Patent: Some very strange full frame lenses

Pape

EOS RP
Dec 31, 2018
594
362
I was mostly joking, but I meant the inner barrel would retract mostly to protect it when unattached. Although I guess it could be fixed and come with a new type of rear lens cap. I presume there are some optical, rather than size, advantages to having a ridiculously short backfocus distance in these designs.
Arent optical advantages also size advantages. Less needed correction lenses ,smaller stuff?
 

Daner

AE-1 Program
I'd pretend I would be a little mad as someone who just picked up the R5 and 35mm 1.8 as my everyday compact carry camera, but if Canon released a fixed lens full frame compact 35mm 1.4 camera I would probably still end up with one anyway for the fun of it :ROFLMAO:
LP-E6NH battery, single SD card slot, same sensor, AF system, IBIS, and viewfinder as the R5. I could live with reduced video capabilities and a fixed screen rather than tilty/flippy, but weather sealing would be appreciated.
 

SwissFrank

from EOS 1N to R
Dec 9, 2018
428
185
Setting aside the 0.00mm model, these could theoretically be mounted on the R. I suppose some current RF lenses already extend quite a ways into the camera. I had the Contax G2 in the 90s, and its 16/8 lens was almost entirely inside the camera. In the early 70s I think all the big companies had 21mm lenses for their SLRs that required you lock up the mirror before shooting, because they extended into the camera. (21mm being just over 90 degrees and good for capturing an entire room in a photo.)
 

canonnews

EOS RP
CR Pro
Dec 27, 2017
754
1,205
Canada
www.canonnews.com
Setting aside the 0.00mm model, these could theoretically be mounted on the R. I suppose some current RF lenses already extend quite a ways into the camera. I had the Contax G2 in the 90s, and its 16/8 lens was almost entirely inside the camera. In the early 70s I think all the big companies had 21mm lenses for their SLRs that required you lock up the mirror before shooting, because they extended into the camera. (21mm being just over 90 degrees and good for capturing an entire room in a photo.)
not really. There is the shutter assembly in front of the sensor on an R.

on a SLR a lens ingress would hit the mirror long before it would hit the shutter.
 

canonnews

EOS RP
CR Pro
Dec 27, 2017
754
1,205
Canada
www.canonnews.com
some sort of industrial QC camera or satellite camera? Or hi res security cam?
curious note is that they usually state something like this or automotive applications. but it's decidedly full frame, which is odd, and as far as "purposes of illustration of use" they show a camera. So I don't know. I do know they are completeyl bizzare designs that i've never seen the like before.
 
  • Like
Reactions: Berowne

Berowne

... they sparkle still the right Promethean fire.
Jun 7, 2014
292
138
curious note is that they usually state something like this or automotive applications. but it's decidedly full frame, which is odd, and as far as "purposes of illustration of use" they show a camera. So I don't know. I do know they are completeyl bizzare designs that i've never seen the like before.
Thanks for your information about theses lenses.

In 1966 Zeiss introduced a lens called Hologon in two versions a 15mm f8 and a 16mm f8. The 15mm/f8 lens was designed as fixed lens for an analog "full format" camera (there also existed large format versions as prototypes for the Linhof Technica). The back focal length of the 15mm lens was 4,5mm.
From the series of articles on lens names: Distagon, Biogon and Hologon (pg. 13)

Greetings from Frankfurt am Main - Andy
 

Eclipsed

EOS R5, "Hefty Fifty" and more.
Apr 30, 2020
143
144
I think I know where Canon is heading with this. The electronic shutter has several issues, especially sports or panning. Canon may be on the way to a totally new method of reading the sensor. Currently, the sensor is read while it is still gathering photons. My thought is Canon might be designing a sensor where all the sensor's photodiodes are turned off at the desired shutter speed, then read. If this is where they are heading, there will be no need for the mechanical shutter, it will allow lens designs with minimal rear element to sensor distance. The closer the rear element is to the sensor, aberrations like Chromatic, Coma, and Spherical will be greatly reduced. If a lens has a minute amount of aberrations at the exit of the last element, the distance to the sensor is the key. Kind of like light going through a prism- the further away the prism is from the viewing surface, the wider the rainbow.(more noticeable Chromatic aberration) The final result is higher resolution and better contrast.
Almost as if the sensor were immersed within the rear element
 
  • Like
Reactions: KeithBreazeal
Jan 16, 2014
1,310
236
www.kbvp.com
Off on another tangent...
If the rear element was as close to the imaging sensor as possible, the lens's IS corrections for camera shake would be more effective due to shorter distance traveled from the IS elements to the image plane. Depending on the focal length of the lens and where the IS lens group distance from the focal plane, the len's IS could be more effective by a great percentage. By having the rear element deep inside the body, it may be possible to have the IS as far back as the lens mount. This would(depending on the lens) give a few more stops of effective stabilization. Coupled with IBIS, that would be huge advantage for hand held photo and video shooters.
 

Antono Refa

EOS R
Mar 26, 2014
1,075
259
Off on another tangent...
If the rear element was as close to the imaging sensor as possible, the lens's IS corrections for camera shake would be more effective due to shorter distance traveled from the IS elements to the image plane. Depending on the focal length of the lens and where the IS lens group distance from the focal plane, the len's IS could be more effective by a great percentage. By having the rear element deep inside the body, it may be possible to have the IS as far back as the lens mount. This would(depending on the lens) give a few more stops of effective stabilization. Coupled with IBIS, that would be huge advantage for hand held photo and video shooters.
Can IBIS be used with such short back focus?

If the distance is zero, the sensor touches the back element, and can't move at all.

With the limitations of electronics and mount (back element can't be bigger than the throat diameter of 54mm, and light hitting at an oblique angle not reaching the photosites), I'm not sure effective IBIS can be designed if the lens is .5mm from the sensor.
 

Dragon

EF 800L
May 29, 2019
260
214
Interesting that the 35 is much longer overall than the 50s even though it has 0 BF distance. These could be for low light security cameras. Properly placed, one 8k FF camera could cover a lot of real estate.
 

SwissFrank

from EOS 1N to R
Dec 9, 2018
428
185
on a SLR a lens ingress would hit the mirror long before it would hit the shutter.
To be clear I'm talking about some old SLR lenses that required you to lock up the mirror before use. They came with an external viewfinder you put on the hotshoe. IIRC all the main brands made such a 21mm maybe late 60s/early 70s.
 

canonnews

EOS RP
CR Pro
Dec 27, 2017
754
1,205
Canada
www.canonnews.com
To be clear I'm talking about some old SLR lenses that required you to lock up the mirror before use. They came with an external viewfinder you put on the hotshoe. IIRC all the main brands made such a 21mm maybe late 60s/early 70s.
yes, but SLRs had a backfocus distance of over 40mm.

the R has a backfocus distance of 20mm, you can't get to 0mm to 3.5mm because there's a shutter in front of the sensor.

you can get 10-20mm back on an SLR lens without hitting the shutter because you are still ~20mm away from the film plane / sensor, you have to mirror lockup, but that's something different.
 

hne

Gear limits your creativity
Jan 8, 2016
313
34
yes, but SLRs had a backfocus distance of over 40mm.

the R has a backfocus distance of 20mm, you can't get to 0mm to 3.5mm because there's a shutter in front of the sensor.

you can get 10-20mm back on an SLR lens without hitting the shutter because you are still ~20mm away from the film plane / sensor, you have to mirror lockup, but that's something different.
You could, and it's not too different. You'd have to lock up the shutter and use electronic shutter only.
 
  • Like
Reactions: SwissFrank

SwissFrank

from EOS 1N to R
Dec 9, 2018
428
185
Interesting that the 35 is much longer overall than the 50s even though it has 0 BF distance. These could be for low light security cameras. Properly placed, one 8k FF camera could cover a lot of real estate.
a problem is you don't want the security camera to be so valuable that people just come in to steal the camera