Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Computing > Digital Photography > Camera correcting lens distortions?

Reply
Thread Tools

Camera correcting lens distortions?

 
 
Matthias Heiler
Guest
Posts: n/a
 
      07-06-2004
Hi group,

Is there a camera that electronically corrects geometrical lens
distortions (esp. Barrel)? For the fixed-lens digital cameras out
there this should be not hard to implement. It also would
manufacturers allow to use cheaper/lighter glass on their consumer
products and still get decent image quality.

On a similar note, does anybody know a decent lens-distortion
correction software for Linux? It should be able to work on many
images automatically, without manual intervention.

Thanks,

Matthias
 
Reply With Quote
 
 
 
 
Hans-Georg Michna
Guest
Posts: n/a
 
      07-06-2004
On 06 Jul 2004 11:50:08 +0200, Matthias Heiler <(E-Mail Removed)>
wrote:

>Is there a camera that electronically corrects geometrical lens
>distortions (esp. Barrel)? For the fixed-lens digital cameras out
>there this should be not hard to implement. It also would
>manufacturers allow to use cheaper/lighter glass on their consumer
>products and still get decent image quality.


Matthias,

I don't have an answer to your question. Only wanted to remark
that any recalculation that involves pixel relocation will
necessarily reduce sharpness. I guess that this is one of the
reasons why nobody may be doing it in the camera.

There's most likely some software though.

Hans-Georg

--
No mail, please.
 
Reply With Quote
 
 
 
 
Mxsmanic
Guest
Posts: n/a
 
      07-06-2004
Matthias Heiler writes:

> Is there a camera that electronically corrects geometrical lens
> distortions (esp. Barrel)?


No. It's very difficult because distortions vary with the lens, the
focal length setting (for zooms), the aperture setting, and even the
current focus setting. A camera would have to have all this information
internally recorded for all lenses in order to correct anything.
Additionally, some types of lens defects cannot be corrected after the
fact (such as blurriness).

> It also would
> manufacturers allow to use cheaper/lighter glass on their consumer
> products and still get decent image quality.


They are already using very cheap glass in most cases.

--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly.
 
Reply With Quote
 
Ray Paseur
Guest
Posts: n/a
 
      07-06-2004
I am certain that a software product exists for correcting Barrel distortion
in wide-angle lenses. Sorry I cannot tell you its name! Perhaps Google can
remember better than I can. It may be a Photoshop plug-in. ~Ray
"Matthias Heiler" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)-mannheim.de...
> Hi group,
>
> Is there a camera that electronically corrects geometrical lens
> distortions (esp. Barrel)? For the fixed-lens digital cameras out
> there this should be not hard to implement. It also would
> manufacturers allow to use cheaper/lighter glass on their consumer
> products and still get decent image quality.
>
> On a similar note, does anybody know a decent lens-distortion
> correction software for Linux? It should be able to work on many
> images automatically, without manual intervention.
>
> Thanks,
>
> Matthias



 
Reply With Quote
 
Robert Feinman
Guest
Posts: n/a
 
      07-06-2004
In article <(E-Mail Removed)-mannheim.de>,
http://www.velocityreviews.com/forums/(E-Mail Removed) says...
> Hi group,
>
> Is there a camera that electronically corrects geometrical lens
> distortions (esp. Barrel)? For the fixed-lens digital cameras out
> there this should be not hard to implement. It also would
> manufacturers allow to use cheaper/lighter glass on their consumer
> products and still get decent image quality.
>
> On a similar note, does anybody know a decent lens-distortion
> correction software for Linux? It should be able to work on many
> images automatically, without manual intervention.
>
> Thanks,
>
> Matthias
>

Panorama Tools will correct barrel and pincushion distortion. It is
a plugin for photoshop and is free.
Also lookup ptlens.

--
Robert D Feinman
Landscapes, Cityscapes and Panoramic Photographs
http://robertdfeinman.com
mail: (E-Mail Removed)
 
Reply With Quote
 
David J Taylor
Guest
Posts: n/a
 
      07-06-2004
"Ray Paseur" <(E-Mail Removed)> wrote in message
news:40ea92bb$0$3085$(E-Mail Removed)...
> I am certain that a software product exists for correcting Barrel

distortion
> in wide-angle lenses. Sorry I cannot tell you its name! Perhaps Google

can
> remember better than I can. It may be a Photoshop plug-in. ~Ray


This sort of distortion correction is built into both Paint Shop Pro and
Pano Tools. Of necessity, there is a sharpness reduction. Whether
correction would be better done _before_ the Bayer interpolation or after
is something I would like to know.

It amuses me that so much effort is put into hardware when to do the same
in software is relatively simple coding, and it would not need to be
restricted to fixed-focal length cameras either - a different degree of
correction for each zoom. However, it is a slow process, and the limited
CPU power in digital cameras may be hindering implementation.

Cheers,
David


 
Reply With Quote
 
Gisle Hannemyr
Guest
Posts: n/a
 
      07-06-2004
Matthias Heiler <(E-Mail Removed)> writes:
> Is there a camera that electronically corrects geometrical lens
> distortions (esp. Barrel)?


AFAIK, no.

> On a similar note, does anybody know a decent lens-distortion
> correction software for Linux? It should be able to work on many
> images automatically, without manual intervention.


Helmut Dersch' Panorama Tools is what you want. It is free software,
has been ported to Linux, and is excellent for batch work.

http://home.no.net/dmaurer/~dersch/Index.htm
--
- gisle hannemyr [ gisle{at}hannemyr.no - http://folk.uio.no/gisle/ ]
================================================== ======================
«To live outside the law, you must be honest.» (Bob Dylan)
 
Reply With Quote
 
Matthias Heiler
Guest
Posts: n/a
 
      07-06-2004
"David J Taylor" <(E-Mail Removed)-this-bit.nor-this-part.uk> writes:

> It amuses me that so much effort is put into hardware when to do the same
> in software is relatively simple coding, and it would not need to be
> restricted to fixed-focal length cameras either - a different degree of
> correction for each zoom. However, it is a slow process, and the limited
> CPU power in digital cameras may be hindering implementation.


I'm thinking along the same line. In the best of all worlds cameras
with built-in lens (zoom or prime) would be calibrated by the
manufacturer to correct most distortions automatically. SLRs would
offer a calibration mode where the user takes some images of a
reference object (e.g., a poster provided by the manufacturer) and the
camera measures the distortion of a given lens. Of course, the
correction could be disabled by the user at any time to allow for
maximum sharpness (alternatively one can throw in a couple of extra
megapixels for that).

I understand the CPU argument: Doing the interpolations correctly
would probably require much floating point processing power. But it's
just a matter of time until we have that.

I wonder if any manufacturers are reading this forum...

 
Reply With Quote
 
David J Taylor
Guest
Posts: n/a
 
      07-06-2004
"Matthias Heiler" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)-mannheim.de...
[]
> I'm thinking along the same line. In the best of all worlds cameras
> with built-in lens (zoom or prime) would be calibrated by the
> manufacturer to correct most distortions automatically.


... and external lenses could simply provide the required parameters to the
camera's CPU just like they do for other data today. I don't think
there's a need to restrict this to built-in lenses, is there?

> SLRs would
> offer a calibration mode where the user takes some images of a
> reference object (e.g., a poster provided by the manufacturer) and the
> camera measures the distortion of a given lens. Of course, the
> correction could be disabled by the user at any time to allow for
> maximum sharpness (alternatively one can throw in a couple of extra
> megapixels for that).


Nice one!

> I understand the CPU argument: Doing the interpolations correctly
> would probably require much floating point processing power. But it's
> just a matter of time until we have that.


... and perhaps sooner than we expect!

> I wonder if any manufacturers are reading this forum...


... I should have patented this idea - although I expect someone already
has.

Cheers,
David


 
Reply With Quote
 
John Bean
Guest
Posts: n/a
 
      07-06-2004
On Tue, 06 Jul 2004 12:59:24 GMT, David J Taylor wrote:
> .. and external lenses could simply provide the required parameters to the
> camera's CPU just like they do for other data today. I don't think
> there's a need to restrict this to built-in lenses, is there?


> .. I should have patented this idea - although I expect someone already
> has.


Olympus. 4/3 system has provision to do this, don't know if the E-1
currently does though.

--
John Bean

Electricity is actually made up of extremely tiny particles called
electrons, that you cannot see with the naked eye unless you have been
drinking (Dave Barry)
 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Another question - How to convert medium format lens to equivalencyof a 50mm normal lens (35mm camera) in APS-C digital cameras aniramca@gmail.com Digital Photography 13 05-31-2009 10:02 PM
Correcting an image that has camera shake Dave W Digital Photography 6 01-30-2007 10:03 AM
How to place camera in bag, lens down or lens to side RW Digital Photography 49 12-02-2005 02:51 AM
Reed-Solomon correcting code - coder/decoder in vhdl Wilq VHDL 0 05-17-2004 08:39 AM
Camera technique problem - help correcting Eigenvector Digital Photography 21 08-06-2003 01:00 PM



Advertisments