Piecing together a photo and a patent, it seems that Canon might be releasing an RF macro lens, 100mm, with adjustable floating group for SA adjustment.
https://www.canonnews.com/canon-patent- ... -with-114x
It seems that L3 or L4 is the floating group.
Interesting Canon 100mm - 1.4x Possibilty
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Re: Interesting Canon 100mm - 1.4x Possibilty
Interesting. This is not the same thing as magnification close range correction, this is more of the smooth bokeh apodization type effect I wonder?
Minolta made a lens with this kind of effect in the 80s.
Best,
Robert
Minolta made a lens with this kind of effect in the 80s.
Best,
Robert
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Re: Interesting Canon 100mm - 1.4x Possibilty
Sony is still making lenses descended from this lineage, with their STF (Smooth Trans Focus) lenses.RobertOToole wrote: ↑Thu Apr 08, 2021 11:47 amInteresting. This is not the same thing as magnification close range correction, this is more of the smooth bokeh apodization type effect I wonder?
Minolta made a lens with this kind of effect in the 80s.
Best,
Robert
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Re: Interesting Canon 100mm - 1.4x Possibilty
Ah, yes, STF, forgot the acronym and the fact they are still making them! Thanks for the help.Doppler9000 wrote: ↑Thu Apr 08, 2021 12:09 pmSony is still making lenses descended from this lineage, with their STF (Smooth Trans Focus) lenses.RobertOToole wrote: ↑Thu Apr 08, 2021 11:47 amInteresting. This is not the same thing as magnification close range correction, this is more of the smooth bokeh apodization type effect I wonder?
Minolta made a lens with this kind of effect in the 80s.
Best,
Robert
Best,
Robert
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Re: Interesting Canon 100mm - 1.4x Possibilty
Likely an apd element, it's also deployed in modern phase contrast objectives, where the internal phase annulus is apodised. Similar theory but different application and outcome.
Pros is nice and smooth blur orbs, cons is a huge hit in T_no, and $$$$.
Laowa makes one too, off the charts sharpness, the model will not like to see her skin zoomed in at 100% with that lens... (personal experience).
Pros is nice and smooth blur orbs, cons is a huge hit in T_no, and $$$$.
Laowa makes one too, off the charts sharpness, the model will not like to see her skin zoomed in at 100% with that lens... (personal experience).
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Re: Interesting Canon 100mm - 1.4x Possibilty
FYI, the ring is used to "control defocus" or rather it's a spherical aberration compensation ring, known as a CC (correction collar) on objectives.
Not sure how it would pan out on such a low magnification lens but objective technology being used on consumer optics is probably a good thing, just not for the wallet.
Not sure how it would pan out on such a low magnification lens but objective technology being used on consumer optics is probably a good thing, just not for the wallet.
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Re: Interesting Canon 100mm - 1.4x Possibilty
Canon has just announced that it really is a spherical aberration control ring. https://www.canon.co.uk/lenses/canon-rf ... ro-is-usm/
The announcement is about the bokeh control. What I'm particularly curious about is whether the over-correction range is enough to image through thick glass or a layer of water, which would be great for aquatic insects.
The announcement is about the bokeh control. What I'm particularly curious about is whether the over-correction range is enough to image through thick glass or a layer of water, which would be great for aquatic insects.
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Re: Interesting Canon 100mm - 1.4x Possibilty
Maybe a dumb question, but if used as a tube lens would that correction ring still work? I know Infinity sells a tube lens that corrects for spherical aberrations, though like many of their products it is hard to tell how good it actually is.
Re: Interesting Canon 100mm - 1.4x Possibilty
I am also very interested. SA can be corrected by changing tube length for finite objectives.Scarodactyl wrote: ↑Wed Apr 14, 2021 8:45 amMaybe a dumb question, but if used as a tube lens would that correction ring still work? I know Infinity sells a tube lens that corrects for spherical aberrations, though like many of their products it is hard to tell how good it actually is.
If this lens is used as a TL for an infinite objective when shoouting through glass of improper thickness, is there any chance that this lens will be able to correct the SA?
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Re: Interesting Canon 100mm - 1.4x Possibilty
Look up US Patent 7,869,139.
I am guessing it can be used this way but it would be better for someone to try it out first.
I am guessing it can be used this way but it would be better for someone to try it out first.