metallissimus wrote:I guess different "title" and "alt" tags are just another possibility to use a wider range of (key)words and diversify the wording a little bit. Like with a site's title and meta description – the former is a very concise description of the site's content whereas the latter is more detailed.
Yes, but a page's TITLE and DESCRIPTION are two very different but important attributes. Title is the most important SEO tag, while DESCRIPTION is irrelevant to SEO ... However, description will decide what shows when sharing a link on social media, and will also display in the SERP in Google search (below the title and url). Image ALT on the other hand, does not have much emphasis (relatively speaking), and it's unclear what emphasis it has and for what. The image TITLE is ONLY X3, and is not even a tag, so why not use the content of title to populate the ALT attribute? You are not diversifying anything by having different title and alt tag, and even if you were, how would you know diversifying and making TITLE and ALT different is a good thing for seo?
Just to be clear, when I speak of TITLE, I mean the X3 image title, which may display as text on the website. I am not speaking of the optional <img> title attribute, which is used for tooltips on mouse hover, but which is irrelevant to SEO.
mjau-mjau wrote:Honestly I don't know which ranking benefits the most from well SEOed images.
I think perhaps ALT tag has most effect to improve ranking of a PAGE where the image is embedded, if the image(s) on the page relate to the page's surrounding text. In other words, an image with alt tags alone (for instance X3 gallery layouts), does not really mean much. This seems to be the case from reading Google's own article on ALT tag, which also seems to recommend human-readable alt tags:
https://support.google.com/webmasters/a ... e-alt-text