Chapter 5 Preparation — Mounting and adjusting the lens

2 Set the screen.

1)Shoot a white sheet of paper with no unevenness of color for the whole screen.

2)Set the lens aperture to manual, and adjust it so that the zebra pattern covers the whole viewfinder screen. ffMake sure that the lens aperture control is between F4 to F11.

ffAdjust the position of the lighting because the zebra pattern will not cover the whole screen if there is any unevenness in the lighting.

ffMake adjustments to avoid several light sources of different color temperature (e.g. fluorescent lights and halogen lamp) from illuminating on the white paper.

3Adjust the white balance/black balance.

1)Set the <WHITE BAL> switch to <A> or <B>, and use the <AUTO W/B BAL> switch to adjust white balance automatically (AWB).

2)Use the <AUTO W/B BAL> switch to adjust black balance automatically (ABB).

3)Use the <AUTO W/B BAL> switch to adjust white balance automatically (AWB) again.

4Perform step 2-2) again.

5Adjust white shading.

1)Adjust from [R H SAW] to [B V PARA] in the main menu → [MAINTENANCE] → [WHITE SHADING] to make a flatter waveform.

6 If the lens is equipped with an extender function, turn on the extender function and repeat steps 2 to 5.

Compensation values are stored on the camera as a single lens file data using two patterns for when the lens is equipped and not equipped with an extender pattern.

Adjustment values are saved in memory, so there is no need to re-adjust white shading even after turning the camera off.

@@NOTE

tt Coloring may occur in the vertical direction near where the lens aperture is open (OPEN) even when the white shading has been adjusted, but this is something that is inherent to optical systems and is therefore not indicative of a malfunction.

tt Since fluorescent lights, mercury lamps, and other such kinds of lighting tend to flicker, use a light source which is less subject to flickering such as sunlight or a halogen lamp.

tt Make adjustments to the position of the lighting, etc. also when the lens aperture is not between F4 and F11. tt Make sure to leave the <SHUTTER> switch at <OFF>.

Chromatic aberration compensation function (CAC)

The chromatic aberration compensation function minimizes color smearing in peripheral images. This function automatically compensates for registration error that is caused mainly due to slight chromatic aberration, which is hard to completely compensate with the lens itself, using the camera recorder unit.

When the lens compatible with the chromatic aberration compensation function is mounted, if the camera has the chromatic aberration compensation data of the lens, then the chromatic aberration compensation function is activated automatically.

What is lens chromatic aberration?

B

G

R

“Chromatic aberration” here refers to zoom factor chromatic aberration. Zoom factor chromatic aberration occurs since the diffraction ratio of a lens differs according to red (R)/green (G)/blue (B). Chromatic aberration on the lens itself is compensated for, but still remains in the periphery, in particular. Also, this chromatic aberration occurs on zoom lens due to a complex relationship between zoom ratio, aperture and focal distance. In image terms, this is registration error.

Chromatic aberration compensation function

To compensate chromatic aberration, store the chromatic aberration characteristics of the lens regarding zoom ratio, aperture and focal distance to the camera recorder beforehand. Connect a lens that matches those chromatic aberration characteristics, and perform compensation matched to the zoom ratio, aperture and focal distance of that lens.

The following four types of chromatic aberration compensation function data for lenses are stored to memory before the camera is shipped.

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