Portrait lenses for close model photography?

I have seen some photographer have their model kneel, and then the photograph gets really close and angles the camera and lens upwards to models face. My question is, what is an affordable lens that can do that? I use a D90 Nikon, so am happy to hear about lenses from tamron and Sigma, plus other makes for Nikon camera.

Depends on your skills of a photographer…

35mm f/1.8, 50mm f/1.4…

all lenses are affordable… But it depends on your budget…

Wide angle lenses (35mm and less) used close to the models face will distort their features, anything coming towards the camera (noses chins etc) are exaggerated, it's not a technique I would use often, but it may be the effect the photographer was after.

The 'nifty fifty' (wide aperture 50mm) with your cameras crop factor has the same angle of view as a 75mm lens has on a full frame camera, this focal length is ideal for non distorting portraiture, but you will be further from the subject. The wide aperture is useful for those 'selective focus' shots where the subject is in focus, but the background burred.

Affordable lens is the question! I do a lot of work with model portfolio work and I use 2 main lenses with my Nikon D700, D3S or my D7000 depending on what I'm attempting to do.

1. Nikon 85mm 1.4
2. Nikon 70-200mm 2.8 VR II

Both are very expensive glass but work very well. I would invest in the Nikon 70-200mm f/2.8 first. It would work the best for your Nikon D90 DX camera. This zoom range will allow you to zoom in close to your model! Sigma's EX line has come a long way in the past couple of years and they are almost half the price of Nikon! Sigma's 85mm 1.4 is amazing and sharp! But it's meant for a Full Frame Camera. Remember, it's not all about the equipment that you use, but you also need the creative eye to create the image.