Author: Tim Grey

Today’s Question: I know this is a bit of an old subject, and perhaps the question is no longer really valid or important. But I wonder how many megapixels do we really need? Can you provide some perspective on this?

Tim’s Quick Answer: This is a perfectly reasonable question, and one that I think tends to get the “wrong” kind of attention. In short, while most photographers probably only need a camera with a resolution on the order of no more than 20 megapixels, there are certainly photographers who need more.

More Detail: Ultimately, how many megapixels you need is determined by how large you need to print a photo. Complicating matters slightly is the need to have adequate resolution to crop a photo and still print at a reasonable size, but that is in my mind a secondary concern.

First, let’s consider some extreme scenarios. The first thing a photographer needs to consider when determining their digital camera resolution requirement is how large they want to be able to print their photos. For now, let’s assume the simple resolution numbers required for actually producing a print.

If you need to be able to print up to 40-inches by 60-inches, assuming a photo inkjet print with a 360 pixel per inch (ppi) resolution, you need over 310 megapixels to be represented in the final image. That translates to 14,400 pixels on the “short” side, and 21,600 pixels on the “long” side. For a 20×30-inch print you would need just over 78 megapixels (7,200 pixels by 10,800 pixels).

Of course, this isn’t entirely fair, since you can enlarge (via interpolation) an image with excellent results. As a very general guideline, I recommend limiting your enlargements to no more than about double the width and height of the original capture. So, for a 20×30-inch print you could actually start with a file that represents 10×15-inches of information. Based on the specifications provided above, that translates to a little over 19 megapixels (3,600 pixels by 5,400 pixels).

I think the reason many feel that the megapixel subject is no longer worth discussing is that we’ve reached a point where most photographers will be adequately served by the resolution offered by most digital SLR cameras today. A somewhat “typical” digital SLR with an 18-megapixel sensor enables the production of prints up to about 20×30 inches without much difficulty.

Of course, some photographers need to print much larger than 20×30-inches, and for them a higher resolution camera makes perfect sense. But if you consider 20×30-inches to be a very large print, then around 18 megapixels will be perfectly fine. Beyond that, it is worth considering your needs in terms of output size (and cropping) to determine how much resolution you really need.

But as you can see, with a 40×60-inch print calling for over 300 megapixels worth of information, it isn’t outrageous for photographers to still want ever-greater resolution in their digital cameras. Extremely high resolution cameras may still be a bit expensive, but they do serve a valuable purpose for those who need to produce large output.

Today’s Question: I saw your video on Noiseless Pro. I’ve started using it as a plug-in to Lightroom on RAW images When you finish editing the image in Noiseless Pro, it returns you to Lightroom and saves the changes as a TIFF or PSD. Since you are no longer working on a RAW file, is it better to make your adjustments (blacks, highlights, exposure, white balance, etc) before editing in Noiseless Pro instead of after when your adjusting the TIFF or PSD?

Tim’s Quick Answer: When a plug-in is being employed in this way, I do recommend applying most of your adjustments in Lightroom before sending the image to the plug-in for further processing.

More Detail: I generally prefer to apply noise reduction as early in my workflow as possible. However, I also prefer to leverage the various adjustments within Lightroom for my RAW captures before working with an external editor (such as a plug-in) beyond Lightroom. Therefore, in this case my preference to process the RAW capture within Lightroom as completely as possible will win out.

By optimizing the image in Lightroom first, not only are you leveraging the various adjustments for the original RAW capture, but you are also getting closer to the final result for the image. This will in turn have an impact on how you process the image with other software, such as a noise reduction plug-in.

Naturally you may decide later that additional adjustments are necessary after you’ve created the derivative TIFF or PSD file using a plug-in, and that is perfectly fine. I recommend optimizing the image in Lightroom’s Develop module to achieve a result that is as close to final as possible. Then send the image to the plug-in you wish to use, and process the image accordingly. Later, if you want to apply additional Lightroom adjustments, you can most certainly do so. Provided those final adjustments are relatively modest, they won’t have a significant impact on the overall quality of the final image.

Today’s Question: Like perhaps every photographer out there, I’m familiar with the “rule of thirds”. But I didn’t know about the “golden spiral” until I saw it as an option for a crop overlay. I looked it up and read about it, and it didn’t really make a lot of sense to me. Do you think this is a “rule” I should be paying attention to in my photography?

Tim’s Quick Answer: I put the Golden Spiral “rule” in the same category as the Rule of Thirds. Put simply, I think it can be helpful to be familiar with the concepts behind these guidelines for composition, but you shouldn’t feel the need to strictly apply these “rules” to your photography.

More Detail: Let’s start with the Rule of Thirds. From my point of view, the Rule of Thirds is not really aimed at making sure you align a key subject precisely along a line dividing the image into one-third increments. Rather, this rule is a “shorthand” for a concept, aimed at helping ensure you achieve a degree of balance, interest, and perhaps symmetry in a given photo.

For example, I tend to think about the Rule of Thirds as being more about balancing the “weight” of subjects in the frame, rather than being about strict positioning within the frame. It is often more interesting (and feels more balanced) to have a key subject off to the side, adding considerable “weight” to that side of the frame, with a relatively open space on the other side balancing out that weight.

The Golden Spiral is similarly focused on the distribution of the key subject (and secondary subjects) within the frame. But the spiral itself rarely applies completely to a photographic scene. Very often when I see photos that have the Golden Spiral as an overlay on the image, the photo itself only loosely matches the shape of the spiral. More often than not I get the feeling that the photographer may have simply found an image that worked reasonably well with the Golden Spiral overlay, rather than actually employing the Golden Spiral at the time of capture.

That’s not to say that the Golden Spiral is somehow “bad”, or that you should ignore this guideline of composition. Indeed, my feeling is that it is worthwhile to gain familiarity with guidelines such as the Golden Spiral, which can provide a degree of consistency and balance when applied effectively in a photograph.

So, I encourage you to learn about these various ratios and look for scenes that lend themselves to those ratios. I simply recommend using these various “rules” as compositional guides rather than taking a dogmatic approach. Allow these various rules to help you better see the world, but don’t get locked into always using a specific compositional guideline. The various rules of composition can help you better see the optimal composition so you can make better decisions about your framing, but there is more to making a great photograph than employing mathematical ratios in the composition.

Today’s Question: What new features available in the Lightroom CC upgrade are not included in the standalone upgrade?

Tim’s Quick Answer: The only new features that are not included in the standalone version of Lightroom (version 6.1) that are included in the CC version (version 2015.1) are the new Dehaze adjustment and the ability to apply targeted adjustments for Blacks and Whites (using the Adjustment Brush, the Graduated Filter, or the Radial Filter).

More Detail: There are, of course, other features that had previously been available and are only available in the Creative Cloud version of Lightroom, which requires a Creative Cloud subscription. For example, synchronization to Lightroom Mobile is only supported in the Creative Cloud version of Lightroom. Other features (such as online image storage) that are specific to the Adobe Creative Cloud would also require a subscription.

But in terms of new features in the latest update, so far the new Dehaze adjustment (which I have covered in detail in the June 2015 issue of Pixology magazine) and targeted adjustmetns for Blacks and Whites are the only features included in the Creative Cloud version of Lightroom but not in the standalone version.

Today’s Question: I have used the graduated filter in Lightroom to reduce exposure (darken the sky) and have erased non-sky portions of the effect. In the course of doing so, I erased a bit of sky by mistake. I can’t figure out how correct the mistake without completely redoing the whole erasure. How do I restore the bit of sky I erased to the original graduated filter effect?

Tim’s Quick Answer: Solving this challenge can be quite difficult in terms of producing a result that blends together well. Switching to “unerase” mode is simply a matter of choosing the “A” or “B” brush option after switching to the Brush setting for the Graduated Filter (or the Radial Filter). However, when you use the “A” or “B” brush option the adjustment effect will be revealed completely, overriding the gradient you had already added. You can, however, use the Density setting to help blend the effect.

More Detail: The Graduated Filter creates, as you would expect, an adjustment that transitions from one side of the image to the opposite side. For example, you can darken the sky and have that darkening effect taper off toward the horizon.

Using the Brush option within the Graduated Filter, you can choose the Erase setting and then paint within the image to erase the adjustment effect. For example, if an object extends into the sky that is being darkened by the Graduated Filter, you can paint over that object with the Erase setting so that the adjustment does not apply in that area.

If you accidentally paint with the Erase option outside of the object and into the sky, the easiest approach may well be to simply undo your last brush stroke. This is problematic if you have painted a large area in a single stroke, but this also provides an argument in favor of working with small brush strokes to provide greater flexibility.

In situations where you need to return to an area you had erased an adjustment from in order to reveal small portions of the adjustment, you will want to make use of the “A” or “B” brush option to reverse the effect of the Erase brush option. However, this isn’t as simple as you might have hoped.

When you paint with the “A” or “B” brush for the Graduated Filter (or the Radial Filter), you aren’t simply revealing the effect of the gradient, but rather are replacing that gradient with a 100% adjustment effect in the area you paint. In other words, the area you paint will no longer include a smooth gradation for the adjustment.

You can overcome this limitation to some extent by carefully adjusting the Density setting for the brush. The challenge is to find the right setting, which can take a bit of trial and error. You might, for example, use a very low setting for the Density slider, such as 10% or 20%. Then set the Feather value to the maximum of 100%, so that you are getting the maximum amount of blending. You can then paint multiple times over a given area to build up the effect to achieve a good blend.

Of course, all of this careful work will go by the wayside if you then decide to change the shape of the gradient you created with the Graduated Filter. If you change the size of the transition or the position of the gradient, the area you carefully painted will no longer match up.

These various issues demonstrate some of the shortcomings of the targeted adjustment features within Lightroom. While it can be tremendously helpful to be able to combine the effect of the Graduated Filter with the Adjustment Brush in a single combined mask, you still don’t have the degree of flexibility and control that is available in Photoshop.

As a result, I tend to use Lightroom only for relatively basic targeted adjustments. Even then, I am careful to make sure that any painting I have done on the mask for the targeted adjustment is highly accurate. But for layer masks that require precision, or where I want to preserve maximum flexibility, I will send the image to Photoshop rather than working within Lightroom.

Today’s Question: How do you go about editing an existing watermark in Lightroom?  If you go through the process, making changes to a watermark that you already have, when you get to the point of saving it, Lightroom forces you to give it a new name. It does not allow me to change an existing one. I know I have done this in the past; there is a trick to it, but I can’t remember what that trick is. Thanks!

Tim’s Quick Answer: In the Watermark Editor dialog you can actually choose “Update Preset” from the popup at the top-left to save changes to the current watermark.

More Detail: To get started editing a watermark, choose Edit Watermarks from the Lightroom menu on the Macintosh version of Lightroom or on the Edit menu on the Windows version of Lightroom. This will bring up the Watermark Editor dialog, where you can choose the watermark you want to edit from the popup at the top-left of the dialog.

You can then make any changes you’d like to the settings for the current watermark. When you’re finished, click the popup at the top-left of the dialog and choose the “Update Preset” option. Note that this option will also indicate the name of the current preset, and that it is necessary to select a specific preset from the popup before you start making changes in order for this “Update Preset” option to appear.

Today’s Question: During your workshop in the Palouse you said that when you are shooting in Shutter Priority mode you run the risk of “running out” of apertures, while in Aperture Priority mode you don’t have as much risk of running out of shutter speeds. Can you clarify what you meant by this, as the more I think about it after the fact the less I understand! Thank you.

Tim’s Quick Answer: Put simply, with a typical lens you have a smaller range of aperture settings compared to shutter speed options for your camera, providing more flexibility when using Aperture Priority mode compared to Shutter Priority mode.

More Detail: Let’s consider a couple of relatively typical examples for the range of available apertures and shutter speeds.

A typical lens might offer a range of apertures from f/2.8 when the aperture is wide open to f/22 when the aperture is stopped down to the minimum aperture size. In one-stop increments the available aperture settings would be f/2.8, f/4, f/5.6, f/8, f/11, f/16, and f/22. That’s a total range of six stops between the largest and smallest aperture size.

A typical digital SLR might offer a range of shutter speeds that go from 1/8000th of a second for the shortest exposure duration to 30 seconds for the longest exposure duration (with longer exposures possible through the use of a cable release). In one-stop increments there are a total of nineteen shutter speeds to choose from, representing a range of eighteen stops. That’s three times the exposure range (eighteen stops versus six stops) for shutter speeds compared to aperture settings.

What all this means is that when you set a fixed shutter speed in Shutter Priority mode, you are at a greater risk of “running out” of aperture options. There is less risk with Aperture Priority mode, because there are more shutter speed options available.

Of course, it is also important to keep in mind that for a given scene you may want to limit your exposure settings significantly compared to the many options available. For example, for a fast moving subject you may want to use a shutter speed of 1/125th of a second or faster, greatly reducing the total number of shutter speed options available to you.

The key is to be aware of what settings will work best when photographing a given subject, and anticipating when you might run into a limit based on the exposure mode or specific settings you’ve used.

During my Palouse Photo Workshop, for example, we had the opportunity to photograph crop duster aircraft spraying fields of crops. Due to the rotational speed of the propeller, a shutter speed of about 1/250th of a second was ideal. If the ISO setting on the camera had been set to 800, for example, even the smallest aperture size (f/22 in the example cited above) would result in an over-exposed image.

Today’s Question: As a follow-up to yesterday’s question: I know you have covered your approach to star ratings in the past, but I can’t find that info. Could you summarize how you use star ratings, or point me to the info you’ve already published?

Tim’s Quick Answer: I employ star ratings in a multiple-pass review process. On my first review pass, I assign a one-star rating to the photos I like, with no star applied to those I don’t feel are my best. On a second pass I will “upgrade” photos I feel are deserving to a two- or three-star rating. Later, I might upgrade my very best images to a four- or five-star rating.

More Detail: There are several things that I consider to be key pillars of this approach. First, I don’t use star ratings in the “normal” way. A one-star rating represents an image I think I might use (or that I simply like) rather than a “bad” image. A two- or three-star rating indicates a photo that is among the best from a photo shoot. And a four- or five-star rating represents a photo that is among the best I’ve ever captured.

By taking multiple passes to review my photos, I feel that I’m better able to rank my photos in a way that is helpful to me. My first review pass is essentially a “yes or no” pass, where I decide which images I think are worth using for some purpose and which photos I’ll likely not use. In many respects this is the same approach you might use when employing the pick or reject flags in Lightroom. Later passes allow me to further evaluate my photos to decide which are really going to be favorites.

In addition, this approach provides a bit of time between review passes (when possible) so I can separate the emotion out of my review. Right after an exciting photo shoot, I might be a little more generous with my star ratings than I would be after waiting a day or two to perform an additional review.

I’ve written about my approach to using star ratings in more detail in the article “Star Rating Strategy”, which appeared in the November 2014 issue of Pixology magazine. If you’re not already a subscriber to Pixology magazine, you can get more details at http://www.pixologymag.com.

Today’s Question: How do you distinguish between the use of star ratings and pick flags [in Lightroom] when identifying your favorite images? Do you use pick and reject flags for the first pass of review and then star ratings to “grade” the images with a second review?

Tim’s Quick Answer: I actually avoid the use of pick flags altogether, because pick and reject flags are a Lightroom-specific feature and thus these flags can’t be viewed in other applications such as Adobe Bridge. Therefore, I only use star ratings to identify favorite (or not-so-favorite) images.

More Detail: While I certainly anticipate that I will be using Lightroom to manage my photos for many years to come, I still prefer to avoid the use of metadata fields that are not part of an established metadata standard. This is the key reason I use star ratings instead of pick flags.

It is worth noting that I also prefer the “stack ranking” approach of star ratings, rather than the “yes or no” approach of pick and reject flags. But the primary reason I use star ratings in favor of pick flags is that I can view star ratings in any application that allows me to browse the metadata for my photos, and I also then don’t need to worry about any potential transition to another application in the future. My star ratings will be visible to virtually any image-management software, while pick flags will not be.

For these reasons, I recommend that photographers consider the use of star ratings rather than pick flags. If you prefer the “yes or no” approach that are embodied by pick flags, you can simply adapt your approach to using star ratings to provide this type of solution. For example, you could use a workflow where a five-star rating represents a “pick”, a one-star rating represents a “reject”, and a three-star rating represents a “not-yet-reviewed” rating. You could then assign all new captures a three-star rating, and move from there during your review process.

But the bottom line is that I use star ratings as my primary (and really exclusive) tool for identifying my favorite images from a given trip or photo shoot.

Today’s Question: Could you expand on how you exposed for your Milky Way photo on page 48 of the November 2014 issue of Pixology magazine?

Tim’s Quick Answer: The photo referred to in today’s question features a rock formation near Castle Valley, Utah, with the Milky Way in the night sky. The image was captured with a 24mm lens focal length at an aperture of f/4 and a shutter speed of 15 seconds at 6400 ISO.

More Detail: You can view the photo referred to in today’s question on my 500px page here:

https://500px.com/photo/91347311/milky-way-from-near-castle-valley-utah-by-tim-grey

The first key to capturing a photo of the Milky Way is to determine the time that the Milky Way will be visible in your area, and to make sure that this time will be at night with a clear sky. It is also helpful if the appearance of the Milky Way will coincide with a time of night when the moon is not going to be above the horizon, or when there is a new moon, so that the light from the moon doesn’t interfere with your exposure. It is also important to be as far away from bright lights (such as towns and cities) so the overall sky will be as dark as possible.

I then typically aim for a 15-second exposure, in large part to minimize the appearance of any star movement. The actual limit of your exposure duration is determined by the focal length of the lens, and you can employ a longer exposure if you are using a lens with a shorter focal length.

One of the most challenging this to achieve with a night shot such as this is accurate focus. In theory you just want to set the lens to focus at infinity, but in my experience this often does not produce the best results. I prefer to use the live view display on the camera, zoomed in on some stars, so that I can use that as the basis of establishing a manual focus adjustment. Of course, even with exposure simulation in the live view display it can be very difficult to see the stars and achieve optimal focus.

Naturally you’ll need to employ a tripod, and I also recommend using a cable release to ensure you don’t impart movement to the camera when triggering the exposure and to make it a little easier to work.

A good foreground element silhouetted against the sky can also add a degree of interest to a photo that includes the Milky Way. Most important, you should have some fun and enjoy your time out among a darkened landscape when photographing the night sky.