Ok, we have signature tag for images signed by artist (well, not necessarily by artist, but it's one common usage).

What about imaged by eastern artists, "signed" with seals (stamps)? Do we have a tag for that?

I think that watermark doesn't apply (it would be really bad choice).

Well, it does look like there are some examples in stamp but the tag is awfully ambiguous at present. There needs to be separate unambiguous tags for (a) the object used to make the mark and (b) the mark itself, whether it's the artist's signature (which can be used in conjunction with the signature and artist_name tags) or a part of the image itself. For now, I'm thinking (a) seal_(object) and (b) seal_impression.

Going by wikipedia those stamps/seals are referred to as "inkan" or "hanko", so those might also be naming possibilities to refer to them (the object or the signature).

NWF_Renim said:

Going by wikipedia those stamps/seals are referred to as "inkan" or "hanko", so those might also be naming possibilities to refer to them (the object or the signature).

AFAIU "iknan" is generic term. We still would have to differentiate between inkan_(object) and "inkan impression" tags. (Might the second one be named just inkan?)
This article says something that hanko is used for documents, so I don't know...
Looks like gagō-in (gagou-in) (雅号印) would be more proper term.

The problem is the possible difference between encyclopedic definition, and how Japanese really use those terms in everyday life.

I just came across a picture from this search: logo kanon_(kurogane_knights), which seem to be mostly/all this rather than a logo. I went looking for an appropriate tag, but as mentioned here, the ambiguous stamp tag seems to be the closest.

There is a term specifically for the impression of a seal: in'ei (印影). So I'd recommend in'ei for seal impressions, and either inkan or hanko for the object, with the other of the two as an alias due to both being common.

Laethiel said:

I just came across a picture from this search: logo kanon_(kurogane_knights), which seem to be mostly/all this rather than a logo. I went looking for an appropriate tag, but as mentioned here, the ambiguous stamp tag seems to be the closest.

There is a term specifically for the impression of a seal: in'ei (印影). So I'd recommend in'ei for seal impressions, and either inkan or hanko for the object, with the other of the two as an alias due to both being common.

The artist logo tag is used to represent these stamps in some cases eg. wantan-orz artist_logo. Presumably that was the tag that was meant to be used, rather than logo which is meant for copyright or company logos.

I'm in favour of adding a tag specifically for seal impressions, but the question is should the artist logo tag be removed from these cases, or should they be used together? And if the latter, should the new tag imply artist logo or should it be dealt with on a case by case basis?