Tag Archives: color range

Sneaky Night (and Daylight) Photo Processing Tips

3 Replies

 

Did you attend the Sneaky Night (and Daylight) Photography Processing Tips event held at Adobe in San Jose, California on July 23, 2018? Welcome!

The topics covered include these:

Let’s Start With a Pop Quiz

The Equation…

Or asked another way. Do these look like they might be the makings of an interesting shot?

Three Nuns Thumbnails

The Answer To the Pop Quiz

Combining the images shown in the thumbnails, nets this Interesting star trail.

N-604259-361lstr

“Long Streaks” Star Trail from 112 separate photos

Creating the Star Trail component above is discussed in detail in our NP105: Creating Star Trails & Timestacks Webinar – it’s an interactive 2 hour course with notes, a recording, and practice files. We run that webinar approximately quarterly next event is July 25th. Details  covered include how to set up the shots, configure the camera settings, and combine the images using various tools.

Adding that bright frame with a bit of selection and masking to the star trail image nets this:Reaching for the Sky

And that MUST be interesting because it garnered 80,000 views in just a few days. How do you do this bit of Photoshop Magic? Over the years, we’ve shown quite a few methods for accomplishing this. For example in Foreground – o – Matic we illustrated how to use the quick selection tool. That may work well here because the rock has a nice crisp boundary. Other methods that may work include “thresholding” and Color Range selection.

Thresholding to create a mask:  We’ve described this before. Briefly this is how it works. Select one of the images – one with contrast between the sky and foreground.  Duplicate that image (Ctl/Cmd -> J). Then use Image -> Adjustments -> Thresholds and slide the carat left or right until it has selected what you want (mostly black or white). Paint out the stray areas with either a 100% black or white brush as appropriate.  When done, you have an image you can use as a layer mask. The trick to doing this is to select the black and white image, EDIT an existing layer mask, and paste the black and white image as the layer mask.

 

Photoshop Processing Tips

  • Do work on a calibrated free-standing display in a dim, consistently lit room.
  • Do NOT attempt to process important images on a laptop monitor. You will frustrate the dickens out of yourself trying to get consistent color, brightness, and so forth on a laptop monitor or in an uncontrolled lighting environment. The monitor display angle can cause subtle to dramatic differences in color, saturation, brightness.
  • Do make an action and assign it to a hot-key if you find yourself repeating that operation frequently… E.g. I have an F9 key to apply a contrast enhancement adjustment curve
  • Do name your layers sensibly. You may save yourself a world of hurt.
  • Do NOT crop too early – save this step for last.
  • When combining dark and light subjects (e.g. daylight-like and night) it’s usually best to have very crisp selections – not feathered selections.

Gallery of Photoshop Hot Keys

These hot-keys are described for Windows users. I use these ALL the time. Some have no menu equivalent. You can translate from Windows to Mac as follows:

Ctl -> Command
Alt -> Option
Shift -> Shift

Layer / Layer Mask shortcuts:

  • Duplicate layer dialog allows you to duplicate into another/new document!
  • Ctl-J: Duplicate the current layer
  • Ctl–Alt–Shift-E   Merge visible layers to a new layer as a COPY.
  • Shift–click on layer mask to turn it off or on.
  • Ctl–drag layer mask to move it to another layer.
  • Shift–drag a layer mask to Invert it and move it to another layer
  • Alt–click a layer mask to EDIT it.
  • Alt–drag a layer mask to copy it. Toss in Shift to invert the mask.
  • Shift–click a layer mask to turn it on/off
  • Alt–click quick mask icon to create an inverse layer mask from a selection
  • Do not be afraid to duplicate and adjust a layer for the sole purpose of creating a mask!

Selection shortcuts:

  • Ctl–click on layer mask to create a selection from that layer mask.
  • Ctl–click on a channel e.g. RGB, R, G, or B to make a selection based on brightness.
  • Sometimes Select -> Modify -> Expand or Contract (by 1 pixel) helps to fine-tune a selection. Feathering seldom works well for compositing light and dark images.


Sneaky Tips
Sneaky Tips
Notes from "Sneaky Tips for Processing Day and Night Photography"
Price: $2.00

Darken Mode Stack Tip Using AdvancedStacker PLUS 18

Leave a reply

Published: March 15, 2018

The new Advanced Stacker PLUS 18 is our attempt to make processing simpler. One of the things we find we often do is run multiple stacks (Lighten, Darken, Streaks, etc) to determine which effect(s) work the best. Well, we did something for the first time that worked REALLY well, so we will start by sharing that, even though Advanced Stacker PLUS 18 is not yet ready for publication.

In a nutshell, we created this:

Orion, Falling

From this:

Long Streaks Stack Result – no modifications  f/4, ISO 1600, 15 Seconds. Nikon D600, 24mm x 250

There are several obvious differences between these images.

  1. Because there was strong moonlight (and other light), the sky is over-bright and lacks contrast.
  2. The wind together with surrounding lighting (including flashing red lights from a passing fire truck) caused strange artifacts in the palm trees.
  3. Different colored light sources lit the palm trees differently (notice the really cyan colored palm fronds in the second tree from the left).
  4. There was utility wiring intruding into the image.

The Processing

Stacker 18 allows you to simultaneously stack in multiple modes. For example, to create this effort I used Lighten, Long Streaks, Darkest, and Average modes. I ended up NOT using Lighten or Average modes in this case. Is there extra overhead keeping more stacks? Yes, there is. However we’ve paired down the stacks to as few frames as possible to keep the overall footprint low.

Once the stacking had finished, the result of the Long Streaks was a bit unappetizing due to the red and other artifacts in the trees (see second image). However the Darkest mode stack effectively removes all of the stars – and as it happens, all of the strange highlights in the trees.  First we applied a Curves adjustment layer to the Long Streaks and darkened it.

Blending a Clean Foreground with the Star Trails

Darkest Stack results

The next operation was to find a way to blend the darkest mode stack (right) with the Long Streaks stack while preserving the star trails  and getting the cleaner looking foreground.

 

Duplicate the Darkest mode result (it’s a single layer) on to the Long Streaks stack. Then drag the darkest mode stack to the top layer. Set the new layer blend mode to normal, 100%.

Next we need to mask out the sky of the Darkest stack so that the long streaks will show through. The tool for that is to use Select -> Color Range. Holding down the shift key allows you to click multiple areas of the sky to add to the selection. You can vary the fuzziness of the selection to determine how closely the color has to match the sample. The mask will probably need some manual cleanup afterward, but as you can tell from the selection in the image below, just clicking different areas in the sky produced almost exactly what is desired.

Photoshop Color Range Selection

After pressing OK you get a selection. The next step is Layer -> Create Layer Mask from Selection -> Hide Selection Once you have a mask, you can paint on it to clean up any artifacts. Adjust the opacity of the darkest layer to make it “look right”. In this example, the combined image looked best at about 93% opacity.

Correcting “Off” Colors Due to Light Source Issues

The penultimate step was to create a Hue and Saturation adjustment layer. Lock the adjustment to the Darkest layer (hold the Alt/Option key and click on the boundary between the adjustment and the darkest layer). Then click the “Finger selection”  (just below the word Presets). Now there is an eye-dropper which you use to select the color that needs correction. In this case, clicking the dropper on the cyan colored palm frond is the right move. Adjust the saturation slider way down, lightness down, and fiddle with the hue to make the bizarre color more natural.

Aggressively toning down the cyan colored palm fronds

Removing Wires (and other distractions)

Finally we also used the Spot Healing Brush tool to “heal out” the utility wires. Here is a short-cut for healing out a straight line. Click the beginning of the area with the spot healing brush, then hold shift and click the end of the line. Shift causes the brush to be applied in a straight line between the first and second clicked points. The shift-trick works with almost all brushes. Two other tricks with the spot healing brush tool are to:

  • Start where the surrounding area has a predictable substitution (not a busy area) and work outward from there
  • Use as small a brush as you reasonably can

For example you can adjust the spot healing tool brush size to about double the width of the utility line, then click the healing brush tool where the arrows point below. Next work your way outward toward the tree on one side, then the other.

Summary

Here is a summary of the steps taken – not including the palm frond “naturalization” or spot healing described above.One more trick worth noting… the histogram shown on the Curves adjustment will give you a clue what may need adjustment.

Want to know what we consider the top 5 most used photo editing skills? Read here (and part 2 and part 3).