[juanma_1]

The Sigma 15 mm f/2.8 EX DG delivers very good results in my K-1, after correcting distortion in Lightroom.[COLOR="Silver"]

[rawr]

after correcting distortion in Lightroom.

Raises a good point. Any discussion of wide-angle lenses should probably always mention if the lens has good correction profile support (geometric distortion, vignetting, CA correction, extras like deconvolution) available in the software of your choice (ie Lightroom, Capture One, DxO Optics Pro), particularly for some fields of photography (eg architecture, real estate etc) where corrections may be critical.

[ScooterMaxi Jim]

I want a wery wide angle lens for my fresh new K-1, and i just need to confirm:
- Samyang 14 mm is very "fishy"
Am I correct?

What constitutes rectilinear vs. fish-eye is open to interpretation, frankly. In fact, the 14mm Samyang is declared as a fisheye in bold letters on my Bower version packaging (same exact lens as the Samyang). At what point a lens becomes fisheye has no neat line of demarcation. In fact, most UWA lenses have substantial barrel distortion. If you object to a somewhat fishy look, the Samyang isn't for you. The correction requires a more advanced program - such as Picture Window Pro - to easily handle the complex mustache distortion. I do that for buildings, but the vast majority of situations look more realistic "uncorrected." Much like the even-fishier 8mm Samyang with the very useful stereographic projection (a mild, natural looking fisheye perspective).

The "lowest" distortion (most rectilinear) UWA FF lens available in Pentax K-mount most likely is the Sigma 12-24 (original design). Very good if you find a properly centered copy. As for using, UWA crop lenses on the K-1 - why bother? You'll get better results on the K-3 series because the body and lens are properly matched. By the time you drop out the virtually unusable K-1 areas, you have far fewer pixels to work with than the K-3 series.

[clackers]

What constitutes rectilinear vs. fish-eye is open to interpretation, frankly. In fact, the 14mm Samyang is declared as a fisheye in bold letters on my Bower version packaging.

I have the 14mm Samyang, Jim, and at 115 degrees FoV, it's nowhere near 180 degrees.


If I ordered a fisheye and received that, I'd want a refund.


Bower might put that on their box, but no one else makes that mistake.

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Last edited by clackers; 06-20-2016 at 10:06 PM.

[Digitalis]

you might extend your search for one of these:



The Sigma 15-30mm f/3.5-4.5 DG - tricky to find on the second hand market, even harder to find a centered copy.

[ScooterMaxi Jim]

There is no right or wrong regarding the fish-eye terminology, as no official definition has been agreed upon. Some people feel an honest fish-eye has to provide a 180 degree diagonal, but most would disagree with that as an absolute definition for photographic purposes - especially these days with so many FF lenses used on crop bodies. For instance, the Q 03 was introduced as a 160 degree fish-eye (although the newer body with a larger sensor probably allow for 180 degrees - but they came quite a bit later).

My favorite explanation of the various UWA projections comes from Thoby - Various lens projections

As for our beloved Samyang 14mm, our shared UMC formulation (few of the original design reached market) indicates complex barrel distortion of 7.2%, according to Lenstip. Here's the analysis, and chart:
Samyang 14 mm f/2.8 ED AS IF UMC review - Distortion - LensTip.com

Few would disagree with the OP's observation that it is quite fishy, but I agree with you that to call it a fish-eye - as Bower has done - creates confusion.

[NaClH2O]

I want a wery wide angle lens for my fresh new K-1, and i just need to confirm:
- Sigma 10-20 f3,5 covers FF from 14mm
- Pentax 12-24mm covers FF from 16 mm
- Samyang 14 mm is very "fishy"
- Pentax D FA 15-30 is expensive
Am I correct?

There is also the Tamron 14mm aspherical, which is rectilinear. Official name is Tamron SP 14mm AF 1:2.8. As the name suggests it's a F/2.8 lens. I just got my K-1 so I haven't shot with it on that body but here is a link to a bunch of shots taken with my K-3. click here.

[pinholecam]

Samyang 14/2.8 is cheap and good.
Sharp to the edges stopped down to f11.
Just make sure you get a good copy.
Mine is spot on at the infinity mark.

The filter has to be a 150mm size anyway for this FOV, and there are quite a few of such holders out there. (I'm using the Haida)
Distortion is not an issue unless one primarily takes architecture, and even then, there is a LR profile, which does well enough.
The downside to the distortion is that not all RAW processing software can take care of it as well as the LR profile.
I do run into so problems if I use RawTherapee or PDCU for example if processing for pixel shifted files shot with the lens.


K1+Samyang 14/2.8


Kintamani, Bali





K1+Samyang 14/2.8

[banep]

Pentax 10-17mm fisheye works very well with FF from 14mm to 17mm .. Wide enough.. and its only around $350

There is a small hint of vignetting @14mm. Looks good from 14,5mm to 17mm. Fisheye only in that range with K-1 in full frame mode.

[anakhaled]

The Samyang 14mm works great on it.

[Skewed]

I've tried my Pentax 12-24 on my K1 in FF mode; while the vignetting is pretty much gone at 18mm, off-center distortion is horrendous (at least to my eye) when the subject is not perpendicular to the lens.
I'm considering the Samyang 14 as a cost-effective alternative, but I don't know if I would use it enough to justify the purchase.

[Ascencio]

Irix 15mm is pretty good.

[anakhaled]

Actually, I mainly use my K-1 for landscape with two lens
Panagor 24mm f2.5 and my favorite lens SMC Pentax-F 28mm F2.8. I was very lucky to get a copy of this lens, It sharp right from f2.8. I shoot a lot of cityscape, city night, and long exposure stuff. Sample image below is at f11, focus at infinity and it is very sharp.
[IMG][/IMG]

[TTQ225]

The Sigma 15 mm f/2.8 EX DG delivers very good results in my K-1, after correcting distortion in Lightroom.[COLOR="Silver"]

I just bought this lens and it works very well on K-1. It's pretty sharp, with excellent colors and contrast. Almost no CA or flare even when shot directly into the sun. The fish eye distortions can indeed be corrected in LR CC using this lens' profile. However, the best results for corrected images are achieved when it's a landscape shot with lots of open space. It sometimes does not even require correction for this type of images. When image contains near walls like interior shots, the corrected image might look a bit weird. I think for interior shots it's better to leave image as is and not to correct it.

[gaweidert]

I have a Polar (Samyang) 18-28mm lens that is left over from my film days. It actually works pretty good on my K1 too. Kind of a funky lens. The front element group wobbles a bit but it doesn't appear to affect image quality. Not a great lens, but pretty good. It cost me all of $120 US at the duty free shop at Kimpo Airport in Seoul, Korea in 1993 or so.