This is just a small warning to you all: Study and research what you are going to shoot, just to make sure everything is done properly. This will make your images more saleable!

Here is an example:

I have played clarinet (a musical instrument) for a long time ago. Some time ago I searched for clarinet images to find gaps in collections that I was planning to fill. I got surprised how many crappy shots there were, images where the instrument and/or the action looked totally silly (unintentionally). Here are some examples (from 323 results at Getty's):

Hands (left/right) are the wrong way:
http://www.gettyimages.com/detail/104821717/OJO-Images
http://www.gettyimages.com/detail/108313623/Vetta
http://www.gettyimages.com/detail/84049748/Photographers-Choice
http://www.gettyimages.com/detail/78722497/Fuse

What are they doing?
http://www.gettyimages.fi/detail/96389322/Cultura
http://www.gettyimages.fi/detail/88798525/UpperCut-Images

You can't play clarinet wearing gloves:
http://www.gettyimages.com/detail/LS000837/Photodisc
http://www.gettyimages.com/detail/71078879/Stockbyte

I have no idea how they have managed to assemble the instrument so wrong
http://www.gettyimages.com/detail/99276468/Tetra-images
http://www.gettyimages.com/detail/57443016/Stockbyte

This is a mirror image:
http://www.gettyimages.com/detail/87854228/Dorling-Kindersley

The moral of the story: Spend some time researching your subject and/or get someone that is a specialist on the subject to be a "technical advisor". Otherwise the images may look silly to the trained eye.

Do you have more examples on other subjects?

What are they doing?
http://www.gettyimages.fi/detail/96389322/Cultura

Gotta be impressed that they got a PR from the clarinet manufacturer, though.