Canon EF 40mm f/2.8 Pancake Coming [CR3]

[Rocky]

The reality is that with the 'pancake lens" the size should be the same as other mirrorless with the lens mounted.

On a micro 4/3 camera, the flange distance is 20mm, so with a pancake lens you have 20mm + the depth of the pancake lens (20mm for the Panasonic 14mm pancake). Flange distance for most SLRs is over 40mm, so regardless of how thin the pancake is, you get a larger package.

It is not fair to use MICRO 4/3 as the size comparision. I am talking about APS-C or even FF in my suggestion

 

[funkboy]

So if the EF-s idea can work, then could an extension of this idea work? Retaining the EF / EF-s mount and flange distance, but with shorter back focus again lenses, ("EF-x?") so reducing the extension of the lens in front of the camera? Obviously this would probably mean a mirrorless body but crucially retain an APS-C sensor. Remove the pop up flash, or move it off centre, and you now have a smaller body.

Sounds like the kind of lens Pentax needs for their K-01...

The AF group (and likely also the IS group) would probably still need to be outside the camera body though; I think they'd have an awful hard time squeezing all those electronics into a barrel that fits through an EF mount opening & still maintain an APS-C image circle. Very different from Canon's existing lens designs, but then again they could probably pull it off given their lens design talent. Maybe if they went to a G1X-size image circle it would fit...

 

[maxxevv]

The reality is that with the 'pancake lens" the size should be the same as other mirrorless with the lens mounted.

On a micro 4/3 camera, the flange distance is 20mm, so with a pancake lens you have 20mm + the depth of the pancake lens (20mm for the Panasonic 14mm pancake). Flange distance for most SLRs is over 40mm, so regardless of how thin the pancake is, you get a larger package.

It is not fair to use MICRO 4/3 as the size comparision. I am talking about APS-C or even FF in my suggestion

The idea and physical laws are the same, regardless of sensor size.

If you extend the logic, it applies to the NEX system too. Why the NEX cameras can be so thin/slim ? Because of their lens flange distance. The rumoured mirrorless lenses from Canon have a shorter back focus plane distance than the Sony ones. From previous CR citations, supposedly only 1mm distance! So you can imagine how close the flange distances are.

Also, part of the reason with closer flange distances is that it allows the design and use of smaller optics for an equivalent focal plane area of focus.

 

[Rocky]

The reality is that with the 'pancake lens" the size should be the same as other mirrorless with the lens mounted.

On a micro 4/3 camera, the flange distance is 20mm, so with a pancake lens you have 20mm + the depth of the pancake lens (20mm for the Panasonic 14mm pancake). Flange distance for most SLRs is over 40mm, so regardless of how thin the pancake is, you get a larger package.

It is not fair to use MICRO 4/3 as the size comparision. I am talking about APS-C or even FF in my suggestion

The idea and physical laws are the same, regardless of sensor size.

RIGHT, Let us talk about phsical laws. A small sensor will only need a shorter focal length to give the same angle for a bigger sensor. Micro 3/4 has a mutiplicayion factor of 2. So the 14 mm Panasonic ancake lens will be equilvalent to a 28mm lens on a full frame. The 14mm will need a total of 40mm (20mm for the lense, 20mm for the fringe depth). That is a ration of 2.86. Now apply this ration for the 28mm for FF. than it will need 80mm. That is physical Law. Sensor size does not matter??? The bigger the sensor, the bigger the lense for the same viewing angle.

Thr Fringe diatance can be set to anything by the manufacturer to suit the usage. NEX fringe is set so thin for the using of adapter for the OLD range finder lenses,like Leica, Canon etc. The fringe distance can be set independent of the back focal plane distance. For mirrorless, the lenses have the luxury of going inside of the body and into the body. Have you look at the Leica wide angle lenses lately??? As the the rumores 1mm back focal distance lens from Canon, it is going to be huge. In order for it to work, the rear element of the lens MUST cover the whole sensor. What it mean is the lense will ge going inside of the fringe and way into the body. You just cannot make a cmera body with a 1mm fringe distance.

Here comes the phsical law again. the size of the optic is determined by the focal length, speed of the lens and the associated mechanical and electronics part. It got nothing to do wit hthe fringe distance (except for wide angle lens for range finder cameras, that is another story). Just look at the pancake lens from Panasonics. The optics are small, the lens dismeter is large. That is for the mechanical and theelectronis component. It has got nothing to do with the fringe distance.

 

[EOBeav]

So...what I hear you saying is, size matters?

RIGHT, Let us talk about phsical laws. A small sensor will only need a shorter focal length to give the same angle for a bigger sensor. Micro 3/4 has a mutiplicayion factor of 2. So the 14 mm Panasonic ancake lens will be equilvalent to a 28mm lens on a full frame. The 14mm will need a total of 40mm (20mm for the lense, 20mm for the fringe depth). That is a ration of 2.86. Now apply this ration for the 28mm for FF. than it will need 80mm. That is physical Law. Sensor size does not matter??? The bigger the sensor, the bigger the lense for the same viewing angle.

Thr Fringe diatance can be set to anything by the manufacturer to suit the usage. NEX fringe is set so thin for the using of adapter for the OLD range finder lenses,like Leica, Canon etc. The fringe distance can be set independent of the back focal plane distance. For mirrorless, the lenses have the luxury of going inside of the body and into the body. Have you look at the Leica wide angle lenses lately??? As the the rumores 1mm back focal distance lens from Canon, it is going to be huge. In order for it to work, the rear element of the lens MUST cover the whole sensor. What it mean is the lense will ge going inside of the fringe and way into the body. You just cannot make a cmera body with a 1mm fringe distance.

Here comes the phsical law again. the size of the optic is determined by the focal length, speed of the lens and the associated mechanical and electronics part. It got nothing to do wit hthe fringe distance (except for wide angle lens for range finder cameras, that is another story). Just look at the pancake lens from Panasonics. The optics are small, the lens dismeter is large. That is for the mechanical and theelectronis component. It has got nothing to do with the fringe distance.

 

[moreorless]

So would a "super EF-S" mount allowing for lenses with 1mm backfocus on a camera that can also mount EF/EF-s lenses actually be possible?

That does seem like an interesting way to apprach the concept of space saving, rather than making the body thinner you have 4cm of the lens optics inside instead.

Does strike me as a rather "canon like" move aswell since it would make EF/EF-s lenses easier to adapt and balance but not allow for older rangefinder lenses to be used.

 

[paul13walnut5]

I really think canon would be wrong to break the 25ish year legacy that EF lenses have. Anything they make from now on should be friendly towards EF. EF is their K, Their F. Their mirrorless should on some level be compatable with EF. How many folk buy Pentax Q's or Nikon 1s, that would be better buying a system that supports legacy and micro lenses.

It's unfortunate to say, but Sony were the most forward looking in this regard. But then again, how many minolta dynax lagacy users have an NEX?

 

[Rocky]

I really think canon would be wrong to break the 25ish year legacy that EF lenses have. Anything they make from now on should be friendly towards EF. EF is their K, Their F. Their mirrorless should on some level be compatable with EF. How many folk buy Pentax Q's or Nikon 1s, that would be better buying a system that supports legacy and micro lenses.

It's unfortunate to say, but Sony were the most forward looking in this regard. But then again, how many minolta dynax lagacy users have an NEX?

Canon should also be friendly to the EF-S also, if the mirrorless is APS-C sensor. I agree that the NEX is forward thinking about letting the owner to be able to use OLD range finder lenses. But in reality, how many people are doing that ?? When a range finder lens is used in NEX or any mirrorless, manual focusing is required. So we need to wide open the lens to get the focusing accuracy from the "lifeview", then stop down the lens to take picture. By that time the screen will be way too dim to be used. Also it is a slow process. The otherway is to use "zone focusing" to avoid wide open and stop down the lens. But we still have to deal with the dim screen.

 

[Daniel Flather]

The more I think of this lens the more I want one, but it has to be tiny. This lens on my 5D3 would be my mirrorless mirrored camera.

 

[maxxevv]

RIGHT, Let us talk about phsical laws. A small sensor will only need a shorter focal length to give the same angle for a bigger sensor. Micro 3/4 has a mutiplicayion factor of 2. So the 14 mm Panasonic ancake lens will be equilvalent to a 28mm lens on a full frame. The 14mm will need a total of 40mm (20mm for the lense, 20mm for the fringe depth). That is a ration of 2.86. Now apply this ration for the 28mm for FF. than it will need 80mm. That is physical Law. Sensor size does not matter??? The bigger the sensor, the bigger the lense for the same viewing angle.

Thr Fringe diatance can be set to anything by the manufacturer to suit the usage. NEX fringe is set so thin for the using of adapter for the OLD range finder lenses,like Leica, Canon etc. The fringe distance can be set independent of the back focal plane distance. For mirrorless, the lenses have the luxury of going inside of the body and into the body. Have you look at the Leica wide angle lenses lately??? As the the rumores 1mm back focal distance lens from Canon, it is going to be huge. In order for it to work, the rear element of the lens MUST cover the whole sensor. What it mean is the lense will ge going inside of the fringe and way into the body. You just cannot make a cmera body with a 1mm fringe distance.

Here comes the phsical law again. the size of the optic is determined by the focal length, speed of the lens and the associated mechanical and electronics part. It got nothing to do wit hthe fringe distance (except for wide angle lens for range finder cameras, that is another story). Just look at the pancake lens from Panasonics. The optics are small, the lens dismeter is large. That is for the mechanical and theelectronis component. It has got nothing to do with the fringe distance.

You've got your physics a little mixed up and the topic/areas being discussed here too it seems.

When we talk about back focus plane distances and how it affects the size of the lens, we are referring to sensors of the same and equal size, not across different sizes. When you get one design with a back focus plane at 1mm versus one at 30mm, the optics required for the shorter one is smaller. Par equal area of focus and within limits of optics diffraction. Which is why Leica comes into such a picture. It was design to use FF (in the film days) but yet for equivalent focal length and aperture lens, they were smaller than say Canon or Nikon designs, even if they were all full manual, non-AF lenses.

In this case of Canon's mirrorless, nobody seems to be certain for sure what's the sensor size. And we can only infer from the back focus plane distance that for the sensor size they are designing for, they are trying very hard to miniaturize the size of the lenses. And for what ever size sensor they are using. Be it a FF, 1.3x, 1.6x or 1.85x crop, it SHOULD be (within limitations of cost and practicality) smaller than lenses designed for sensors of equivalent crop factor.

 

[Rocky]

RIGHT, Let us talk about phsical laws. A small sensor will only need a shorter focal length to give the same angle for a bigger sensor. Micro 3/4 has a mutiplicayion factor of 2. So the 14 mm Panasonic ancake lens will be equilvalent to a 28mm lens on a full frame. The 14mm will need a total of 40mm (20mm for the lense, 20mm for the fringe depth). That is a ration of 2.86. Now apply this ration for the 28mm for FF. than it will need 80mm. That is physical Law. Sensor size does not matter??? The bigger the sensor, the bigger the lense for the same viewing angle.

Thr Fringe diatance can be set to anything by the manufacturer to suit the usage. NEX fringe is set so thin for the using of adapter for the OLD range finder lenses,like Leica, Canon etc. The fringe distance can be set independent of the back focal plane distance. For mirrorless, the lenses have the luxury of going inside of the body and into the body. Have you look at the Leica wide angle lenses lately??? As the the rumores 1mm back focal distance lens from Canon, it is going to be huge. In order for it to work, the rear element of the lens MUST cover the whole sensor. What it mean is the lense will ge going inside of the fringe and way into the body. You just cannot make a cmera body with a 1mm fringe distance.

Here comes the phsical law again. the size of the optic is determined by the focal length, speed of the lens and the associated mechanical and electronics part. It got nothing to do wit hthe fringe distance (except for wide angle lens for range finder cameras, that is another story). Just look at the pancake lens from Panasonics. The optics are small, the lens dismeter is large. That is for the mechanical and theelectronis component. It has got nothing to do with the fringe distance.

You've got your physics a little mixed up and the topic/areas being discussed here too it seems.

When we talk about back focus plane distances and how it affects the size of the lens, we are referring to sensors of the same and equal size, not across different sizes. When you get one design with a back focus plane at 1mm versus one at 30mm, the optics required for the shorter one is smaller. Par equal area of focus and within limits of optics diffraction. Which is why Leica comes into such a picture. It was design to use FF (in the film days) but yet for equivalent focal length and aperture lens, they were smaller than say Canon or Nikon designs, even if they were all full manual, non-AF lenses.

In this case of Canon's mirrorless, nobody seems to be certain for sure what's the sensor size. And we can only infer from the back focus plane distance that for the sensor size they are designing for, they are trying very hard to miniaturize the size of the lenses. And for what ever size sensor they are using. Be it a FF, 1.3x, 1.6x or 1.85x crop, it SHOULD be (within limitations of cost and practicality) smaller than lenses designed for sensors of equivalent crop factor.

You are the one that mixed up the sensor size. I started out with the Canon 40mm pancake lens which is supposed to be for the FF. You switched the discussion to micro 4/3 and use it to justify a smaller lens.
My physics is right. The reason why some Leica lenses are smaller than DSLR lenses is that the 35mm lens for Leica does not need the retro-telephoto design that is manditory for DLSR. When you look at the 21 mm Leica lens (it is a retro-telephoto design). It is not small at all. This proves that the fringe distance does not decrease the size of the lens. Even the 50mm Summicron, it is longer than the 50mm Canon DSLR lens. The longer Leica lense is just as big as the DSLR lenses. FYI, f stop is define as the focal length/diameter of the aperture. This will limit the minimum total size of the lens for a given focal length, regardless of the fringe. I suggest you look at the Leica lenses physically before any further discussion. just as I said before if there is a 1mm back focus plane lens exist, the rear element must cover the ENTIRE sensor to make it work. Therefore this lens cannot be small. Did you take a class in optics???

 

[Positron]

RIGHT, Let us talk about phsical laws. A small sensor will only need a shorter focal length to give the same angle for a bigger sensor. Micro 3/4 has a mutiplicayion factor of 2. So the 14 mm Panasonic ancake lens will be equilvalent to a 28mm lens on a full frame. The 14mm will need a total of 40mm (20mm for the lense, 20mm for the fringe depth). That is a ration of 2.86. Now apply this ration for the 28mm for FF. than it will need 80mm. That is physical Law. Sensor size does not matter??? The bigger the sensor, the bigger the lense for the same viewing angle.

Thr Fringe diatance can be set to anything by the manufacturer to suit the usage. NEX fringe is set so thin for the using of adapter for the OLD range finder lenses,like Leica, Canon etc. The fringe distance can be set independent of the back focal plane distance. For mirrorless, the lenses have the luxury of going inside of the body and into the body. Have you look at the Leica wide angle lenses lately??? As the the rumores 1mm back focal distance lens from Canon, it is going to be huge. In order for it to work, the rear element of the lens MUST cover the whole sensor. What it mean is the lense will ge going inside of the fringe and way into the body. You just cannot make a cmera body with a 1mm fringe distance.

Here comes the phsical law again. the size of the optic is determined by the focal length, speed of the lens and the associated mechanical and electronics part. It got nothing to do wit hthe fringe distance (except for wide angle lens for range finder cameras, that is another story). Just look at the pancake lens from Panasonics. The optics are small, the lens dismeter is large. That is for the mechanical and theelectronis component. It has got nothing to do with the fringe distance.

You've got your physics a little mixed up and the topic/areas being discussed here too it seems.

When we talk about back focus plane distances and how it affects the size of the lens, we are referring to sensors of the same and equal size, not across different sizes. When you get one design with a back focus plane at 1mm versus one at 30mm, the optics required for the shorter one is smaller. Par equal area of focus and within limits of optics diffraction. Which is why Leica comes into such a picture. It was design to use FF (in the film days) but yet for equivalent focal length and aperture lens, they were smaller than say Canon or Nikon designs, even if they were all full manual, non-AF lenses.

In this case of Canon's mirrorless, nobody seems to be certain for sure what's the sensor size. And we can only infer from the back focus plane distance that for the sensor size they are designing for, they are trying very hard to miniaturize the size of the lenses. And for what ever size sensor they are using. Be it a FF, 1.3x, 1.6x or 1.85x crop, it SHOULD be (within limitations of cost and practicality) smaller than lenses designed for sensors of equivalent crop factor.

You are the one that mixed up the sensor size. I started out with the Canon 40mm pancake lens which is supposed to be for the FF. You switched the discussion to micro 4/3 and use it to justify a smaller lens.
My physics is right. The reason why some Leica lenses are smaller than DSLR lenses is that the 35mm lens for Leica does not need the retro-telephoto design that is manditory for DLSR. When you look at the 21 mm Leica lens (it is a retro-telephoto design). It is not small at all. This proves that the fringe distance does not decrease the size of the lens. Even the 50mm Summicron, it is longer than the 50mm Canon DSLR lens. The longer Leica lense is just as big as the DSLR lenses. FYI, f stop is define as the focal length/diameter of the aperture. This will limit the minimum total size of the lens for a given focal length, regardless of the fringe. I suggest you look at the Leica lenses physically before any further discussion. just as I said before if there is a 1mm back focus plane lens exist, the rear element must cover the ENTIRE sensor to make it work. Therefore this lens cannot be small. Did you take a class in optics???

Well you could do it, but the challenges in keeping the aberrations in check would be daunting, to say the least.

On the other hand, if the sensor itself were sufficiently curved, you could get as close to it with a normal rear element as you please. A combination of the two approaches could be reasonable, while significantly slimming the total package.

Seriously though if anyone has it right it's Intel. They don't break what's working, they just slim it down a little more on every other iteration, using the ones in between to improve the current process. It works because no single step is too ambitious, so they always make forward progress and never have complete flops. Keep doing that for a few years and you can have some seriously killer products.

 

[noncho]

Well, it's not bad idea for lens like this, but for me it's to close to my 60 2.8 macro.
I would go for unexpensive EF-s 30 1.8 and 12 2.8, but from the prices of new 24 and 28 IS it seems that Canon don't want to give us good normal price lens.