Rokinon 85mm f/1.4 with chip issues with flash...
Im new to this forum but not new to photography. I recently purchased a Rokinon 85mm f/1.4 with the chip in it.
I absolutely love it for portraits but when I went to use it in studio with a monolight strobe I noticed that all the pictures that were shot faster than 1/160 had a big black area in the photo. Almost like there is no flash in that area but im positive there is.
Any ideas on how to fix this? Maybe the lens is faulty or I should use an ND filter to keep the numbers in the right range?
here is an example photo
#1. "RE: Rokinon 85mm f/1.4 with chip issues with flash..." | In response to Reply # 0briantilley Nikonian since 26th Jan 2003Wed 27-Nov-13 06:13 PM
The EXIF data in the image says it was taken at a shutter speed of 1/250th sec - which explains the outcome.
The D90's maximum flash sync speed is 1/200th. At speeds faster than that, the shutter curtain is not completely open for the full duration of the exposure - thus leaving an area at one edge underexposed like you see here.
Either way, this isn't a lens problem
#3. "RE: Rokinon 85mm f/1.4 with chip issues with flash..." | In response to Reply # 2briantilley Nikonian since 26th Jan 2003Wed 27-Nov-13 08:21 PM
I don't know that a ND filter is necessary - it's difficult to be sure without knowing the subject, ambient lighting conditions, or the effect you are aiming for, but simply selecting a shutter speed slower than 1/200th should fix the problem