Perspective Correction??

[ScoutR]

Hi everyone: I'd really like some C&C on how to fix perspective in photos like this taken with a wide angle lens. I realize that this is normal with wide angle shots, but I know some of you kids can work magic in PP on this type of thing. Personally, I'm looking for how to correct in Elements 8, but open to how to in any program, if it might help others out too.

Thanks
Wendy


Nikon D3000: 18-200mm: 1/50s: f13: ISO 400: 18mm

[Peter Ryan]

Hi Wendy,

I have not used Elements but in PS there under Filters/Distort/Lens Correction you can fix most of this. Very intuitive. Let me know if you have this in Elements and I can answer other questions you might have.

[Dave Humphries]

Hi Wendy,

In Elements 8, I use Image > Transform > Distort to correct these off centre and leaning shots.

Here's yours, showing the corners and sides dragged out to eliminate everything except the barrel distortion. I wouldn't normally need to touch the bottom or sides, but you had black border on, which I got rid of for the purposes of the demo.



The barrel should be correctable in the Filter > Correct Camera Distortion, except it is greyed out.
It's not a problem I've needed to correct before, at least not in living memory, so I'm a bit stumped

Hope this much is helpful anyway,

[ScoutR]

Thanks Peter & Dave: I have been using Image > Transform > Perspective without much luck. I will try Image > Transform > Distort and see how that goes. Looks much better Dave. Ummmm, what is the barrel distortion you refer to? Also Correct Camera Distortion might be greyed out because I did some (unsuccessful) perspective editing on this already???? not sure

Thanks guys
Wendy

[Dave Humphries]

Thanks Peter & Dave: I have been using Image > Transform > Perspective without much luck. I will try Image > Transform > Distort and see how that goes. Looks much better Dave. Ummmm, what is the barrel distortion you refer to? Also Correct Camera Distortion might be greyed out because I did some (unsuccessful) perspective editing on this already???? not sure

Thanks guys
Wendy

Hi Wendy,

The barrel distortion is what is causing the top of the building to be nearer the edge of frame in centre of picture than at the corners, there is a similar effect seen on the road markings along the bottom edge.

It seems it is the monochrome conversion prevents the Correct Camera Distortion filter from working, I guess because it knows it is no longer a camera image.

The answer would appear to be for you to do the mono conversion after the distortion (first) and (then) the barrel correction, by moving the top slider to the right a bit.



EDIT: In fact looking at the above, you could possibly do it all here using the independent Horizontal and Vertical perspective controls as well, although because you weren't quite straight on, it might not be quite as accurate as the independently draggable corners available in the Image > Transform > Distort.

Cheers,

[McQ]

In Photoshop CS, the Filter > Lens Correction tool is greay -- especially if you use the grid overlay (by pressing "v" while on that screen). This file didn't have any EXIF remaining in it, but if it did the program can auto-correct the barrel distortion based on the zoom setting and lens model. Here's what it looks like without the barrel distortion



PS Settings were . . . Distortion: +18, Vertical: -40, Horizontal: +7

The barrel should be correctable in the Filter > Correct Camera Distortion, except it is greyed out.
It's not a problem I've needed to correct before, at least not in living memory, so I'm a bit stumped

There was an error message I got when I loaded the image (relating to the embedded color profile). That may have been the reason, but it could also be due to the monochrome file, or is just because that filter didn't see any EXIF data. It should still let you load it and apply manually.

Wendy: something else you might want to try is the PTLens add-on plugin for photoshop. That might make sense for PSE. It has a 10 image trial, but otherwise costs $25. Not too bad considering how much use it will get. Anyways, just a thought. On the other hand, ideally one would perform all these corrections during the RAW conversion (using Adobe Camera RAW, Lightroom, the camera's software, etc -- many of these have lens distortion tools as well).

[carregwen]

Wendy

Like Sean, I use CS5 lens correction with the grid overlay, and it is excellent. It always does a much better job that I think it will. I'm not sure what is available for this feature in pre-CS5 though. I used it this afternoon to do a shot for the BW comp. Here is the original RAW and the finished lens-corrected shot. I used the G1 camera and I was very close to the building (obstruction behind me), and not quite in the centre. The correction tilted the top of the shot towards me, and I also adjusted the slope in the vertical lines at the side of the gateway.

[ScoutR]

You guys are amazing. Dave, I've never tried that camera correction function. Below are the results. I will have to practice, this one is still a little skewy (to the left) but I think it is certainly better than the first. I have trouble putting a label on staight so this is difficult for me.

Thanks also for the barrel distortion definiton - something else for me to watch for, and now be able to correct. All this time I've been fooling around with all the Image > Transform > Perspective and getting nowhere. I didn't even think it would be possible with Elements to correct this type of shot by bringing the top forward as Rob described for his Pier shot.

I'm not sure what is happening with the EXIF and/or why the Camera Correction is greyed out when you try to edit, but I've taken this one back through various stages and Camera Correction in Elements is available to me at every stage DNG, PSD before and after editing and jpg.

Thanks again everyone. Every post has had very helpful information, and now I have a lot of shots that can be corrected.

[arith]

Cor that was a challenge; don't listen to them, just get yourself Helicon Filter, I always save to 16 bit tiff in photoship and open in Helicon to do the distortion and cloning thingies.



You got big cars in Canada.

[Dave Humphries]

In Photoshop CS, the Filter > Lens Correction tool is greay -- especially if you use the grid overlay (by pressing "v" while on that screen). This file didn't have any EXIF remaining in it, but if it did the program can auto-correct the barrel distortion based on the zoom setting and lens model. Here's what it looks like without the barrel distortion



PS Settings were . . . Distortion: +18, Vertical: -40, Horizontal: +7

There was an error message I got when I loaded the image (relating to the embedded color profile). That may have been the reason, but it could also be due to the monochrome file, or is just because that filter didn't see any EXIF data. It should still let you load it and apply manually.

Wendy: something else you might want to try is the PTLens add-on plugin for photoshop. That might make sense for PSE. It has a 10 image trial, but otherwise costs $25. Not too bad considering how much use it will get. Anyways, just a thought. On the other hand, ideally one would perform all these corrections during the RAW conversion (using Adobe Camera RAW, Lightroom, the camera's software, etc -- many of these have lens distortion tools as well).

Ah yes, I'd forgotten about the error message, I got that too, and on one of Wendy's other monochrome's, which also would not allow use of the camera distortion feature.

Using the grid makes it much more accurate at getting things straight all over, I did mine by eye and although I got both sides right, I still have a small lean up the midddle. Thanks Sean.

Wendy,

As you have LR (as well as Elements), you should, I think, be able to use the camera tab in ACR to fix these things.

Cheers,

[arith]

I definitely think you are going ups ze hill, or buildings are wonki in Canada; cor definitely a challenge.





It helps to know what it looked like

[McQ]

I definitely think you are going ups ze hill, or buildings are wonki in Canada; cor definitely a challenge.
It helps to know what it looked like

Haha -- yes, that would really help to know whether the car was driving up a hill or not! . In my version it was clear I had assumed level ground, which really changes everything...

[ScoutR]

Ah yes, I'd forgotten about the error message, I got that too, and on one of Wendy's other monochrome's, which also would not allow use of the camera distortion feature.

Hmmm, very strange - did you make sure it was in 8 bit. I know I know of course it should have been, but I noticed when I loaded the jpg back into Elements, that Camera Correction was greyed out and I had to change it to 8 bit, which doesn't make sense to me, because I had to convert it to 8 bit to save it as a jpg in the first place. If it's not that I don't know where it is happening.

Wendy,

As you have LR (as well as Elements), you should, I think, be able to use the camera tab in ACR to fix these things.

Yes, I was hoping I would be able to do this in Lightroom, but it appears all I can do is Straighten. From what I've read I think I would have to upgrade to version 3 and even then I'm not sure if the camera correction is there. I'm very happy with what I now know can be done with Elements, so I will start to open anything that needs perspective or lens correction in ACR first instead of going right to the Editor from Lightroom.

Thanks again Dave, very helpful as always
Wendy

[ScoutR]

I definitely think you are going ups ze hill, or buildings are wonki in Canada; cor definitely a challenge.





It helps to know what it looked like

That looks pretty good Arith. You guys have done a great job. I on the other hand need lots of practice. By the way, it should be level. The buildings are not wonki but some photographers are. . I find I have to rotate a lot of my shots counterclockwise. I'm especially bad on this type of shot, because I'm trying to get it to look straight in the camera and if I get verticals straight horizontals are off and so on and so on, but bottom line is that I have trouble seeing straight.

Thanks again everyone - this was very very helpful. I really did not think I could correct this problem without getting a different lens.

Wendy

[Sonic4Spuds]

You guys are amazing. Dave, I've never tried that camera correction function. Below are the results. I will have to practice, this one is still a little skewy (to the left) but I think it is certainly better than the first. I have trouble putting a label on staight so this is difficult for me.

There should be a skiew correction function in Photoshop even elements (if not I have found something that GIMP has which Photoshop doesn't , please don't start that old argument again I don't care what people use). If alright with you I would like to use this image in a 4-H workshop I am planning on teaching on photo editing.