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Nikon makes fresnel telephoto lenses, and they save size + weight vs their classic counterparts

Theodores 7y ago
In practice though most lenses and applications move away from being Fresnel. The lights get better or a camera or other screen technology replaces it. Fresnel lenses are like motorbike sidecars, they are a cheap hack. But if I was to post 'you don't see motorbike sidecars these days' then some nitpicker on HN would Google search a new Kickstarter project of a motorbike sidecar and - two seconds later - mod me down for being generally but not universally correct. As I understand it the Nikon lenses are not 'Fresnel' as we know it. The idea is to combine a regular lens with a Fresnel lens to remove chromatic aberration. The weight saving isn't what it is about since there is still a regular lens that the Fresnel lens works with.
- i_am_proteus 7y ago
  > In practice though most lenses and applications move away from being Fresnel. Tungsten fresnel lights (and now LED fresnel lights) are very common in videography. The lens provides a simple spot/flood mechanism.
- rangibaby 7y ago
  The fresnel element version of the 300mm f/4 lens reduces the weight by half and the size by one third compares to the non-fresnel version
- hug 7y ago
  > But if I was to post 'you don't see motorbike sidecars these days' then some nitpicker on HN would Google search a new Kickstarter project of a motorbike sidecar and - two seconds later - mod me down for being generally but not universally correct. I'm of course not going to downvote you, but just to help you out with your point IMZ-Ural still manufacture motorcycles with sidecars to this day, and in fact are working on a fully electric model.
maxxxxx 7y ago
True! "Proprietary Phase Fresnel technology" on the 500 PF. It looks very different though.
ISL 7y ago
Canon makes them too -- look for the DO lenses.
- buserror 7y ago
  For many years now I've owned a 70-300 DO very very compact zoom lens and always been happy with it. There are some rare optical artifacts, in some lights, on some subjects, but it's never been a problem in real life.

In practice though most lenses and applications move away from being Fresnel. The lights get better or a camera or other screen technology replaces it. Fresnel lenses are like motorbike sidecars, they are a cheap hack. But if I was to post 'you don't see motorbike sidecars these days' then some nitpicker on HN would Google search a new Kickstarter project of a motorbike sidecar and - two seconds later - mod me down for being generally but not universally correct. As I understand it the Nikon lenses are not 'Fresnel' as we know it. The idea is to combine a regular lens with a Fresnel lens to remove chromatic aberration. The weight saving isn't what it is about since there is still a regular lens that the Fresnel lens works with.

i_am_proteus 7y ago
> In practice though most lenses and applications move away from being Fresnel. Tungsten fresnel lights (and now LED fresnel lights) are very common in videography. The lens provides a simple spot/flood mechanism.
rangibaby 7y ago
The fresnel element version of the 300mm f/4 lens reduces the weight by half and the size by one third compares to the non-fresnel version
hug 7y ago
> But if I was to post 'you don't see motorbike sidecars these days' then some nitpicker on HN would Google search a new Kickstarter project of a motorbike sidecar and - two seconds later - mod me down for being generally but not universally correct. I'm of course not going to downvote you, but just to help you out with your point IMZ-Ural still manufacture motorcycles with sidecars to this day, and in fact are working on a fully electric model.

maxxxxx 7y ago

True! "Proprietary Phase Fresnel technology" on the 500 PF. It looks very different though.

ISL 7y ago

Canon makes them too -- look for the DO lenses.

buserror 7y ago
For many years now I've owned a 70-300 DO very very compact zoom lens and always been happy with it. There are some rare optical artifacts, in some lights, on some subjects, but it's never been a problem in real life.