Data from ABI 3100, Phred quality values

[Edith Schlagenhauf]

Hi all,

I have PHRED processed for the first time a batch of traces coming
from an ABI 3100. I was surprised to see that the average
quality for good quality traces is in the range of 60-70.
For traces from an ABI377 these values are usually around 40-50.
Is this real or some sort of artefact?

Any comments on that?

Edith Schlagenhauf
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