This has plagued me for years and I have chopped and changed the way I photograph my artwork, the way I show it and this has meant redesigning my main art website repeatedly over the years. I have always quite liked th eway flickr shows images, large and clear. Fine Art America is also good.
One of the things that should not be a problem, but is, is having your images stolen. It has happened to me a couple of times now, the last time tey took the trouble to photoshop my watermark out before making my artwork available to buy on the side of a mug!
I have now reverted to scanning. This can't be done for large paintings but much of what I have been working on recently has been smaller scale, more detailed pencil work and this lends itself quite well to scanning.
I recently completed a coloured pencil drawing which is approximately A3 size.
This was the first shot.
This was taken with my iPad, which can usually be good enough without photographing using My Canon Eos 350D which is what i use for making prints.
i realised this was pretty awful and so took a shot with my iPhone, which I have had really good results from in the past. Certainly accurate enough for my website. This was the result.
Utterly awful with regard to colour but it did pick up some of the pencil work, which took a long time to create.
Finally, I scanned the artwork and stitched it together electronically as it was too large for my scanner.
This was the result:-
Very close to the original and the detail in the pencil work is clear to see. So, for drawings from now on, it will be scanning rather than photography. Another small step forward.