ffmpeg commands - image sequence to mp4

Listing some of the ffmpeg commands used in my previous post - 

ffmpeg -r 30 -start_number 1326 -f image2 -i "OpenSpace_%06d.png" -vcodec libx264 -crf 15  -pix_fmt yuv420p mars-valley-2.mp4

#and for reverse,

ffmpeg -r 60 -start_number -3037 -f image2 -i "OpenSpace%06d.png" -c:v libx265 -x265-params lossless=1 zoom-in-to-psn-lossless.mp4

and today,

ffmpeg -r 30 -i "%04d.png" -c:v libx265 -x265-params lossless=1 bloodcells.mp4

and 

ffmpeg -r 30 -i "%04d.png" -c:v libx264  ../bloodcellsx264.mp4