Just about Photography

Have you ever took  photos with straight line pattern as a background? If you have ever took this kind of photo, you will know that sometimes you get the straight line pattern looked not straight although you have tried to make it as straight as possible. Dealing with this problem (perspective), I think there are many cases, first case is your position and object position isn’t exactly in front of “center of object”. You can see my simple illustration below – T = target, A & B  = photographer locations.

After you see my simple illustration maybe you will get confused because I don’t explain it in detail, so I will give you a sample photo from “Lucky Rainy Day” with straight line pattern (composition) as a background.

Original photo taken with me in A position (see illustration above):

You can see perspective problem of this photo:

I make 4 red lines and also 4 green lines – you can see that horizontal line has problem and vertical line almost perfect (I think haha….). Usually if  both of them (the horizontal lines and vertical lines) are not straight, the problem is “you rotate the camera a little bit” (remember: usually not always).  Because the vertical line almost no problem, so this kind of problem is caused (usually) because your position isn’t in front of center of object.

After you know this problem – you need to think what you need to do in order to make this photo better. For me, I will use Photoshop to correct this problem. This problem can be corrected with simple step – just follow my simple step below.

1. Open your photo.

2. Copy your background layer (ctrl+j).

3. Filter->Distort->Lens Correction. See lens correction dialog box – because in this photo only have horizontal problem so you don’t need to correct vertical perspective. To correct horizontal perspective you just input a number in horizontal perspective – in my case I fill it with 10 – you can try any number until you think horizontal line now is perfect.

4. You will notice that this method can correct perspective problem but some areas in the photo are blank. I fill blank area with red color to make it clearly visible.

5. Most of people will crop this photograph to hide this problem – you can crop it as bigger as possible but it will produce inproportional width/height  or  you crop with proportional width/height (3:2) but you will get smaller image size. Most of time, I like the second choice – I don’t like to crop it inproportional because it will make other people know that “you crop your photo”.  You can see crop version (with proportional width/height = 3:2) below.

Another approach: you can skip step 5 and correct the result after step 4 without crop the photo. You can see the result below – Highlighted green area is missing area because you crop the photo. If you interesting with this approach, make sure you check this blog because I will update this approach in other tutorial. Final version with local contrast, lighting, and color adjustment you can see in “Lucky Rainy Day” album.

I hope after reading this tutorial, you will have some ideas to correct perspective problem. Thanks for reading this tutorial – any comments, suggestions, critiques are welcome.