Ummmmm...I don't know what makes it a "thumbnail"....usually, that seems to be a .png, and after left-clicking becomes a .jpg. The .jpg is a highly efficient use of kb, it seems, .png not so much. No, I really don't know how that works! But I used to run our club's website in html code, even though I've never stayed at a Holiday Inn Express. If you see somebody recommend "IrfanView" freeware, they are onto something good!

The one picture in the 1/2a forum (prop-rod thread) was fine, but the last two were simply
too small. Not only in file size, but physical size. Get your pictures to about 500 to 850
pixels wide. I normally will compress a picture in that size range to under 100kb. The file size is
very much affected by the crap in the background...blades of grass, rough concrete, lovely wood grain, course fabric, etc. suck up a lot of kb's, when what we're really interested in is the details of the model or engine.
There's a pretty good discussion of how to post pictures up in the Administration Forums (one of the top three group). It would be cool if a short and brutally clear "How To" could be posted and "pinned", but AFIK, that's not happened. Part of the problem is that there are several ways to do it. You can post a photo to SH, or you can put it in "PhotoBucket" or similar, and just link to it. Both ways have advantages and disadvantages. The ones that are on a site like PhotoBucket seem to go away after a few years...I guess the photo owner's bucket gets full and they have to make room for new ones. It really messes up a topic on SH or SSW when the pictures are gone. But then the Forum Owners Association has to cough up more $ for all the storage, a problem!

Steve