Playing with the AA4 dimmables

I recently got 12 atlas Atlantic 4 fittings from a school that was still running these with all the tubes you see here until 3 weeks ago. Here they are connected to my furse unit and doing some dimming tests on it out of all 12 fittings 24 lamps 3 were until when they were still in situ in the school these turned out to be bad / contaminated / failed lamps only the fittings and control gear are mint despite 51 years of use.