Pentax K-5 Operating Manual page 127

You can select the number of recorded pixels from _, _, _ and
The more pixels there are, the larger the picture and the bigger the file
size. The file size will also vary according to the [JPEG Quality] setting.
The default setting is _.
Recorded Pixels ' Pixels ' Papersize
16M 4928x3264 14"x17" / A2 paper
10Mi 3936X2624 10"X 12"/A3 paper
6M_ 3072X2048 8"X10" / A4 paper
2M_ 1728x1152 5"x7" / A5 paper
The paper sizes above are references for optimal printing by recorded
pixels. The quality of the captured photo or printed picture depends on the
quality level, exposure control, resolution of the printer and a variety of
other factors.
I
2
3
Select [JPEG Recorded Pixels] in the [1_1 Rec. Mode 1]
menu and press the four-way controller ( • ).
Use the four-way controller (• •)
to select the number of recorded
pixels and press the OK button.
When the number of recorded pixels is
changed, the number of pixels appears at
the top left of the screen and the number
of recordable images for that setting
appears at the top right of the screen.
Press the
MENU
button.
The camera is ready to take a picture.