I have a Nikon D3300 camera. I am doing a project in which I have to project an image of uniform intensity value onto a white screen and take photo of it. This is actually the calibration part. But the problem I am having is that even when I go into manual mode, with fixed iso, shutter speed and aperture, the photo I take give me unpredictable intensity of the screen image. If I put 150 as the greyscale value, I have gotten values from 170 to 210. If I do 0, I get above 37 and below 97. I have captured repeated images for a single greyscale value, but never have I gotten a single output intensity for all the images.
my current settings are ISO:100, F14 and shutter speed 1/40. I have put ec to zero and white balence to AUTO. I am taking RAW image of the .NEF format, then converting them into .ppm by rawkit python module and then taking the intensity values from PIL(another python module. But I don't think that is relevent). I am triggering the camera from the laptop using gphoto, but I don't think it changes these settings that I have put manually in the camera. No matter what the abovementioned settings however, I am not getting the constant output. I have also set the zoom of the lens such that the screen covers the entire image and the background light fluctuations are not great. Also, the focus is on manual and flash is disabled.
Is there some setting that I am missing? Pls help...
Is there some settin