Portrait Lens on Toyo 5x4

[Ed Moss]

After a couple of hours of research I'm still no closer to an answer.
What lens will give me a tight headshot on my Toyo 45aii max bellows extension of 324mm (http://www.toyoview.com/Products/45AII/45AII.html)
I've got a 240 but can't get close enough, my 150mm is a bit too close for comfort.

Can't decide if a 210mm or 300mm will do? Or would a top hat on my Fuji 240 do the job?



Regards
Ed

[Peter B]

I'd say the 300mm would be the better bet if we assume that 150mm is the "standard" lens for 5x4. Doubling the 150 to 300 should be roughly equivalent to doubling the 50mm to 100mm on 35mm, or doubling the 80mm to 150mm on 120, so reasonably close to the portrait lenses in these formats. The problem with the 210 is that it is only about a 70mm on 35mm, which is really a bit too short for a head & shoulders.

[Matt_Bigwood]

Hi Ed

I don't know if you're after a modern lens, but I have a 203mm coated Kodak Ektar from the 60's which I have used on my MPP for tight portraits. The lens covers up to 5"x7" and my example at least is very sharp with good contrast.

Matt

[IanG]

You'd really struggle with a 300mm as you don't have enough bellows extension for much closer work..

A 210mm or better still a 240mm would be far more practical, however if you can't get close enough with a 240mm then you need shorter not longer focal length lens so try a 210. I've left my 210mm Symmar in Turkey or I'd have lent it you to try as I'm not far from you .

Ian

[Ed Moss]

Thanks all,

I know someone with a 210mm so I'll give that a go first an see what perspective it gives me.
Matt have you any examples you can post of the 203mm?

Regards
Ed

[gary mulder]

A Fujinon T 1:8/ 300mm needs 290mm bellows extension to focus 1,4 m from the lens. Other telephoto designs will do similar tricks.

[Thingy]

If you use a small lens such as the Nikon 300mm, mounted in a Copal 0 shutter, you can use a "top hat" assembly. If you go for the Ebony Standard Extension panel Set '0' or '1' (to accomodate Copal series 0 and 1 shutters) it will set you back £125 + VAT, but will give you an extra 35mm extension. You could add a 17mm extension to that to give you 52mm total extension, but if you add more tubes you risk occluding the image.

linky: http://www.robertwhite.co.uk/product.as ... &PT_ID=163

Alternately you might want to consider Schneider's 350/11 Apo-Tele-Xenar Compact which weighs only 400g and is mounted in a Copal 1 shutter.
http://www.robertwhite.co.uk/product.as ... &PT_ID=370

Long lenses gives you better depth of field, but as you want the lens for portraiture, a telephoto would do, though they weigh a lot more than the Nikon 300mm!

[Emmanuel Bigler]

Hello from France !

it is not difficult to make some back-of-a-virtual-envelope calculations to roughly predict the total bellows draw required to frame a tight portrait. I say : "virtual envelope" since we'll not compute anything at all except mentally estimate some rough values No math required ! If you can mentally convert inches into millimetres (and vice-versa) or can mentally covert used LF lens prices labeled in Euro or Dollars into Sterling Pounds, then you are all set for what follows

If we consider in the 5x4 format that we need to reach the magnification ratio M=1:2 = 0.5, it means that we'll be able to frame a subject of size 10x8 inches i.e. 250x200 mm. This corresponds to a tight portrait.

For a given magnification factor M = (image size)/(object size), the additional bellows draw or bellows extension "ext" beyond the focal point (where images of far distant objet will focus sharp) is
"ext" = M . f
where "f" is the focal length in use; the formula is valid for all lenses whatever their design might be.

The other information needed is the flange focal distance which is proper to each lens.
For quasi-symmetrical lens like an apo-symmar, apo ronar, etc.. i.e. anything which is not a telephoto, the flange focal distance is close to the focal length;
hence with such a lens you need about 1.5 times the focal length in order to reach the magnification ratio M=1/2 = 0.5
If the total bellows draw is 324 mm, the max focal lengh for a symmetrical lens design @M=0.5 and (f+ext)=324 is 2/3 of 324, i.e. 2x108 = 216mm say 210 mm.
in this situation with M=0.5, the distance between the subjet and lens is f(1+1/M) = about 3 f = 610 mm. This is probably too close for a traditional "respectful" portrait ; howerver, for a record cover of a traditional & "so British" Rock-Pop Group of the last century, I would suggest getting much closer if possible

now we are left with the hard rule of photographic perspective : perspective rendition is independant of the focal length, only the placement of the lens (actually : the distance to the entrance pupil) defines the projection of a 3-D object on film. The choice of a suitable focal length will of course define the external frame in the final image.

Now consider a 360 tele arton lens ; I own one and I'm very happy with it. Its flange focal distance is 210 mm.
At M=0.5, the additional extension "ext" will be about 360/2 = 180 mm. Plus 210 of flange focal distance makes a total bellows draw of (210 + 180) = 390. Still too much for a maximum of 324 ; hence let's take it the other way : 324-210 = 114 = ext = Mx360 hence M = about 1/3 is the closest we can reach.
With 324 mm of total bellows draw, our brave Toyo and our brave tele arton will allow us to reach M= about 1/3
The object frame will be 3x4 by 3x5 inches i.e. about 300x370 mm. distance to the subject will be f(1+1/M) = 360x(1+3) = 1,44 metre ; this is more acceptable for a "classical" portrait.