What is the relevance of the Peptides per fraction chart
On the Import Fractions screen, a graph in the bottom left corner of the window shows how many peptides were identified in each fraction. Ideally, the peptides would be evenly distributed across the fractions.
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If the majority of peptides have been identified in a small number of fractions, Progenesis LC‑MS will alert you to this.
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In such situations, the same quality of results could probably be achieved while creating fewer fractions.