Photos app destroying my photos

[Leerox]

Please can someone tell me what is happening? I was editing a photo (a prized astrophoto) tiff file and when i saved it the photo disappeared and i was left with this(image of different coloured horizontal rows) . Unfortunately when i first learned this i hadnt clicked save a copy so the original photo has gone which has really p@£)£d me off. Iv tried this editing on other photos and the same happens .? Please Microsoft tell me why and how to prevent this

 

[joss]

What are you using for editing of photographs ?

 

[Leerox]

All sorted now thanks., it was my graphics card needed update