MACS2 extsize parameter problem

Question

[xd_d]

Hi all,

I have a question about the parameters of MACS2?

What does the parameter --extsize with my reads/tags

input reads as treatment.

name /start/end chr1 1 100 +

when i set --extsize 50 then my new read is chr 1 51 ?

I ask because when I call peak on multiple chr1 1 100 +,chr1 1 100 +,chr1 1 100 +

then i get with --exitsize 50 => peak_1 chr1 1 51

But why not peak_1 chr 1 150 ?

please help : )