Correcting lens distortion

"Chrisssssss………" wrote in message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?
Many thanks, Chrissss………

Depending on the quality of your camera and the quality you wish for the final image!! you could try taking the picture from farther away and then cropping and expanding the resultant image, I would think it would help to use the longest lens you have! Obviously you would need to have the documents in a vertical position! or on the floor at the bottom of a stair well!

The effect you describe is called "barrel distortion" and is common when photographing objects with a wide angle lens. You can correct it in Photoshop under Filters / Distort / Spherize… and apply a negative value, but I don’t know whether this is available in Elements.

Hope this helps

John

"Chrisssssss………" wrote in message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?
Many thanks, Chrissss………

"Chrisssssss………" wrote in
message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?
Many thanks, Chrissss………

Thanks John, but I’ve just tried using Spherize but find it doesn’t give me enough control. I have heard that Elements somewhere alows you to ‘pull’ a corner or edge in or out. But I can’t find where this is. Any ideas. Thanks Chrisssss……….

"Chrisssssss………" wrote in message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?

Your camera lens may have a zoom setting that eliminates or minimizes this distortion. Try moving farther away and setting the zoom to the middle of its range.
—
Mike Russell
www.curvemeister.com

"Mike Russell" wrote in message

"Chrisssssss………" wrote in
message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?

Your camera lens may have a zoom setting that eliminates or minimizes this distortion. Try moving farther away and setting the zoom to the middle of its range.
—
Mike Russell
www.curvemeister.com

Thanks Mike. I’ll try what you suggest. Sounds like a good idea. Appreciated. Chrisssss…….

But I still feel that Elements has a setting somewhere that WILL let me do what I want. I’ve looked at "3-D transform" and the help files on ‘Perspective’ but I still haven’t managed to work out how to do it. It’s so frustrating, because I KNOW that Elements CAN do this.
Surely someone must have done this sucessfully?
Chrissssssss……….

DCE Tools have a plug-in that fixes lens distortion.

"Chrisssssss………" wrote in message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?
Many thanks, Chrissss………

DCE Tools have a plug-in that fixes lens distortion.

"Chrisssssss………" wrote in
message

Thanks. Can you tell me how to obtain the above tool. I’ve looked at Elements 2/Help/Plug ins, but there isnt one listed to tackle lens distortion.

Chrissssss……..

On Sun, 6 Nov 2005 15:42:11 -0000, "Chrisssssss………" wrote:

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?
Many thanks, Chrissss………

I can’t see how the transform tools will do the job – they tend to move things in straight lines.

I have used the software fron Humansoftware at

http://www.humansoftware.com/index.shtml

They have a lot of stuff including barrel distortion correction – looks a bit expensive.

Chrisssssss……… wrote:

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?
Many thanks, Chrissss.

Chrissss,

I don’t know if Photoshop Plug-Ins work with Elements, but if they do, here’s a link to a free lens distortion correction filter. There are a number of other filters on this page which cost $$, but scroll down the page, and the free ones are near the bottom.

Photoshop Plugins
http://www.richardrosenman.com/photoshop.htm

Hope this works in Elements. I use it from PS7, and it’s simple and effective.

Mike

I don’t know if Photoshop Plug-Ins work with Elements, but if they do, here’s a link to a free lens distortion correction filter. There are a number of other filters on this page which cost $$, but scroll down the page, and the free ones are near the bottom.

Photoshop Plugins
http://www.richardrosenman.com/photoshop.htm

Hope this works in Elements. I use it from PS7, and it’s simple and effective.

Mike

A thousand thank you’s Mike & Avery. The plug-in link Mike supplied works a treat in Elements 2 and is free. Very easy to use as you say. Much appreciated. Chrisssssss………

On Sun, 6 Nov 2005 19:36:10 -0000, "Chrisssssss………" found these unused words floating about:

"Mike Russell" wrote in message

"Chrisssssss………" wrote in
message

Can anyone advise me: I wish to photograph many old documents, most of which are A4 size. But my camera distorts the rectangular pages by ‘ballooning’ them (a slight fish-eye effect). Is there a simply method using Elements 2 to correct this?

Your camera lens may have a zoom setting that eliminates or minimizes this distortion. Try moving farther away and setting the zoom to the middle of its range.
—
Mike Russell
www.curvemeister.com

Thanks Mike. I’ll try what you suggest. Sounds like a good idea. Appreciated. Chrisssss…….

ANY camera lens set ‘less’ (wide angle) than ‘normal’ (35mm format = 55mm) will have distortion.

For document copying 80mm (or equivalent) will produce proper aspect and (unless the lens is of poor quality) straight edges.

You don’t need to be either clipped on the wall or on the floor or ‘at the bottom of a stairwell’, you DO need to have the camera centered and square to the image you are copying. Even lighting is also a must.

DRAW a grid of (say) 1" spaced lines on a paper that’s slightly larger than the item(s) you are copying. Position the camera and take images, making adjustments, until the grid is ‘perfect’. Then laying the document on the grid will also help align it to be ‘level’ and ‘square’ to the camera!

HTH

"J. A. Mc." wrote in message

ANY camera lens set ‘less’ (wide angle) than ‘normal’ (35mm format = 55mm) will have distortion.

Huh?

To make a blanket statement that any camera lens set to less than "normal" will have distortion isn’t really true. There are perspective issues with ANY camera lens, even normal lenses and telephotos if you tilt them with respect to the subject.

Sure, every lens made has some distortion and if you have precise enough equipment you can measure distortions in even the finest lenses down to a few hundredths of a percent, but that wouldn’t normally be perceptible in a photograph. You have to distinguish between perspective distortion (usually called "keystoning") and optical distortions produced by the lens. There are lenses made (in the professional price range) with distortions less than a few tenths of a percent, but most of us can’t afford them.

Norm

On Wed, 09 Nov 2005 23:00:18 GMT, "Norm Dresner" found these unused words floating about:

"J. A. Mc." wrote in message

ANY camera lens set ‘less’ (wide angle) than ‘normal’ (35mm format = 55mm) will have distortion.

Huh?

To make a blanket statement that any camera lens set to less than "normal" will have distortion isn’t really true. There are perspective issues with ANY camera lens, even normal lenses and telephotos if you tilt them with respect to the subject.

Yes, it’s quite true! There isn’t ANY lens that doesn’t exhibit some distortion (curvature of field) when set/made under the ‘normal’ lans for the format.

This is TRUE, whether the camera is perfectly squared to its subject or not, perspective issues only ADD to the distortion!

Curvature of field is NOT a perspective issue, BTW. Very separate physics involved.

Sure, every lens made has some distortion and if you have precise enough equipment you can measure distortions in even the finest lenses down to a few hundredths of a percent, but that wouldn’t normally be perceptible in a photograph.

BFS! Guess you haven’t used lenses (prime of zoom) under 30mm on a 35mm camera before?

You have to distinguish between perspective distortion (usually called "keystoning") and optical distortions produced by the lens. There are lenses made (in the professional price range) with distortions less than a few tenths of a percent, but most of us can’t afford them.

Perhaps if you hadn’t snipped the original poster to bash my reply, you’d have noted that he was commenting on ‘correcting the lens’ through a plug-in. This is USUALLY taken to mean the curvature (OPTICAL) effect of a wide angle setting.

"J. A. Mc." wrote in message

On Wed, 09 Nov 2005 23:00:18 GMT, "Norm Dresner" found these
unused words floating about:

"J. A. Mc." wrote in message

ANY camera lens set ‘less’ (wide angle) than ‘normal’ (35mm format = 55mm)
will have distortion.

Huh?

To make a blanket statement that any camera lens set to less than "normal" will have distortion isn’t really true. There are perspective issues with ANY camera lens, even normal lenses and telephotos if you tilt them with respect to the subject.

Yes, it’s quite true! There isn’t ANY lens that doesn’t exhibit some distortion (curvature of field) when set/made under the ‘normal’ lans for the format.

This is TRUE, whether the camera is perfectly squared to its subject or not,
perspective issues only ADD to the distortion!

Curvature of field is NOT a perspective issue, BTW. Very separate physics involved.

Sure, every lens made has some distortion and if you have precise enough equipment you can measure distortions in even the finest lenses down to a few hundredths of a percent, but that wouldn’t normally be perceptible in a
photograph.

BFS! Guess you haven’t used lenses (prime of zoom) under 30mm on a 35mm camera before?

In your enthusiasm to disparage my comments, you’ve confused perspective distortion with optical distortion. There are (very expensive) lenses — even wide angle ones — that have very low distortion. I never implied that all lenses had that characteristic.

Norm

On Thu, 10 Nov 2005 14:11:48 GMT, "Norm Dresner" found these unused words floating about:

"J. A. Mc." wrote in message

On Wed, 09 Nov 2005 23:00:18 GMT, "Norm Dresner" found these
unused words floating about:

"J. A. Mc." wrote in message

ANY camera lens set ‘less’ (wide angle) than ‘normal’ (35mm format = 55mm)
will have distortion.

Huh?

To make a blanket statement that any camera lens set to less than "normal" will have distortion isn’t really true. There are perspective issues with ANY camera lens, even normal lenses and telephotos if you tilt them with respect to the subject.

Yes, it’s quite true! There isn’t ANY lens that doesn’t exhibit some distortion (curvature of field) when set/made under the ‘normal’ lans for the format.

This is TRUE, whether the camera is perfectly squared to its subject or not,
perspective issues only ADD to the distortion!

Curvature of field is NOT a perspective issue, BTW. Very separate physics involved.

Sure, every lens made has some distortion and if you have precise enough equipment you can measure distortions in even the finest lenses down to a few hundredths of a percent, but that wouldn’t normally be perceptible in a
photograph.

BFS! Guess you haven’t used lenses (prime of zoom) under 30mm on a 35mm camera before?

In your enthusiasm to disparage my comments, you’ve confused perspective distortion with optical distortion. There are (very expensive) lenses — even wide angle ones — that have very low distortion. I never implied that all lenses had that characteristic.

Norm

No, I haven’t!

The OP was talking OPTICAL .. YOU brought in perspective as a bash to my reply!

Do re-read the OP!

"Very low", still is not what you want when copying a document!

Kirk Splaat.