I recently returned from a photo trip to Lone Pine California. I found that my e xposures on Fujichrome RVP (Velvia) were on the dark side. I shot 4x5 sheets, lo aded myself, at ISO 50. I found that all the exposures made during full "sun up" conditions were spot on exposure wise, but that the shots taken under low light conditions were almost all too dark. I used exposure compensation for a number of "sun up" shots to acount for the po lerizing filter I was useing, and found that my compensation was very accurate. On the low light shots (almost all taken after the sun had gone down) I compensa ted for Reciprocity falure useing the corrections given in Steve Simmons' "USEIN G THE VIEW CAMERA". I shot some images at exposures of 58 seconds or more, but s till found them darker than I wanted them. Has anyone experienced this problem. I would change the ISO, but for the fact that "sun up" exposures were dead on. D o I need to change the ISO only for the low light shots? Is this a regular "thin g" with RVP? Are Simmons Reciprocity corrections accurate for RVP? Please Advise .

Thanks, Bill