[recherche d'infos] Nikon process 240 mm

Citation

Apo-Nikkor and Process-Nikkor large format lenses
by Daniel W. Fromm
1 Apo-Nikkors, according to Nikon
Nikon made two families of Apo-Nikkor lenses, both intended to be used for, e.g., photoengraving.
These are, respectively, dialyte types (“Symmetrical Type Apo-Nikkor”) and Tessar types (“Asymmetrical
Type Apo-Nikkor”).
Nikon claims that all of them have low distortion (“almost zero” at 1:1) and are highly corrected
for three colors, (“red, green, and blue”). “The highest sharpness will be attained when the aperture is
stopped down by 2-3 stops from the maximum. When the aperture is reduced by 2 stops, a uniformly
bright image area will be obtained without vignetting at the corners of the image field.” “Even when the
aperture is stopped down, the image is maintained in the same position, so that focusing can be done at
maximum brightness.”
I have an old Nikon catalog that says this about the two types:
1.1 Symmetrical Type Apo-Nikkor
Each Apo-Nikkor of symmetrical type, consisting of a symmetrically arranged optical system consisting
of 4 groups and 4 elements of lenses, has the following features:
1. The lenses will give a wide effective picture angle (about 46º) for their long focal length. Therefore,
the image area being assumed the same, a camera of shorter length can be used.
2. Since the lens system is symmetrical in respect to the iris diaphragm, the optical performance
remains the same, regardless of the direction in which the lens is used. No need to reverse the
lens for magnification. This greatly facilitates the use of the lenses mounted on a camera with
automatic focusing device.
3. The lenses are also suitable for work, where no distortion is permissible at a reproduction ratio
close to full size. On the other hand, since the lenses give an excellent image, for a wide picture
angle at infinite distance as well as in enlarging work, they can also be utilized for a large size
camera or on an enlarger.
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Figure 1: Symmetrical Apo Nikkor lenses, dialyte type, focal lengths 305 and 420 mm
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Figure 2: Symmetrical Apo Nikkor lens, dialyte type, focal length 480 mm
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Figure 3: Symmetrical Apo Nikkor lens, dialyte type, focal length 610 mm
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Figure 4: Four Symmetrical Apo Nikkor lenses, dialyte type
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1.2 Asymmetrical Type Apo-Nikkor
The asymmetrical type Apo-Nikkor lenses are intended primarily for reproduction of Japanese and Chinese
characters. They have a rather narrow picture angle in order to attain highest resolving power. They
can also be used as reproduction lenses in electrostatic photography and microphotography, as enlarging
lenses for color and monochromatic photography, and in connection with general purpose cameras like
view-cameras and studio-cameras.
2 Process-Nikkors, according to Nikon
Nikon made four Process-Nikkor lenses, all four elements in four groups double Gauss types with minimum
aperture of f/32. Very similar – identical, but for the name – lenses were sold as Nikkor-Q before
the name Process-Nikkor was used. Nikon does not claim that these lenses are apochromatic and does
not recommend that they be used outside their usable range of magnifications.
I have a Nikon catalog that says this about them:
The wide picture angle design of Process-Nikkor lenses makes for larger subject area coverage than
obtained with conventional lenses at the same working distance. In addition, this distance can be reduced
for the same subject area, meaning the camera equipment can be compact.
Although the maximum aperture ratio is 1:10, these lenses have large diameters and minimal vignetting. . . 68° subject area coverage at full aperture or 74° coverage when stopped down to f/22.
Process-Nikkor lenses assure remarkable flatness of the image over the entire image area. They
provide quick and low-cost photoengraving for monochromatic reproduction.
The lens construction is 4 elements in 4 groups, and their configurations are symmetrical so they can
be used for either enlargement or reduction without reversing.
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Figure 5: Process-Nikkor or Nikkor-Q lenses, double-Gauss type, were supplied in a nice wooden box
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Figure 6: Nikkor-Q lens, double-Gauss type, focal length 260 mm; note the protruding rear lens element
of this particular design.
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3 Wide-angle Apo-Nikkors, according to Nikon
Steve Hamley very kindly shared a Nikon brochure on these lenses with me. The full text can be found
at: [www.largeformatphotography.info]
Nikon made four Wide-angle Apo-Nikkors, all six elements in four groups plasmat types with minimum
aperture of f/128. Nikon says explicitly that these lenses are apochromatic, "fully symmetrical,"
and that, although their published "usable magnification range" is 1:10 - 10:1, they "are equally suited
for other precision optical tasks, such as: . . . use with view cameras or large format studio cameras."
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f max mount weight
(mm) aperture type coverage (mm) (g)
150 f/9 tessar 45º 53x0.75 175
180 f/9 dialyte 46º 53x0.75 210
210 f/9 tessar 45º 53x0.75 185
240 f/9 dialyte 46º 53x0.75 220
300 f/9 tessar 41º 53x0.75 240
305 f/9 dialyte 46º 72x1 430
360 f/9 dialyte 46º 72x1 470
420 f/9 dialyte 46º 90x1 780
450 f/9 tessar 37º 72x1 550
455 f/9 dialyte 46º 90x1 810
480 f/9 dialyte 46º 90x1 860
600 f/9 tessar 37º 90x1 775
610 f/9 dialyte 46º 110x1 1450
750 f/9 tessar 37º 110x1 2015
760 f/11 dialyte 42º 110x1 1360
890 f/11 dialyte 42º 162x1.5 3600
900 f/9 tessar 37º 140x1.5 3570
1070 f/12.5 1600
1200 f/9 tessar 37º 213x1.5 8385
1210 f/12.5 dialyte 40º 162x1.5 3800
1780 f/14 dialyte 36º 213x1.5 6430
1800 f/14 tessar 35º 20’ 213x1.5 8860
Table 1: Summary of Apo-Nikkors’ characteristics
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Magnifif
max coverage mount weight cation
(mm) aperture type f/10, f/22 (mm) (g) (usable)
180 f/10 4/4 double Gauss 68º, 74º 62x1 350 1:4 - 4:1
210 f/10 4/4 double Gauss 68º, 74º 72x1 510 1:3 - 3:1
240 f/10 4/4 double Gauss 68º, 74º 82x1 730 1:2 - 2:1
(*) 267 f/10 4/4 double Gauss 68º, 74º 90x1 1070 1:2 - 2:1
(*) note: engraved 260 mm
Table 2: Summary of Process-Nikkors’ characteristics
f (mm) max type coverage mount weight (g) Magnification
aperture
150 f/8 6/4 plasmat 60º 53x0.75 240 1:10 - 10:1
210 f/9 6/4 plasmat 57º 72x1 455 1:10 - 10:1
300 f/9 6/4 plasmat 54º 90x1 840 1:10 - 10:1
360 f/9 6/4 plasmat 54º 90x1 970 1:10 - 10:1
Table 3: Summary of Wide-angle Apo-Nikkors’ characteristics
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