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06-18-2016, 05:09 PM - 1 Like   #16
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QuoteOriginally posted by szffagier Quote
I'm not a pro just yet, so I'm still looking for my niche. I'd like to do landscape, astrophotography, interiors, environmental portraits... pretty much everything
If you are into this for the long-term, it may be worth considering whether the UWA lenses you buy today are full-frame compatible, or not.

Although many APS-C wide-angles will work fine on a FF camera like the K-1 in crop-mode or otherwise, FF and wide-angle do tend to go together.

At the moment there aren't many K-mount FF UWA's available new, aside from the SamYang 14mm and the Pentax 15-30. Either may be worth looking into if a FF body is in your future plans.

06-18-2016, 08:05 PM - 1 Like   #17
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I have four ultra wides: the DA 15, the DA 12-24, the DA 10-17, and the Samyang-derived Rokinon 10 f2.8. My top recommendation would be the DA 12-24, or, if you want to go wider and you like Sigma glass, the Siggy 8-16. But the fact is, you can't really go wrong with any of the ultra-wides available for the K-mount, although some are a little better than others. Get whichever one you think best fits what you want to accomplish in your photography and which you can afford. If astrophotography is really important to you, you might want to check out either the Samyang 10 2.8 or 16 f2.0. If you want to go really wide, but don't want fisheye distortion, get the aforementioned Siggy 8-16. If you don't mind fisheye distortion, get the DA 10-17. If you don't need to go quite so wide and want Pentax colors, get the DA 12-24. If you want flare control, superb contrast and color, and starbursts, get a used SMC DA 15. If you're cash-strapped, look for a used Siggy 10-20 f4-5.6 or Tamron 10-24. Lots of choices, but none of them are wrong.
06-19-2016, 01:43 PM   #18
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Thank you very much for such a great response everyone. It's very helpful!


There is one more option on the horizon:


Getting 8mm Samyang FishEye f/3.5 , and then when needed defishing the images. it's not a very complexed process, and after reading this I'm also taking this under consideration:
The Best Method of Defishing a Fisheye Photo – Lonely Speck


what do you think? is there a loss of quality after defishing? I can't really find any useful information on this
06-19-2016, 06:04 PM   #19
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QuoteOriginally posted by szffagier Quote
what do you think? is there a loss of quality after defishing? I can't really find any useful information on this

Unavoidable in those areas where the distortion is corrected. The level of acceptability is up to you. A lot of people seem to do it for selected images.

06-19-2016, 06:12 PM   #20
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QuoteOriginally posted by szffagier Quote
what do you think? is there a loss of quality after defishing? I can't really find any useful information on this
There is a bit of a learning curve to climb. Rectilinear projection (as with the Adobe profile for Samyang 8mm FE) is about the worst that you can use - you quickly lose any sharpness and resolution at the frame edges. The Fisheye Hemi plugin is not too bad as a starting point - Panini type projections such as that usually look the best. The trick is to be careful with the original shot composition and to be prepared for some heavy cropping ...








06-19-2016, 08:36 PM   #21
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QuoteOriginally posted by szffagier Quote
what do you think? is there a loss of quality after defishing? I can't really find any useful information on this
You can check out my experiments with defishing HERE.
kh123... probably knows more about technical aspects than I, so note his comments.

You actually can do quite a bit in Lightroom in the new Transform section of the latest LR CC.
  • Before you use this Transform section, you should first use the Lens Correction section to deal with lens distortions. For most of my lenses, enabling the automatic Profile Corrections does a pretty good job. You do have the option of adjusting the amount of distortion and vignetting to get the right look. I can even do a fairly decent job of defishing fisheye lenses with this. (Under Lens Correction is also where you can enable and adjust chromatic aberration removal.)
  • Once the lens correction is done, then go to the new Transform section to correct perspective distortion. It works quite well, and it is rather intuitive. You can use the Auto or Full to have the pic corrected automatically, but using the manual or Guided gives more control. It's basically a matter of drawing two or more parallel and/or perpendicular lines, and the photo is corrected. You still have the option of manipulating everything using the manual sliders.
  • Before this feature was added, I had purchased DxO Viewpoint 2. That little program offers a lot of control, and can do a bit more than the new Transform in CC, but it only works with TIFF or JPG (which means that my DNG files need to be converted first). Result: I think I will be able to do most of my work in LR CC using Lens Correction and Transform, but if I really want to do something special, I'll jump over to DxO Viewpoint.
As for final results and quality: Defishing a fisheye works with software processing much like an UWA rectilinear lens does with the physical characteristics of the lens elements. The main difference is that with the fisheye, you're going to chop off a lot of edges to get a field of view and perspective similar to the rectilinear. With the UWA rectilinear, you may get soft borders since a lot of light is being bent to gain the rectilinear view. In general, what I have found (and someone can correct me), the end result of a defished fisheye and an UWA rectilinear may be similar, but you usually have more pixels of detail with an UWA. Depending on how much enlargement you do, however, either the FE or the UWA may work perfectly well.
06-20-2016, 01:48 AM - 1 Like   #22
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The basic problem with defishing vs using a ultra-wide lens is that you are never sure what you'll end up with after defishing as you shoot. You can follow some basic rules - keep horizon and converging lines at the vertical centre of the frame etc. - but you can afford to be much more creative when you can actually see what you are going to get by looking through the viewfinder.

As for defishing FE - often you are better off using a longer focal length lens (say 16 or 18 mm on APS-C) and stitching together a few shots.

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