Transparency in Images

Facebooktwitterlinkedin

Today’s Question: Regarding the PNG image format: What does “supports transparency in the image” mean?

Tim’s Quick Answer: Transparency in a PNG (Portable Network Graphics) image means that in certain situations when you place a PNG image against a background, that background will show through in the transparent areas of the image. JPEG images, by contrast, do not support this transparency feature.

More Detail: Transparency can be used in a variety of situations to isolate an area or element within an image and allow another background to show through. This is similar in concept to the creation of composite images in Photoshop, where you use a layer mask on an image layer to hide specific areas, and allow underlying layers to show through in the masked out areas.

With a PNG image, it is possible to preserve transparency in a final derivative image that you can then share in a variety of ways while preserving that transparency. For example, let’s assume you have “cut out” the key subject in a photo, hiding the rest of the image from view through the use of a layer mask in Photoshop. If there are no other image layers below the masked layer, then there will be no pixels in the areas that are masked out. You can save that masked image as a PNG image with the option enabled to preserve transparency.

You can then place that image onto a web page, into a slide show, in a document using a word processor or other software for creating documents, among other options. With any software that supports transparency in PNG images, the background onto which you’ve placed the image will show through the masked out (transparent) areas, so that the isolated subject in the photo will be set against that background.

So, for example, if you have a background texture on a web page or slideshow presentation, the isolated subject in your PNG image will allow that background texture to show through in the transparent areas of the image. Had transparency not been supported, those areas around your key subject would have been white instead, which would not blend in with the background texture where you had placed the image.

Disabling Sharpening

Facebooktwitterlinkedin

Today’s Question: I have been using Lightroom CC for a couple years and I am just discovering that Lightroom automatically sharpens every image. I discovered this in my efforts to use Topaz Denoise. How do I disable this auto sharpening?

Tim’s Quick Answer: You can disable sharpening for images that are not yet in your Lightroom catalog by changing the default settings in the Develop module or by applying a preset during import. If you want to apply that change to existing images you will need to synchronize only the Sharpening adjustments across all photos in your catalog.

More Detail: Lightroom applies a small degree of sharpening by default to all photos you import into your catalog. It is possible, however, to change the default settings for the Develop module or to synchronize specific settings (such as to remove sharpening) across a large number of photos.

For example, you could select all of the photos in a given folder (or all photos in your Lightroom catalog) in order to synchronize settings for those photos. In the Develop module you will still be working with a single active image, even though you have selected multiple photos. To reset the sharpening for the current photo, simply set the Amount value under Sharpening in the Detail section of the right panel to a value of zero.

Next, click the “Sync” button at the bottom of the right panel to bring up the Synchronize Settings dialog. Click the “Check None” button to clear all of the checkboxes. Then turn on the Process Version and the Sharpening checkboxes, and click the Synchronize button. This will synchronize the updated sharpening settings (with no sharpening being applied) for all of the selected photos.

If you want to change the default settings for all new images you import into Lightroom, you can change those defaults or employ a preset during import. I recommend using a preset during import because this provides a little more flexibility and makes it easier to be consistent with all images.

So, for example, you could create a new preset that includes only the settings you want to update during import. That might include the removal of chromatic aberrations and the application of a lens-based profile, as well as removing sharpening. Start with a “sample” image, and then click the Reset button at the bottom of the right panel in the Develop module to reset to the default settings. Adjust the settings you want to apply to all images, such as changing the sharpening to remove this effect.

When you have the settings adjusted as desired, you can click the “plus” (+) button to the right of the Presets header on the left panel in the Develop module. Name the new preset, and click “Check None” to deselect all adjustment options. Then turn on the checkbox for all adjustment options you want to include as part of this preset.

When you import photos, select this saved preset from the Develop Settings popup in the Apply During Import section of the right panel. This will enable you to apply specific settings for images you import into Lightroom. Note that this will also become the default option for all future import operations, since the settings are mostly “sticky” within the Import dialog.

Bridge to Lightroom

Facebooktwitterlinkedin

Today’s Question: How can you move an extensive list of folders from Adobe Bridge to Lightroom and maintain the folder structure?

Tim’s Quick Answer: You can simply import your entire folder structure using the “Add” option in Lightroom’s import feature, and your complete existing folder structure will be retained and reflected within your Lightroom catalog.

More Detail: Many photographers have a misconception about the Lightroom catalog and the impact of that catalog on an existing folder structure. Put simply, the Lightroom catalog references your existing file and folder structure, so that any folder structure you’ve been using to manage your photos thus far can still be used if you choose to transition to Lightroom.

When you are importing photos from an existing folder structure, you can simply select as the source of your import the top-level folder for that storage structure. For example, this might be the “Pictures” folder in your operating system or an external hard drive dedicated to the storage of photos.

By enabling the “Include Subfolders” option at the top of the left panel in the Import dialog, and making use of the “Add” option at the top-center of the dialog, you can add your entire existing collection of photos into your Lightroom catalog.

For subsequent import operations, you can use the Copy option to, for example, download images from the media cards from your camera to the storage location that contains your photos. You can also create a folder as part of that process, based on the folder strategy you’ve already defined for managing your photos.

To learn more about understanding Lightroom, defining a workflow that best suits your needs, and much more, take a look at my “Cleaning Up Your Mess in Lightroom” bundle. This bundle is useful even for photographers who haven’t made a mess in Lightroom and want to be sure they avoid doing so. You can get a discount on this full bundle of video courses by following this link:

http://timgrey.me/messatg

Access to Dehaze

Facebooktwitterlinkedin

Today’s Question: Is there a way to rectify the lack of the Dehaze slider in Lightroom 6?

Tim’s Quick Answer: You can access Dehaze within Lightroom 6 by first creating a preset (or series of presets) for the Dehaze adjustment in Lightroom CC and then installing the Dehaze preset(s) in Lightroom 6.

More Detail: The Dehaze adjustment in Lightroom CC is ostensibly not available in the standalone (non-subscription) version of Lightroom 6. However, through the use of presets you can access Dehaze in Lightroom 6.

The first step is to create one or more presets in Lightroom CC that include only the Dehaze adjustment. For example, you might create a preset with the Dehaze setting at various values, perhaps in 20% increments. For each variation you want for the Dehaze adjustment, create a new preset by clicking the plus symbol (+) to the right of the Presets header on the left panel in the Develop module.

In the “New Develop Preset” dialog enter a name for the preset (such as “Dehaze 20”) that will be meaningful. Then click the “Check None” button at the bottom-left of the dialog, and turn on only the “Dehaze” checkbox in the Effects section of controls. Note that the Process Version checkbox will remain enabled, and you want to keep that checkbox turned on. Click Create to create the actual preset, and repeat for as many variations as you want to have.

Next, export the Dehaze presets by right-clicking on each and choosing “Export” from the popup menu. Save the preset you’re exporting with the same name you used for the preset itself, in a location that is convenient for transferring these files later. I recommend saving the various exported presets in a folder called “Dehaze” that is in turn located on the Desktop in your operating system.

Then follow these steps to make these Dehaze presets available in Lightroom 6:

1) Go to the Preferences dialog by selecting Preferences from the Edit (Windows) or Lightroom (Macintosh) menu on the menu bar.

2) Go to the Presets tab in the Preferences dialog.

3) Click the “Show Lightroom Presets Folder” button to open a window in your operating system that will show the Lightroom folder where presets are stored.

4) Close the Preferences dialog and quit out of Lightroom.

5) In the window that opened when you clicked the “Show Lightroom Presets Folder”, open the “Lightroom” folder, and then open the “Develop Presets” folder.

6) Copy the folder containing the exported Develop presets into the “Develop Presets” folder opened above.

7) Launch Lightroom.

At that point you will find a “Dehaze” folder in the Presets section of the left panel in the Develop module. You can click on the presets by name to apply Dehaze at a given percentage strength based on the presets that were originally exported from Lightroom CC.

Locating Source Folder

Facebooktwitterlinkedin

Today’s Question: When I do a Bridge search for a file number (or other image attributes) is there a way to identify what folder the image file was found in?

Tim’s Quick Answer: Yes, you can right-click on an image in your search results within Adobe Bridge and choose “Reveal in Bridge” to automatically navigate to the folder where the source file is located.

More Detail: This question was presented in response to a question about a similar feature that is available in Adobe Lightroom. In short, when you use a filter or search feature to locate a specific photo, it isn’t always immediately obvious which folder the image is actually located in.

There are two basic options available in both Adobe Bridge and Lightroom that enable you to navigate to the source folder after locating an image through a filter or search.

The first is to reveal the source folder within the application. In Adobe Bridge you can do so by right-clicking on the image you located with a search, and then choose “Reveal in Bridge” from the popup menu that appears. In the Folders panel the source folder will be highlighted, with the image you selected highlighted within the Content panel. In Adobe Lightroom you can accomplish the same basic task by right-clicking on an image and choosing “Go to Folder in Library” from the popup menu.

In both Adobe Bridge and Adobe Lightroom you can also open up a window from your operating system that reveals the folder where the image is contained. For this option you can right-click on the image and then choose “Reveal in Finder” for Bridge or “Show in Finder” for Lightroom if you are a Macintosh user, or “Reveal in Explorer” for Bridge or “Show in Explorer” for Lightroom if you are a Windows user. This will open a window in your operating system revealing the applicable folder for the image you selected.

Converting to 8-Bit

Facebooktwitterlinkedin

Today’s Question: After working the master file in 16-bit, is it OK to convert the master file to 8-bit right before saving the master file as a Photoshop PSD?

Tim’s Quick Answer: My answer here would be “no”, in part because it would be necessary to also flatten the master image if you are going to convert it to 8-bit per channel mode.

More Detail: When you convert an image from 16-bit per channel mode to 8-bit per channel mode in Photoshop, the adjustments are also “scaled” to the 8-bit per channel mode. In other words, you lose the benefit of having worked in the 16-bit per channel mode in the first place.

Therefore, if you need to convert a layered image from 16-bits to 8-bits per channel, it is important to flatten the image.

As any photographer who has been reading my work for any length of time can probably appreciate, I prefer to retain as much information as possible in my master image file. That means I prefer not to flatten a layered master image in Photoshop, and I prefer to keep that master image in the 16-bit per channel mode.

If you want to convert a master image to the 8-bit per channel mode in order to reduce the file size, you would also want to flatten the image first to retain the benefit of the original adjustments you applied in the 16-bit per channel mode.

So, if you’re comfortable both flattening the master image and converting the result to the 8-bit per channel mode, then you can convert. If you’re not comfortable flattening the master image I would advocate for keeping that master image in the 16-bit per channel mode as well.

Pen Pressure Fail

Facebooktwitterlinkedin

Today’s Question: I’ve been using the Wacom tablet with Photoshop CS6 and the pen responds to pressure.  With the download of Photoshop CC, there is not response to pressure. I may as well be using a mouse. Is there a fix?

Tim’s Quick Answer: You can either “force” the use of pen pressure to affect size or adjust the brush preset settings within the Brush panel in order to resolve this issue.

More Detail: With the brush-based tools within Photoshop that support pen pressure, there is a button on the options bar that enables you to force the use of the stylus pressure to adjust brush size. You’ll find this button at the far right of the Options bar for tools such as the Brush tool and the Clone Stamp tool.

If you don’t want to turn on this “universal” setting, you can also adjust the settings for individual brush presets using the Brush panel. For example, on the Shape Dynamics tab of the Brush panel you can set the Control popup for Size Jitter to “Pen Pressure”. This setting can be adjusted for each individual preset in the Brush panel, so if you want to always use the stylus pen for adjusting the brush size, the “universal” setting on the Options bar may be your better approach.

Rotating the Crop

Facebooktwitterlinkedin

Today’s Question: I often need to switch from landscape to portrait in the crop tool in Lightroom [or Photoshop]. Is there an easy quick way to do that?

Tim’s Quick Answer: Yes! You can rotate the orientation of the crop box in Lightroom or Adobe Camera Raw by pressing the “X” key on the keyboard.

More Detail: Many photographers (myself included) find that they periodically want to rotate the crop box by 90 degrees, such as to rotate a horizontal crop box to a vertical orientation.

When working with the Crop tool within either Lightroom or Adobe Camera Raw, pressing the “X” key on the keyboard will rotate the orientation of the crop box between landscape and portrait. If you have selected a fixed aspect ratio for that crop, that aspect ratio will be retained. If you have not selected a fixed aspect ratio, whatever aspect ratio your current custom crop represents will be retained.

PNG File Size

Facebooktwitterlinkedin

Today’s Question: Occasionally, I attach a screen grab to an email, usually PNGs directly from my Mac’s screen-grab commands. In one example the PNG’s file size is over 860KB versus the JPG version at 208KB. Are PNGs always so big, at about four times the size of equivalent JPGs?

Tim’s Quick Answer: PNG (Portable Network Graphics) files will generally be considerably larger than JPEG (Joint Photographic Experts Group) images, because PNG images use lossless compression compared to lossy compression for JPEGs. The specific results will vary depending on the image in question, but when file size is the priority the JPEG format is preferred over PNG.

More Detail: When sharing images, the JPEG file format is a popular option because it enables you to achieve relatively small file sizes. This small file size is achieved due to lossy compression, meaning some degree of image quality may be lost even at a high quality setting.

By comparison, the PNG file format uses lossless compression. As a result, image quality is preserved at the cost of a larger file size.

Of course, at a high quality setting the JPEG image will generally appear to have quality that is nearly the same as the same image saved as a PNG file. Therefore, the JPEG file format is generally superior for sharing images where file size is a concern, such as for online sharing.

In theory the PNG format would be preferred when image quality is the priority. However, in those cases it might also make sense to instead use the TIFF file format. The main reason I consider the PNG format to be important is that it supports transparency in the image. This isn’t generally a necessity for a photographic workflow, but for certain uses (such as in digital slideshows, on web pages, or in videos) that feature can be helpful.

Curve Direction

Facebooktwitterlinkedin

Today’s Question: When a Curves adjustment is used to increase or decrease brightness in an image, some photographers drag the curve center point at a roughly 45 degree angle toward the top left to increase brightness or toward the bottom right to decrease brightness. Other photographers drag the center point vertically toward the top to increase brightness or vertically toward the bottom to decrease brightness. And the arrow keys also facilitate fine adjustment using this approach. The resulting tone curves are plainly different with each approach. Which is the best approach for overall image brightness adjustment?

Tim’s Quick Answer: There isn’t a single “correct” direction to drag an anchor point with the Curves adjustment. Rather, what is important is the specific relationship you’re defining between the “before” and “after” value for tonality. The optimal result will vary based on the specific image you’re working on.

More Detail: If you drag an anchor point directly upward (or downward) at the precise center of the curve, you will be applying an equal adjustment to the highlights and shadows in the image. If the anchor point is dragged out at a 45-degree angle toward the top-left, you will have a stronger effect on the highlights than on the shadows.

What ultimately matters here is the shape of the curve and the effect you want to have on the image. Keep in mind that what you’re altering with the curve is the relationship between the “before” and “after” values within the image. How you adjust the shape of the curve depends on how you want to adjust the tonal values in bright versus dark areas of the image.

It is also worth keeping in mind that in many (if not most) cases you will want to add more than one anchor point for the Curves adjustment. This enables you to have a different effect in highlight areas versus shadow areas of the image, for example. In some cases you might want to lighten the shadows and darken the highlights, while in other cases you might want to darken the shadows and lighten the highlights. And of course with some images you might want to only lighten or darken, though with an emphasis on specific tonal ranges.

So again, it is important to consider the shape of the curve for a Curves adjustment based on how you want to alter the appearance of the specific photo you’re working on.