Forgot Password
Pentax Camera Forums Home

Show Printable Version Search this Thread
04-25-2011, 07:00 AM   #1
Clavius's Avatar

Join Date: Feb 2011
Location: De Klundert
Photos: Gallery
Posts: 4,122
Which super/ultrawide

My arsenal of lenses is still missing a very wide lense.

I like the fisheye-effect, but not always. So, I'm looking for a zoom that has the fisheye-effect on the short end and just a normal very wide effect on the long end.

I am told that the Pentax DA 10-17 has these properties. But I've been very impressed with Sigma's 10-20 pics too.

Which of the two performs best? And which one would serve my needs the most? Do they both have the fisheye effect on the short end? Any other brands that do the same trick?

Thanks for your help.

04-25-2011, 07:25 AM   #2
Loyal Site Supporter

Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,107
Morning, Your choices are 2 - rectilinear or fisheye, however a hybrid does not exist. The 10-17 is a fisheye, however at the 17mm end the amount of fisheye distortion is not that pronounced. At 10mm its field of view is about 180 degrees, however at 17mm the FoV is down to 100 degrees wide. If you shoot landscape it may appear somewhat gone, however if you shoot architecture, you will soon notice that it is still there.

Which one - its impossible to have one lens with a bit of both....

04-25-2011, 07:30 AM   #3
Clavius's Avatar

Join Date: Feb 2011
Location: De Klundert
Photos: Gallery
Posts: 4,122
Original Poster
Ah, so I'm comparing appels with pears? (As we say in Holland.)

The Sigma won't even have fisheye distortion at the 10mm? I certainly see the advantage in that... but I want to experiment with the fisheye effect too.

I think I should buy the one I'm going to be using the most, and rent the other some time.
04-25-2011, 09:25 AM   #4
Inactive Account

Join Date: Mar 2007
Location: Long Island, N.Y.
Photos: Gallery
Posts: 1,124
One of the nicest points about the Sigma 10-20 is that it has very little distortion at the wide end and almost non at 20mm.

04-25-2011, 10:03 AM   #5
panoguy's Avatar

Join Date: Sep 2007
Location: Washington, D.C.
Photos: Gallery | Albums
Posts: 3,290
Keep in mind that the Sigma at 10mm is nowhere near as wide as the Pentax at 10mm, entirely because it doesn't have the fisheye distortion. The distortion is only there to fit 180 (diagonal) degrees of view into a cropped-sensor.

(I use the 10-17 all the time, and it even "undistorts" pretty well)

Last edited by panoguy; 04-25-2011 at 11:43 AM.
04-25-2011, 10:13 AM   #6
Veteran Member
KxBlaze's Avatar

Join Date: Feb 2010
Location: California
Photos: Gallery
Posts: 1,594
I cannot speak on the Sigma but the 10-17 is a really good and fun lens to use. I would go with that one because of the fish-eye you want to experiment with and you can use the 17mm end for your ultra-wide use. The 10-17 will probably come the closest to filling your needs but like others have said there is not one lens that will fill it completely.
04-25-2011, 10:16 AM   #7
Clavius's Avatar

Join Date: Feb 2011
Location: De Klundert
Photos: Gallery
Posts: 4,122
Original Poster
Thanks for all the replies!

I had forgotten about undistorting with postprocessing software. I think I definetely prefer the Pentax fisheye.
04-25-2011, 11:12 AM   #8
Veteran Member

Join Date: Mar 2009
Location: Chicago suburbs
Photos: Albums
Posts: 848
I own both. I use the Sigma 10-20mm more. De-fishing the 10-17 is an interesting option, if somewhat flawed. I tried de-fishing and I don't bother with it any more. When de-fished, the image has a strange shape and must be cropped to make a rectangle. The de-fishing software that a tried seems to soften the image somewhat. Add that to image crop and the Sigma is sharper. I'm not saying the 10-17mm is soft, just that de-fishing makes it so, it is great as a fish eye lens. Get both when you can, they are not interchangeable.

04-25-2011, 11:40 AM   #9
Forum Member

Join Date: Apr 2011
Posts: 54
Have you looked at the 10-20 sigma club in this forum? I spent about a week looking at the photos and reading from this forum and that is why I am buying the sigma 10-20 this week. I am going to Europe for a month and wanted a good wide angle with good speed for low light indoor situations and from what I have been able to find out this is a good one.
04-25-2011, 12:58 PM   #10
Loyal Site Supporter
TER-OR's Avatar

Join Date: Apr 2009
Location: Dundee, IL
Photos: Gallery | Albums
Posts: 5,834
The 10-17 is a lot of fun. I bought one after renting it for two weeks over the holidays. It's nice being able to take pictures of subjects like dogs or kids running around right at your feet. Zoomed out to 17mm it's still a bit fishy but it is a fisheye lens, after all.

The 16-45 has a bit of fisheye when wide-open and performs pretty well indoors. I'm sure the 10-20 will be better there if you really need wide-open. I often have it on the camera but am thinking of the 18-135 or the 17-70 as an upgrade because it seems a bit soft on the K-5. It's great on the K-10 so maybe it's me....

I'm going to rent the 21mm Ltd for a couple weeks in May, and anticipate a good experience indoors and out.
04-25-2011, 02:25 PM   #11
Veteran Member
RioRico's Avatar

Join Date: Jun 2008
Location: Limbo, California
Posts: 11,264
I use various ultrawide / fisheye (UW/FE) lenses, but no Sigmas. Keep in mind that various fisheye and rectilinear projections are possible, so it's not just apple'n'pears, but apples vs peanuts vs tofu vs beef jerky. Also keep in mind that fisheyes can be full-circle or frame-filling, and that rectilinear lenses DO distort, albeit pleasingly. A round image is optically least distorted. Here is my overview.

* Kenko 180 Degree Fisheye adapter, variously badged as Vivitar, Spiratone, others. I mount this on a 35-70 or 35-80 zoom. At ~40mm or less, it is full-circle. At ~60mm or more, it is frame-filling. It MUST be stopped down and secured, and edges are still unclear, but it is fun to experiment with various fishy projections.

* DA10-17 zoom. This is the lens that drove me to Pentax in the first place. It is great, and fun, and tricky to use -- at the wide end, every shift of mm or degree makes a difference -- but it's a great way to exploit angles. Just don't use it in an evergreen forest; all those trees falling-in on you can be frightening!

* Zenitar 16/2.8. It's quite fishy on FF, slightly fishy on APS-C. Equally fishy and much faster than the DA10-17 at 16mm, f/2.8 vs f/4.5, so I use the Zen more indoors. (On my last long journey, the Zen was my second-most-used lens after the DA18-250.) The Zen de-fishes to a rectilinear equivalent of 12mm.

* Tamron 10-24. I must have a good copy, 'cause I'm happy with it at all focal lengths and apertures. (Some users go through multiple Sigma 10-20's before getting a good copy.) It's still slower than the Zenitar, but is good for small spaces, and places where angles aren't as problematic as with a fisheye.

These are all different tools with different functions. The Kenko for wild effects and experimentation. The 10-17 to exploit angles, and for small rounded spaces. The Zen for indoors, or where straight margins don't matter. The Tammy for shots where straight margins DO matter, and for street shooting at the long end. All will be taken on my upcoming journey.

Remember, I said above that rectilinear wide lenses distort? This is very obvious, even at 24mm. Put a good 24 on your camera, pan about, and notice the margins stretching and shifting. That, and fisheye 'distortion', are just the consequence of putting round pegs into square holes: trying to project globular reality onto a flat surface. The best way to avoid this is with a curved-field lens projecting onto a curved-frame sensor. With advances in spray-on semiconductors, such is not impossible to achieve. But don't hold your breath whilst waiting for those to be sold at WalMart.
04-25-2011, 08:46 PM   #12
Loyal Site Supporter

Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,107
You have received a very thoughtful set of replies. Over the last several years my view has changed a bit on the topic. On the way in to this topic, my view was a wide as possible, and that is still true (for the most part) - when it fits the context of the scene being shot. The flip side of this is that not all scenes benefit from an extremely wide lens. The wider the lens, the more it pushes back the view in order to pull in the edges. So, even with little or no distortion, the scene tends to be push off in the distance - more than you may anticipate.

I count myself very fortunate in having both the 10-17 and a 12-24. These two lenses are very complementary. Due to their differences (fisheye and rectilinear) their focal length designations do not begin to tell the entire story. Field of View (FoV) is a much better indicator/descriptor. The 10-17 has a FoV of 180 to 100 degrees, while the 12-24 has a FoV of 100 to 60 degrees.

The 10-17 has almost a Jeckel and Hyde personality. Depending on how you frame the picture, you can put the bend just about anywhere in the scene. You can have a perfectly level horizon at 10mm through 17mm. However by zooming out, in certain settings you can essentially remove the fisheye effect. Landscapes and natural settings are much more forgiving in this respect, since the eye can not usually detect the fisheye distortion. However shoot architecture, and due to the usually linear nature, you have the fisheye bend. Architecture with curves build in, and your back to the eye having a more difficult time to detect it. Its a really fun lens to shoot with. However, too much of a good thing can be wearing. The 10-17 in order to pull in the edges, does push the center and the entire scene back away from the camera. At times you wonder - why you used the lens. Conversely, in tight spaces, or shooting extremely close to objects - you are able to pull in everything. Another instance where the fisheye was the absolutely only choice, was one of my favorite shots. An aircraft carrier and a destroyer along side during an underway replenishment at sea. To get the shot it had to be 180 degrees in a single shot due to the motion of the ships (impossible to stitch). Now, I have tried several times to defish this shot, and have found it difficult to due - since defishing distorts angles, and the destroyer is "pulled" and appears un-natural. So there are limitation to everything.

The 12-24 I choose over the 10-20 because in my opinion it had less distortion. There are times when the 12-24 is just too wide and I find that stitching a 28 or 31 provides a good balance of IQ, sharpness of detail, with an acceptable width. The 12-24 is wonderful to frame the overall view, while there are opportunities to stitch other aspects of the scene with greater detail. The 12-24 is a very sharp lens, but the sensor only has so many pixels and coupling the 12-24 together with other focal lengths helps tell to full story of what you are seeing and may want to convey.

Stitching - just because you have an ultra wide angle lens, does not necessarily mean that stitching is not appropriate. I wanted to see if I could stitch with a fisheye, so I choose sitting under a shade tree. Actually it turned out to be the perfect setting since I wanted to emphasis what was both around and above me. Since it was not architectural it worked great. I would also believe that it would work in a lot of large interior areas (cathederals in Europe) with a lot of arches and curved non uniform surfaces.

Anyway - ultra wides are an interesting topic. There are a lot of ways to apply them, especially when you have two distinctly different lens types (fisyeye and rectilinear) from which to choose. In the long run you will probably get more use from rectilinears than fisheyes. That said, several of my favorite images are from the fisheye.....


  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, effect, pentax help, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Similar Threads
Thread Thread Starter Forum Replies Last Post
The Ultrawide comparison - Suggestions? DanielT74 Pentax SLR Lens Discussion 5 02-01-2011 03:56 PM
ultrawide QC -- good vs bad copies RioRico Ask B&H Photo! 8 12-20-2010 08:23 AM
Ultrawide Predicament RioRico Pentax SLR Lens Discussion 11 12-08-2010 09:14 PM
Nature First Ultrawide Picture future_retro Photo Critique 3 07-30-2010 11:27 PM
Which Sigma ultrawide? MrCynical Pentax SLR Lens Discussion 6 04-23-2010 01:54 PM

All times are GMT -7. The time now is 10:53 PM. | See also:, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]