Τρίτη, 20 Σεπτεμβρίου 2011

Takahashi back focus guide for CCD

  Takahashi Back Focus Guide for CCD and Photographic Applications

Model - Focal Ratio
Focal length - metal back distance
Reducer F-ratio · focal length · metal back distance
Flattener focal ratio · focal length · metal back distance
FC-50 . f/8.0
400mm
f/5.8 · 290mm · 55.0mm
n/a
FS-60C . f/5.9
355mm . 143.9mm
f/4.4 · 264mm · 56.0mm
f/6.2
FC-60E . f/8.3
500mm . 173.5mm
f/6.3 · 380mm · 60.7mm
n/a
FC-65 . f/7.7
500mm
f/5.9 · 380mm · 60.79mm
n/a
FCT-76 . f/6.4
487mm
f/4.5 · 345mm · 72.8mm
n/a
FS-78 . f/8.1
630mm . 165.9mm
f/6.1 · 474mm · 72.3mm
n/a
FSQ-85ED . f/5.3
450mm . 200mm
f/3.86 . 328mm . 72.2mm
f/8.0 . 675mm . 117.5mm
FCL90 (SKY-90) . f/5.6
500mm . 170.5mm
f/4.5 · 407mm · 72.2mm
same
FCT-100 . f/6.4
640mm
f/4.6 · 460mm · 76.95mm
n/a
FS-102 . f/8
820mm . 194.5mm
f/6.0 · 614mm · 83.9mm
n/a
FSQ-106 f/5
530mm · 120mm
 
 
FSQ-106ED f/5
530mm . 178mm
f/3.6 . 385mm . 72.2mm
f/8.0 . 850mm . 117.5mm
FC-125 . f/5.6
705mm
f/5.9 · 740mm · 134.5mm
n/a
FS-128 . f/8.1
1040mm . 198.78mm
f/6.0 · 770mm · 83.9mm
n/a
FS-128F . f/8.1
1040mm . 218.5mm
f/6.0 · 770mm · 106.2mm
f/8.2 · 1055mm · 106.2
FCT-150 . f/7.0
1050mm . 309mm
f/5.0· 750mm · 102.45mm
n/a
FS-152 . f/8
1216mm . 218.5mm
f/6.0 · 774mm · 106.2mm
f/8 · 1223mm · 106.2
BRC-250 f/5
1250mm · 106.2mm
n/a
n/a
FRC-300 f/7.8
2348mm · 106.2mm
f/5.9· 1770mm · 83.7mm
 
TOA-130 . f/7.7 2.7" focuser
1000.0mm · 200.0mm
f/5.79 · 780mm · 83.7mm w/TOA Reducer
f/5.6 . 728mm . 106.2mm w/Super Reducer 
f/7.5 . 980mm . 117.5mm w/TOA-130 FN
TOA-130 . f/7.7 4" focuser
1000.0mm · 200.0mm
f/5.79 · 780mm · 83.7mm w/TOA Reducer
f/5.6 . 728mm . 106.2mm w/Super Reducer
f/7.7 . 1000mm . 106.2mm w/TOA-130FF
TOA-150 . f/7.33
1100mm . 214mm
f/5.7 . 860mm . 106.2mm w/TOA Reducer
f/5.5 · 825mm · 106.2mm w/Super Reducer
f/7.3 . 1090mm . 106.2mm w/TOA-130FF
TSA-102S f/8.0
816mm
f/5.98 · 610mm w/TOA Reducer
f/7.84 . 800mm w/TOA Flattener
E-130 . f/3.3
430mm · 56.0mm
 n/a
 
E-160 . f/3.3
530mm · 56.0mm
 n/a
 
E-200 f/4.0
620mm · 59.8mm
  n/a
 
E-210 . f/3.0
628mm · 62.8mm
 n/a
 
E-250 . f/3.4
854mm · 84.2mm
  n/a
 
E-300 . f/3.8
1130mm · 122.0mm
   n/a
 
E-350 . f/3.6
1248mm
   n/a
 
M-180 . f/12.0
2160mm . 133.0mm
 
f/9.8· 1763mm · 56.0mm
M-210 . f/11.5
2415mm · 162.0mm
 
f/9.3 · 1961mm · 56.0mm
M-250 . f/12.0
3000mm · 150mm
 
f/9.3· 2328mm · 56.0mm
M-300 . f/11.9
3572mm · 107.5mm
 
f/9.1 . 2739mm . 56.0mm
CN-212 . f/12.4
2630mm · 154.0mm
f/9.9 · 2105mm . 56.0mm
 
CN-212 . f/3.9
820mm · 56.0mm
 
 
MT-130 . f/6.1
795mm . 91.0mm
f/4.8 · 618mm · 56.0mm
*f/8.2 · 1060mm · 61.0mm
MT-160 . f/6.3
1000.0mm . 93.0mm
f/4.9 · 776mm · 56.0mm
*f/8.3 · 1330mm · 61.0mm
MT-200 . f/6
1200.0mm . 87.0mm
f/4.9· 970mm · 56.0mm
*f/8.0 · 1600mm · 61.0mm
EXTENDER-Q 1.6X
125mm
 
 
EXTENDER-TOA 1.6X
117.5mm
 
 

*Extender/Flattener
The metal back distance is measured from the point at which the end of the reducer and the camera adapter come together, hence the name "metal back".
Takahashi has measured these distances for optimum performance for photographic or CCD applications.