Takahashi backfocus distances
Model – F-ratio |
Focal length – metal back distance |
Reducer F-ratio – focal length – metal back distance |
Flattener F-ratio – focal length – metal back distance |
| FC-50 – f/8.0 | 400mm | f/5.8 – 290mm – 55.0mm | |
| 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 | |
| FC-65 – f/7.7 | 500mm | f/5.9 – 380mm – 60.79mm | |
| FCT-76 – f/6.4 | 487mm | f/4.5 – 345mm – 72.8mm | |
| FS-78 – f/8.1 | 630mm – 165.9mm | f/6.1 – 474mm – 72.3mm | |
| 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 | |
| FS-102 – f/8 | 820mm – 194.5mm | f/6.0 – 614mm – 83.9mm | |
| 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 | |
| FS-128 – f/8.1 | 1040mm – 198.78mm | f/6.0 – 770mm – 83.9mm | |
| 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 | |
| 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 | ||
| 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 Reducerf/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 Reducerf/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 Reducerf/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 | ||
| E-160 – f/3.3 | 530mm – 56.0mm | ||
| E-180ED – f/2.8 | 500mm – 56.0mm | ||
| E-200 f/4.0 | 620mm – 59.8mm | ||
| E-210 – f/3.0 | 628mm – 62.8mm | ||
| E-250 – f/3.4 | 854mm – 84.2mm | ||
| E-300 – f/3.8 | 1130mm – 122.0mm | ||
| E-350 – f/3.6 | 1248mm | ||
| 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
- Questi dati hanno solo lo scopo di fornire indicazioni sulla base di informazioni raccolte sul web. Astropixel.it declina ogni responsabilità. - These data are only intended to give indications based on information retrieved on the web. Astropixel.it declines all responsibility.
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