How T O Use The Lmage Defect Cq; Samples - Xerox 3050 Service Manual

How to Use the lmage Defect lmage Quality Definitions
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Samples
Copy quality refers t o the entire copy. The
total copy could have certain defects, such as
damaged media or image quality defects on
the copy.
Always eliminate problems that cause the
damaged media before attempting t o fix
image quality problems. Some damaged
media problems could cause image quality
problems.
The causes for some image quality problems
can be isolated by using the lmage on Drum
(Panic Stop) Procedure (General Procedures in
Section 6).
The imase aualitv defect samples on the
following pages may be used as references t o
identify the defective image quality
characteristics. The majority of the samples
are cropped areas of the defective test
pattern. A reduced area (25 percent of the
original size) gives an idea of how the defect
may appear on the copy while the actual size
sample shows the detail that the defect may
have.
The PROBABLE CAUSE column is most often
arranged in the sequence of the most
probable cause to least probable cause or the
greatest ease to the greatest difficulty of the
check. Opposite each PROBABLE CAUSE is the
CORRECTIVE ACTION for that cause. Read the
entire probable cause list before taking any
corrective action.
Compare the copy defect t o the examples that
are listed on the following pages. After you
have determined the defect sample that best
describes the image defect, perform the
following:
a. Start with the first PROBABLE CAUSE
and continue through the list until you
come to the cause that best applies t o
the copy defect.
b. Perform the CORRECTIVE ACTION.
c. If the defect has been corrected, go t o
the Maintenance Activities in the
Service Call Procedures in Section 1. If
the defect is still present, continue
with the other PROBABLE CAUSES.
The following terms are some of those most
commonly used that describe copy quality
problems.
Background
A degree of darkness or dirtiness that is
overall or localized in the areas of the copy
where no image is present.
Black Copy
A copy that is entirely black except for the
lead edge and trail edge and possibly the
left and right borders.
Blank Copy
A copy entirely without an image.
Cold Flow
A distortion in the selenium alloy coating on
the photoreceptor drum. This defect can
appear anywhere on the copy and will be
perpendicular to the media feed.
(Continued)
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Image Quality Definitions
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