Prioritizing Shutter Speed

Today’s Question: I saw your (very nice) photo of a crop duster, and wonder how you go about making sure the propeller is actually shown to be moving rather than being “frozen” by a fast shutter speed. Do you just stop the lens down to the smallest aperture?

Tim’s Quick Answer: Photographing propeller-driven aircraft is a perfect example of a rare case when I will actually use shutter priority (or time value) exposure mode. I determine an appropriate shutter speed for the subject, and set that as a fixed exposure setting in shutter priority mode, ensuring a degree of blur for the propeller in each photo.

More Detail: In the case of the photo you are referring to, the crop duster is powered by a turboprop engine that turns the propeller at a relative fast rate. Therefore, a shutter speed of no faster than about 1/250th of a second or so will ensure a small amount of motion blur for the propeller, while still providing a shutter speed that is fast enough to help achieve a photo where the airplane actually appears sharp.

For those who didn’t see the photo referenced in the question, by the way, you can view it on my 500px page here:

https://500px.com/photo/112385163/crop-duster-spraying-in-palouse-by-tim-grey

When you are using shutter priority mode (as opposed to aperture priority mode) there is an increased risk of “running out” of appropriate exposure settings. In other words, there is a risk that the shutter speed you have set will require an aperture that goes beyond what your lens can actually achieve. On a bright sunny day that might mean even with the lens fully stopped down the exposure is too bright, or that even with the aperture fully open the exposure is too dark.

Because of this issue, when I set the camera to shutter priority mode I will hold the shutter release button halfway down to enable the meter on the camera, and then point the lens at various areas within the scene before me, being sure to check the brightest and darkest areas to confirm that an appropriate aperture is available.

If the subject will remain under relatively fixed lighting conditions, I might also use the manual exposure mode with specific exposure settings that work for the subject. However, when photographing aircraft it is very likely that the lighting conditions will change on the subject. For example, in some cases the aircraft may be lit from the front, while in other cases it may be backlit. In these types of situations I find that shutter priority mode helps ensure more consistent results, though it may also be necessary to apply some degree of exposure compensation.

Again, the key to photographing propeller-driven aircraft is to use the fastest shutter speed you can (generally speaking) that will still ensure at least some degree of motion blur for the propeller. The specific shutter speed will vary based on the rate at which the propeller is spinning, but in most cases shutter speeds in a range from about 1/125th of a second to about 1/350th of a second will produce excellent results.

Posted in Ask Tim Grey | Comments Off on Prioritizing Shutter Speed

Inaccurate Ruler in Photoshop

Today’s Question: In Photoshop I drew a grid  made up of one-inch squares on a transparent layer. I use it for my drawings placing the grid over a photo. However, when I place my ruler on the monitor screen to see if the squares are one inch, I find they are not and no matter what I do (fit screen, print size, actual pixels, zooming in and out), the squares are never one inch. In other words, the monitor screen inch does not match my ruler inch.

Tim’s Quick Answer: The solution here is to set the Screen Resolution in the Preferences dialog for Photoshop to the true pixel per inch resolution of your monitor display, and then make use of the Print Size display option from the View menu.

More Detail: By default Photoshop assumes a display resolution of 72 pixels per inch. That does not match the vast majority of monitor displays in use today. To calculate your actual pixel per inch (ppi) resolution, you need to know what pixel dimensions you have set as the resolution for your monitor display. You can then measure the horizontal display size for your monitor, and calculate the actual pixel per inch resolution.

For example, let’s assume a display that is operating at 1920 by 1080 pixels (full high definition resolution). Let’s further assume the width of the actual display area for the monitor is 14 inches. With 1920 pixels across and a width of 14 inches, there are 137 pixels per inch across the display.

To set the resolution you’ve calculated for the display in Photoshop, you’ll need to first bring up the Preferences dialog. To do so, choose Photoshop > Preferences > Units & Rulers on the Macintosh version of Photoshop, or Edit > Preferences > Units & Rulers on the Windows version of Photoshop. In the Units section, set the value for Screen Resolution to the number you calculated (137 in the example above) and set the popup to the unit of measure you used (“Pixels/Inch” in this example). Then click OK to close the Preferences dialog.

With this setting established, when you choose View > Print Size from the menu in Photoshop, the image will be resized based on the pixel per inch resolution so that one inch on Photoshop’s ruler display (View > Rulers from the menu) will represent one inch on your monitor, and the size of the image will match what you can expect for the image if it is printed at the current resolution setting for the image.

Posted in Ask Tim Grey | Comments Off on Inaccurate Ruler in Photoshop

Viewing Coordinates

Today’s Question: In this past Friday’s “Ask Tim Grey” you made reference to the ability to view GPS coordinates in metadata. If I’m not using an application like Lightroom that allows me to view my photos on the map, how can I make use of the GPS coordinates to know where I captured the photo?

Tim’s Quick Answer: The GPS coordinates stored in metadata for camera’s that include a GPS receiver are latitude and longitude coordinates, and you can very easily view a specific location on a map using a service such as Google Maps by copying and pasting the coordinates into the search for the map.

More Detail: Among other options, you can use Google Maps to view the location for the GPS coordinates stored in metadata for an image. Simply select the coordinates from the GPS field in metadata, and then visit the Google Maps website at http://maps.google.com. Paste the GPS coordinates into the search field and press Enter/Return on the keyboard, and the map will be centered on the location represented by the coordinates you copied from metadata.

To be sure, it is much simpler to browse an entire collection of photos on the map using applications such as Lightroom or the Photoshop Elements Organizer. But the GPS coordinates saved to metadata when you are using a camera with a built-in GPS receiver can be used in a variety ways to determine the specific location where you captured a given photo.

Posted in Ask Tim Grey | Comments Off on Viewing Coordinates

Renaming a Catalog

Today’s Question: I just updated my Adobe CC for Photographers to the 2015 version. In the process of doing that my Lightroom catalog’s name was changed from “LR-5” to “LR-5-2”. Is there some simple way for me to change it to “LR-6”? I want to do that since I plan to use Lightroom for some time to come and I do not want to eventually get some future catalog named “LR-5-2-2” and so forth. Also any thoughts on how to name Lightroom catalogs?

Tim’s Quick Answer: You can most certainly rename your Lightroom catalog, but that won’t actually prevent future versions of Lightroom from modifying that name when a catalog is upgraded to a new version.

More Detail: When you upgrade to a new “major” version of Lightroom, your catalog from an earlier version of Lightroom must be upgraded to the new catalog format. This is necessary to support new features and adjustments, among other changes that may have been made to the catalog structure. During this process, rather than modifying your existing catalog, the new version of Lightroom will create a new catalog based on the existing catalog, with a new name for that catalog.

If you want to rename your catalog the first step is to know exactly where your catalog is. You can find this information in the Catalog Settings dialog, which can be accessed by choosing “Catalog Settings” from the Lightroom menu on the Macintosh version of Lightroom or the Edit menu on the Windows Version of Lightroom.

In the Catalog Settings dialog go to the General tab and click the Show button. This will open a window in your operating system showing the location of the folder containing your catalog files, with that folder highlighted.

Before renaming your catalog, you need to close Lightroom. So switch back to Lightroom and quit the application, then return to the window with your catalog folder. Double-click to open the catalog folder, where you will find the files that represent your Lightroom catalog.

You’ll want to start with the file that has the “.lrcat” filename extension, as this is the primary catalog file. Right-click on this file and choose the Rename option, then type a new name. Be sure to keep the “.lrcat” filename extension unchanged as part of the new filename.

You then need to use the new filename as the base filename for the remaining files, keeping the “extra” portion of the filename exactly as it is. You will have, for example, a file that includes the word “Previews” as part of the base filename, with a filename extension of “.lrdata”.

For example, if you renamed the catalog to “My Lightroom Catalog.lrcat”, you would change the Previews filename to “My Lightroom Catalog Previews.lrdata”.

Once you have renamed the files with the same base filename, you can re-launch Lightroom. By default Lightroom will attempt to open the existing catalog that you just renamed, but of course will not be able to find that catalog because the filename has been changed. In the dialog that appears you can click the “Choose a Different Catalog” button to bring up a dialog where you can once again click the “Choose a Different Catalog” button so you can navigate to the location where the catalog is stored and select the “lrcat” file. Lightroom can then open that renamed catalog, and you can continue working normally.

Note that the process of renaming a catalog in Lightroom is also covered in Lesson 12 of the Lightroom video course “Resolving Organizational Challenges”, available in the GreyLearning video training library. If you are a GreyLearning subscriber, you can view this lesson to see the subject of today’s answer presented in video. And if you’re not already a subscriber, you can get details about accessing all of the courses available in the GreyLearning library here:

http://greylearning.com/

Posted in Ask Tim Grey | Comments Off on Renaming a Catalog

GPS Options

Today’s Question: My SLR doesn’t include GPS, but I would like to be able to keep track of where I captured my photos without marking spots on a printed map. Is there a good solution, or should I just “upgrade” to a camera that includes GPS capabilities?

Tim’s Quick Answer: There are a few options available to you. Obviously you could simply purchase an SLR that includes a GPS receiver. You could also purchase an accessory GPS receiver for your camera if your camera supports this option. And another option is to use a GPS-enabled device (such as your smartphone) to capture reference photos, which I refer to as “location snapshots”.

More Detail: Having GPS built into your camera is most certainly a very convenient solution for photographers (such as myself) who frequently want to be able to keep track of the location where they captured their photos. With the GPS receiver turned on you are most certainly going to cause the battery to discharge more quickly. Therefore, you need to determine whether the location information is worth the reduction in battery life. For me the decision is easy, because I tend to value the location information for my photos. But this is a decision each photographer will need to make based on how they prioritize that information.

For those who have a camera that supports accessory GPS receivers, this provides another solution. These devices generally attach to the flash hot shoe, and then plug into the camera to provide GPS coordinates that are automatically added to the metadata for each capture.

With both of the above options you can then view the GPS coordinates in metadata, or use an application such as Lightroom to plot your photos on the map based on those GPS coordinates.

You can also use another device to track locations for your photos. One solution that works great in many situations is to create what I refer to as “location snapshots”. This was the subject of the article titled “Location Snapshots” in the August 2012 issue of Pixology magazine (http://www.pixologymag.com). With this approach you use a device (such as a smartphone) to capture a reference photo that contains GPS coordinates in the metadata, and then use that photo as a reference for adding (or simply reviewing) location information for your other photos.

In addition, you can use a GPS device (such as a smartphone) to record a track log, and then use software such as Lightroom to synchronize the track log with the photos, adding GPS coordinates to the photos in a relatively automated way.

As you can see there are a variety of solutions for adding location information to your photos. Choosing a solution that works best for you is a matter of understanding the options that are available and comparing those options based on your specific workflow priorities.

Posted in Ask Tim Grey | Comments Off on GPS Options

File Size Confusion

Today’s Question: I am limited to an image size of 500 KB when uploading for my blog. I am finding images that appear to be under the limit but are huge. One image shows as 465 KB on my disk but when I open it in Photoshop it is over 2000 pixels wide and around 8.7 MB in size. My online form sees the 465 KB, accepts it and then stalls.

Tim’s Quick Answer: In this case the confusion is simply a matter of one way that Photoshop reports the size for an image. The actual file size you’re seeing outside of Photoshop is accurate. The size reported inside Photoshop doesn’t relate to the actual size of the file on the hard drive.

More Detail: When you are limited to a particular file size for an upload, it is the actual size of the file on the hard drive that is the issue. It is important to keep in mind, however, that sometimes that file size is reported in different ways. In other words, there are situations where the file size is below the limit, but the website you are trying to upload to calculates the size differently. I do realize that this seems odd (and it is odd), but this is an issue that we run into at times. (For those interested in the more specific details, as an example one megabyte is sometimes considered to be 1,000 kilobytes and sometimes considered to be 1,024 kilobytes, depending on context.)

When you open an image in Photoshop, the status bar will by default show you the document sizes. This relates not to the actual size of a file stored on your hard drive but rather to the amount of data in the image file itself. This is presented as two numbers. The first number can be thought of as the size the image file would be if you saved the image as a TIFF image without any compression applied, and with all layers flattened into a single layer. The second number represents the image if it is saved as a TIFF image with no compression, but with all layers preserved.

In other words, when it comes to the size of a file on the hard drive, you can largely ignore the document sizes presented in Photoshop, especially if the image will be saved as a JPEG. But it is also important to keep in mind that if the size of that saved JPEG is close to the limit for an upload, it is still possible the upload will fail. And, of course, there are other reasons beyond file size that an upload might fail.

Posted in Ask Tim Grey | Comments Off on File Size Confusion

Dehaze Requires Subscription

Today’s Question: My Lightroom 6 does not have the Dehaze adjustment. Is it only on the Creative Cloud version of Lightroom?

Tim’s Quick Answer: Yes, it is true that the new (and wonderful) Dehaze adjustment in the latest update to Lightroom is only available with the Creative Cloud (subscription) version of Lightroom and not with the standalone (non-subscription) version of Lightroom.

More Detail: If you want to gain access to the new Dehaze adjustment, you will need to sign up for a Creative Cloud subscription, since the new adjustment is only included in the Creative Cloud version of Lightroom (version 2015.1) and not the standalone update (version 6.1).

There is an apparent workaround that I’ve not tested, involving the creation of a preset that includes Dehaze (using a computer running Lightroom CC) and then installing that preset in Lightroom 6.1. But with the Creative Cloud 2015 (aka version 6) update to Lightroom, only Creative Cloud subscribers will have access to new features. Those who opt for the standalone (non-subscription) version of Lightroom 6 will get access to updates for support of new RAW capture formats and bug fixes, but not new features until the next major release.

Posted in Ask Tim Grey | Comments Off on Dehaze Requires Subscription

Panning within a Photo

Today’s Question: Every time I retouch a picture in Lightroom with the cloning/healing tool at a 200% zoom view, I can’t find an easy way to pan around the photo. I always have to use the Navigator on the left panel, which I usually hide while retouching to see more of the picture. Is there an easier way?

Tim’s Quick Answer: There is indeed an easier way! Simply hold the Spacebar key on the keyboard while working with the Spot Removal tool in Lightroom, and you will have temporary access to the Hand tool for panning around the photo. While holding the Spacebar key on the keyboard, you can then simply click-and-drag on the image to pan around as needed.

More Detail: This same process works in Photoshop, Adobe Camera Raw, and Lightroom. The Spacebar key on the keyboard serves as a shortcut to the Hand tool, which is a tool that allows you to pan around an image when you have zoomed in beyond the available space within the interface.

In Photoshop the Spacebar keyboard shortcut has a bit more utility than in Lightroom, because when you aren’t working with a tool such as the Spot Removal tool the Spacebar keyboard shortcut will toggle the zoom setting for the image. But when working with image cleanup the Spacebar keyboard shortcut is very helpful, allowing you to pan around to check for additional blemishes as you work to clean up a photo.

Posted in Ask Tim Grey | Comments Off on Panning within a Photo

New Tool for Haze

Today’s Question: Can you explain how and when to use the new “Dehaze” control in Lightroom CC (2015)?

Tim’s Quick Answer: The new “Dehaze” adjustment in Lightroom CC 2015.1 is quite remarkable, and as the name implies can be used to dramatically reduce the appearance of haze in images captured under hazy atmospheric conditions. Increasing the value will significantly reduce the appearance of haze in the photo, and reducing the value will increase the appearance of haze in the photo.

More Detail: I had previously referred to the Clarity adjustment in Lightroom’s Develop module as the “haze buster”, but I will no longer refer to it this way now that the Dehaze adjustment has been added to Lightroom. While the Clarity adjustment can certainly help reduce the appearance of haze in a photo, it is really focused on improving mid-tone contrast.

The “Dehaze” adjustment, on the other hand, is specifically focused on reducing the appearance of haze in a photo. Therefore, we can now simply think of the Clarity adjustment as being focused on enhancing texture and detail in a photo, while the Dehaze adjustment allows you to dramatically reduce the appearance of atmospheric haze in a photo.

The results of Dehaze are, in my experience, simply remarkable. If you are a Facebook user, you can see a sample image that shows the original photo, the effect of Clarity, and the effect of Dehaze. You’ll find that image on the wall for my “Tim Grey Photo and Imaging” page here:

https://www.facebook.com/timgreyphoto

The Dehaze adjustment is found in the Effects set of controls. To reduce the appearance of haze in a photo simply drag the Amount slider for Dehaze toward the right. You can adjust the setting based on your own preference, without much risk of any serious problems in the photo. The only thing to keep an eye on is an overly dramatic appearance for the photo, with strong shadows and exaggerated contrast.

With a little practice you’ll get a sense for how much of a Dehaze adjustment might be too much for an image. In some respects the issue here is similar to the processing of high dynamic range (HDR) images, where it is generally preferred to avoid the appearance of “over-processing” for the photo. But used with a degree of self-control, the Dehaze adjustment can create a dramatic improvement in many photos.

Posted in Ask Tim Grey | Comments Off on New Tool for Haze

Sun Spots

Today’s Question: I was inspired by your recent photo “Sunrise in the Palouse”, and went out to try capturing photos that include the sun in the frame. I was able to get the exposure pretty good (setting a minus exposure compensation), but ended up with lots of somewhat bright (but not colored) circles in the photo. Is that lens flare of some sort? What can I do to avoid these circles?

Tim’s Quick Answer: Your description sounds like the effect from having dust or other debris on the front element of your lens. When including the sun in the frame (or nearly in the frame) it is critically important to clean the lens. I recommend making use of a lens cloth, brush, blower, or similar device to clean the front of the lens frequently when photographing with the sun in (or near) the frame.

More Detail: Fortunately, in most cases it is relatively easy to clean these spots after the capture, especially if the spots appear in an area of open sky. However, because the sun will cause the dust or other contaminants on the front lens element to “glow” with light, then can interfere with textures and details within the photo. Therefore, it is important to try to avoid this issue in the first place.

I make a point of cleaning the front lens element once I’m ready to capture my shot whenever I’m including the sun in (or near) the frame. I’ll then keep an eye on the front lens element, especially when I’m in a dusty area, and clean the lens as often as is needed (or more often than that!).

The photo referenced in today’s question can be found on my 500px page here:

https://500px.com/photo/111950955/sunrise-in-the-palouse-by-tim-grey

In this case I was working before (and during) sunrise in a very dusty area, and ended up with some of the spots referred to in today’s question even though I had cleaned the lens a few frames before the image seen above was captured. Even though I was trying to be careful, I didn’t get the front lens element completely clean (or more dust accumulated after I cleaned the lens), so I had a bit of cleanup work to do after the capture.

If you are very careful to keep the front lens element clean, you’ll able to minimize the effect of these glowing circles, which can be very distracting in the photo. Lens flare, of course, can’t be completely avoided if you are including the sun in the frame. But even that can often be cleaned up or minimized in post-processing.

Posted in Ask Tim Grey | Comments Off on Sun Spots