This week, when diving mostly with people more experienced than myself, I noticed something about my buoyancy compared to theirs. I'm wondering how to fix it.
Before setting off, we all selected what seemed an appropriate amount of weights. Everyone (possibly after a small change) was able to achieve eye-level buoyancy at the surface after breathing out, so I think we all had about the right amount of weight.
When we'd reach our diving depth, and had put the right amount of air into our BCDs, we all seemed to be floating about level.
Around then, and later when swimming along at that depth, I noticed that the more experienced divers were pretty much staying exactly at that depth, not really varying at all. However, I found myself rising anything up to 2m higher as I breathed in slowly, and falling to up to 1.5m below them as I breathed out. My average buoyancy was the same as theirs, but it varied a lot more with my breath than for them.
What do I need to do / change to have my buoyancy change less at constant depth as I breathe in and out?