Bit Depth Importance

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Today’s Question: Is the ability to work in 16-bit per channel mode important enough to justify subscribing to the Adobe Creative Cloud in order to get Photoshop, or is 8-bit per channel (and therefore Photoshop Elements) adequate?

Tim’s Quick Answer: I would not consider 16-bit per channel mode to be reason enough to opt for Photoshop CC over Photoshop Elements, keeping in mind that Photoshop Elements does provide some support for working with 16-bit per channel images.

More Detail: Photoshop Elements actually does support working with 16-bit per channel images, but only on a very limited basis. For example, you can’t use adjustment layers with 16-bit per channel images in Photoshop Elements, while Photoshop CC supports the majority of features for 16-bit per channel images.

Working in 16-bit per channel mode (as opposed to 8-bit per channel mode) is mostly important when you need to apply very strong adjustments to an image, especially for a black and white interpretation of a photo. For images that only require a modest degree of adjustment, the advantages of 16-bit per channel mode are relatively minor.

Because Photoshop Elements provides limited support for 16-bit per channel images, you can most certainly make use of those capabilities for images that require strong adjustments. You can convert a raw capture to 16-bit per channel mode using the version of Adobe Camera Raw that is included with Photoshop Elements. You can then perform key adjustments (such as using Levels to refine overall tonality and color balance) directly on the image, since adjustment layers are not supported for 16-bit per channel images in Photoshop Elements.

Once you’ve applied the most important adjustments directly to the image in 16-bit per channel mode, you can choose Image > Mode > 8 Bits/Channel from the menu to convert the image to 8-bit per channel mode so you can continue using adjustment layers and layer masks to fine-tune the image.

In other words, if you don’t find any of the other features of the “full” version of Photoshop compelling, the expanded support for working with 16-bit per channel images isn’t something I would consider to be critical. Working with 16-bit per channel images in Photoshop Elements requires a workflow that does not use layers, but otherwise you still have considerable flexibility when working with these images. And again, images that were properly exposed and only require minor adjustments will not achieve a significant benefit by working in 16-bit per channel mode in the first place.

Stroke is Invisible

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Today’s Question: I am perplexed by my inability to apply a stroke around the edge of a photo. I’ve cropped the image, added a Stroke effect, made sure the Position option was set to “Inside”, but my stroke never appears on the photo. Do you have any idea what is going on here?!

Tim’s Quick Answer: I suspect this is an example of one of the challenges of applying a non-destructive crop. If you crop with the “Delete Cropped Pixels” checkbox turned off, you’ll likely find that adding a Stroke effect works normally again.

More Detail: The Crop tool includes an option to apply the crop non-destructively, meaning pixels you crop out of a photo will be hidden from view but not actually deleted.

This approach provides great flexibility in your workflow, but can also create some unintended side effects. One example is the issue reflected in today’s question. Since the Stroke effect applies at the edge of the image layer to which it is applied, if you apply a non-destructive crop it is possible for the Stroke effect to be added outside the visible area of the image.

When you crop with the “Delete Cropped Pixels” checkbox turned off, the pixels outside the crop box are not actually deleted, but rather hidden from view. In effect, the canvas size is reduced based on your crop dimensions, with the pixels outside the crop area simply being hidden from view.

If you want to add a Stroke effect to the edge of the final crop dimensions, you’ll need to apply a destructive crop to the image, meaning pixels outside the crop will be deleted. You can apply this crop by turning on the “Delete Cropped Pixels” checkbox with the Crop tool.

If you’ve already cropped the image with the “Delete Cropped Pixels” checkbox turned off, you can still apply a crop that will enable you to add a Stroke effect to the image. First, choose Edit > Select All from the menu to select the full visible image. Then choose Image > Crop from the menu to apply a destructive crop based on the full visible image. At this point, adding a Stroke effect will cause the stroke to be visible, provided you use the “Inside” setting for the Position popup, so that the Stroke effect will be added to the visible area of the image.

Unnecessary Bracketing

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Today’s Question: Is there any point in bracketing and blending in HDR [high dynamic range] if the total tonal range can be captured in a single exposure? In other words, if a single image histogram shows no clipping, is there any possible benefit to creating a bracketed HDR version?

Tim’s Quick Answer: There is the potential for reduced noise in shadow areas of the image if you bracket even when no clipping occurs in a single exposure. Thus, if you intend to interpret a photo to reveal significant shadow detail in the darkest areas of a scene, you may see improved results with an HDR image.

More Detail: High dynamic range (HDR) photography is often thought of simply as a way to retain detail in the full range of tonal values in a scene, from the darkest shadows to the brightest highlight areas. An additional benefit of HDR, however, is lower noise levels in the dark shadow areas of a photo. Put simply, blending exposures with HDR photography produces less noise in shadow areas compared to simply brightening up the shadows for a single capture.

Capturing a bracketed sequence of exposures to assemble into an HDR result can reduce the level of noise in the overall image, especially in shadow areas. In addition, extending your bracketing beyond the range of what is absolutely necessary can help reduce noise levels.

Using HDR when it isn’t necessarily critical, or expanding your bracket beyond the bare minimum for shadow detail, can both be helpful for reducing overall noise in the final image. As such, this approach would be most advantageous when you know you’ll want to reveal considerable shadow detail in the final image. If you’ll leave shadow areas relatively dark, that darkness can help hide noise that might otherwise be revealed.

Slow Online Backup

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Today’s Question: A few years ago I tried to backup my photo files to Carbonite. I set it up to start, and the next morning only a small percentage of the files had been transferred. I remember thinking that if I let the computer run 24/7 it would take a few weeks to back up over 350,000 RAW files. Should I try it again?

Tim’s Quick Answer: Yes, I think you should try again. While an online backup of a significant amount of data can indeed require considerable time, I have found that Carbonite may throttle your backup once you reach a certain volume of data. You might consider trying BackBlaze as an alternative online backup solution.

More Detail: Using an online backup service involves uploading your files to a server, which can mean uploading a significant amount of data potentially over a relatively slow connection. That can obviously require considerable time, especially for the initial backup of all of your existing data.

In some cases you may be able to ship a hard drive to an online backup service for your initial backup. Regardless, I recommend making use of a service that does not restrict your upload speeds, but instead is able to make use of your full connection speed. BackBlaze is one such service:

https://www.backblaze.com/cloud-backup/personal#af9pdk

Even without any throttling of your upload speed, your initial backup can require considerable time. For example, a somewhat typical high-speed Internet connection might offer an upload speed of 10 Mbps (megabits per second). That would translate to about ten days to upload one terabyte of data. In my case I have nearly six terabytes of photos, so my initial upload could take nearly two months.

Of course, your actual upload speed will depend on your Internet connection. If you are fortunate enough to have access to a connection that employs fiber optics, you could potentially have upload speeds as fast as 500 Mbps. That would reduce the time required to upload one terabyte to around four and a half hours, meaning I could conceptually upload my entire six terabytes of photo storage in a little more than one day.

It is important to keep in mind that after the initial backup is complete, much less time will be required to keep your online backup updated as you capture new photos and generate other additional data.

To be sure, there are limitations involved with an online backup. At the same time, a service such as BackBlaze can provide a cost-effective solution for having a backup stored at an offsite location. I always recommend using such a service only as a supplement to your local backup workflow, but it is indeed a workflow supplement that I recommend making use of.

Channel Count

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Today’s Question: You said “a CMYK file prepared for printed output would normally have four channels”. But how could a CMYK file have anything other than four channels, for cyan, magenta, yellow, and black?

Tim’s Quick Answer: While a CMYK file would normally contain four channels (cyan, magenta, yellow, and black), it is possible to add additional channels to provide “spot color” support when printing.

More Detail: Commercial CMYK offset press printing typically employs four inks, which are generally cyan, magenta, yellow, and black. This is similar to the typical ink sets used in photo inkjet printers, though today’s inkjet printers often include varying shades of each standard ink color, and sometimes include other colors altogether in order to expand the color gamut.

While offset press printing commonly involves four inks, that isn’t a fixed requirement. In cases where you don’t need a full color gamut, fewer than four inks might be used. And it is also possible to employ more than the standard four inks to supplement the color range available.

A typical four-ink CMYK offset press print job would be capable of producing a full range of colors such as would be found in a color photograph. But you can also print using inks that go far beyond the capabilities of CMYK inks. For example, gold ink might be added to print a golden signature on a photographic print. In some cases a “spot color” ink is actually a varnish that coats part (or all) of the print.

So while four inks are certainly standard for CMYK printing, it is also possible to change the number of inks used for specialty print jobs. This is one of the reasons that photographers may still want to consider offset printing for certain photo projects, even if they typically print their own photographic images under normal circumstances.

Advertised Bit Depth

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Today’s Question: I’m shopping for a flatbed scanner to scan some old family photos, and am confused about the bit depth specification. How does the 48-bit specification for the scanner relate to the 8-bit or 16-bit options available to me in Photoshop?

Tim’s Quick Answer: The specifications for many film and flatbed scanners list the combined bit depth for all three channels, rather than the per-channel bit depth often presented in software such as Photoshop. As such, 48-bit is actually the same as 16-bit per channel for a three-channel (RGB) image.

More Detail: In most software for processing images, the bit depth is presented as a per-channel value. This is in part because many users will need to work with images with a different number of channels, and thus a combined value for bit depth would be less clear. For example, a grayscale image could have a single channel, a typical color photo could contain three channels (for an RGB image), and a CMYK file prepared for printed output would normally have four channels.

So, if we assume a bit depth of 8-bit per channel, the grayscale image would have a total of 8 bits, the RGB image would have 24 bits (8 bits per channel times 3 channels) and the CMYK image would have 32 bits (8 bits per channel times 4 channels). This could obviously be confusing, since all of the images have the same per-channel bit depth.

Within software such as Photoshop, therefore, the bit depth is described based on the number of bits per channel, with typical images being either 8-bit per channel or 16-bit per channel.

Scanner specifications will often describe this bit depth based on the combined total of all channels, and based on an RGB image with three channels. Thus, a scanner that supports 8-bit per channel scanning would be described as a 24-bit scanner (8 bits per channel times 3 channels) and a scanner supporting 16-bit per channel scanning would be described as a 48-bit scanner (16 bits per channel times 3 channels).

Keep in mind that while image files are generally saved as 8-bit per channel or 16-bit per channel images, devices such as digital cameras and scanners might support other bit depths such as 12-bit per channel or 14-bit per channel. A scanner with 12- or 14-bit per channel scanning could then be described as a 36-bit or 42-bit scanner.

But again, the bottom line here is that scanner specifications often report the combined number of bits for all channels (typically based on a 3-channel RGB image), while imaging software generally presents the per-channel bit depth. As a result, a small amount of math may be required to translate bit depth support between scanners and software.

HDR in Photoshop

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Today’s Question: How do you recommend assembling a high dynamic range [HDR] image in Photoshop?

Tim’s Quick Answer: There are essentially three methods for assembling a high dynamic range (HDR) image in Photoshop. For a streamlined workflow that involves only using Photoshop, I recommend creating your HDR image in Adobe Camera Raw.

More Detail: A relatively recent update to Adobe Camera Raw added the ability to assemble HDR images directly within Camera Raw. It has also been possible for some time to create an HDR image within Photoshop. You might also consider the use of a third-party plug-in to create your HDR image.

Assembling an HDR image in Adobe Camera Raw is actually quite easy. You can start by opening multiple raw captures in Photoshop. As you may already be aware, when you open a raw capture in Photoshop, the Camera Raw dialog will appear so you can adjust the settings for processing the raw capture. When you open more than one raw capture, you will see a filmstrip in Camera Raw that enables you to select which image you want to work with at any given moment.

To create an HDR image you’ll first need to select all of the images on the filmstrip in Camera Raw. You can do so by clicking the popup menu button at the top-right of the filmstrip and choosing “Select All” from the popup menu that appears. To then initiate the process of assembling the HDR image, click the same popup menu button and choose “Merge to HDR” from the menu.

In the dialog that appears, I recommend turning on the “Align Images” checkbox as well as the “Auto Tone” checkbox. The first will help ensure the multiple images you are merging into an HDR will be properly aligned, and the second applies an initial set of adjustments to the resulting image, which you can then fine-tune.

If there had been any movement among elements in the frame when you captured your bracketed exposures, you can choose “Low”, “Medium”, or “High” from the Deghost popup. If you are going to apply ghost reduction to the image, I recommend turning on the “Show Overlay” checkbox so you can see where the deghosting effect will be applied. Choose the setting from the Deghost popup that results in an overlay only over the areas of the image where movement would have occurred.

You can then click the “Merge” button, and Camera Raw will assemble your HDR image. You’ll need to choose where to save the actual HDR result, and then the HDR image will appear within Camera Raw. At this point you can fine-tune all of the adjustments within Camera Raw to interpret the final image. Clicking the “Open Image” button will then cause the result to be opened in Photoshop for additional work, or you can instead click the “Done” button to save the updates without opening the final HDR image in Photoshop.

It is worth noting that there are a variety of third-party tools available for creating HDR images from Photoshop (or as a stand-alone application). In addition, Lightroom Classic provides the same ability to assemble and adjust an HDR image as is possible from Camera Raw. That said, using Camera Raw to assemble and apply adjustments to and HDR image can provide excellent results with a relatively streamlined workflow.

Memory Card Worries

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Today’s Question: While using my wireless remote with my Nikon D7100, I suddenly received a message that my file “may be corrupt”. I had taken about 28 shots in close proximity upon which the camera stalled about 15 seconds, and then proceeded normally again. I am not sure at this point if I need to discard the memory card, or, keep using it? It is a rather new card, and never had a problem with it. What to do?

Tim’s Quick Answer: In a situation like this my approach is to test the entire camera configuration thoroughly, including steps to isolate the true source of the issue. If the problem can’t be repeated, I would feel comfortable continuing to use the memory card (and other components) as long as the problem wasn’t repeated. If the problem ever does occur again, I would absolutely want a solution, which could mean replacing the memory card or having the camera repaired.

More Detail: More than likely this problem had nothing to do with capturing a burst of photos in a relatively short time. Instead, it was likely either a temporary issue with the camera, or a more serious issue with the camera or the memory card.

The camera was very likely “stalled” because the buffer became full. This is not a cause for any real concern. It simply means the camera ran out of internal memory for capturing photos, and so you needed to wait until the images that were already in that internal memory were written to the media card.

To isolate the problem, I would want to capture a somewhat significant number of photos using both the card you were using when the error occurred, and another card to help isolate the issue. Since the problem occurred when you captured a relatively large burst of photos, I would repeat that process in your testing.

If after capturing at least dozens of photos on two (or more) memory cards, if the problem isn’t repeated I would feel reasonably comfortable using the camera and memory cards without replacing them. If the problem occurs with more than one memory card, I would send the camera in to the manufacturer for testing and possible repair. If any card has an error more than once, I would absolutely replace it.

It is a good idea to mark your memory cards in some way, to indicate which one had a problem recently. That way, if this card is in use if the error message is repeated, you’ll know that the card is problematic, and should be replaced immediately.

Mobile Confusion

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Today’s Question: Both my iPad and iPhone now say Lightroom CC although my desktop still says Lightroom Mobile.  I did not download Lightroom CC to my desktop as it is not something I will use.  Has Lightroom Mobile been replaced by Lightroom CC on mobile devices and, if so, what does Lightroom Mobile even mean on my desktop?

Tim’s Quick Answer: The mobile app for iOS and Android devices that had previously been referred to as Lightroom Mobile is now referred to as Lightroom CC. However, this same Lightroom CC mobile app can be used to access images synchronized with either the new Lightroom CC desktop application or the newly renamed Lightroom Classic CC.

More Detail: As many photographers have noticed, the release of a new cloud-based photo service with the name “Lightroom CC” has created some confusion, since there was already an existing software application from Adobe called “Lightroom CC”. That confusion also extends to the version of Lightroom for mobile devices.

The latest version of Lightroom that has been around for about ten years now is now called “Lightroom Classic CC”. This is the version that most of my readers (and perhaps most photographers in general) will want to continue using, at least for the time being.

The new cloud-based photo service is now referred to as Lightroom CC, which includes a desktop application as well as a mobile app and web browser version.

Complicating things a little more, both versions of the Lightroom desktop application (Lightroom CC and Lightroom Classic CC) can be used to synchronize photos to the cloud. In the case of Lightroom CC, all photos are synchronized automatically. Lightroom Classic CC will only synchronize photos you specifically add to a collection that has synchronization enabled.

As a result of all this, the exact same app for mobile devices can be used with either Lightroom CC or Lightroom Classic CC on the desktop. So whether you’ve decided to stick with the existing Lightroom application known as Lightroom Classic CC, or you have decided to make the switch to the new Lightroom CC, the same app for mobile devices (or the web browser version of Lightroom) can be used to access your photos from virtually anywhere.

Lightroom Test Drive

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Today’s Question: Your new Lightroom CC video was, as usual, very helpful. I am a current subscriber to Adobe’s Creative Cloud Photography Plan. Today I received a notification from the Adobe Creative Cloud application advising of updates available for my installed software. I notice that the updates include the installation of the new Lightroom CC and an update to what is now called Lightroom Classic. Can I install the new Lightroom CC and not worry about it automatically importing all my current catalog into it rendering it inaccessible to Lightroom Classic? I’d like to follow your suggestion of importing copies of a few select folders into the new Lightroom CC from my existing catalog for a “test drive”.

Tim’s Quick Answer: The new Lightroom CC will not automatically migrate your existing Lightroom Classic catalog, so you don’t have to worry about that in the context of taking Lightroom CC for a test drive.

More Detail: Lightroom CC includes the ability to migrate a Lightroom Classic catalog, so that you can transition from using Lightroom Classic to Lightroom CC without losing any of the information about your photos in the process. This process will not initiate without you specifically issuing the command within Lightroom CC.

Furthermore, in order to complete the migration process, your Lightroom Classic catalog will be analyzed for any missing images or metadata mismatches. Those issues will need to be resolved before you can fully migrate your Lightroom Classic catalog to Lightroom CC.

I do highly recommend taking Lightroom CC for a test drive before making a decision about possibly transitioning to this new platform. For that text, I highly recommend making copies of a group of your photos (including raw captures), and placing them in a clearly designated “test” folder. You can then add only those photos to Lightroom CC, and text the platform to see if it will meet your needs.

Note that we do have a video course covering the new Lightroom CC that is available through the GreyLearning library here:

https://www.greylearning.com/courses/lightroom-cc