[motorhead9999]

So, I posted in another recent thread about switching to the K1, which I've decided on. So the question is: I need a lens(es).

To sum up my situation/desires, I've got 2 real needs: Landscapes/Astrophotography and sports/wildlife.

Clearly, the Pentax will be for the landscapes/Astro stuff. For my sports/wildlife stuff, I've decided to (at a later point down the road) to go with a Nikon D500. The Pentax crop line just doesn't seem to match up with the D500, especially in terms of frame rate. Yes, having two different systems of lenses will suck, but I think that's just how it's going to be.

So at the moment, being that this Pentax will be pretty much exclusively be a "wide angle" camera, I'll need the following focal lengths:
8mm (this is a low priority, but one I'd like to get at some point)
14mm (going to get the Rokinon F/2.8)
either a 20 or 24mm (which is the best focal length to get?)
35mm (sigma art 35mm f/1.4)

What are your thoughts?

*Edit: I should also ask the question about whether the 20/24mm item is even worth getting if I get the 35mm and the 14mm

[SD_Bob]

You should take a look at the Irix 15mm, which I got to replace my Rokinon 14. In my case the image quality is much improved, sharper and less distortion. There are two versions of the Irix 15, I got the lighter Firefly and seems to be reasonably sturdy. There is a heavier, and more expensive, all-metal version.

[biz-engineer]

15mm , 14mm , too wide for landscape to my taste. The most usable bang for the bucks is Samyang 24mm 1.4 (77mm filter thread) or Samyang 20 1.8, along with a DFA28-105. A 100mm square filter system can be mounted on both the 24mm prime and 28-105 with two different adapter rings. And with those on the K1 everything from nightsky to landscape is covered.

[alpheios]

I shoot landscapes with my K-1 and I use the Sigma 35mm and Pentax 100mm WR for that purpose. I'm still looking for a 20mm to complete my lens kit. The difference between 35mm and 20mm is pretty big. The wider you get, the more difference every millimeter will make. So a 20mm would make sense to fill the gap between 14mm and 35mm. But the question is why don't you just get the Pentax DFA 15-30mm? It will cover the wide end perfectly, has a very good reputation for astrophotography and will probably cost less than the three primes you have planned to get.

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Last edited by alpheios; 09-15-2017 at 11:18 AM.

[BullsOnParade81]

Why not get the DFA 15-30mm f2.8 ?

[motorhead9999]

Why not get the DFA 15-30mm f2.8 ?

I'll certainly look into it. Is that the Pentax rebranded Tamron lens?

[alpheios]

I'll certainly look into it. Is that the Pentax rebranded Tamron lens?

Yes it is

[Adam]

So, I posted in another recent thread about switching to the K1, which I've decided on. So the question is: I need a lens(es).

To sum up my situation/desires, I've got 2 real needs: Landscapes/Astrophotography and sports/wildlife.

Clearly, the Pentax will be for the landscapes/Astro stuff. For my sports/wildlife stuff, I've decided to (at a later point down the road) to go with a Nikon D500. The Pentax crop line just doesn't seem to match up with the D500, especially in terms of frame rate. Yes, having two different systems of lenses will suck, but I think that's just how it's going to be.

So at the moment, being that this Pentax will be pretty much exclusively be a "wide angle" camera, I'll need the following focal lengths:
8mm (this is a low priority, but one I'd like to get at some point)
14mm (going to get the Rokinon F/2.8)
either a 20 or 24mm (which is the best focal length to get?)
35mm (sigma art 35mm f/1.4)

What are your thoughts?

*Edit: I should also ask the question about whether the 20/24mm item is even worth getting if I get the 35mm and the 14mm

The Sigma 35mm is a great choice. I second the recommendation for the Pentax 15-30mm, as it's a nice all-in-one solution to your landscape needs. The Irix is otherwise a good alternative to the Samyang 14mm which many don't recommend for FF (though it's fine on crop). The Samyang 24mm F1.4 is also great if you decide to go down the prime route. Having that faster aperture could be really beneficial for astro shots, as I've found F2.8 to be too slow in many cases.

If you need to go wider (i.e. a fisheye), there's the old F 17-28mm, several manual options, as well as a roadmapped modern replacement for the F lens.

Full Frame Lenses | PentaxForums.com

[angerdan]

...the Pentax will be for the landscapes/Astro stuff.
...the Pentax will be pretty much exclusively be a "wide angle" camera, I'll need the following focal lengths:

• 8mm (this is a low priority, but one I'd like to get at some point)
• 14mm (going to get the Rokinon F/2.8)
• 20 or 24mm (which is the best focal length to get?)
• 35mm (sigma art 35mm f/1.4)

What are your thoughts?

Pentax D FA 15-30mm will give you WR, good image quality and silent AF.
Pentax FA* 24mm 2.0 will give you good image quality and lens correction too.
Pentax FA 31mm 1.8 Limited will give you good image quality and lens correction too.

For more options, take a look here:
Full Frame Wide Angle Lens List--20mm and Under - PentaxForums.com

[motorhead9999]

The Sigma 35mm is a great choice. I second the recommendation for the Pentax 15-30mm, as it's a nice all-in-one solution to your landscape needs. The Irix is otherwise a good alternative to the Samyang 14mm which many don't recommend for FF (though it's fine on crop). The Samyang 24mm F1.4 is also great if you decide to go down the prime route. Having that faster aperture could be really beneficial for astro shots, as I've found F2.8 to be too slow in many cases.

If you need to go wider (i.e. a fisheye), there's the old F 17-28mm, several manual options, as well as a roadmapped modern replacement for the F lens.

Full Frame Lenses | PentaxForums.com

Why not get the DFA 15-30mm f2.8 ?

Looking at some of the other options mentioned (Irix (), there's one appeal there for me. Their lenses would allow me to put a 100mm filter holder on their lenses, although it appears I'd need to get a new holder to accomodate the larger size (grrr...). Is anyone aware of a way to mount a 100mm filter onto that Pentax 15-30?

[Adam]

Looking at some of the other options mentioned (Irix (), there's one appeal there for me. Their lenses would allow me to put a 100mm filter holder on their lenses, although it appears I'd need to get a new holder to accomodate the larger size (grrr...). Is anyone aware of a way to mount a 100mm filter onto that Pentax 15-30?

Not sure about specifics on filters for the 15-30mm, but the irix does accept rear gel filters if you want to keep the package smaller.

[texandrews]

You should take a look at the Irix 15mm, which I got to replace my Rokinon 14. In my case the image quality is much improved, sharper and less distortion. There are two versions of the Irix 15, I got the lighter Firefly and seems to be reasonably sturdy. There is a heavier, and more expensive, all-metal version.

Yes. At least the distortion bit. Rokinon has complex distortion. It is reputedly sharper, but probably not by much. BTW, the heavier, all metal version is also weather sealed, of interest to landscape shooters, no? I am not knocking Rokinon/Samyang/Bower----I've had their lenses and they are quite good. The Irix is on another level, though. Has a user adjustable infinity adjustment screw as well.

[grispie]

For my sports/wildlife stuff, I've decided to (at a later point down the road) to go with a Nikon D500.

Just as a thought & depending on when a later point down the road is, for sure there will be a new crop sensor pentax that adresses that issue. At least i hope.

[Fcsnt54]

There is an irix 11mm that they say has no fisheye that comes in pentax k mount. Probably the widest that is offered

[Tas]

G'day,

I know it is normal to consider wide angles for landscapes, but telephotos can also do a brilliant job too. I suggest you drop by this thread: Post your Telephoto Landscapes! - PentaxForums.com and keep some longer lens options in mind as well.

But of course wide options do give you the grand vista landscapes and I am a fan of these too. And if you're up for getting into panorama images then normal and short teles become great options when the subject fits. But as you've asked about a wide angle lens option here's my 2c.

There's unlikely to be any 8mm options in K mount FF. The only one I"m aware of is a Sigma 8mm circular fisheye that you may struggle to find in K mount: DSLR Lenses, SLR Lenses | Camera Lens | B&H

To go ultra wide the Pentax 15-30 is a great option to keep up your sleeve. The WR and zoom range means it's a flexible option to consider. The filters for this lens will cost you money though. They require a 150mm filter system which means it's not cheap. There are options for this lens available from Benro, Lee, Nisi, Fotodiox and others so if you want filters for the 15-30 you can get them you just have to factor the costs into going with this lens option, or adopt a PP approach to images that would normally require filters.

I'm surprised that nobody has mentioned the future release of a Pentax wide angle prime, but there is apparently one coming. Breath holding is not recommended for this one though so to get back to the here and now if you are looking at really wide options then consider the Irix 11mm and the Laowa 12mm. Both appear to be viable options and are likely to get you as close to 8mm as you can on K mount. To get a feel for them and other alternatives have a look at this thread: ULTRA wide lenses (only FF equiv 12mm or lower) - PentaxForums.com I hope to get the Laowa 12mm at some stage, the zero distortion moniker should mean a good architecture option and less image space lost due to distortion correction, a problem out this wide (hence my earlier pano suggestion). However refer to posts by todd in that thread as he's found some issues with getting set up with the Laowa though now he seems happy with the lens he's got after returning the first one.

For more examples of the Irix 11mm and Laowa 12mm, check out these Flickr groups for each of these lenses:
Irix lens and photos | Flickr
LAOWA 12mm F2.8 ZERO-D | Flickr
IRIX 11mm f/4 Firefly & Blackstone | Flickr
Laowa D-Dreamer 12mm f/2.8 (ZERO-Distortion Ultra-Wide Prime) | Flickr

Good luck with it mate.

Tas