than medium grey. This fools the camera internal meter and white objects are rendered grey, black objects also rendered as grey.
To combt this situation, you can typically add a stop or 2 for metered white objects and subtract a stop or 2 for metered dark objects.
Other than that you can use a grey card for reflective reading or an incident meter for direct reading.

In B/W photography, you pick an object as medium grey and meter on it.

Realize that every color has a 13% reflectance hue. And not all grey colored object reflect exactly 13%. Examples of medium grey are green grass and (i heard southern?) blue sky.


There is a certain range of contrast that can be recorded on film or CCD. Typically 5 stops for slides/CCD/CMOS and 7 stops for negatives.
Beyond that all dark areas are rendered as black and all bright area are snow white. Which means no detail can be seen.

In order to narrow this range of contrast, fill-flash is used for a back-lit foreground object to bring it closer to the background. e.g. sun behind a person, outdoor situation.

www.photo.net