Considered cropping the images with the background etc Moco?...obviously not.
You take a Pic of a machine.....that needs in someway to be edited!..........try doing that twice!..........
So give this either some thought or practice and not just being a sheep by following some other suggestion, you'll see i'm right and its not really as straight forward as you say, I also still say RB's wrong too.
Off image, then its lit.........just how far will you go to clip the lamp image?.........won't the boarder be lighter?...lasso won't work here will it!
If you think it's so easy i'll gladly provide you with some images 
You think you are so cocky Moco.........but haven't any idea on this One fella.
Ady...... can i first just say im sure this post will be deleted or moved by you so il keep this post divided into sections so you can edit it rather that delete it.
I cant believe how stressed out you get over little things like this. Its really starting to get on my tits now Ady!! Before you post a reply to me try and think about whether its actually worth being rude to me or if your just pre menstrual at the time you posting ok fella.
Now...... back to the topic.
You take a Pic of a machine.....that needs in someway to be edited!..........try doing that twice!..........
Cropping two images or even having to edit two pictures which at the end result need to be the same really isnt that hard a task for someone who has developed even a small amount of knowledge for photoshop. It just really isnt ady and i would have thought you'd know that.
So give this either some thought or practice and not just being a sheep by following some other suggestion, you'll see i'm right and its not really as straight forward as you say, I also still say RB's wrong too.
Im not being a f*****g sheep ady im simply disagree with your opinion and you just cant handle it as usual. I think that with a good enough digi cam and tripod etc then this really wont be that big a task. i personally think that doing all the lamping
yourself will be better in the long run but thats not the point.
The point is with two identical images with one in a lit state and one unlit i think it wouldnt be any where near impossible to do, infact i think it would be quite straight forward if you know what you are doing.
Off image, then its lit.........just how far will you go to clip the lamp image?.........won't the boarder be lighter?...lasso won't work here will it!
Right, first of all the are ways to set up the camera to minimalise this as much as possible to make the task slightely easier.
Then using tools like the clone tool etc or even cutting and pasting certain sections of the other image to try and get rid of any unwanted light.
Might be a bit tricky but what im saying is with some patience this could be sorted no problem.
Also what you have to remember is that you only use one image for the backdrop.
so.......... if all else fails then that problem you mentioned could be very easily sorted with some good transparency work on the the lamps in paintshop pro!!!!! really not a hard task for anyone doing that tbh, just takes patience.
If you think it's so easy i'll gladly provide you with some images 
You think you are so cocky Moco.........but haven't any idea on this One fella.
Ady im not gonna do one just to prove you right im afraid. its a waste of my time trying to prove you wrong and i better things to do at the moment. But this isnt to say i couldnt do it...... im more than confident that i could.
And ady ffs..... im not trying to be cocky

Im just informing you that i dont agree. And tbh i have no reason to think that you really know what your talking about either on this one cos im not sure of your photoshop skills.