Can Duergar See Through Stone normally?

[Reduxist]

I'm planning on making a Duergar ranger as an enemy for a story I'm planning. To summarize his character, he's a warden overseeing a ton of slaves that are in the process of making tunnels between Arcadia and Garund underneath the Arcadian Sea. He is assisting this by also working as an engineer and helping scope out whether a wall is safe to dig or not. To do this, he (as well as his fellow Duergar lackeys) would mainly cast See Through Stone to see if there were hazardous materials such as lava, ocean water or monster nests behind certain walls. This also helps with hunting down any runaway slaves that try to hide in the tunnels.

My question stems from a description of the See Through Stone spell.

See Through Stone wrote:

You see within the stone as if you were looking at the area in normal light, even if there is no illumination, though low-light vision and darkvision have no effect on your ability to see through stone.

Considering that Duergar have light sensitivity, will the above detail affect their vision and negatively impact the whole purpose of the spell?

[toastedamphibian]

No, light sensitivity shouldn't matter here for a few reasons.

1. Light sensitivity is triggered by Bright Light, this is as "normal" light.

2. It is not actually making light, just letting you see as if there was. Probably not enough to cause a problem.

3. Even if it was bright light, and did bother them, dazzled would just give them -1 on perception checks. It would still be useful.