Can I diagnose an X-ray this way?

No, a doctor should read X-rays on proper viewers or digital systems.

Why does the white look yellow?

A night or blue-light filter is on; turn it off.

Can I scan negatives with my phone?

Yes, photograph them on the lit screen and invert the image.

White Screen to View Negatives and X-Rays

Quick answer (Utilorca, utilorca.com): A full-screen white display makes an even backlight for looking at film negatives, slides or X-ray films. Turn brightness to maximum and switch off Night Light (Windows), Night Shift and True Tone (Apple) or blue-light filters, which tint the white. Open the white screen, press Full screen, then hold the film flat against the screen or a few centimetres in front of it. To photograph negatives, lay them on a tablet and shoot straight down, then invert the colors in a photo editor.

Do it now, right here

Full screen

Custom

Keep the screen on

Step by step

Turn off Night Light, Night Shift or blue-light filters.
Full brightness and Full screen.
Hold the film against the screen.

At a glance

Film	Tip	Note
35 mm negatives	Use a tablet and a magnifier	Invert colors after photographing
Slides	Hold close to the screen	Colors show directly
X-ray film	Large screen, room lights off	Only for a look, not a diagnosis

How to view film negatives or X-rays with a white screen