Distagon T* 2,8/25 ZF
Features
x
x
x
x
x
x
x
Low close-range adjustment (6 cm / 2.4")
from object to front lens surface
Optimal control of flare and stray light
Precise manual focusing
Robust full-metal construction
Identical color reproduction of all models
assures the quality of products measured
by hue difference
For industrial cameras with F-Mount
up to sensor sizes of 24x36 mm.
Mounts and optical coatings can be
modified on request
10/09 · Subject to change.
W W W. S T E M M E R- I M A G I N G . C O M
ZF-I: Industrial Edition
Features special screws to
fix focus and aperture
settings also in rough
situations.
ZF-IR: Infrared Edition
Features special coating for
optimized performance in
near-infrared applications.
Camera Mounts
Available for other camera
mounts such as EF, K or
M42 screw mount.
Carl Zeiss AG · www.zeiss.com/lenses4industry
Distagon T* 2,8/25 ZF
Technical Specifications
Focal length
Aperture range
Number of elements / groups
Working distance (object to sensor)
Angular field* (diag. / horiz. / vert.)
Max. diameter of image field
Flange focal length
Coverage at close range
Image ratio at close range
Filter-thread
Length (without caps)**
Diameter
Weight
Camera mount***
25 mm
f/2.8 – f/22 (1/ 2 stop intervals)
10 / 8
0.17 m (0.56 ft) – Ð
80 / 70 / 50°
43 mm (1.7")
46.5 mm (1.8")
55 x 83 cm (22 x 33")
1: 2.3
M 58 x 0.75
66.5 mm (2.6")
64 mm (2.5")
480 g (17 oz.)
ZF (F bayonet)
* referring to 35 mm format
** from bayonet mount to filter thread when lens focused to infinity
*** other mounts available on request
10/09 · Subject to change.
W W W. S T E M M E R- I M A G I N G . C O M
Carl Zeiss AG · www.zeiss.com/lenses4industry
Distagon T* 2,8/25 ZF
Relative Illuminance
E [%]
100
The relative illumination shows in percent
the decrease in image brightness from the
image center to edge.
80
60
__ f-number 2.8
… f-number 5.6
40
20
0
0
5
10
15
20
u'[mm]
Relative Distortion
V [%]
3,0
The relative distortion shows in percent
the deviation of the actual from the ideal
image height.
2,0
1,0
0,0
-1,0
-2,0
-3,0
0
5
10
15
20
u'[mm]
10/09 · Subject to change.
W W W. S T E M M E R- I M A G I N G . C O M
Carl Zeiss AG · www.zeiss.com/lenses4industry
Distagon T* 2,8/25 ZF
MTF Charts
MTF [%] k=2.8
100
The Modulation Transfer (MTF) as a
function of image height (u) and slit
orientation (sagittal, tangential) has been
measured with white light at spatial
frequencies of R = 10, 20 and 40
cycles/mm.
80
60
40
20
0
0
5
10
15
u' (mm)
20
f-number 2.8
__ Saggital
… Tangential
MTF [%] k=5.6
100
f-number 5.6
__ Saggital
… Tangential
80
MTF (%)
60
40
20
0
0
5
10
10/09 · Subject to change.
W W W. S T E M M E R- I M A G I N G . C O M
15
u' (mm)
20
Carl Zeiss AG · www.zeiss.com/lenses4industry
Distagon T* 2,8/25 ZF
Depth of Field
Object distance 1.00 m (3.28 ft)
0.91 – 1.12 m
(2.98 – 3.67 ft)
0.87 – 1.18 m
(2.85 – 3.87 ft)
0.83 – 1.27 m
(2.72 – 4.17 ft)
0.78 – 1.45 m
(2.56 – 4.76 ft)
0.72 – 1.75 m
(2.36 – 5.74 ft)
0.64 – 2.77 m
(2.10 – 9.09 ft)
0.57 – 10.00 m
(1.87 – 32.81 ft)
O-ZEIO6-09/2013 ∙ Subject to technical change without notice. No liability is accepted for errors which may be contained in this document.
Aperture
f / 2.8
f /4
f / 5.6
f/8
f /11
f /16
f / 22
Field range
Object distance 3.00 m (9.84 ft)
2.22 – 5.00 m
(7.28 – 16.40 ft)
2.00 – 6.00 m
(6.56 – 19.68 ft)
1.77 – 11.00 m
(5.81 – 36.09 ft)
1.51 m –Ð
(4.95 ft –Ð )
1.28 m –Ð
(4.20 ft –Ð )
1.03 m –Ð
(3.38 ft –Ð )
0.84 m –Ð
(2.75 ft – Ð)
W W W. S T E M M E R- I M A G I N G . C O M . I M A G I N G I S O U R PA S S I O N
GERMANY
AU ST R I A
10/09
Phone: +49 89 80902-0
info@stemmer-imaging.de
UNITED KINGDOM
FRANCE
Phone: +44 1252 780000
info@stemmer-imaging.co.uk
Phone: +33 1 45069560
info@stemmer-imaging.fr
IRELAND
· Subject
to change.
SW I T Z E R L A N D
L I E C H T E N ST E I N
Phone: +41 55 415 90 90
info@stemmer-imaging.ch
THE NETHERLANDS
B E LG I U MCarl
. L U XZeiss
E M B OAG
U R G·
Phone: +31 575 495159
info@stemmer-imaging.nl
www.zeiss.com/lenses4industry