10 Steps to Processing Nightscapes & Time-Lapses
By: Alan Dyer
Tags: Advanced Stacker Actions, Alan Dyer, astrophotography, Camera Raw, how-to, Lightroom, LRTimelapse, nightscape, non-Destructive, Photoshop, Photoshop layers, processing, Raw processing, Sequence, StarCircleAcademy, technique, time-lapse, tutorial
Category: Tips and Techniques
|Camera:||Canon EOS 6D|
NOTE: Click on any of the screen shots below for a full-res version that will be easier to see.
In my preferred “workflow,” Steps 1 through 6 can be performed in either Photoshop (using its ancillary programs Bridge and Adobe Camera Raw) or in Adobe Lightroom. The Develop module of Lightroom is identical to Adobe Camera Raw (ACR for short).
However, my illustrations show Adobe Bridge, Camera Raw and Photoshop CC 2014. Turn to Photoshop to perform advanced filtering, masking and stacking (Steps 7 to 10).
To use Lightroom to assemble a time-lapse movie from processed Raw frames you need the third-party program LRTimelapse, described below. Otherwise, you need to export frames from Lightroom – or from Photoshop – as “intermediate” JPGs (see Step 6), then use other third party programs to assemble them into movies (Step 10B).
Use Adobe Bridge (shown above) or Lightroom to import the images from your camera’s card.
As you do so you can add “metadata” to each image – your personal information, copyright, keywords, etc. As you import, you can also choose to convert and save images into the open and more universal Adobe DNG format, rather than keep them in the camera’s proprietary Raw format.
Once imported, you can review images, keeping the best and tossing the rest. Mark images with star ratings or colour labels, and group images together (called “stacking” in Bridge), such as frames for a panorama or “high dynamic range” set.
Always save images to both your working drive and to an external drive (which itself should automatically back up to yet another external drive). Never, ever save images to only one location.
Open the Raw files you want to process. From Bridge, double click on raw images and they will open in ACR. In Lightroom select the images and switch to its Develop module.
In Adobe Camera Raw be sure to first set the Workflow Preset (the blue link at the bottom of the screen) to 16 bits/channel and ProPhoto RGB colour space, for maximum tonal range. This is a one-time setting. Lightroom defaults to 16-bit and the AdobeRGB colour space.
The Basics panel (the first tab) allows you to fix Exposure and White Balance. For the latter, use the White Balance Tool (the eyedropper, keyboard shortcut I) to click on an area that should be neutral in colour.
You can adjust Contrast, and recover details in the Highlights and Shadows (turn the latter up to show details in starlit landscapes). Clarity and Vibrance improves midrange contrast and colour intensity.
Use Command/Control Z to Undo, or double click on a slider to snap it back to zero. Or under the pull-down menu in the Presets tab go to Camera Raw Defaults to set all back to zero.
The Detail panel allows you to set the noise reduction and sharpness as you like it, one of the benefits of shooting Raw.
Generally, settings of Sharpness: Amount 25, Radius 1 work well. Turn up Masking while holding the Option/Alt key to see what areas will be sharpened (they appear in white). There’s no need to sharpen blank, noisy sky, just the edge detail.
Setting Noise Reduction: Luminance to 30 to 50 and Color to 25, with others sliders left to their defaults works well for all but the noisiest of images. Luminance affects the overall graininess of the image. Color, also called chrominance, affects the coloured speckling. Turning the latter up too high wipes out star colours.
Turn up Color Smoothness, however, if the image has lots of large scale colour blotchiness.
Zoom in to at least 100% to see the effect of all noise reduction settings. Adobe Camera Raw and Lightroom have the best noise reduction in the business. Without it your images will be far noisier than they need to be.
Wide angle lenses, especially when used at fast apertures, suffer a lot from light falloff at the corners (called vignetting). There’s no need to have photos looking as if they were taken through a dark tunnel.
ACR or Lightroom can automatically detect what lens you used and apply a lens correction to brighten the corners, plus correct for other flaws such as chromatic aberration and lens distortion.
Use the Color tab to “Remove Chromatic Aberration” and dial up the Defringe sliders.
For lenses not in the database (manual lenses like the Rokinons and Samyangs will not be included, nor will any telescopes) use the Manual tab to dial in your own vignetting correction. This can take some trial-and-error to get right, but once you have it, save it as a Preset to apply in future to all photos from that lens or telescope.
I usually apply Lens Corrections as a first step, but sometimes find I have to back it off it as I boost the contrast under Basics.
For a small number of images you could open them all, then Select All in ACR to apply the same settings to all images at the same time.
Or you can adjust one, then Select All and hit Synchronize.
Another method useful for processing dozens or hundreds of frames from a star trail or time-lapse set is to choose one representative image and process it. Then in Bridge choose Edit>Develop Settings>Copy Camera Raw Settings. If you are in Lightroom’s Library module, choose Photo>Develop Settings>Copy Settings.
With either program you can also right-click on an image to get to the same choices. Then select all the other images in the set (Command/Control A) and use the same menus to Paste Settings.
A dialog box comes up for choosing what settings you wish to transfer.
If you cropped the image (a good idea for images destined for an HD movie with a 16:9 aspect ratio), pick that option as well. In moments all your images get processed with identical settings. Nice!
You now have a set of developed Raw images. However, the actual Raw files are never altered. They remain raw!
Instead, with Adobe Camera Raw the information on how you processed the images is stored in the “sidecar” XMP text files that live in the same folder as the Raw files.
In Lightroom’s case your settings are stored in its own database, unless you choose Metadata>Save Metadata to File (Command/Control S). In that case, Lightroom also writes the changes to the same XMP sidecar files.
To convert the images into final Photoshop PSDs, TIFFs or JPGs you have a couple of choices. In Lightroom go to the Library module and choose Export. It’s an easy way to export and convert hundreds of images, perhaps into a folder of smaller JPGs needed for assembling a time-lapse movie.
To do that from within Adobe Bridge, select the images, then go to Tools>Photoshop>Image Processor. The dialogue box allows you to choose how and where to export the images. Photoshop then opens, processes, and exports each image.
For a folder of images intended to be stacked into star trails (Step 10A) or time-lapse movies (Step 10B), you’re done processing.
But individual nightscape images can often benefit from more advanced work in Photoshop. The next steps make use of a non-destructive workflow, allowing you to alter settings at any time after the fact. At no time do we actually change pixels.
One secret to doing that is to open an image in Photoshop and then select Layer>Smart Objects>Convert to Smart Object. Or go to Filter>Convert for Smart Filters.
OR … better yet, back in Adobe Camera Raw hold down the Shift key while clicking the Open Image button, so it becomes Open Object. That image will then open in Photoshop already as a Smart Object, which you can re-open and re-edit in ACR at any time later should you wish.
Either way, with the image as a Smart Object, you can now apply useful filters such as Reduce Noise, Smart Sharpen, and Dust & Scratches, plus third-party filters such as Nik Software’s Dfine 2 Noise Reduction, all non-destructively as “smart filters.” They can be re-adjusted or turned off at any time.
The other secret to non-destructive processing is to apply adjustment layers.
Go to Layer>New Adjustment Layer, or click on any of the icons in the Adjustments panel. If that panel is not visible at right, then under the Window menu check “Adjustments.”
This panel is where you can alter the colour balance, the brightness and contrast, the vibrancy, and many other choices. I find Selective Color most useful for tweaking colour.
Curves allows you to bring up detail in dark areas. Levels allows setting the black and white points, and overall contrast.
The beauty of adjustment layers is that you can click on the layer’s little icon and bring up the dialog box for changing the setting at any time. You never permanently alter pixels.
The image adjustment “Shadows & Highlights” is also immensely useful, but appears as a smart filter, not as an adjustment layer. It’s one of the prime tools for creating images with great detail in scenes lit only by starlight.
The power of adjustment layers is that you can apply them to just portions of an image. This is useful in nightscapes where the sky and ground often need different processing.
To create a mask first select the region you want to work on. Try the Quick Selection Tool (found near the top of the Tool palette at left). Use it to brush across the sky, or the ground, so that the entire area is outlined by “marching ants.”
Use the Refine Edge option to tweak the selection by brushing across intricate areas such as tree branches.
Once you have an area selected, hit one of the Adjustments to add an adjustment layer with the mask automatically applied. Double click on the mask to tweak it: hit Mask Edge to clean up the edge, or turn up the Feather to blur the edge.
To apply the same mask to another adjustment layer, drag the mask from one layer to another while holding down the Option/Alt key.
Invert the mask (or select it and hit Command/Control I) to apply it to the other half of the image. Paint the mask with black or white brushes if you need manually alter it. Remember – black “conceals,” while white “reveals.”
When done, be sure to always save the image as a layered “master” .PSD file.
Never, ever flatten and save – that will wipe out all your non-destructive filters and adjustment layers.
If you need to save the image as a JPG for social mediia or emailing, then Flatten and Save As … Or use Photoshop’s File>Export>Export As .. function.
Step 10A – Photoshop or 3rd Party Programs – Stack for Star Trails
One popular way to shoot images of stars trailing in arcs across the sky is to shoot dozens or hundreds of well-exposed frames at a fairly high ISO and wide aperture, and at a shutter speed no longer than 30 to 60 seconds. You then “stack” the images to create the equivalent of one frame shot for many minutes, if not an hour or more. The image above is an example.
There are several ways to stack.
From within Photoshop CC (or using an Extended version of the older CS5 or CS6) one method is to go to File>Scripts>Statistics. In the dialog box, drill down to the images you wish to stack (put them all in one folder) and choose Stack Mode: Maximum, and uncheck “Attempt to Automatically Align.” The result is a huge (!) smart object. This method works best on just a few dozen images. In this case, you’ll need to use Layers>Flatten to reduce its size.
Other options for stacking hundreds of images include the free program StarStax (Windows and Mac), which requires a folder of “intermediate” TIFFs or JPGs. See Step 6 above.
The same folder of images taken for star trail stacking can also be turned into a time-lapse movie. Instead of stacking the images on top of one another in space, you string them together one after the other in time.
There are many methods for assembling movies. Free or low cost programs such as Quicktime 7 Pro, Time-Lapse Assembler, Sequence (a Mac program shown above), VirtualDub, or Time-Lapse Tool can do the job, all offering options for the final movie’s format.
Generally, an HD video of 1920×1080 pixels in the H264 format, or “codec,” is best, rendered at 15 to 30 frames per second.
Most movie assembly programs will need to work from a folder of JPGs of the right size, produced using one of the choices listed under Step 6: Export.
But … you can also use Photoshop to assemble a movie.
Choose the Window>Workspace>Motion to bring up a video timeline. Then File>Open to drill to your folder of processed and down-sized JPG files. Select one image, then check “Image Sequence.” Choose the frame rate (15 to 30 fps is best). Then go to File>Export>Render Video to turn the resulting file into a final H264 or Quicktime movie suitable for use in other movie editing programs.
Advanced Techniques: Using LRTimelapse
The workflow I’ve outlined works great when you can apply the same development settings to all the images in a folder. For star trail and time-lapse sequences shot once it gets dark and under similar lighting conditions that will be the case.
But if the Moon rises or sets during the shoot, or if you are taking a much more demanding sequence that runs from sunset to night, the same settings won’t work for all frames.
The answer is to turn to the program LRTimelapse (100 Euros for the standard version, and available in a free but limited trial copy). LRTimelapse works with either Lightroom or Bridge/Adobe Camera Raw.
To use it you process just a few selected “keyframes” – at least two, at the start and end of the sequence, and perhaps other frames throughout the sequence, processing them so each frame looks great. You read that processing data into LRTimelapse and, like magic, it interpolates your settings, creating a folder of images with every setting changing incrementally from frame to frame, something you could never do by hand.
It can then work with Lightroom to export the frames out to a video in formats from HD up to 4K in size. For serious time-lapse work, LRTimelapse is an essential tool.
Much, much more information and tutorials are included in my multimedia Apple eBook, linked to below.
But I hope this quick tutorial helps in providing you with tips to make your images and movies even better! If you found it useful, please feel free to share a link to this blog page through your social media channels. Thanks!
And for tips on shooting in the field, please see my earlier blog on Ten Tips for Terrific Time-Lapses.
– Alan, November 10, 2015 / © 2015 Alan Dyer / www.amazingsky.com