Nikon D3100 and Nikon AF-S DX Micro NIKKOR 40mm f/2.8G Lens?
I have very little idea about compatibility with SLR cameras, so I'm wondering if these will be compatible together. I need a lens that is good for close-up shots and this was the lens I found. If it's not compatible or you think I should change one of the two parts can you recommend me something else? My budget is £500. The camera will be used to take pictures of small (and sometimes moderately sized) artifacts to be listed on eBay and possibly used in other situations (hence I haven't gone for higher MP), but it will likely be used for close-ups on nature as well (but this is just a secondary aim). Any help is welcome or recommendations for whatever else I may need, specifically a flash, or light I can use which produces natural looking light would be helpful.
AF-S means the lens contains a motor.
DX means it's designed for cropped-sensor use.
G (gelded) means no aperture ring - you couldn't use it on as D3100 anyway.
This lens is therefore fully compatible with your camera.
Yes they are both fully compatible & will function together.
It will be fully compatible.
The D3100 needs AF-S for autofocus, and at least AI-P/AF for auto exposure.
Yes, that lens is compatible and that will be a perfectly good setup for macro close-up work. It is certainly the best you will be able to do with a £500 budget.
The only problem with the 40mm lens is that the short focal length means you have to physically get very close to the subject, so you can easily end up blocking your own light, so lighting might become a bit tricky.
Rather than buying a standard flash, a ringflash might be a better idea. While you won't be able to afford a good expensive one, for ebay items something like this would probably be good enough:
http://www.amazon.co.uk/...006T4UUN8/
If you can stretch the budget (quite a lot), I would recommend the Nikon 85mm DX Micro AF-S lens instead of the 40mm as the extra distance from the subject would make life much easier, and it is a much better and sharper lens.
An alternative budget stretch would be for the D5100. The higher resolution LCD screen (920k pixels on the D5100 but only 230k on the D3100) is much better for live-view and for reviewing pictures; plus it's much easier to take low-down pictures of small things with live-view using the moveable screen. Overall, the D5100 is a much better camera, if you can afford the extra: http://snapsort.com/...ikon_D3100
By the way, in case you didn't already know, there's £35 cashback on the D3100 or £55 cashback on the D5100 at the moment and £25 cashback on the 40mm DX lens; from Nikon here: http://www.nikon.co.uk/sites/cashback/offer-uk-nov12.html - but to get that make sure you buy from a UK stockist, not a grey importer like Pixmania.