When loading project files from version 0.8 the image is not undistorted correctly:  Apparently there were variables `k4`, k5`, and `k6` which were not present in more recent version, and got re-added with the extended model. Hence, the parameters occur in the pet-file and are read and stored correctly in the UI, but are used for undistortion when not needed. pet-file: ``` ... <INTRINSIC_PARAMETERS TY="-0.000557" K5="0" <--- should this be set loaded? QUAD_ASPECT_RATIO="0" FIX_CENTER="0" R4="0.049984" R2="-0.138423" ENABLED="1" TANG_DIST="1" K6="0" <--- should this be set loaded? R6="-0.037627" CY="1199.99" TX="-0.001076" K4="2" <--- should this be set loaded? FX="2611.68" FY="2607.88" CX="2058.2" /> ... ``` To reproduce: sime/export/Samstag/4k/*.pet