Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
02-19-2020, 02:19 AM - 1 Like   #1
Pentaxian




Join Date: Feb 2015
Photos: Gallery
Posts: 12,177
Macro lenses best for panorama stitching?

Along with parallax errors, non-ideal lens distorsion is a pain for stitching images since not all distorsion follow a nice a,b,c distorsion correction model, resulting in some mismatch between frames.
Going into Pentax forum in depth lens review or ephotozine test results, we can compare lenses on how much optical distorsion they produce. With the idea of reproducing a 4x5 exposure area by stitching multiple exposures from a Pentax K1, the "crop" factor between 4x5 and full frame being about 3x, for a wide angle shot I'd need to use a focal length of 100mm (more or less depending on the final FoV of the stitched composition).

-> Pentax D-FA24-70 f/2.8:
- Pentax forum test: -0.1% @ 70mm
- ephotozine test: "70mm gives +1.45% pincushion distortion"

-> Pentax D-FA28-105 f3.5-5.6: -3.26% @ 28mm, -0.941% @ 35mm, +1.05% @ 50mm, +1.55% @ 70mm, +1.6% @ 105mm

-> Pentax D-FA70-200 f/2.8: 0.9% at 70mm, -0.6% @ 135mm, -0.5% @ 200mm ; problem with the DFA70-200 is the nodal point moves a lot from near front of the lens at 200mm to back of the camera at 70mm, very sensitive to the focal length and a pain to adjust in the field.

-> Pentax D-FA100 f/2.8 macro:
- comment from PF review "This lens is designed as a macro lens with a flat field of focus and no distortion and we were definitely not able to detect any distortion."
- ePHotozine/Imatest: 0.07%

-> Pentax D-FA50 f/2.8 macro:
- comment from PF 50mm lens comparison: "We are happy to report that none of the Pentax 50mm lenses had any measurable distortion."

-> Pentax D-FA50 f/1.4: comment from PF : "Most 50mm lenses don't have significant issues with geometric distortion, and the HD Pentax-D FA* 50mm F1.4 SDM AW is no different"
- ePHotozine/Imatest: 0.01%

Is this a property of macro lens designs, or 50mm lens designs, to produce zero optical distorsion?
Are there any other lenses around that produce zero distorsion around 100mm focal length?


Last edited by biz-engineer; 02-19-2020 at 02:44 AM.
02-19-2020, 02:26 AM - 1 Like   #2
Veteran Member




Join Date: Apr 2018
Posts: 639
Most primes with focus lengths >=50mm show very low distortion.
02-19-2020, 02:29 AM   #3
Pentaxian




Join Date: Feb 2015
Photos: Gallery
Posts: 12,177
Original Poster
QuoteOriginally posted by WorksAsIntended Quote
Most primes with focus lengths >=50mm show very low distortion.
DA200 prime, DA300 prime, also? I'm going to check that out. I noticed photographers using a 70-200 zoom for capturing panos. However when I tried with my DFA70-200 2.8, I found it difficult to use practically, not only it's a bit large heavy to manipulate, but the parallax error is so much and moving so much that even my 200mm rail isn't long enough to use to cover the full FL range from 70mm to 200mm.

---------- Post added 19-02-20 at 10:47 ----------

DA200 f/2.8: " Imatest only recorded 0.0262% barrel distortion" (ephotozine test).
02-19-2020, 03:20 AM - 4 Likes   #4
Veteran Member
kh1234567890's Avatar

Join Date: Sep 2010
Location: Manchester, UK
Photos: Gallery
Posts: 2,653
QuoteOriginally posted by biz-engineer Quote
Along with parallax errors, non-ideal lens distorsion is a pain for stitching images since not all distorsion follow a nice a,b,c distorsion correction model, resulting in some mismatch between frames.
With decent stitching software I do not worry about lens distortion or parallax. I shoot my panos handheld with whatever lens I happen to have on the camera at the time







02-19-2020, 04:00 AM   #5
Moderator
Site Supporter
Loyal Site Supporter
Sandy Hancock's Avatar

Join Date: Feb 2012
Location: Adelaide Hills, South Australia
Photos: Gallery | Albums
Posts: 11,254
QuoteOriginally posted by kh1234567890 Quote
With decent stitching software I do not worry about lens distortion or parallax. I shoot my panos handheld with whatever lens I happen to have on the camera at the time


Sydney by kh1234567890
Hey, that's my daughter's ship! I've done three cruises on the Ovation in the last three years

And yeah, any half decent mid-telephoto stitches pretty well. That said, some of my best have come from the FA31 and DA*55.
02-19-2020, 04:53 AM   #6
Pentaxian




Join Date: Feb 2015
Photos: Gallery
Posts: 12,177
Original Poster
QuoteOriginally posted by kh1234567890 Quote
With decent stitching software I do not worry about lens distortion or parallax. I shoot my panos handheld with whatever lens I happen to have on the camera at the time
I agree. Having done horizontal panoramas in the past with the K200D of some distant scenery, and it worked pretty well. But the recent experiments I've done including proximity foreground with an equivalent FoV of 20mm showed difficult to stitch (with some small discontinuities), I had lens distorsion correct set to "off". After correcting for lens distorsion, the discontinuities improved but were still present. I remember having stitched images from the 100 macro on the K3 and I didn't have this problem, it happens that the 100 macro has no distorsion, but I don't have it anymore since I sold it to buy a Samyang 85 1.4 (mistake, I should have kept the 100 macro). Having sold the 100 macro was a mistake, I lost the macro and portrait capability, and now realize I lost the panorama capability as well what have I done
02-19-2020, 07:42 AM   #7
Veteran Member
Kobayashi.K's Avatar

Join Date: Mar 2013
Photos: Albums
Posts: 716
When distortion gives problems in a stitcher you can always correct the individual photos in an editor before feeding them to the stitcher. Both barrel distortion and perspective distortion can easily be corrected beforehand, you can even resize them to the same scale.

02-19-2020, 07:56 AM   #8
Veteran Member




Join Date: Jul 2009
Location: Tromsø, Norway
Photos: Albums
Posts: 1,031
Note that distortion are measured as % of the image frame. If you choos longer focal lengths, and thus needs more photos to cover the scene, you will get less distortion in the final scene, even if the distortion per frame are the same.

Ideally you would choose the longest focal length lens you want to carry and stitch lots of images to fill the scene. Its heavy and lots of work, so limit the ambitions to something more managable.
02-19-2020, 08:12 AM   #9
Loyal Site Supporter
Loyal Site Supporter
MossyRocks's Avatar

Join Date: Nov 2017
Location: Minnesota
Photos: Gallery | Albums
Posts: 2,978
I would look at the stitching software one is using if you get errors. I've found photoshop and lightroom to be about the worst for stitching but will often produce reasonable results. I consistently get better results with MS Image Composite Editor or Hugin even when doing dumb things like stitching images shot with my S-M-C 17mm fisheye Takumar so I can create a little world/planet picture. I find the same with aligning images for various stacking projects. If Hugin or MS ICE get confused by some image in a panorama or stack then Photoshop will just mess the bed with it and try to make a rectangle into a triangle.

When shooting panoramas I've found the biggest killer is parallax which results in odd stitches. If you can't avoid it (I need a nice gimbal head now I think) the only solutions I have for that is lots of overlap between shots and/or manual corrections after stitching.
02-19-2020, 08:57 AM   #10
Pentaxian




Join Date: Feb 2015
Photos: Gallery
Posts: 12,177
Original Poster
QuoteOriginally posted by Kobayashi.K Quote
Both barrel distortion and perspective distortion can easily be corrected beforehand
That's a good thing, pre-corrected images helps the stitching software to only have to deal with perspective distorsion.

QuoteOriginally posted by Simen1 Quote
Note that distortion are measured as % of the image frame. If you choos longer focal lengths, and thus needs more photos to cover the scene
Ah that's good to point that out. In the meantime, I just realized that increasing the number of tiles is lot better for stitching. As I've stitched only a few frames from the Pentax K1, as the FoV gets wider there is more "stretching" of the image plane once projected on a sphere. The more of smaller tiles we use the less stretching there is, because the distance between tile corners and the spherical model is reduced. So I believe using a crop camera and taking more exposures to cover the same total frame would actually make the image stitching better.

---------- Post added 19-02-20 at 16:59 ----------

QuoteOriginally posted by MossyRocks Quote
I consistently get better results with MS Image Composite Editor or Hugin
I used both. ICE is more automated by give less control. I use hugin. The "create control points" automation is not that smart because lots of points aren't necessarily onto image details that are known to be fixed, selecting fewer control points manually works better (but time consuming).
02-19-2020, 09:15 AM   #11
Loyal Site Supporter
Loyal Site Supporter
MossyRocks's Avatar

Join Date: Nov 2017
Location: Minnesota
Photos: Gallery | Albums
Posts: 2,978
QuoteOriginally posted by biz-engineer Quote
I use hugin. The "create control points" automation is not that smart because lots of points aren't necessarily onto image details that are known to be fixed, selecting fewer control points manually works better (but time consuming).
I've found that using the default control point algorithm is probably one of the worst for panoramas, especially if dealing with images that have high and low detail areas. I like the multi-row panorama option better as I have had really good success using it for creating shots like this one of the moon at 2000mm and there you have the surface of the moon with lots of detail and then the nothingness black that is the sky. There is also the option for using the align_image_stack program in hugin for creating and working with control points and there are a lot of knobs there to play with. I mostly have used that for stacking images and not panos but it is an option.
02-19-2020, 09:34 AM   #12
Veteran Member
kh1234567890's Avatar

Join Date: Sep 2010
Location: Manchester, UK
Photos: Gallery
Posts: 2,653
QuoteOriginally posted by MossyRocks Quote
When shooting panoramas I've found the biggest killer is parallax which results in odd stitches. If you can't avoid it (I need a nice gimbal head now I think) the only solutions I have for that is lots of overlap between shots and/or manual corrections after stitching.
The biggest killer are overhead power lines against a clear sky. They never stitch well.
02-19-2020, 10:20 AM   #13
Pentaxian




Join Date: Feb 2015
Photos: Gallery
Posts: 12,177
Original Poster
QuoteOriginally posted by kh1234567890 Quote
The biggest killer are overhead power lines against a clear sky. They never stitch well.
Power lines can be replaced by blue sky using a clone tool . That's cheating, but once done nobody can tell.
02-19-2020, 11:18 AM   #14
Veteran Member
Kobayashi.K's Avatar

Join Date: Mar 2013
Photos: Albums
Posts: 716
QuoteOriginally posted by biz-engineer Quote
Power lines can be replaced by blue sky using a clone tool . That's cheating, but once done nobody can tell.
That's not cheating. You can clean up an image until the result conforms to the idea of an end-result you have in mind.

So, if power lines or other features are interfering with stitching simply remove them or make other corrections. What's the problem with that?

If I switch off the distortion correction for a quality lens like the Pentax DA 21 Limited you can see how huge it's inherent barrel distortion is. So, is Ricoh cheating on this lens?
02-19-2020, 12:27 PM   #15
Pentaxian
Thagomizer's Avatar

Join Date: Jun 2014
Location: London Ontario
Posts: 2,068
I've not used mine for pano stitching, but the Sigma 70mm EX DG Macro might work well:

https://www.pentaxforums.com/userreviews/sigma-70mm-f2-8-ex-dg-macro.html

Sigma AF 70mm f/2.8 EX DG macro - Full Format Lab Test / Review - Analysis

Sigma 70mm f/2.8 EX DG Macro Interchangeable Lens Review | ePHOTOzine

Sigma 70mm f/2.8 EX DG Macro Review
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!
200mm, 50mm, 70mm, barrel distortion, control, da200, designs, distorsion, distortion, f/2.8, frame, image, images, k-mount, lens, lenses, macro, model, pentax, pentax lens, perspective, perspective distortion, pf, slr lens, stitching, tiles
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Stitching a panorama on the cheap? Lhorn Digital Processing, Software, and Printing 25 12-04-2019 12:50 PM
Kolor has closed - AutoPano Panorama Stitching Software no longer available. interested_observer Digital Processing, Software, and Printing 5 11-02-2018 12:42 PM
Need advice on iPhone camera app with manual settings and panorama stitching app. Emacs Canon, Nikon, Sony, and Other Camera Brands 2 10-18-2018 12:49 PM
Landscape First attempt at stitching a panorama PancakeFlipper Post Your Photos! 9 07-10-2018 05:07 AM
Brenizer Method or Panorama Stitching trevorgrout Photographic Technique 7 09-02-2013 05:52 AM



All times are GMT -7. The time now is 05:47 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