Re: lens question, apo ronar 240
Hi !
You can't go wrong with any apo ronar provided that the lens is clean, fungus-free and that the shutter operates perfectly.
At the origin the apo-ronar was used for repro and copying work. It is a 4 element lens, perfectly symmetrical and its correction is the best in principle at the 1:1 ratio. Some apo-ronars however were designed for a specific repro benches and were at their best at 1:5 or 1:10 ratio, but you do not have to care for this.
The lens is so good when stopped down to its operating f/number of 22 that you can use it at any distance even at infinity.
The only limitations of the apo ronar are
- it covers only 42° of field angle at infinity, the focal length of 240 mm will allow you to cover the 5x7" format (diagonal 210 mm).
- its maximum aperture is only f/9, hence you should care for parasitic light falling from behind when focusing on the ground glass. But the contrast of the image is so good that if you have no parasitic light it is not difficult to achieve the best focusing visually with a loupe.
- bellows draw at infinity is close to the focal length, this is not a telephoto design. So for landscape use in terms of bellows draw you'll require a minimum of one focal length plus a 10% margin, this makes about 270 mm, slightly more that 10 inches.
The advantage of a lens design like the apo ronar with no cemented doublet is that even older lenses of this kind will never suffer from lens separation or balsam failure!
Among vintage lenses, the apo ronar is one that easily outperforms many other more recent lenses, provided that you accept the minimum f-number of f/9 and require only 42° of angle.
Regarding portrait use, the focal length has no influence on perspective rendition, only on the actual framing for a given lens to sujet distance. Lens to subject distance is the only parameter that determines perspective rendition. Hence for a classical portrait, it is recommended not to be too close to the subject.
The 240 mm focal length will be perfectly OK for portrait work in 4x5" or even in 5x7", depending on how tight your portraits are.
To give you an idea of the required bellows draw and space for a portrait session with a 240 mm on the 4x5" format, here are a few examples
Framing a 20" by 25" (50 by 60 cm) subject on a 4x5" film corresponds to the 1:5 magnification ratio, the total bellows draw will be (1+0.2) x f = 1.2 x 240 mm = about 290 mm close to 12". The lens to subject distance will be (1 + 5) x 240 = 1.4 metre close to 5 feet this is OK for a classical portrait.
Framing a 20" by 25" (50 by 60 cm) subject on a 5x7" film corresponds to approx 1:4 magnification ratio, the total bellows draw will be (1+0.25) x f = 1.25 x 240 mm = 300 mm = 12". The lens to subject distance will be (1 + 4) x 240 = 1.2 metre close to 4 feet this is probably the limit (too close) for a classical portrait.
Framing a tight portrait of subject size 8x10" (20x25 cm) on a 4x5" film corresponds to the 1:2 magnification ratio, the total bellows draw will be (1 + 0.5) x 240 = 360 mm = about 1 foot 2 inches. The lens to subject distance will be (1 + 2) x 240 = 0.72 metre close to 2 feet 4 inches, this is usually considered as much too close for a "non-distorted" classical portrait.
And regarding close-up, the apo-ronar was designed for this but beware of the bellows draw that you'll need!
At 1:1 ratio on the 4x5" film format you'll cover ... an object of 4x5" size and your bellows draw will be 240x2 = 480 mm close to 19" !
At 1:1 ratio the image circle will be about 2x the image circle at infinity. Hence you'll even be able to cover the 8x10" film format from a 8x10" object. This, in principle: macro work in LF requires to be very careful about vibrations, since the camera + bellows becomes a huge "flexible" machine prone to vibrations.
At 1:1 ratio the depth of field is shallow but does not depend on the focal length.
Good luck!