portrait lens - perspective - question

[sarvi]

Hi
In search of a portrain lens for my Nikon D70 SLR. I have generally heard that lens between 80mm and 105 mm fixed focal length lens is good for portraits, and is supposed to give the photo a "tight perspective" as my friend called it. He was refering to his N80 and so was talking 35mm photography.

Nikon D70 is a smaller CCD and hence the lens seems to have 1.5(approx) multipcation factor.

So the 50mm lens would be 75mm on D70
and the 85mm lens would be around 125mm on the D70.

Does the "perspective get affected by the CCD size, i.e. should i use the multiplication factor when picking the right sized lens.

I have so far narrowed it down to the 50mm(f/1.4 and f/1.8) and the 85mm(f/1.8), based on the multiplication factor, which makes them 75mm and 125mm for the D70, close to the 85 or 105 that my friend recommended.

Questions:
1. Should I take into consideration the multiplication factor, or should I just be looking for an 85mm and a 105mm lens ignoring the mutliplication factor. Does the mutiplication factor affect "perspective"?
2. Between the 50mm(f/1.4 and f/1.8) and the 85mm(f/1.8), what would you recommend?
3. Does the multiploication factor affect working distance from the subject?

Any help is much appreciated.
Thanks,
Sarvi

[Peter_AUS]

Sarvi, yes use the multiplication factor when picking your lens as it will make a difference. I have a 50mm f/1.8 Canon lens with my 10D and that makes it a 80mm f/1.8 lens which can be a little more than I want for some occassions and find myself dropping back to my 28-135 f/3.5-5.6 IS Canon lens more to get a lens length of around 35mm which is around 56mm with the multiplication factor of x 1.6 that the 10D has.

Try lenses on the camera and then you will develop a feel for what you might want if you are looking for a prime lens. That is what I would do now.

[William Kazak]

Traditionally, the 85mm and the 105mm are your portrait lenses. On the D70 they would roughly correspond to 50mm and 85mm. If you are still using film, get the 85mm, it works fine for the D70 and would be a perfectly usable 120mm on that camera.
Recently, I bought the 105mm F2.8 Micro Nikkor AF. On the D70 it is a 150mm and boy, can I "jam" a face with that! I love it for portraits.
Another choice would be the 60mm Micro AF Nikkor. It would become a 90mm on the D70 and you could get really close on a face.

[Michael Fanelli]

Hi
In search of a portrain lens for my Nikon D70 SLR. I have generally heard that lens between 80mm and 105 mm fixed focal length lens is good for portraits, and is supposed to give the photo a "tight perspective" as my friend called it. He was refering to his N80 and so was talking 35mm photography.

Nikon D70 is a smaller CCD and hence the lens seems to have 1.5(approx) multipcation factor.

So the 50mm lens would be 75mm on D70
and the 85mm lens would be around 125mm on the D70.

Does the "perspective get affected by the CCD size, i.e. should i use the multiplication factor when picking the right sized lens.

I have so far narrowed it down to the 50mm(f/1.4 and f/1.8) and the 85mm(f/1.8), based on the multiplication factor, which makes them 75mm and 125mm for the D70, close to the 85 or 105 that my friend recommended.

Questions:
1. Should I take into consideration the multiplication factor, or should I just be looking for an 85mm and a 105mm lens ignoring the mutliplication factor. Does the mutiplication factor affect "perspective"?
2. Between the 50mm(f/1.4 and f/1.8) and the 85mm(f/1.8), what would you recommend?
3. Does the multiploication factor affect working distance from the subject?

The perspective and DOF of a lens is based on it's real focal length, not a "35mm equivalent" calculation. A 90mm lens will still be 90mm, the sensor merely crops the sides off just as you could do in PS. What changes is the angle of view.

If you want a 90mm portrait, use a 90mm lens and just stand back further. If you go to a 50mm lens, you will get the same effect as a 50mm on a film camera, again with the sides cropped off
.

[another view]

To add to what Michael said, focal length and angle of view are two different things. A 50mm on a D70 has the angle of view of a 75mm on a 35mm body. The perspective is that of a 50mm lens because that doesn't change regardless of if it's used on a DSLR, 35mm, medium format, etc. An 85 is probably a better choice if you have the working room to use it, but if you don't then a 50 would be a good second choice.