Where is the ambient light sensor?

I have seen no evidence that there actually is an ambient light sensor 

Edit to add:

Obviously, I had not been paying close enough attention to the fluctuation in display brightness in varying ambient light conditions.

There is definitely an ambient light sensor, but I don't know where it is located...

Sorry for any confusion.

I believe there is. There's defnitely difference in brightness when going upstairs in a dark hall vs. standing outside in the sun. Even in bright light I can see the difference.

From this support article https://support.garmin.com/en-GB/?faq=SYHHBWNgOL2oz1ZJYiV8L6&partNumber=010-02582-10&searchQuery=light%20sensor&tab=topics

Usage Factors That Impact Battery Life

• The epix (Gen 2) uses an ambient light sensor to automatically adjust the display brightness to an acceptable level depending upon the level of ambient light. Using the watch outdoors in bright environments may reduce battery life.
• Changes to the default display settings can significantly impact battery life. Higher screen usage will generally result in less battery life.

I wonder if it’s under the display because it seems to react even when only a small part of the screen is exposed to light, in which case hopefully solar is coming at some point.

Another implication is that having the watch under a sleeve (which I generally do) will make a difference in battery life

But why do you mark all of your posts with the "suggest an answer" tag, while most of the time your replys don't help? (For example right now.)

Gergely said:

But why do you mark all of your posts with the "suggest an answer" tag, while most of the time your replys don't help? (For example right now.)

Why did you down vote my post AFTER I corrected it?

Back at ya 

Because it still shows as an answer to the question...

Gergely said:

Because it still shows as an answer to the question...

Because at the time of my original post, it was an answer - albeit later found to be in error, I let it stand as originally posted (with the correction edit, of course).  No reason to rewrite history.

Edit... Untick... Save...

To tell you the truth, it is very annoying to open a topic with big hope that there will be a correct answer to the mentioned "problem" and after that seeing that it was just you (again)...

Gergely;  At the risk of stepping in between you and Gaijin, and not knowing what history might exist between you to, I for one have found Gaijin’s posts very helpful over on WUS and here, regarding Garmin watches. 

As for having your high hopes dashed for an answer on a forum, with respect, that sounds more like a personal problem.  Let’s face it, most threads on any forum, talking about almost any topic, rarely end with a definitive answer.  It’s the reason threads go for pages and pages. 

I’d agree that this question should have a high likelyhood for a clear answer.