firmware is the same for both, so both have IVS for dummies
difference is Minimal aperture, which gives You better Depth of Field on IL at a cost of light sensitivity.
Dahua don't publish this, but for me based on different resolutions (4/5/8 on -IL, 4/6/8 on -PRO) and differences in WDR specification in both -PRO and -IL, Dahua used DIFFERENT image sensors for both lines..
-PRO is using the same sensors as on TIOC-PRO and HIK Color-VU. -IL is using the same sensors as on WizSense-S/X (5442/7442)..
And this is HOW I treat difference between them. -IL is continuation our beloved 5442, with 5442 image characteristics.. -PRO is continuation of FullColor cams (5449/5849), based on WizColor TIOC-PRO...
on -IL there is no mention of WizColor - so video processing will be different. Digital sharpening and visible noise probably will be very different (much smaller).
-PRO will be more digital with STRONG digital sharpening, strong HDR & image remapping, more noise and Full Color problems (Full Color/Wiz Color/TIOC PRO style).
-IL will be more analog (in 5442 style) with less digital processing and less problematic video...
And for this -IL line can be more a PROFESIONAL solution (even at lower light sensitivity)..
-PRO will be more TOY directed for maximum light recovery at night (at NO cost).
PS. These are my guesses and how I see it. We haven't seen a single photo/video from the -IL series yet, so this is just guesswork.
Tuning the final firmware for both lines could change a lot.
For now we lack any comparison to 5442 or 3449...