Not all data sheets are created equal!
Schneider's MTF graphs contain polychromatic diffraction MTF data - not just geometric MTF data. Schneider's MTF graphs are realistic indicators of actual lens performance in the field. If you are considering a lens from another supplier, it is in your best interests to ask exactly what their data sheets contain.
 

   
Extension
Tube (mm)
Magnification
Range
Working
Distance(mm)
Filter Thread
Max.
Image
Circle
Xenoplan
2.0/28mm
Compact
PDF

none
5
8
10
∞ - 5.9
5.9 - 2.9
3.7 - 2.3
2.9 - 2.0
∞ - 174
174 - 88.3
110 - 68.5
88.3 - 59.7
M30.5x0.5
22mm
Xenoplan
2.8/50mm
Compact
PDF
none
5
8
10
13 (8+5)
15 (10+5)
∞ - 10.0
10.0 - 5.0
6.3 - 3.9
5.0 - 3.3
3.9 - 2.8
3.3 - 2.5
∞ - 530
530 - 278
341 - 220
278 - 195
220 - 167
195 - 153
M30.5x0.5
22mm
Apo-Xenoplan
2.0/20mm
PDF

none
5
8
∞ - 7.2
5.0 - 2.8
2.8 - 2.0
∞ - 135
90 - 45
45 - 28
M35.5x0.75
24mm
Apo-Xenoplan
2.0/24mm
Compact
PDF
none
5
∞ - 3.7
3.7 - 2.2
∞ - 76
76 - 38
M37x0.75
24mm
Apo-Xenoplan
2.0/35mm
Compact
PDF

none
5
8
10
∞ - 5.3
9.0 - 2.5
5.1 - 2.0
3.9 - 2.8
∞ - 180
310 - 80
170 - 64
127 - 55
M37x0.75
24mm
 

Click PDF icon above to view datasheet
Explanation of nomenclature in datasheets.