New roadmap?

There would be some kudos for producing a 50mm f1 that was actually available and i guess that some of the richer Pentax Users might well buy one.

Isn't the Leica one around £7000.00?

f numbers, or aperture values, are a measurement of the size of the hole that the light passes through in the rear of a lens, relative to the focal length of the lens.

That's also the only thing that I know for sure and I know there are tricks for that but I won't say anything about it since I simply don't know.

In fact it is the aperture apparent when looking through the front of a lens, not the actual physical dimension of the aperture, divided by focal length.

If it was the actual size of the rear opening a 300 2.8 would be a bit tough to produce! Hence the limiting factor is the diameter of the front element. If you look through the front of a long, wide aperture lens you will find the it appears to be the same width all the way through, even though physically it gets narrower.

[edited for typos]

I believe f-number is relative to the width of the beam of light.
So if you place the diaphragm at the place were the beam of light is add his smallest width you don't need a large aperture.

That's one of the trick you can do but the very basic of the f-number is focal length devided by lens diameter and you can't change that.

Focal length devided by diamter is so far as I know only applyable this simple with a single lens system

This is true unless you resort to the trickery which Zeiss used by incorporating a condenser like they did with their f/0.7 lens.

Here is another nice website with a lot of additional information on the Zeiss 0.7 lens and some other lenses which use the same technique.
I see no way why Pentax should not be able to produce a f1.0 lens after I read this website. The only downside would be the price. It will have a very high price I think.

Website (translated by Babelfish)

Good debate, but I repeat something I said a while back, why not a full range of F2.8 lenses, from 12mm through to 600mm - great for wildlife and for sure you'll know at F4+ it will be good, with SDM and IF.

60 to 250mm to me seems too big a range to cover to make a F2.8 HQ lens!

Peter

Peter f/2.8 tele lenses aren't cheap and the DOF would be quite small so if it is usefulll?
I really like how Pentax is keeping the price down, I looked up some priceses of Canon lenses and you near fell from your chair what the 300mm f/2.8 cost and the 400mm f/4.
Pentax isn't really aimed at top pro's so bringing out an 400mm f/2.8 of £6000 wouldn't sell so good I think. I'm sure that some would want one but not at that price

You are forgetting the Z1, Z1P, and perhaps a number of others.

G

I recall when they brought out the 50mm 1:1.2 (much lusted after) that it was the fastest lens they could make in the K mount. Mind you, with a smaller image circle, perhaps a faster lens could be made.

But the problem with all these pie-in-the-sky ideas is that nobody will pay the enormous prices that such lenses would need to be sold at.

G

It begs the question of whether we would prefer Pentax to spend their R&D money on esoteric lenses that few will buy, or on superb lenses that are practical and within our budget.

I don't need an f/1 lens, or even an f/1.2 for that matter.

The MZ-10 could allso set the aperture from the body. I tried out my 16-45 on it without problems, sadly that camera is dead. The internals were a little cheaply built though (plastic fantastic...)

While on the 50 f/1.2: A shop here in Copenhagen I dropped into today had a second hand for 2000 DKR (because of the week Pound that will be some 225 for You) Now I don't NEED it but I am tempted. It looked like new. What I do NEED is to sell some of my other old lenses first

But I agree with You, John. I am happy with Pentax as long as they continue what they are doing know (lens wise) - high qualiy stuff I can afford. When I bought my first digital a few years ago I chose to stick with Pentax because of the lenses (mainly the limiteds)

you can't make a conventional 50mm f/1.0 prime in Pentax K, but you may be able to be clever.

An f/1.0 50mm just has to have an entrance pupil 50mm across, the size of the rear element only scales relative to this if you are just taking the same design and scaling up. My 300mm F2.8 has an entrance pupil diameter in excess of 100mm.

I don't know, I'm not a lens designer, but it seems to me that enough R&D ought to be able to sort out the light path to make a 50mm f/1.0 possible.

So far the only possibilities I can summise are...

Pentax are going to produce lenses shaped like fingers (unlikely).
Pentax have decided that digital has had it's day and 35mm is coming back (also unlikely).
Pentax are making FF (possible).
There are the new WR lenses (possible and quite exciting).
Pentax are returning to 645 (possible and very exciting).

And my favorite...

Those crazy Dutch boys are having a laugh!

Does anyone else think we should all be out taking photographs?