I recently bought a Durst M601 in mint condition. It came with a 150W bulb (+ identical new spare). Any idea if this might have been the original configuration / recommended wattage? The enlarger head gets very ( ! ) hot after a short while and even at f.16 I cant seem to push exposure times to more than max 10-11 sec which give me very little time to work on my print.. I haven't been in a darkroom in 20 yrs so quite rusty : ) Have I missed something or is the bulb wattage way to much? Also appreciate any info on use "modern bulbs" like LED etc. in the M601. Thanks!