Image sitemap question?

Question

Search Engine Optimization

The question of such a plan, I am doing a sitemap for images for the site.

<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:image="http://www.google.com/schemas/sitemap-image/1.1">
<url>
<loc>http://site/products/chasy_pioner_11_kamnej_sssr</loc>
<image:image>
<image:loc>http://site/files/products/IMG_2057.800x600w.JPG?adef4004e3c11cab571715e6d2200216</image:loc>
<image:title>часы пионер 11 камней СССР</image:title>
</image:image>
<image:image>
<image:loc>http://site.ru/files/products/IMG_2058.800x600w.JPG?8b22cdf1521f28bfa3c26d533306fa87</image:loc>
<image:title>часы пионер 11 камней СССР</image:title>
</image:image>
</url>
</urlset>

The question of such a plan is whether it is necessary to set
each

lastmod
priority

And how important is this for the image sitemap?

Answer 1

whether to set ... Each ... lastmod, priority

No. Required tags are <image:image>and<image:loc>

And how important is this for an image sitemap?

I believe that if these tags are applicable, then they work like in a regular sitemap - they give "hints" to the robot what to pay attention to in the first place.
"If" I wrote because I don't see them in the specification at all. In addition to the tags above, there are caption, title, license, and geo_location.

Answer 2

unimportant,
but lastmod can be put in just about anything