A time exposure at Mauna Loa Observatory, lasting a little over an hour, produced star trails as Earth rotated. (Jonathan Kingston/Aurora Select for the New York Times)

What are Star Trails?

Simply stated, star trails are the streaks in a photograph left by stars during a time exposure as the Earth rotates.  Objects in the foreground of the photograph remain sharp as they are not moving relative to the camera, while the stars, depending on which cardinal direction the camera is facing, will form concentric circles or streaks in the sky.

Why does Photographing Star Trails require a different technique with a Digital SLR?

In order to capture star trails, one must leave the shutter open on the camera for a long amount of time, often for more than an hour.  This allows time for the earth to rotate and form the streaks associated with star trails.  With film one simply set the camera to the “bulb” setting, locked open the shutter with a cable release, and returned a few hours later to close the shutter.  This method unfortunately does not work well digitally as one of the drawbacks of digital SLR photography circa 2011 is the longer the shutter remains open, the more the image degrades with visual grain, otherwise known as digital noise.

The solution is to slice the single long exposure one would have used for a film capture, into many small separate time slice exposures and then combine them back together into a single frame with a technique known as “Stacking”.  Dan Newton of Liquid In Plastic has written an excellent post HERE on how to photograph star trails using the stacking technique.  I suggest you read it before proceeding.

How to stack your star trail time slices into a single image in Photoshop:

I recommend using Dan Newton’s ”Method 2″ to stack your star trail image slices into a single image in Photoshop.  For a large part of this year the page that Mr. Newton linked to in Method 2 (Chris and Dawn Schur’s photoshop action) was broken, so I have taken the liberty to re-record their action verbatim and make it available for download on this website.

Downloading and loading the star trail stack action into Photoshop

1) Click here to download the Star Trails Photoshop Action.
2) UnZip the file.
3) Copy the action into the Photoshop>Presets>Actions folder.  On the Macintosh the pathway is as follows:  Applications>Adobe Photoshop CS5>Presets>Actions.
4) Open Photoshop and click on the Actions Palette (Window Menu>Actions).
5) In the upper right hand corner of the Actions Palette click the icon with four small horizontal lines.  A drop down menu will appear.  Scroll down and click “Load Actions…”.
6) A finder (explorer) window will open.  Navigate back to your Photoshop>Presets>Actions folder, highlight the “Kingston Startrails Stacker.atn” and click “Open”.
7) In your actions palette you should now see a action called “Kingston Startrails Stacker”.

Running the Startrails Stacker Action in Photoshop

1) Open the dark frame that Mr. Newton talks about in his blog post in Photoshop.
2) Go to the File>Automate>Batch menu in Photoshop:

• Under the “Play” box select the Set: “Kingston-Startrails-Stacker” and the Action: “Star Trails Stacker”
• Under the “Source” set the drop down menu to “Folder” then click the “Choose…” button and select the folder that contains all of your star trail image slices.
• Be sure that “Suppress File Open Options Dialogs” is checked
• Be sure that “Suppress Color Profile Warnings” is checked

3) Click “OK”.
4) Wait while Photoshop assembles the stack.  You will see a bunch of images opening and closing in rapid succession.
5) When Photoshop is finished go to File>Save and give the resulting file a relevant title.

Dan Newton has some excellent suggestions on modifying the  action under his “Method 2″ section here that I suggest you experiment with.

That’s it – Star Trails 101!

Watch how to create startrails using the stacking method the in the following video:

In the following video I demonstrate the above steps as well as show you how to use a Star Trails Photoshop Droplet that you can download HERE to further automate the stacking process.

How to create a Star Trail image using a Photoshop Action from Jonathan Kingston on Vimeo.

How to load and use a star trails Photoshop action to stack multiple, consecutive exposures into a single frame to create a star trails image.

THE PROBLEM

I recently ran into a rather big problem in the iOS world.  I completely filled up my phones 32 gigs of memory with photos, and realized to late that it is not terribly efficient to delete them manually on the phone.  I have had my iphone for a couple years and have always chosen the “keep photos” option after downloading the images into iPhoto – which I use solely to manage my iPhone images – preferring Lightroom to manage the library for my ‘big boy’ cameras.

iPhoto gives you the option to delete photos after every download, however if you press the "Keep Photos" button as I often did, it will not give you the option to delete those specific images ever again.

When my iphone indicated that its’ memory was full, I figured that I could simply plug the iphone into my computer, browse to the iphones photo library in iPhoto or Finder, and delete the photos as a batch.  As it turns out, the iPhone’s iOS is set up in such a way that you cannot browse the iphone’s photo library like you would a digital camera’s memory card using the Finder.  Because the Finder cannot see the iPhone’s photo library, apps like Adobe Bridge and Lightroom also cannot see the iPhones photo library making it impossible to leverage these apps to batch delete the images on my phone.  Not wanting to take the time out of my life to manually delete the images in the iphone’s photo library, I set out looking for another solution to the problem.

THE SOLUTION

The solution of how to delete the photos as a batch from my iphone’s photo library came in the form of a under appreciated native mac os app called image capture.

Image Capture was the only app I could find that could browse the iPhone's photo library and batch delete the images.

Here is how to use Image Capture to access the iPhone’s photo library and batch delete photos from the phone (Note – This is a Mac solution only)

1 – Plug your iphone into your computer.

2 – Go to Applications>Image Capture

3 – Click on your iphone icon

4 – In the right hand column of Image Capture you will see all the images in your iphone’s photo library load.

5 – Select All (Command+A)

6 – Hit the little red delete icon at the bottom of the Image Capture Window.

7 – Wait patiently as image capture deletes all the images in the iPhone photo library.

With Image Capture you can browse and batch or singly delete any image in your iPhone's phones photo library.

That’s it!  Easy as pie.

This is the first time in a number of years I have not participated in the pre-release beta testing for Photoshop, and I must say it is strange to be out of the loop and unconstrained by an NDA.  One thing I know for certain is that Adobe works on 18-24 month product cycles, and CS4 is just about to hit the 18 month mark.  In my humble opinion its lunacy to have such a short product cycle as the consumer barely has time to adopt and learn the updated program before it is depreciated by the next product cycle, but, that being said – everybody gear up for the next life change from Adobe!

DNG Profile Editor

While waiting for the digital delivery of Lightroom 2 earlier this week I was poking around Adobe’s site and stumbled across an application that excites me more than LR 2 – and let me tell you I am really excited about LR 2.  It is a little application called the DNG Profile Editor and it addresses one of the biggest complaints that everybody has with digital RAW files – the unprocessed RAW files lack of richness.  With the introduction of the DNG Profile Editor, our lives are about to change for the better. 

For the savvy reader out there you have probably been using the Adobe Camera Raw calibrator found on the Chromoholics website here to tweak your baseline colors to a truer tonality. Thanks to this website the camera calibration tab did more than languish in obscurity in Lightroom 1 and CS3 and became a very powerful and useful tool in my toolbox. With Adobe’s introduction of the DNG Profile editor, the camera calibration tab has been taken to a new level, and the calibration process takes about 30 minutes less than using the Chromoholics method.

Adobe RAW Camera Calibration Tab

You can download the brilliant DNG Profile Editor application here and Adobe has posted a tutorial on how to use it here.  (Note: you must have an Adobe account to download the application.  Accounts are free and quick to set up).  The basic concept is to begin with a photograph of a set of known color values, in this case a photo of an X-Rite (formerly Gretag MacBeth) color checker chart.  The colors on the chart are known values that the application then uses in its calculations to establish a baseline calibration of your RAW file.

X-Rite Color Checker in the DNG Profiler

1. Here is a screen shot of the first step of the process.  The application is measuring the color patches from my X-Rite color checker chart against known numerical values for the colors.

Fine Tuning Individual Colors

 2. Once the baseline color values are established you can then tweak each individual colors hue, saturation and lightness in a very intuitive interface.  

Create a Custom Curve

3. After tweaking your colors you can fine tune the curve of the image to achieve the exact baseline contrast you desire.

Global Color Fine Tune

5. As an additional step, if you find it necessary, you can further fine tune the RGB color channels along with the overall white point of the file.

Once all these steps have been performed, you can tell LR2 to load the new camera profile as the baseline look for your files.  While this my not seem very exciting at face value, the power and flexibility in creating these profiles means that one could very easily create a set of film looks specifically for your camera and forget the hassle of using presets built for a different systems.  For anyone that shoots the Nikon D3 please feel free to download a Kodak E100 VS type look that I designed here called Nikon D3 CS Boost.  If your on a Mac, install the file in the following place: Home Folder/Library/Application Support/Adobe/CameraRaw/CameraProfiles  

File path on Mac for RAW camera profiles.

I apologize to those on PC as I can’t give you the exact path to install the file, however it will be similar to the path above.  

Once you have loaded the profile and restarted LR, scroll down to the Camera Calibration tab, and in the upper right hand corner of the tab there is a drop down menu where you can choose the profile as seen here:

Adobe RAW Camera Calibration Tab

Note: The profile will only load if you have a D3.  It will not even show up in the list if you are looking at a file from another camera. 

If you don’t want to go through the trouble of purchasing a color checker chart and manually making these profiles, you can download some canned profiles from Adobe here.  I will also be teaching workshops where we do a hands on demo of manually creating the profiles. 

Check back to The Nomadic Photographer regularly for updated profiles to download!

As a professional photographer, one of the parts of my job that I dread the most is keywording.  Send me on a 50 mile hike with 90 pounds of gear, just don’t make me keyword!   Sadly, if I choose to forgo this loath activity, the odds of my images ever being found in an online database are slim to none.  This equals no sales and one very unhappy photographer.  

For those of you who are unfamiliar with the term, keywording is something that you use on a daily basis without knowing it.  Every time you search Google or another major search engine, you are searching key terms or keywords that describe what you are looking for.   To find specific images on the internet, or within a stock photo library like Aurora Photos, the problem is compounded.  The old adage that a picture is worth a thousand words is quite true, however, as a photographer I have to boil down those thousand possible descriptive terms to about twenty five key words that capture the essence of the image.  Once boiled down, I then type these words into the metadata of the file, embed the metadata into the image and get the images online.

Before yesterday, my keywording process would often involve me staring at the computer screen for a few hours with my mind a complete blank.  I would then rally into procrastination mode and read the news, answer all my emails, and daydream about being anywhere but in front of the computer screen keywording. Finally, when I realized I had just wasted a few hours of my life,  I would begin the arduous process of convincing my girlfriend to do my keywording for me.  On a good day, I (she) could get about 30 done. 

This week, a lifeline appeared on the keywording front when Cradoc Software, makers of the much loved FotoBiz, released a product called fotoKeyword Harvester.  I purchased it yesterday, learned the program in about 15 minutes, and in less than an hour had 12 images keyworded and ready for upload.  Now, for me, that is some sort of all time speed record — not even my girlfriend could get it done that fast.  The brilliant idea behind the software is you begin, as the name implies, by harvesting keywords from similar images already online.  You then cull the unnecessary keywords out of this list, fine tune the existing keywords from a brilliantly implemented list of controlled vocabulary built into the program, and export the keywords to your clipboard.  Once the keywords are in your clipboard they can be pasted into whatever program you are embedding the keywords with.  Thank you Cradoc — my girlfriend thanks you too!

A successful week in Ketchum/Sun Valley Idaho and the “Masala of Digital Imaging Techniques” workshop.  The above image was produced by Marcia Duff after a introduction to digital montages in Photoshop CS3.  Photoshop is such a complex behemoth of a program  that it is very refreshing for me to see my participants artistic vision emerge like it did during the workshop.  Great job Marcia and all the other participants who produced fantastic images during the two day event!

I will be teaching six photography workshops in 2008. Other Photoshop courses out there focus on techniques that aren’t applicable to everyday shooting. In my courses, Photography is at the heart of every bit of instruction behind the lens and the computer. The complete workshop schedule with links is posted below. I hope to see you there!

• Photoshop CS3 Digital Workflow for Photographers at the Lepp Institute, San Louis Obispo, CA, February 4 – 8

• Kingston Photo Workshops, Sun Valley, Idaho, Schedule on website

• Rekindling The Creative Spirit at the Hui Ho’olana, Molokai, Hawaii, April 12 – 19
  

• Photoshop CS3 Unlimited for Photographers at the Lepp Institute, San Louis Obispo, CA, May 5-9 and November 10-14

• Digital Workflow using Lightroom at the Lepp Institute, San Louis Obispo, CA, August 4 – 8

For the first time since owning Lightroom, I have experienced a Lightroom catalog becoming corrupted. Fortunately under File>Catalog settings>Metadata, I have been writing my metadata to my .xmp side car files. Unfortunately, I did not realize when a .lrcat file becomes corrupted, the metadata does not include virtual copies of the images, or references to what catalog sets they are in. I hope Adobe changes this in the next release of Lightroom.

To back up a step, I am running a MacBook Pro on 10.5.1, working with Lightroom version 1.3.1 and working off of external hard drives where my library of images lives. Virtual copies and catalog sets are critical parts of my workflow, and I would rather scrub down my bathroom walls with comet than manually reconstruct both of those aspects of a major edit. My .lrcat files reside on the external hard drives, as I don’t have space for them on my laptop, and the particular catalog that became corrupted was comprised entirely of .TIFF film scans. I believe what caused the corruption was going to the Photo>Edit in Adobe Photoshop CS3… command, choosing “Edit Original ” file in Photoshop CS3, applying a rotational change in Photoshop and then saving the file in CS3. When the edited image returned back to LR, it would not display correctly on the screen, and appeared mashed. Upon quitting and re-opening LR, the images displayed correctly on the screen, however the .lrcat file became corrupted.

WHAT DID I DO TO FIX IT?

After testing the integrity of the catalog several times, and trying unsuccessfully to use the built in utility to repair the .lrcat file, Lightroom recommended I visit a website that kindly informed me I was screwed and needed to revert to a backup .lrcat file. I am fairly fastidious about my backups, but the most recent .lrcat file I had on hand was a few days old and would mean loosing three full days of editing. I knew there must be a better way.

Fortunately for me, I was still able to open the corrupted .lrcat database even though it was unable to properly display all of the images in the library. After a lot of trial and error, I came up with a simple, elegant solution for recovering all of the virtual copies and catalog sets from the corrupted database.

THE SOLUTION:

1. If you are still able to open the corrupted .lrcat database, do so. If you can’t get past this step, you are screwed and the following steps will not help you.

2. Click “All Photographs” in the Library module, make sure all filters are turned off, and and choose Edit>Select All from the menu.
3. Go to File>Export as Catalog….
4. From the dialogue box that drops down, choose your desktop as the destination for the exported catalog file, give it a meaningful name (like “corrupted”) and be sure to uncheck the box at the bottom of the window that says “Export negative files” as this will physically duplicate all of the images that are currently in your catalog. NOTE: Whenever I import images into Lightroom, I ALWAYS “Import photos at their current location”.

5. Go to File>New Catalog and choose a meaningful destination and name for the new catalog.
6. Go to File>Import from Catalog, navigate to the corrupted catalog you saved to the desktop, locate and highlight the .lrcat file and click “choose”.
7. Lightroom will present you with the familiar import dialogue box, be sure to select “Import photos at their current location” and click “Import”.

8. Lightroom will think for a while, then most likely give you an error message that reads something like “Lightroom was unable to successfully import the catalog” … Ignore this.
9. If the computer gods are smiling on you, you now have a new, non corrupt, almost fully functional catalog, complete with virtual copies and catalog sets.
10. Go through the new catalog and check for anything that may be missing. There will be some missing images, but in my case, three or four missing virtual copies pales in comparison to having to go back and re-create hundreds of virtual copies.

If any of you have experienced or are experiencing a similar problem, and have a similar workflow of always “Importing photos at their current location”, I hope you find this material helpful, and that it helps you recover your database!

Text © Jonathan Kingston 2007