Darkroom timer android app

Today I was testing Helios 44-2 lens on my enlarger and it seems to work fine. I still have to carefully inspect the prints, but I’m pretty sure they are much much sharper. One problem is that red filter holder, that i removed red glass from and use it as contrast filters holder, doesn’t fit under the lens anymore. It seems that easy fix is to just slap the contrast filter right on the condenser…