I already know that my circuit is the worst you could probably do.
The measurements i get with it with 100k anyway are really so near to what the measurements should be that i could actually work with that.
Just the light source im using for that now is so damm bright that it burns in the eyes ( big cob led plate) this generates a lot of heat and also i would need more sensitvity as i would need to have a lens on a camera and measure the time the automatic of the camera made at a given luminance.
So right know i can measure the shuttertime at 3 points and the time needed for each curtain to travel the 35mm film plane but with an extreme bright light and without a lens on the camera so i could adjust the shutter but not the exposure automatic @anon57585045