James A. Rinner: Blog https://jamesarinner.zenfolio.com/blog en-us (C) James A. Rinner (James A. Rinner) Wed, 25 Jan 2017 23:57:00 GMT Wed, 25 Jan 2017 23:57:00 GMT Correcting Ultra-Wide Keystone Effect in Photoshop https://jamesarinner.zenfolio.com/blog/2017/1/correcting-ultra-wide-keystone-effect-in-photoshop Ultra-wide angle lens for the landscape photographers are those heavy pieces of glass that we just can't leave at home.  They can capture dramatic skies like no other lens in your collection.  The problem with them is a distortion called keystoning where the pitch angle (see below) of the camera causes vertical objects to lean toward the center of the image.

Below is a typical example of keystoning that plagues me when using an ultra-wide lens.  The lens is a Panasonic 7-14mm (this is the same as a 14-28mm in 35mm full frame sensors) zoom lens used on an Olympus OM-D. 

Various Methods to Correct or Hide Keystoning

The methods we are going to explore are the following:

  • Clone Stamp and Healing Brush
  • Lens Correction Filter
  • Photo Merge

Clone Stamp and Healing Brush

One approach to removing the keystoning distraction is to use a combination of Clone and Healing brushes in Photoshop. Basically, we will be removing and converging objects from the image. Most of the time the healing brush works well but it may smear a section, or give you results that look obviously manipulated. A mixture of clone and healing brushes will usually give you pleasing results. The most obvious keystoning distractions in this photo are the towers and power lines; as can be seen in the image below.

The healing brush is a good option for the thin power lines. A good way to use the healing brush is zooming in to the pixel level (see below).  This takes much longer but does work well.

Below you will see how I removed the large tower with the healing brush but the results were a bit splotchy.

We still have a few artifacts left so just hit it with the healing brush again in those areas. For this image the results were very good.

 (see below)

Below is the final image using only the clone and healing brush.  This works pretty well but the image (trees and some clouds) still has that keystone look.

What do you do if there are more obvious vertical objects in the scene that you don't want, or can't remove?

Using the Lens Correction Filter

This is a very quick way to fix perspective in an image.  Do not use the automatic lens correction filter but the one accessed by pressing Shift+Control+R (in Windows version). As shown in the image below; go the "Custom" tab and slide the vertical perspective slider to the left (minus) direction till your vertical objects are once again vertical.  Since I am shooting with an ultra-wide zoom even moving the slider all the way to the left (-100) my vertical objects are still keystoning.  Click OK and return to the main Photoshop screen.  I like to use layers so I can see my progress and also go back to various steps if I need to tweak something.

Copy the layer and make your final vertical perspective correction (see below) and click OK for the corrected image.  I could then remove the power lines if I wanted to but many times I will leave them.

See the final image below and you will see that the image no longer has the keystone affect but you can see that I lost some of the image on the side.  How do we keep most of the image that was originally shot and lose the keystone affect? To do this we are going to use the Photo Merge tool.

Photo Merge

This next process has to be preplanned at the time of exposure.  Because I am an old school photographer I shoot about 95% of my landscape work in manual mode, which is essential for this process.  I will now take two separate images and merge them together.  If I was to shoot these images in an automatic exposure mode on my camera, the two images could have different exposures, which would be very obvious in the merging and could cause some extra work trying to balance the images.

I take one photo (the one I used in the previous example) showing all the sky that I want to include.  The next image is taken with the horizon in the center of the frame.  Because my camera is no longed tilted the keystone effect is eliminated.

Below you can see the two images I want to use in Adobe Bridge.

Having selecting both images in Bridge I open them up in Adobe Camera Raw (you can open up jpegs in Adobe Camera Raw) and at this time I am only going to remove chromatic aberration and perhaps a little sharpening.  It is important that whatever you do in one you do the same in the other so select the "Select All" button in the upper left corner.  Save these files.  You can also skip this step and go straight to the next step and work on tweaking the final image later.

Go back to Photoshop and choose: Automate - Photomerge (see below)

Browse for your files, select Auto (default), Blend Images Together (default) and Geometric Distortion Correction.  Press OK. (see below)

Wait a few moments for Photoshop to do it's magic and below is the result!

Below are the two layers Photoshop created


Because I like to go back incase I make a mistake I will now duplicate the layers and then merge the duplicates. Now that the layers are merged I can crop the images to my liking.  There were a few spots in the sky that I wanted to keep so the crop had a couple of empty areas on the bottom. (see below)

Below I used the clone brush I fill in the blank areas being careful to make sure there are no repeated patterns.

Below is my original image

Obvious Keystone Vertical Objects Removed (below)

Using Vertical Lens Correction (below)

Using Photo Merge with two purposely taken images.



(James A. Rinner) Correcting Effect Keystone Photoshop Ultra-Wide https://jamesarinner.zenfolio.com/blog/2017/1/correcting-ultra-wide-keystone-effect-in-photoshop Wed, 25 Jan 2017 23:55:44 GMT
Being Vintage https://jamesarinner.zenfolio.com/blog/2016/12/vintage Ansel Adams Darkroom Mag InterviewAnsel Adams Darkroom Mag Interview"We've gone through the silver image, the dye color image, and I think the next one will be the electronic image. I hope I am around to see it." - Ansel Adams

The word "vintage" is used when thinking about high quality items from past times. (Vintage cars, wine, music, cameras...) When it comes to vintage, not antique, photographs I immediately think of Edward Weston, Brett Weston, Morley Baer and of course, Ansel Adams. When I was a young man in my twenties and thirties, Ansel Adams was alive and giving workshops. I never had the opportunity to meet him, but did correspond with him a couple of times. If there was a local gallery showing of his work, I would be there.

The art of making photographs through silver halide film is pretty much lost to the general and professional photographer today. When the weight, bulk and cost of film limited us to how many photographs we could shoot during a location shoot, whether it was for a client or stuffed into a backpack, we chose our subjects, composition and exposure very carefully. I think this is a practical education that is also lost to the modern photographer. In those vintage days of the past every click of the shutter cost you more than 1/125th of a second of your time, but cash from your pocket.

Today we have our digital cameras that can give you an acceptable exposure almost 100% of the time. Our cameras have built-in filters that change a mundane photograph into something cool, different or even (shudder) black and white! Once we have a proper exposure we can download it to our computer, load it into a post-processing program and edit the photograph to our hearts content. We can run the image through a "preset" that will give us a new look like low-key, high-key, film noir or full dynamic, to just name a few of the 38 presets in the NIK Silver Effex Pro 2 Photoshop plug-in. I am waiting for the day when some software engineer is going to write an algorithm that lets you select a certain photographer, let's say Ansel, and you move the camera around till your screen blinks, whistles or rings when the composition matches something Ansel would take.

I want to encourage you to take the above vintage approach to photography. Take your time when photographing your subject. Think of the classic rules of composition and use them to your advantage. Here is one quick way to slow you down; put your camera in manual mode! Look at the f-stop and shutter speed you are using and think about how they affect your photograph. In the Darkroom magazine interview (see opening image), Robert Holmes asks Ansel "Where do you recommend people study (photography) today?" Ansel answers with this "... It takes 10 years to master basic techniques in other arts so why expect photography to be easier? Actually, I wouldn't like to think that anyone could really master photography technically or expressively within 10 years..."

In closing I want to finish with this last quote of Ansel Adams from the interview. "We've gone through the silver image, the dye image in color, and I think the next one will be the electronic image. I hope I'm around to se it." Had Ansel been around today he would be teaching us how to use PhotoshopAA! Okay, that was an inside to joke for all us PhotoshopCC users, but he would have mastered the program and probably used it in ways we would never think of. Now go out and be vintage!

(James A. Rinner) Adams Ansel Darkroom Vintage interview photography https://jamesarinner.zenfolio.com/blog/2016/12/vintage Sat, 31 Dec 2016 20:02:04 GMT