Much higher reads quality by megalodon than Guppy

[yanchunzhang]

Hi, I found a very confusing result that when I run megalodon and guppy on the same datasets, the resulting reads quality in the summary file are largely higher in results. I got median reads quality around 10 by Guppy and 20 by megalodon, that's a R9.4.1 run. Do you know why? Is there any mechanism of megalodon to increase the reads quality significantly?

Thanks, Yanchun

[marcus1487]

How are you computing this read quality for the two runs? Megalodon read qualities are derived from the guppy server and thus should match guppy exactly.

[yanchunzhang]

How are you computing this read quality for the two runs? Megalodon read qualities are derived from the guppy server and thus should match guppy exactly.

Thanks for you reply! I computed the read quality for same run. The quality was extracted from the summary files generated by guppy or megalodon, is there might be a problem for megalodon to derive correct read quality from guppy server? I can upload the summary file if you need.

Yanchun