It looks like Canon will be bringing one or more RF-S prime lenses for the Canon EOS R7 and Canon EOS R10. One of the most requested RF-S lenses is unsurprisingly a pancake lens. Keith at Northlight Images uncovered a patent at the USPTO with what looks to be RF-S pancake optical formulas.
None of these
Canon RF-S 14mm f/2.8
- Focal Length: 14.28mm
- F-Number: 2.90
- Half Angle of View: 51.88°
- Image Height: 18.20mm
- Total Lens Length: 57.50mm (image sensor to front element)
- Backfocus: 10.97mm
Canon RF-S 16mm f/2.8
- Focal Length: 16.48mm
- F-Number: 2.90
- Half Angle of View: 47.84°
- Image Height: 18.20mm
- Total Lens Length: 63.19mm (image sensor to front element)
- Backfocus: 12.54mm
Canon RF-S 10mm f/2.8
- Focal Length: 18.20mm
- F-Number: 2.90
- Half Angle of View: 45.00°
- Image Height: 18.20mm
- Total Lens Length: 63.45mm (image sensor to front element)
- Backfocus: 12.94mm
Canon RF-S 20mm f/2.8
- Focal Length: 20.10mm
- F-Number: 2.90
- Half Angle of View: 48.31°
- Image Height: 18.20mm
- Total Lens Length: 63.99mm (image sensor to front element)
- Backfocus: 11.16mm
Are the lens going to be inserted into mount pipe?
Maybe a misprint, but perhaps Canon has deliberately elected to have a larger than normal image circle with these wide-angle optics, in order to minimise vignetting and softness in the corners?
Or am I being daft?
But a larger image circle for IBIS makes sense.
The "specs" are, as you say, an informed guess - by a highly experienced commentator, Keith Cooper of Northlight.
I'd be extremely surprised if his guess was wrong.
If the larger image circle was purely to accommodate IBIS, I would have expected Canon to design *all* of its RF-S lenses to have this image circle, not just the pancakes under examination here.
I think it's more likely that the larger image circle has been chosen to minimise corner softness and vignetting, both of which are a bigger problem with wide-angle pancakes than with longer focal lengths.
But like Keith, I'm only guessing ;)
A pancake takes up next to no room, and can even be carried in a pocket, to be available at all times.
When going to an event where my primary lens was the 70-200/2.8, it was great to be able to drop the EF 40/2.8 into my pocket and swap on a normal focal length lens as needed (I typically carry with a BR strap attached to the lens foot, so the 70-200 could simply dangle from that as I shot with the 40 mm pancake) – it was a great, portable solution.
That’s not really an option with my R3, because having to carry both the adapter and the pancake lens defeats the purpose. I would definitely like a normal or wide (not ultrawide) pancake prime for RF full frame.
Slap that massive 50mm 1.2 on it if you want.