Many photo post-processing editors feature “layers”, several images at the same time. Here we use Corel PaintShop Pro to illustrate layers and a couple blend modes.
Blend modes allow combining layers in different ways.
After you open an image you can make additional layers. Show the Layers Palette. Right-click the little image in the sidebar and duplicate it a couple of times. The sidebar has several columns as you can see in my illustration here.
In the Layers pane there is a little image of each layer. Next to the right is the “Blend Mode”. The default is “Normal”. Click on that and you will see a listing of the various modes.
Here I will describe the use of just two of the, Multiply and Screen. As an illustration I will use an image of a painting from the Cleveland Museum of Art that is very faded and “washed out”.
Next I multiply two layers of this image with each other. Think of the pixel values as going from zero to one for black to white. When a value of 0.4, a gray area, is multiplied with itself (i.e. 0.4 x 0.4) we get 0.16 a much lower value and much closer to black (zero), a much darker gray. Multiplying 0.8, a fairly light value, with itself gives 0.64 again a darker gray. All of the results stay within the zero to one range. Thus we don’t burn any highlights nor cut of any pixels on the black end.
What we do get is a darker image with higher contrast.
SC-PSP-blend-mode
Right-clicking in the blue area gives options including merging the layer with the next lower one. I did that, duplicated the layer again and multiplied the layers one more.
The result is dark. Another duplication and then using the blend mode “Screen” gives us a very nice, acceptable image. Screen adds the two layers together, again without burning out any highlights or making any shadow areas totally black.
See – just a few clicks and we went from a nearly worthless image to a fine one.
Summer – 1891 -Pierre Puvis de Chavannes – (French, 1824–1898)
Now we have that painting looking more like what it was like when the painter was finished with it.
Blend modes are very useful and can give interesting effects. Play with them, you will have fun and find good uses.
Sometimes a photo turns out to look rather flat, without any “pep”. There can be many reasons for that, flat lighting is one. But let’s concentrate on how to enhance such a photo.
The first consideration should be to increase the contrast.
Here is an example:
Every post-processing editor has a contrast slider.
Here, in the image above, you can see how the contrast slider has pepped up the photo.
Another thing to watch for is a limited range in the histogram. If you see some “unused” space at either end of the histogram data, move the histogram sliders to where the histogram data starts.
The example here shows that the histogram data does not reach all the way to the left end. That means the photo does not have any intense blacks. Moving the left (blacks) histogram slider to the right until it gets to where the graph shows some values can make the image significantly better.
Here is an example of a photo that has a limited range showing in the histogram. There is no data on almost half of the right end – the photo is significantly underexposed.
Now here is the same image with both histogram sliders moved to spread out the available data over the range of brightness levels.
See how even poor photos can be rescued and result in photos that you can show and share.
Short answer: It doesn’t. — A tilt-shift lens does not correct the perspective distortion that we often call “falling-over building syndrome”. What it does is to let the photographer avoid the problem.
Here is an illustration of what we are talking about.
The narrowing at the top is just the way imaging works. You see it anytime you look up at a building. Our visual system interprets it for us when we stand in front of the building, but when we see it in a photo it just doesn’t look right.
The problem arises from titling the camera upward. If the plane of the sensor is parallel with the vertical structure, there will be no falling-over building syndrome, “FOBS”.
This photo illustrates how buildings look “right” when the camera is not tilted, held level and aimed so the horizon is in the middle of the frame.
Buckhead
We get way too much sidewalk that way, but it works! Cropping can get us what we want.
Sometimes the camera angle of view does not include all we want when the camera is level. Here is an illustration of that.
The left image models the view with a regular camera lens. The yellow frame simulates the sensor size and shows what the result would be. Note that the building is only partially included.
On the right is an illustration of what shifting of the lens accomplishes. The image is shifted relative to the sensor so all of the building is within the frame. Only the lens shifting is needed for this “correction”, the tilting part of the lens is not used for avoiding the perspective distortion.
There is also a hint there that the image size produced by a tilt-shift lens is much larger than what is produced by a normal lens. The reason, of course, is so different parts of the image can fully illuminate the sensor when the image is moved around. This also makes the optics of such lenses more demanding and expensive.
This is a photo of the Nikon PC Nikkor 19mm 1:4 E ED wide-angle tilt-shift lens. Notice how the whole lens is shifted relative to the lens mount. The range of this lens is 12 mm in either direction. That is half the height of the full frame sensor (about 24 by 36 mm). If you do architectural photography this is a very useful tool.
Photo files contain a lot of information besides the image. We generally refer to that as the EXIF data although there is actually a lot more, a better term to use is metadata. Cameras add data about the camera and its settings in an area outside the image data. Smartphones do the same and also add GPS data to show exactly where the picture was taken. The apps used to do post-processing add entries of their own, delete some that are there, and alter some information. We all like to add some tags, comments, titles and descriptions of our own. By the time a photo is ready for sharing on the internet it carries quite a data load.
The photo illustrating this post has a small portion of its metadata superimposed. I ran it through several apps and did a variety of processing including removing the background, enhancing the colors, sharpening and noise removal. Then I sized it down for online use. When I was finished the metadata was 10.1 kilobytes in size. How do I know> I use an app called EXIF Tool. That app can list pretty much all metadata that can be found in a file. It can also be used to add or remove data. More on that shortly.
Since much of this data is personal to us it might not be good to share all that on the internet. There are a number of ways to modify the metadata. I will share here just two approaches for removing metadata. I will also limit this discussion to JPG photo files and Windows PCs as the storage and processing devices.
The Windows “Properties” App
When you right-click an image file a small menu window pops up. The last option is “Properties”. Clicking that choice brings up a small window something like this example shown on the left:
Notice that option on the bottom: “Remove Properties and Personal Information“.
Clicking that brings up another window, as shown on the right above, with options.
The default option is “Create a copy with all possible properties removed“. It turns out that “all possible” is a rather limited promise. When you click the second option, “Remove the following properties from this file:” That allows you to scroll through the many data items. Those that can be removed have a check box in front. There are many other properties that are not listed. Some of the listed options are shown in the illustration on the right above. You can see the other data items for our sample photo in these illustrations.
Removing “all possible” data from our sample photo file reduced the metadata to 7.99 kB. Nearly 80% of the data remained in the photo. This method did remove personal information and location data and most of the photo information. What was not removed included all sorts of information generated by the post-processing apps, like a history of all the steps done. You might not want to share all the steps you did in making your photo into your masterpiece. So you might want to remove all that is still in there.
Using ExifTool to remove metadata
The program ExifTool is a very powerful application. There are many option and if you look at the instructions for its use, you will be tempted to throw up your hands. Yes, this tool is for the geeks and nerds, but it can be used by normal humans. You can download the tool from exiftool.org. The downloaded file is a zip file. Move it to a convenient folder and extract the contents (right-click > Extract All).
The extracted contents consists of just one file with the strange name exiftool(-k).exe.
Right-click on that file and select Send to, then Desktop (create shortcut). You might want to rename the shortcut something like “Show EXIF“. Really, that all there is too it for the option that shows the metadata in a file. All you need to do is drag the thumbnail from the directory to the desktop shortcut.
The first time you do that Windows will complain. In that window click More Info. In the next window click Run anyway. See the illustrations below.
The tool will run and you will get the listing of the metadata in a CMD window. On subsequent attempts the warning window will not show, the tool will run right away and you will get your information.
So far what I described is a way to see the metadata. To remove it takes another bit of “installation work”.
Installing the Metadata Removal option
Here are the steps for adding a removal tool option. Please follow them carefully.
Open the folder where you installed ExifTool.
Copy the file – Ctrl-C.
On an empty spot in that folder paste the copied file – Ctrl-V.
Right-click the file copy and select Rename. The file name will be highlighted so you can edit it.
Rename the file so that the new name is exiftool(-all=).exe
Make absolutely sure that the new file name is as specified above, including the hyphen and the equal sign.
Make a desktop shortcut just the way you did before.
Make a folder on the desktop (right-click an empty spot > New > Folder ).
Give the folder a name like “Remove EXIF“.
Drag the new shortcut into this folder.
Rename the shortcut something like “Remove EXIF“.
Do I see your hand raised up trying to interrupt me? You are saying that renaming a file can’t possibly make it function differently? Back in the days of the old bard “a rose by any other name smelled just as sweet”, but in this day and age with very clever programmers, what you have done is indeed changing the function of the file by just renaming it.
You now have an extremely powerful tool that can remove the metadata and leave just enough to allow an image file to still function normally. So let me tell you a little more and also allow me to admonish you.
DANGER – DANGER – DANGER
Using this tool can damage files beyond repair.
Never remove the metadata from your original files.
Never remove metadata from RAW files (as produced by your camera).
Never remove metadata from intermediate post-processing files.
If anybody else, especially a child, has access to your computer, remove this file to avoid catastrophies.
Always prepare copies of your files. Remove the metadata only from final copies.
How do you use it?
Open the folder with the photos you wish to strip of their metadata.
Open the folder with the ExifTool for removing the data.
Drag the thumbnail of the photo over to the ExifTool.
That’s it.
Why do I have you put the removal tool shortcut into a folder? So it takes an extra step and so that you are sure of what you are doing.
When you then drag the photo thumbnail to the viewing tool, you will see what metadata remains. It will look somewhat like this:
Just in case you ignored all my warnings and stripped the data from a photo that you should not have, there is a safety feature. Inspect the screen capture above. Note the added file in the photo folder with the funny name. The ExifTool made a copy of the file as it was before the metadata was removed. It appended “_original” to the filename extension. If you edit the filename and remove that part, what you have is the file as it was before the operation.
Now you can relax and go about removing metadata from photos.
.:. © 2026 Ludwig Keck
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