[eddie1960]

I agree Primes are better than zooms (at least most of the time)

Problem is the vast majority of the public buy zooms first and primes are secondary (the community here doesn't reflect the reality of the market at all)
it's easy for tamron and sigma to offer alternatives to us since they are selling them over much larger platforms. Our purchases in those lines are insignificant in comparison to even Sony users, never mind Nikon and Canon users

For Pentax to make a lens in the last few years it would have had to justify itself with very healthy sales potential to Hoya's bean counters. Now that Ricoh is running things they have a long list of lenses to develop IMO. I imagine like Hoya they will look first to the ones with the highest turnover potential, filling in later with the more exotic if share grows enough
As a category when you look at the market across all brands it becomes apparent that no-one currently considers a rectilinear UWA prime of any type a demand item since no-one has made one. Either this is because they can't be made for a viable price or with the advent of the large number of previously non existent UWA zooms that perform in many cases very well they don't think their is enough unique demand for a prime in the range
either way making one for a brand that commands at best currently about 4-5% of the worldwide market wit a largely notoriously cheap clientele is [probably a guaranteed money loser

[eddie1960]

Oh, I agree that an 8-10-12mm rectilinear for APS-C should be possible, since zooms that wide exist, and we'd expect that a corresponding prime should cost less to produce. So why hasn't it been done? My guess: Lensmakers just don't see a sufficient market. We can't force them to sell lenses that won't recoup their investment.

But maybe Pentax will surprise us. Maybe we'll see a DA*10/4. Whip out those sacrificial offerings, kids, and perform some rituals to propitiate the deities of applied optics and their bean-counting viziers. When you wish upon a star, etc.

a DA* 10 f5.6 even would be reasonable. either way though it would probably be one of the most expensive lenses in the line. I'm also guessing if they are planning a FF release they are also planning a range of needed lenses to support that release first since they can be sold across both platforms

[intjonmiller]

Pentax sees a market for 14, 15, 21, 31, 35, 40, 50, 50, 55, 70, 77, 100... I'm sure I missed some in there. The 31, 35, 40 span in particular is remarkable, as is the 14, 15, 21. 3 distinct primes in each small span. Surely with the popularity of the ultra wide zooms they cam be at least as profitable with one more prime at the extreme wide end.

[eddie1960]

14 was introduced quite a long while back as there was no wide option at all. the 15 was introduced to address some percieved problems with the 14 and also to complete the da ltd line
31/43/77 are lenses that have been in production since film days
21-40-70 were meant to provide a compact HQ line to complement the small camera designs
the 50's are old longstanding designed or revamps of them in a FL that sells very well and is cheap to make

Reality is many of the lenses you list could do with a modern update and the old models be dropped (31/43/77 for instance would all benefit from an update that adds rear coating and makes them WR)

The thing is it is cheap to keep older lenses in production and flesh out with some new lines optimized for the format. If the FA limited line wasn't as highly regarded and popular it probably would have been killed years back. Hoya over rationalized the lens line IMO and now we need a lot of lenses that are missing (ie no 24mm which makes a lot of sense on apsC and was also a great FF length) - edit and for every UWA prime you sell I would bet you could sell 6-10 FA24 revamped for Digital)

Producing lenses requires a big investment in tooling and line time. until the number of lens line production facilities increase adding more marginal lower volume lenses of any type is not likely to happen. But like I said as time progresses a lot of the wanted lenses will probably get into production. I just think we will see the fast sellers first (look atthe proposed lenses on the roadmap they all fall into fast seller categories the exception being maybe the 560 5.6 but that depends on what price it comes at - and the longer than 300 lens category is really slim so it is a needed soon lens. Pentax likely views the UWA zooms as good enough for now in that category. they have nothing to consider good enough for now in the super tele range

[intjonmiller]

I understand the differences in the existing prime lineup. My point is that, while primes generally sell in smaller numbers than zooms, that hasn't stopped Pentax from producing new ones even very close in fov to other existing models. The reason they did so is that the new ones differentiated themselves in a way other than just focal length. The same would be true of this proposed one if they did it right.

[lytrytyr]

As a category when you look at the market across all brands it becomes apparent that no-one currently considers a rectilinear UWA prime of any type a demand item since no-one has made one.

Here's a recent FF one from Zeiss:
Zeiss 15mm f/2.8 Distagon T* ZE Lens Review

[kenafein]

Here's a recent FF one from Zeiss:
Zeiss 15mm f/2.8 Distagon T* ZE Lens Review

Voightlander makes a 12mm/5.6.

[lytrytyr]

Voightlander makes a 12mm/5.6.

But in Leica M mount, not for DSLRs.

[RioRico]

But in Leica M mount, not for DSLRs.

Suitable for the GXR M-mountor though.

[lytrytyr]

Suitable for the GXR M-mountor though.

Absolutely. It might do better there than on the NEX,
where the edges looked weak in the Photozone test:
Voigtlander Ultra-Wide Heliar 12mm f/5.6 Aspherical II on Sony NEX - Review / Lens Test Report - Analysis

[Anvh]

Absolutely. It might do better there than on the NEX,
where the edges looked weak in the Photozone test:
Voigtlander Ultra-Wide Heliar 12mm f/5.6 Aspherical II on Sony NEX - Review / Lens Test Report - Analysis

Edges are the problem with most lenses on the NEX, the register is so short that the angle is to steep in the corners for the micro lenses on the sensor to redirect the light correctly on the pixels...
Ricoh had to use a special micro lenses on their Leica M-mount module but it seems to get decent result out of it.

[Laurentiu Cristofor]

Voightlander makes a 12mm/5.6.

That is the classic example of what lenses you can get for mounts with shorter flange focal distance.

[zapp]

1) Japanese manufactures can not make decent ultra wide primes - that's a quote, but I agree with it.
2) Nobody in Pentax land would want to pay for a decent ultra wide prime - my impression, but anything above $600 is called expensive here.
3) Cameras with mirrors in the light path are about to fade out - why introduce retrofocus lenses for dinosauer cameras. Manufacturers will wait for cameras without mirrors that allow for much easier optical design of wide angle lenses.
4) Most people do not buy prime lenses anymore. Pentax used to introduce a lot of primes - the last introdcution of a "missed" prime lens was long ago - let's not talk about several versions of 100 macro lenses, as well as 35 and 50 mm lenses or simple redesigns.

[eddie1960]

Here's a recent FF one from Zeiss:
Zeiss 15mm f/2.8 Distagon T* ZE Lens Review

$3000, made for FF. If a Pentax FF exists this would be UWA, So right now to use this it's a minimum $5200 investment in a D700 and the lens.
Currently Pentax has no lens that even approaches this price market. Add in that to make a 10mm for apsc and Pentax only would be a very limited market and likely would end up as a $4000 lens. what are the odds enough buyers would get it? If worldwide demand exceeded 25 lenses at that price for a K mount at the moment i'd be very surprised. If Ricoh succeeds in growing share and putting out a FF Zeiss will release this in K anyway(they have made K in the past and only stopped because the market got so small and they decided the manufacturing capacity was better devoted elsewhere

[lytrytyr]

Cameras with mirrors in the light path are about to fade out - why introduce retrofocus lenses for dinosauer cameras. Manufacturers will wait for cameras without mirrors that allow for much easier optical design of wide angle lenses.

Retrofocus wide-angle lenses do a better job of covering a digital sensor.
As the K-01 shows, you don't have to have a mirror flopping down between the two,
but mirrorless doesn't yet work well enough for serious action photography anyway.