Originally Posted by Les McLean
I have used cold light heads for about as long as you have. Speaking from the perspective of someone who has dealt with electrical design considerations for well over 35 years, I feel confident that an 8X10 cold cathode lamp requires a heck of a lot more current then any 4X5 or 5X7 lamp. That current inrush consideration is certainly different then lamp brightness fluctuations.
A supplementary relay is a lot less expensive then a new timer. Additionally, for someone on a budget there are light integrators available on the used market today. These are devices that were used to monitor and control time related to light output in plate burners in the graphics industry. The cost of these used devices (many in excellent condition) is a lot less then a RH designs device.