Found cool article about alt for image
I found an insightful article by Adrian Roselli about the proper use of alt text for images. The key takeaway is to keep your image alternative text brief, devoid of special characters, empty of URLs, and ideally in one language. Read why here.
In the article you can find examples how screen readers work with long alt. Spoiler: differently and in case of long text - not very convenient for user.
The coolest part is that Adrian Roselli has also prepared a decision tree to help determine what text should go in the alt attribute. It’s a series of questions where you select your option and get recommendations accordingly. Check it out here.