A relatively simple way to get the positive effect of negative film is to scan the original photo into a computer and print it with an inkjet printer with film printing function (such as Epson R230).

After the original image is inverted, there will be great distortion, especially the color.

You can also remake it directly with a reverse film. There are not many places to develop reverse films now.

Taking a computer screen, the effect should not be very good. It is better to print out the photos first, pay 6 inches 1 yuan, and remake the photos in the sun, and the effect is guaranteed.

If you must shoot the screen, you can fix the camera on a tripod or a fixed platform and use the aperture first. The aperture should be set at 5.6, and the sharpness should be enough. It doesn't matter if the shutter is slower.