I am still trying out a 30mm lens which gives me a crop factor of about a 45mm lens.  Sure, distortion from the smaller focal length is still there but how apparent is it?

I post these two images for your comparison. Since I use not in-camera sharpening, slight sharpening is applied but that is all besides crop and resize for web.  

Please take a look and see if there is really apparent difference enough to scrap the lens and try something else.  You see, one image is corrected for "barrel distortion", the aberration that makes straight lines go curved upward from the center, like looking at the side of a barrel.

This is how the correction was made and is not scientific or purist:  I took shots of a brick wall. The wall has fairly stright rows of bricks.  Then, curves at the top and bottom were supposed to be apparent or more apparent depending on the lens used.  The brick wall test showed a slight curve or barrel distortion at the closest focal point of the lens.  I corrrected that and applied the same setting to one of the bridge shots show here.

Do you see a significant difference?  Without comparison would you think one photo distorted? That is after the fact, oops, since both photos are here!

Any thoughts will be appreciated.               TomDArt.

Here is the other one. Thanks for viewing and any comments.

Now, I have to view the bridge again..to see how it really looks in comparison.

Honestly....can't see much if any difference between the two photos.  Perhaps a test (in portrait orientation) of something with long vertical lines...to better display any distortion.

You do have some serious dust bunnies on your sensor though.....

In youth, we learn....with age, we understand.

gradient, I have taken care of the dust bunnies in the cam...all happened apparently when putting on the lens. I saw that but did not want to correct these images any more for posting.

The distortion was slightly apparent in the  first test (brick wall) but not in shots like this.  As far as I am concerned, if good enough not to notice it is not serious and is simply not noticed. Does that make sense?  Thoughts like yours are the very reason I posted the shots...even with the dust bunnies! Yikes.              Thanks.       TomDart.

Yes, makes sense....for shots like this, it's not noticable.  That's why I think a better test would be with shots showing long vertical lines especially at the image edges...ie architectural type shots.  I think any distortion would be most noticable then.

Re: dust bunnies....LOL!!!  If you have followed any of my threads....you will know I hate dust bunnies!...Double LOL!!!

In youth, we learn....with age, we understand.

Gradient, now I see what you mean.   I will try some shots with vertical lines and see if distortion is something of merit or to be dismissed.  We will see tomorrow after the sun rises.  thanks.

 

 

Tom

 

I don’t think that in this type of image barrel distortion will be that apparent if at all, like Gradient said strong horizontals and verticals will emphasize it, especially at frame edges where the frame is straight and barrel distortion is more visible.

 

Landscapes will show it less than most subjects, as there are seldom defined lines.

 

Don’t forget, that close work done with a wide lens will make it look more visable.

 

One last thing I would mention, barrel distortion is sometimes mistaken in vast wide scenes (say looking out to sea) where the horizon can be several miles wide on the frame, where you actually see the curvature of the earth as opposed to distortion.

 

Dust Bunnies! lol never heard that expression before!

Enola

Full Time Professional Photographer