Problem plates explored

Ok following on from yesterdays weird problem plates outdoors heres some test plates done in the studio.

Firstly the original camera and chems but in the darkroom to get rid of any fogging query. As you can see we still have issues along the plate.
problemplate01

Next change the camera in case of light leaks.
problemplate02

Ok how about chemical fogging. I poured a plate in the darkroom, sensitized and dev’d etc. A clear plate. So no to that.

I then tried a different silver bath (thanks John)
problemplate03

Eureka! A nice clean plate. So maybe the silver bath. I tested the sg of my bath…..sg 1.05 oops should be nearer 1.07. 20g of Silver Nitrate later and we’re back to normal-ish.
problemplate04

A little bit more silver and it should be right. And judging by these plates “Plates of Kirsteen” it looks to be sorted. Mind you these are also with a fresh batch of dev!