Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-20-2013, 04:56 PM   #31
New Member




Join Date: Feb 2013
Location: New Hampshire
Posts: 12
Original Poster
QuoteOriginally posted by lytrytyr Quote
Thanks lytrytyr, I had not seen that review and I really like the the way they demonstrated the software - very helpful

02-20-2013, 08:33 PM   #32
Loyal Site Supporter




Join Date: Jun 2009
Location: Tumbleweed, Arizona
Photos: Gallery | Albums
Posts: 5,102
QuoteOriginally posted by zdwagner Quote
What about using a fisheye and then correcting it in post? Does anyone here do this? I'm an idiot when it comes to knowing much about that particular thing, so does it, in the end, afford you a greater expanse of view after correction, or effectively the same? For instance, would a corrected 10mm fisheye shot give you more of a view than a 10mm rectilinear?
QuoteOriginally posted by lytrytyr Quote
My other machine is under the weather right now with all of my images - needs a new graphics card. I did want to add a couple of items into the defishing discussion, that I came across from the school of hard knocks. For the most part, you shoot an image with a fisheye, then wind up defishing - usually things go all right. The key is to understand what the defishing process does - and the results that you wind up with. The fisheye lens is usually so wide that usually there is more than enough for cropping. That said, if your intent is to defish, then I would suggest that you shoot with an eye towards 1) framing and 2) perspective. I went searching for some examples and came across this....Its not exactly using the 10-17, but that is not the point. The point is that when you shoot with a fisheye with the intent of defishing, you want to pretty much center the main object with sufficient framing so that when you defish you can crop accordingly. The Photozone example is excellent and is a wonderful illustration (in particular how defishing affects perspective). However, it was shot with a lot of boarder around it, so that it could be cropped. I once took a shot (one of my best ones) while out at sea. I needed the entire 10mm to capture what I wanted. Quite a while later I decided to see what it looked like defished. I did not like it, primary because I did not have enough boarder around the initial subject (since I needed edge to edge).

Also, scroll down to the bottom of the above link. Take a look at the guy's shoe. Objects out on the edge look just fine when shot. When defished, they sometimes do not look so fine. Defishing concentrates on getting the center looking "right", while expecting that the stuff out on the edges probably will be cropped off.

So, the bottom line is that when using a fisheye for an ultra-wide is wonderful. The lenses have a lot going for them, however they are a specialty lens. When you defish, you are going to loose a reasonable amount of that extra width - in terms of Angle of View.

Also, between the car and the interior shots. Curved surfaces are treated pretty kindly by the fisheye. Straight lines and "square" items - intersecting lines, right angles do suffer. The observers eye knows that the lines are straight and thus becomes very noticeable. Curved surfaces, tree branches, natural items with natural shapes are treated much more gently, because the eye can not predict what it should be seeing.


Last edited by interested_observer; 02-20-2013 at 08:41 PM.
02-20-2013, 08:46 PM   #33
Site Supporter
SpecialK's Avatar

Join Date: Dec 2006
Location: So California
Photos: Gallery
Posts: 14,852
QuoteOriginally posted by stormtech Quote
This is a great comparison - thanks for sharing it. I do own the 10-17 and have the 12-24 on my wish list. Your comparison really helps in making my decision.
Yay! Someday I may go get that 10mm shot, though the building is now tan color, and I'm not even sure how to merge the images anymore :-)

QuoteOriginally posted by GibbyTheMole Quote
I'm glad I pulled the trigger on a Pentax DA 10-17 a couple of years ago. It's a blast to shoot with, and if I may fire off my opinion, it blows away any other wide angle I've owned.
It's...da bomb!

Last edited by SpecialK; 02-22-2013 at 06:07 PM.
02-21-2013, 09:11 AM   #34
Senior Member




Join Date: Feb 2013
Location: Albuquerque, NM
Posts: 136
Good stuff, interested_observer! Love the article you found, very informative.

02-22-2013, 04:47 PM   #35
Loyal Site Supporter
TER-OR's Avatar

Join Date: Apr 2009
Location: Dundee, IL
Photos: Gallery | Albums
Posts: 5,799
I have the 10-17, and it's very cool. It's small enough to pop in the bag when going to family events etc. Fisheyes are fun.
I rented the Sigma 8-16mm and really, really enjoyed it. The perspective is completely different.
I've read lots of good feedback about the 10-20, but that Sig 8-16 is very tempting.

Sigma 8-16: note at wide 8mm how the edges give an illusion of motion.


Sigma as landscape lens:


10-17 at 10mm classic fisheye fun:


10-17 wide open you really have to remember where your fingers are...
02-22-2013, 05:06 PM   #36
Senior Member




Join Date: Feb 2013
Location: Albuquerque, NM
Posts: 136
Very cool and fun photos, TER-OR. I sadly returned my Sigma 8-16mm (and have the 10-20mm on the way). Not for any fault of the lens, but for two specific reasons. One is that it's much easier to mount filters on the 10-20mm. I could make it happen with the 8-16mm with the right equipment of course, but to me the 2mm aren't worth it. But the more important reason is that the 10-20 is almost $200 cheaper (and I found one used for $412 on Amazon, so more than $200 cheaper than the *new* 8-16mm), and I'm getting the cash together for the DA* 300mm f4. So the trade was worth it to me.
However, I did like the 8-16mm. I think with such a wide perspective, it takes a lot of practice to begin to get truly great photos with such incredible expanse. Often photos that wide can come out looking odd and what they gain in interest is often lost in the crazy distortion you get at the edges, which can make everything look very flat toward the edges of the frame.
However I did have the 7-14mm (14-28 equiv) for my m4/3 system for a while, and loved it. Was it necessary, no, but it did net me some dramatic shots that other lenses simply couldn't have.
In the end the wide lens I ended up keeping and loving for m4/3 was the Olympus 9-18mm (18-36 equiv). The 9mm (18) was just wide enough for decent drama if I wanted it, and it kept shots from looking too 'gimmicky'. Obviously the Sigma 10-20mm will be in between these, at roughly 15mm equiv at the wide end, which I think is plenty. Hopefully the optical quality of the 10-20 is close to the 8-16; most reviews seem to think they are relatively close.
But if you can use it well, why not go as wide as possible?

PS- Your dog is awesome.
02-24-2013, 05:58 PM   #37
Pentaxian
kh1234567890's Avatar

Join Date: Sep 2010
Location: Manchester, UK
Photos: Gallery
Posts: 2,405
QuoteOriginally posted by Moondawg Quote
Anyone have any examples of eliminating fisheye via software using an ultra wide fisheye? Or is does that cause other issues? Sorry if I missed that in the posts, I used my computer last night to post and am now viewing the replies on my phone.
You can de-fish fish-eye shots but you lose resolution in areas where you are stretching the original image. Laws of optics being what they are, you can never de-fish perfectly.





02-25-2013, 11:33 AM   #38
Senior Member




Join Date: May 2010
Posts: 113
of course you can defish perfectly. you can even change center of a frame to any point you want and select any rectilinear optical length you want.

if course you will only see part of the frame that you'd see with that length rectilinear lens.

the above photo is NOT defished. on defished photo, straight lines bent on fisheye look straight, and we don't see that here.

02-25-2013, 11:53 AM   #39
Moderator PEG Judges
Kerrowdown's Avatar

Join Date: Aug 2008
Location: Highlands of Scotland.
Photos: Gallery
Posts: 32,562
QuoteOriginally posted by Moondawg Quote
Rectilinear vs Fisheye
I must admit for me it would be rectilinear, as I've said elsewhere "Currently having an illicit affair with my SMC Pentax-A 15mm F3.5", which I hasten to add is rectilinear

Last edited by Kerrowdown; 02-25-2013 at 12:16 PM.
02-26-2013, 04:30 PM   #40
Pentaxian
kh1234567890's Avatar

Join Date: Sep 2010
Location: Manchester, UK
Photos: Gallery
Posts: 2,405
QuoteOriginally posted by olenl Quote
of course you can defish perfectly. you can even change center of a frame to any point you want and select any rectilinear optical length you want.

if course you will only see part of the frame that you'd see with that length rectilinear lens.

the above photo is NOT defished. on defished photo, straight lines bent on fisheye look straight, and we don't see that here.
You mean something as ugly as this ?

The possibilities are endless


Reply

Bookmarks
  • 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!
decisions, fisheye, k-30, k-mount, lens, pentax, pentax lens, shots, sigma, slr lens, software
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fisheye Face-off: Pentax 10-17mm vs Samyang/Rokinon 8mm darrenleow Pentax SLR Lens Discussion 66 04-28-2015 05:38 AM
Comparing samyang's 8mm fisheye and 14mm rectilinear wshi Pentax SLR Lens Discussion 1 01-25-2011 11:49 PM
Opteka Fisheye Adapter vs. Opteka 6.5mm fisheye goldenarrow Ask B&H Photo! 2 08-11-2010 04:04 PM
Rectilinear vs fisheye wide angle question PentaxPoke Pentax SLR Lens Discussion 23 09-03-2008 10:45 PM
Wide angle: rectilinear or fisheye? mikem Pentax SLR Lens Discussion 18 05-24-2008 09:48 PM



All times are GMT -7. The time now is 07:21 PM. | See also: NikonForums.com, CanonForums.com 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?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top