My dad has been doing professional photography for 35 years (and plays guitar too) so I'll try to ask him about that.
Camera setup can be a little hard if you don't know your way around because every camera is different.
If you don't have access to spotlights, exterior lighting is always very good. The easiest time to take pictures is when the sky is a bit gray with no sun light blasting everything. Of course, you don't want to be facing the sunlight either because it will do something like this: http://www.art-logic.info/annecy/IMG/jpg/bouquetin-contre-jour.jpg
Then you can always setup a solid color blanket under and behind your guitar to subtract any distracting elements from the background (or not if you're a pool shot lover
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).
A little reflection on the guitar finish is always good to show a super nice gloss, but try avoiding any kind of object reflections.
The best way to get a good shot is to take a lot of them. Try different settings with both your camera and the placement of the guitar versus light to get the best light exposure as possible. Ideal exposure is when the object has enough whites without light blasting, and enough blacks without loosing details in the shadow.
Some example:
Overexposed shot (light blasted): http://www.lakedistrictdesktops.com/photography/images/over-exposed.jpg
Underexposed shot (all details are lost in the shadows, common with contre-jour shots): http://images.trustedreviews.com/images/article/inline/4640-Toodark01.jpg
Good exposure: http://i35.photobucket.com/albums/d152/sunnycarey/c8e296e9.jpg
About composition, its a good idea to take a centered frontal shot of your guitar so it's easy to see all the components. The important thing in frontal shots is to
get at the same level as your guitar, so position your body before taking a picture.
If you want to show more of the finish, try taking more dynamic shots. 3/4 views is a good way to do it. They key to more dynamic shots and better composition is to not have everything too centered, but spread across the whole picture in a pleasant way. Though it's very easy to reframe your shots in Photoshop to rearrange the overall composition.
Dynamic shot example: http://www.linternaute.com/photo_numerique/prise-de-vue/photo/30-exemples-de-beaux-cadrages/image/composition-dynamique-505991.jpg
Same shot but I highlighted some strong lines: http://www.picsend.net/images/252897stonglines.jpg
For close up shots, you will need to explore with your camera a bit more to get a good depth of field feeling. So adjust your focus to get a certain area of the guitar clear and the rest more blurry.
Example: http://www.linternaute.com/photo_numerique/prise-de-vue/photo/30-exemples-de-beaux-cadrages/image/composition-dynamique-505991.jpg
So to summarize:
-Good lighting conditions
-Avoid background distractions, the guitar is the star
-Find the sweet spot between overexposed and underexposed
-Be always aware of the position of the guitar in the frame for better composition results
-One of the most important thing is to take A LOT of shots, no excuse now with the numeric age
Hope that helps a little, I'll still try to get my dad's opinion on this.
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ccasion14:
Edit: if there's something that's not covered just tell me