Are you using any filters with the MG paper? What size prints? You could also stop down more. I used to use the same light with 120 and 4x5 but with graded paper and don't recall exposures being that short. When I switched to multigrade paper years ago I bought the Aristo 4500 VCL and also never have such short exposures. Double check your lens to be sure it stops down. I can't help with the glass carrier since I don't have one.