Why no cheap f/1.0 fixed lenses?

I was thinking about lens design / manufacture. Surely it'd be "easy" (relatively speaking) to make a lens that has an f/1.0 aperture but a fixed focus? Lo an behold, I found one!

http://cgi.ebay.co.uk …3A1%7C39%3A1%7C​240%3A1318


So why don't they make similar lenses now? I admit the pictures from that lens seem poor, but why can't say canon make a 50mm f/1.0 with a fixed focal distance of say 2m? It'd be indestructible, super-fast AND cheap!

I don't know what I'd use it for...

Simple, not enough people would buy them. The 50mm lenses are the easiest to make, but they are also cheaper than similar lenses because they sell so many of them. They could made a fixed focus for cheap, but not enough of a price difference to get people to buy it and make it worth building.

I expect lenses like this are built for a specific purpose, like in a laboratory.

Additionally, most cameras today shoot decent pictures at ISO 800 or above. There is less pressure for larger apertures, except for artistic DOF stuff. A lot of that can be done with a tilt/shift.

You will rarely see speciality stuff (macro, tilt/shift, super telephoto, super aperture) for cheap because they can't sell many.

They could make a telephoto one which has handhold speeds in any light for birding / sports...

laydros wrote in post #7802010
Simple, not enough people would buy them. The 50mm lenses are the easiest to make, but they are also cheaper than similar lenses because they sell so many of them. They could made a fixed focus for cheap, but not enough of a price difference to get people to buy it and make it worth building.

I expect lenses like this are built for a specific purpose, like in a laboratory.

Additionally, most cameras today shoot decent pictures at ISO 800 or above. There is less pressure for larger apertures, except for artistic DOF stuff. A lot of that can be done with a tilt/shift.

You will rarely see speciality stuff (macro, tilt/shift, super telephoto, super aperture) for cheap because they can't sell many.

That's a good point - I haven't experienced and camera with a great performance above ISO800. I'm looking forward to a 5dII upgrade!

motoroller wrote in post #7802018
They could make a telephoto one which has handhold speeds in any light for birding / sports...

But for birding or sports, a fixed focus would be of very little use.

You see the sharpness? I'd rather have f/1.2, f/1.4, or f/1.8 and actually get a sharp photo.

I can't imagine a more useless lens than a fixed f/1 lens that you can't focus. How often do you shoot things that

a) are stationary so you have time to move yourself to focus the lens.
b) will be framed perfectly at that one single focal point
c) require extremely shallow DOF OR have very little light in which to shoot.

If you find yourself often in situations where a, b, and c all apply, then it might be useful, but I can tell you that might coincide for me about once every two years, which is pretty useless. I'd rather give up some of that extreme DOF and spend a bit more money, and go for, say, a Nikkor 50 f/1.2 AIS or Rokkor 58 f/1.2 converted to EOS for my cheap f/1.2 needs....I think that would do fine. Heck, on full frame, I find f/1.4 almost always too shallow for any close up work, so I don't need f/1.0, especially in an inflexible lens.

ChrisRabior wrote in post #7802036
You see the sharpness? I'd rather have f/1.2, f/1.4, or f/1.8 and actually get a sharp photo.

Good point, the DOF of f/1.0 or even 1.2 is tough to control. Like I said, limited use = limited sales.

There's no need for a cheap lens to be fixed focus. A simple helicoid mechanism is all that's required to move the whole assembly in or out to focus. The problem is that you're stuck with a very poor image. Would Canon want to put their name to such a thing? Correcting all the aberrations you get at those extreme apertures is fiendishly difficult and expensive. Just look at the EF50mm f/1.0L, and it still wasn't as good at all overlapping apertures as the EF50mm f/1.4, at a tiny fraction of the price.

Canon did make a 50mm f0.95 lens and was sold late 50s and early 60s

People grumble that they have to carry several primes with them for different focus lengths. Now you suggest to multiply that by carryiing lenses for all possible focus distances ?

The DOF of 1.8 is so thin...the DOF of 1.2 is literally a razer. 0.95 would be a piece of nylon thread kind of DOF

Jman13 wrote in post #7802072
I can't imagine a more useless lens than a fixed f/1 lens that you can't focus. How often do you shoot things that

a) are stationary so you have time to move yourself to focus the lens.
b) will be framed perfectly at that one single focal point
c) require extremely shallow DOF OR have very little light in which to shoot.

If you find yourself often in situations where a, b, and c all apply, then it might be useful, but I can tell you that might coincide for me about once every two years, which is pretty useless. I'd rather give up some of that extreme DOF and spend a bit more money, and go for, say, a Nikkor 50 f/1.2 AIS or Rokkor 58 f/1.2 converted to EOS for my cheap f/1.2 needs....I think that would do fine. Heck, on full frame, I find f/1.4 almost always too shallow for any close up work, so I don't need f/1.0, especially in an inflexible lens.

+1 +1 +1 +1 +1 +1 +1 +1 +1

khall wrote in post #7802961
Canon did make a 50mm f0.95 lens and was sold late 50s and early 60s

Yeah, but I don't think it was an SLR lens, wasn't it a range finder lens?

Anyway as for the op.. if you had a f1.0 lens with fixed focus...you know how small the area in focus would be.. if the focus was fixed...you'd be like..."okay, i best walk forward 1mm...oops..too far...here, let me borrow your tape measure..okay think i've got your eyes in focus now..oops, damnit, she moved...grrr...."

You'd hafta have the damn thing mounted on a rail or something lol.