Can you avoid light loss when adapting Canon FD lenses to Canon EOS bodies?
Asked 7/21/2017
7 views
2 answers
0
I’m using older Canon FD lenses on a Canon EOS camera and I’ve noticed a loss of light when using an FD-to-EOS adapter. Is there any way to keep infinity focus without losing stops, or is that unavoidable with this type of adapter? Are there better camera mounts for using FD lenses without the light-loss penalty?
Originally by Photography Stack Exchange contributor. Source · Licensed CC BY-SA 4.0
Photography Stack Exchange contributor
9y ago
2 Answers
2
The FD to EOS adapter needs a lens to correct for the difference in flange distance, and make the lens focus correctly at infinity. The optical design and the inherent light loss cannot be avoided. If you have a significant investment in such lenses (or an emotional attachment to them), maybe the best way to deal with the light loss is to get a camera that allows you to use a high ISO (most recent cameras allow you to work at very high sensitivity with very little noise).
An alternative is use those lenses on non canon cameras with a short flange distance. That would allow you to use a glass-less adapter. Sony cameras with E mount would be well suited for this.
Originally by user39557. Source · Licensed CC BY-SA 4.0
user39557
9y ago
0
Generated from our catalog & community — verify before relying on it.
No—if you want infinity focus on a Canon EOS DSLR with Canon FD lenses, the light loss from the corrective adapter is essentially unavoidable.
FD lenses were designed for a shorter flange distance than EOS. On an EOS body, the adapter has to include optical elements to restore infinity focus. That makes it behave like a small teleconverter: focal length increases, but the physical aperture does not, so the effective maximum aperture gets slower.
So on EOS DSLRs, you generally cannot avoid this penalty if you need infinity focus.
A reported two-stop loss sounds higher than typical; many such adapters act more like about a 1.4x teleconverter, which is closer to a one-stop loss. But some loss and some image-quality compromise are inherent to the design.
If you want to use FD lenses closer to their original behavior, the better option is a camera with a shorter flange distance, such as a mirrorless mount. On those systems, FD lenses can usually be adapted with a simple glassless adapter, avoiding the teleconverter-like light loss.
Recommended products
UniqueBot
AI9y ago
Your Answer
Related Questions
Is there a comprehensive list of lens mount adapters by camera and lens mount?
Which vintage manual-focus lenses can adapt to a Canon EOS 550D with infinity focus?
Why won't a Canon FD 28mm lens focus properly on an EOS Rebel T6/1300D?
Can I use cheap manual M42 or FD lenses on a Nikon D7000 instead of Nikon F-mount manual lenses?
Can Canon AE-1 FD lenses be used on a Canon EOS 60D with an adapter?