I am new to petzval lenses. I have a project in mind that would benefit from the classic 'petzval effect'. For the project, I want maximum ‘swirliness’ (is that even a word?) for the out-of-focus areas. Most of my images will be made of subjects ~30 feet in front of me, outdoors. I will use a 5x7 KB Canham camera with film. Most of the images will only have little to moderate movements. I would expect that petzval lenses that cover considerably more than 5x7 will have a sharper center and not as much swirly bokeh until the image reaches the edges of the coverage, and for this reason I am thinking I want a petzval lens that just covers 5x7 with a little bit of movement allowed at subject-to-film distances of 20 to 40 feet and wide-open aperatures. In addition, I want to do long exposures, so I will need a method of adding ND filtration either at the front, back, or waterhouse stop area of the lens. How does one gauge or rate the ‘swirliness’ of a petzval lens? Thoughts on the petzval lens category or design that would best fit my particular needs?

Any advice here appreciated ... apologies if this has already been covered ... please point me to earlier posts. THANKS!