Why no focal reducer

Does anyone know why canon or anyone else for that matter does not make focal reducer? Wouldn't you like to turn your 50 1.4 into a 35 f1.0 or close to it.

Lack of demand is probably the largest issue. I suspect that there are technical issues with making them work well on the wide angle lenses where such a tool would be desired.

Well, technically there are - they're called "close-up lenses" and they screw onto the front of your lens. The drawback is that they also take away infinity focus. There are a very few rear-mounting examples of this; one of which is the 1:1 adapter for the 50 mm f/2.5 macro (which focuses to 1:2 without the adapter; the adapter lets it focus to 1:1, and will also let other lenses focus closer than normal).

They seem to be popular among astronomers. Some do cause an amount of vignetting though.

The only focal length reducer that mounts on the rear of the lens I have ever heard of is one which only reduces the size of the image circle to a smaller format coverage, in order to both produce more angle of view.

http://www.engadget.co​m …edbooster-ef-nex-adapter/

"increasing the speed of a lens by a full stop. That may sound impossible, but it apparently works by concentrating the extra light-gathering area of a full-frame lens down to the smaller E-mount sensor area, turning an f4.0 lens into an f2.8 lens,"

This not only talks about the FL reducer, but in the first paragraph mentions what inherently has made that difficult up until now...

http://www.sansmirror.​com …reducer-lens-adapter.html

This is the direction canon needs to go in, they need to make a small sensor dslr in a small frame like the eos-m and make a focal reducer. then we can have below f1 lenses.

You can't make a focal reducer for EF lenses to work on an EOS camera. The way they work requires space for the focal reducer to fit in the optical path, which only works adapting to significantly shallower mounts. They can make one to use EF lenses on a NEX because the mount depth is about 26mm difference. You also require a larger imaging circle, so you'd have to use a FF lens on a APS-C body, or a medium format lens on a FF body, etc.

Rstanford wrote in post #16138966
This is the direction canon needs to go in, they need to make a small sensor dslr in a small frame like the eos-m and make a focal reducer. then we can have below f1 lenses.

But since you have to go to a smaller sensor for them to work, you take away effective aperture. All it does is get you back to where you would be if you used the lens on a FF camera in the first place.

Also, the attractiveness of a small camera like the EOS-M diminishes rapidly with adapters and larger FF lenses.

If thats not what I said thats what I meant, they need a smaller sensor in a small frame dslr camera.

Cameras are getting better and better at high ISO that I think lens manufacturer are going to stop trying to make them faster.

maverick75 wrote in post #16139002
Cameras are getting better and better at high ISO that I think lens manufacturer are going to stop trying to make them faster.

The relevance of big apertures is changing. The point used to be compensating for slow ISO. With that disappearing, the relevance will be DOF. If shallow DOF is not worth it for customers, they will stop buying them and manufacturers will stop making them. If shallow DOF is worth it, manufacturers will not stop. When I show someone a photo of them taken at 1.2, they get all excited and ask what camera I'm using. What they really want to know is how do I get a fast lens.

Tying back into topic: as tkbslc notes above, reducers seem to be creating equivalency with FF, not really gaining an advantage. You're shrinking the projected light as you're shrinking the sensor. 1.4 becomes 1.0 in brightness (concentrated light), but not shallow DOF. 1.4 on FF will look like 1.4 on crop + reducer, just with less of the ISO than would normally be needed.

Well all know aperture is not the only thing that controls DOF....

It also improves sharpness in the center.