I've got an Ilford 500 head mounted on my Durst L1200. I've heard talk of swapping out the green filter for a yellow one for better contrast control. From Chris Woodhouse of RH Designs: "The yellow/green thing is all about getting the maximum range out of modern papers. The Ilford MG head was designed for MG III paper. Paper has moved on since then and I found that the green filter was not soft enough to get the softest contrasts from Ilford and Agfa paper. I substituted for a standard yellow one from a colour head and extended my grade range. Of course, the downside is that you need to re-calibrate, but we include cal charts for the common papers. Agfa MCP and MCC is now Adox MCC and MCP." Has anyone tried this yet? Can you recommend a source for the yellow dichroic glass?