For printing very large photos, capture the images in RAW format and make any processing corrections in post before saving as a TIF file for printing. JPG compressed files work fine for many uses but when trying to print the largest image size possible, you don't want any information discarded prior to printing and TIF files are the best in this respect.
And depending upon what you are trying to capture, it may be possible and advisable to capture it as a matrix of images which are stitched together in post before sending to print. This is a great approach to printing very large, very high resolution landscape images because instead of one 30 MB set of image data, you have a matrix composed of multiples of this 30 MB sensor data allowing you to print very large images with excellent detail.
Rodger
EOS 1DX M3, 1DX M2, 1DX, 5DS R, M6 Mark II, 1D M2, EOS 650 (film), many lenses, XF400 video
