UCanvas::DrawItem results in darkened image

[Servelat]

I am trying to draw a material on a HUD canvas using FCanvasTileItem.

Material:

The drawn image, however, slightly differs from the texture used:

(The result drawn in game is on the upper picture, texture asset is on the lower one)

I tried to change DrawColour of Canvas as it was suggested [here][3], but it did not help.
Both Default Lit and Unlit shading models give the same result. Fiddling with material settings and FCanvasTileItem properties does not fix it either.

What can be the cause of such behavior and how can it be fixed?

Thanks for help in advance!

EDIT: The same thing goes for DrawMaterial and DrawMaterialSimple Blueprint nodes

EDIT2: The issue seems to go away if i uncheck sRGB parameter in texture. Can anyone explain, how it works?

[Servelat]

Ok, so the whole issue was with the sRGB flag on a texture, which defines gamma correction. Confusing thing was that the official documentation recommended using textures with sRGB set to true for all diffuse textures by default. However, rendering with HUD Canvas is somewhat different from the world - sRGB textures appear darker, the ones with the flag unchecked are displayed as they should be