I presently have an 18-300mm lens that I use on my D7000 that gives me an effecive 27 to 450mm because of the crop factor. I plan to get a D800 but have not decided which lens(lenses) to purchase with it. I understand that if I use my 18-300mm lens on the d800, the d800 will automatically go into a DX crop mode. I know that the resolution wil be reduced to about 15mp. My question is does the crop factor still apply so that I am getting an effective reach of 450mm?