[MJKoski]

Yeah, Sigma 20mm is the only solution but...oops. No K-mount.

Now it seems that Leitax conversion of Distagon 21mm is the only way to get optically passable ~20mm prime.

[D1N0]

Yeah, Sigma 20mm is the only solution but...oops. No K-mount.

Now it seems that Leitax conversion of Distagon 21mm is the only way to get optically passable ~20mm prime.

There is plenty of legacy glass: 20mm Lenses - Pentax Lens Reviews & Lens Database

[MJKoski]

How many are usable on 36MP sensor wide open for night photography purposes? None.

[D1N0]

Why ask a question if you are answering it at the same time. I am getting fed up with your trollish posts

[Nass]

Now it seems that Leitax conversion of Distagon 21mm is the only way to get optically passable ~20mm prime.

Should be exceptional, would be interesting to see your results from it. That's a hell of an optic.

And yeah, what D1N0 said. If you bought into Pentax then maybe it's better just to make the best out of it. If Pentax is problematic for you, just change brand. Sarcastic posts like that don't go down well.

[MJKoski]

Not until I know D820 has tilt screen. Until then K-1 has to do.

[biz-engineer]

How many are usable on 36MP sensor wide open for night photography purposes? None.

We can anticipate your comments. It's always negative.

[MJKoski]

I just write things I have experienced or seen. I can make my photos with any modern system, be it m4/3 or 645Z. Now I evaluate pentax system and so far it has failed on lens front. Only old lenses passable for modern hi-MP sensors are old supertelephoto lenses, macros and very few special wide angles like 21mm Distagon C/Y version.

Things would be drastically different if K-1 had 12MP A7s sensor. It has not. It requires wide aperture lenses for night stuff and old K/M whatever will not budge stopped down to f/5.6 or such to gain good enough resolution across the field.

[jeffshaddix]

Honestly those two reviews are pretty positive. Hopefully lenstip or photozone will get hold of a copy soon.

I too am considering either the Zeiss 21 conversion or this new samyang. I don't think the Zeiss is the holy grail people sometimes claim it to be, but it is one of the best options for our system. I wouldn't be surprised if at f/2.8, this samyang showed similar enough performance to make it worthwhile.

[beholder3]

Should be exceptiona

It is meh if you prefer proof rather than sadly incompetent claims.

The Pentax and Tamron 15-30 outperform the Zeiss wide open quite seriously:
Tamron 15-30mm f/2.8 Di VC USD Lens Image Quality

On the idiot level let me add: The Zeiss sucks even more for long distance subjects. You know, on that level we can claim anything without proper comparable proof. Who cares for images, anyway.

Sigma 20 Art sucks as well, compared to the Pentax and Tamron 15-30:
Tamron 15-30mm f/2.8 Di VC USD Lens Image Quality
The only Art in there is to produce a shabby plastic prime that can not compete with a wide open zoom even when stopped down two full stops.

Now the question is: Who prefers made up claims without any substance to it and who prefers image proof?

[MJKoski]

So you have 15-30? It is technically capable (with clinical rendering) lens if you somehow get a working copy first. Then you add $1000 worth of filtering options.

This discussion was about ~20mm prime, not about double priced zoom lens.

Zf1 version of 21mm distagon can be found used at price of 20mm FA 2.8 lens.

[Nass]

It is meh if you prefer proof rather than sadly incompetent claims.

The Pentax and Tamron 15-30 outperform the Zeiss wide open quite seriously:
Tamron 15-30mm f/2.8 Di VC USD Lens Image Quality

On the idiot level let me add: The Zeiss sucks even more for long distance subjects. You know, on that level we can claim anything without proper comparable proof. Who cares for images, anyway.

Sigma 20 Art sucks as well, compared to the Pentax and Tamron 15-30:
Tamron 15-30mm f/2.8 Di VC USD Lens Image Quality
The only Art in there is to produce a shabby plastic prime that can not compete with a wide open zoom even when stopped down two full stops.

Now the question is: Who prefers made up claims without any substance to it and who prefers image proof?

@beholder3 I'm confused... unless I'm smoking the funny stuff it looks to me like the Zeiss outperforms the Tamron rather a lot at 20mm 2.8, just look at the corners

[MJKoski]

The Zeiss outperforms 90% of all ~20mm ff options there are. Both technically AND most importantly - in visually pleasing way.

[Na Horuk]

Man, has to be a hard, dark world where Samyang sucks, Zeiss sucks, Sigma Art sucks, DFA 15-30mm is overpriced and usually sucks, where D810 sucks, 5DIII sucks, Sony A7 sucks, Pentax K-1 is eh, but still sucks sometimes..
To some people, money really can't buy happiness. For me, I'm happy with a couple lenses under $100 lol, and with some skills and PP my photos seem to be sharp enough. Maybe one day I will get a pro photo job where I will have to make pin-sharp wide-aperture billboard prints for close viewing purposes, but until then, a couple Samyang primes and some Pentax M primes will do fine.
I'll look for a few more reviews of the Samyang 20mm. If it had the price tag similar to the 14mm, it would be damn near perfect

[thibs]

So you have 15-30? It is technically capable (with clinical rendering) lens if you somehow get a working copy first. Then you add $1000 worth of filtering options.

More trollish posting.