Does anyone know how to adjust a raymarine c or e series to read 250feet on side and 500 on the other. I used to be able to do this on my old furuno, But i have since upgraded. I love doing this at night but i just cant seem to figure it out. If i did not explain what i want correctly i can link a picture, but im not in to linking from other site's.

Thanks in advance all

-Deane