In my case, the more expensive the item, the larger the image.
For cheaper items, I use 400px X 600px images, multiples.
For stuff that crosses the $1,000 price tag, the image gets to be 1,000px X 750px. And not one, or two, but more than a dozen.
Cliackable.
That sends the viewer to a huge 3,072px × 2,304px image. If that isn't large enough, nothing is...
I also include a Youtube video, that gets the Google search crowd to Youtube, and that sends them to my eBay store.
Take a look at this listing, for a better idea http://cgi.ebay.ca/ws/eBayISAPI.dll?ViewItem&rd=1&item=120655801478&ssPageName=STRK:MESE:IT
I host my own images, and I use Picture Resize Genius ( http://www.pictureresize.org/ ), to both watermark, rename and resize pictures in bulk.
The pictures uploaded in eBay's picture gallery (the 12 free pics) are always the largest ones, so when buyers click on "enlarge", the resulting picture is large enough to completely fill the window.
Now, as far as quality of the Jpeg goes, you want to go with the lowest acceptable setting (I use 40 %).
This helps to keep down the file size, while still getting a large picture.
Also, you have to know your target customers.
For example, I sell truck and trailer automotive parts, those listings have small pictures, and are a lot more dialup speed friendly.
Police duty items get slightly larger pictures, as those guys tend to have faster internet speeds.
Really expensive items get huge pics, as whomever can afford to buy a $2,000 items in the industrial segment, most times has high speed.
In your case, Bernie, I think that your buyers tend to be upper middle class hobbyist, with high speed internet. I would certainly go with at least 700px x 520px pictures.
BTW, your pictures are really nice, with the neutral background and the shadow drop, they make your items "jump out " from the list. I hope your professional photographer impresses you, but frankly, you are doing a nice job already without him ...
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