Technical tips for amateur photographers

Sometimes there are tips I don’t offer to experienced photography enthusiasts unless they ask the right question first. This is because I feel they should already know all this, and might be offended that I could imagine they didn’t – especially if the issue is pretty important.

But… in practice nobody can know everything. Especially when some things in the photography world have changed gradually or are non-trivial. So many photographers still use best practices that were suitable years ago, but may be outdated. So, pssst… here is a checklist of several such issues. Where applicable, I tried to add evidence.

1. Good cameras and photographers deserve Raw

The question is whether to set the camera so that it generates Raw image files. Your camera’s default is to generate JPG files. Raw files can be seen as the camera’s native format, and may need to be converted to JPG at some point.

Adobe called their open Raw format “Digital Negatives” or DNG. So, to borrow their analogy, the underlying question is whether to save or to automatically discard your digital negatives. If you currently generate JPG files, you are automatically developing and discarding those “negatives“. As the analogy suggests, this is automatic and thus convenient. But it has certain drawbacks.

Originally Raw files were considered a tool for pixel fetishists: the digital photo that you really needed (for printing, for mailing, for websites, for displaying) was in JPG format because most software could only handle JPG files. So Raw files added an extra step and were thus considered by many to be a waste of time, energy and storage space. Furthermore the JPG file format is well standardized, while Raw files were vendor-specific image formats that might become obsolete in the future.

This situation has changed. By now JPG is a 20 year-old image format that is still good enough as an output format, but isn’t really sophisticated enough to store the images which current camera sensors can capture. So assuming you have a good camera, one could argue that you lose a few year’s worth of camera industry innovation if you choose to exclusively work in Raw. Obviously not everybody will care, but it is at least worth knowing what your choice is.

In more technical terms, current sensors have 12 or 14 bit of accuracy and JPG was designed in the time that 8 bit was considered enough. Furthermore classic JPG was designed to discard fine detail and color nuances in order to save storage space: JPG is essentially a form of “lossy compression”. To JPG‘s credit, the tradeoff between image quality and file size is adjustable, but cameras only give you limited control over this tradeoff. Raw files, on the other hand, use “lossless compression”, store all 12-14 bits of information and produce files that may be 1.5-4× larger (this depends on the ISO setting).

Here is an example of the image quality lost by using JPG. These are 100% crops of an image of a bee keeper’s working clothes taken with my Canon 5D Mark II. The Raw and JPG images were actually simultaneously recorded in-camera and are thus automatically generated from the same exposure. I selected the camera’s highest quality setting. No changes were applied to the resulting Raw and JPG files in post-processing: these are pretty much the defaults.

Hold the mouse over the images to exchange the Raw and JPG images. Loading may take a few seconds.

The JPG version clearly has less contrast (but that could be fixed in post-processing) but a lot of details are lost: at this extreme magnification, the photo starts to look like a water-color painting.

The full image (100 ISO, 70-200mm f/4L IS lens, 106 mm, f/6.7, 1/500s).

The claim that “Raw is an extra intermediate step” is a misconception: when you print or view or zoom into an image, you are generating a new derived image – generally at a lower resolution. So in a way, JPG is a detour rather than the short route: your camera natively speaks Raw, compresses the image because storage space was formerly a major concern, after which the image is decompressed so that it can be used (viewed, edited, printed), can be sent (e-mail) or can be shared (web).

In modern software like Lightroom or Google’s Picasa, Raw and JPG both serve as valid input formats. When you adjust an image (e.g. change brightness, crop it, remove dust, adapt the contrast…) no output image file is generated. Only the (tiny) adjustment commands themselves are saved.

Photoshop and its alternatives also support all major Raw formats and can generate many different output formats. If you may edit the image again in the future, JPG is seldom recommended as the intermediate storage format because every additional detour via JPG causes more loss of quality.

Thus, although Raw has few drawbacks nowadays, here are some legitimate excuses to still use JPG:

  1. If you have a camera phone or compact camera and it probably only supports JPG. This means the camera is probably not good enough to worry about subtle differences in image quality.
  2. In general, if quality is not an issue, JPG is good enough. An extreme example: I use JPG to take pictures of street names, etc instead of writing them down 😉
  3. If you take studio images, you may have the time and skills to tune the lighting, composition and camera settings so that you don’t need to adjust the image at all in post-processing. If you never change your image (no dust, ideal exposure, ideal contast…) JPG may be good enough. You still loose some sharpness, but for portraits sharpness may even be somewhat undesirable.
  4. If your camera has an obscure proprietary Raw format, you may want to use something else for archiving. This is seldom the case today: small manufacturers use Adobe’s well-documented (but not really open) DNG Raw format and major manufacturers get enough software support for their current and older formats anyway.

To strengthen the case for Raw, Your Honor, here are some more comparisons:

Hold the mouse over the image to swap the Raw and JPG images.

Again, the JPG version largely loses skin texture and fabric detail. You won’t really notice this on small prints, but it will limit your ability to crop or enlarge your pictures.

The corresponding full image (100 ISO, 111 mm, f/6.7, 1/500, 70-200 f/4L IS)

As a last example, here is a macro image of bees taken with a macro lens (while wearing the protective clothing you saw in the first picture).

Hold the mouse over the images to swap the Raw and JPG images.

The JPG has less sharpness for the hairs, less texture in the smooth bits and darker shadows (although the latter can likely be fixed).

The corresponding full image (320 ISO, 100 mm f/2.8 macro lens, f/5, 1/250)

More examples at higher ISO values and using different cameras can be found on here on the site. Note that when you compare different cameras, you are often also varying resolution and varying the choice of lens. But the a quick look at different cameras confirms the conclusion that a good photo made with good equipment deserves Raw.

2. Photoshop or Lightroom?

Adobe’s Photoshop dates back to the late 1980’s. It is one of the most famous software tools and even brands in the world. Unfortunately it has also grown into a huge program with many features and large add-ons (e.g. Bridge). This is partly because it is used by very diverse types of users. And this is partly because it was designed to be the single, ultimate tool for modifying or generating images.

It is consequently reasonably tricky to learn, and requires a pretty disciplined approach to manipulating images.

In 2006 Adobe launched a new product, Adobe Photoshop Lightroom, that only targets the basic needs of (serious) photographers. It is thus designed to cover pretty much everything a photographer does with photos. It focuses on helping the photographer do common tasks efficiently – rather than on providing an ultimate toolbox which can do everything… providing that you can find out how.

The main benefits of Lightroom (compared to Photoshop CS are):

  1. It is lightweight, but still targeted at professional photographers and serious amateurs. “Lightweight” implies easier to use, easier to learn and significantly less expensive.
  2. Lightroom also keeps track of your files (thus covering Bridge functionality). It does keywording, searching, browsing, etc. The files themselves can be stored with normal file names in a normal directory structure. There is support for having different versions of a file (“virtual copies”).
  3. You never create output images unless you need to send (“export”) a file to someone/somewhere else. You only store the original image. And information is recorded on what modifications you selected. This allows you to change your mind and adapt the image later without any loss of quality. It also makes it irrelevant in what order you do modifications, and it avoids having to store and track multiple intermediate or alternative versions of the same image.
    This approach actually works faster on large images because the computer only calculates changes at the resolution or the crop that you are viewing at that moment: on a screen you either see a low resolution overview image, or a high-resolution partial image. This is because screens are typically 1 to 2 MPixels while your camera is likely between 10 and 20 MPixels.
  4. There is no support for layers. Some uses of layers are handled by the previous point. But there are things you can do in Photoshop which you simply cannot do in Lightroom. Many professional photographers thus actually own both, but spend most of their time in Lightroom.
  5. Lightroom covers the entire workflow in one user interface: importing and managing collections of images, common and some less common image enhancements (“Develop”), professional quality printing, and exporting images to a website or web service.

So if the final output of your work is typically still essentially a single photo, Lightroom (or its competitor Aperture) may give you all you need in an elegant, efficient but professional-strength tool.

Here is a rather extreme example of how far Lightroom can adjust a (Raw) image.

Original version of 2011_Paris_249 (100 ISO, 105 mm, f/5.6, 1/200).

Edited version that stresses the shadows above (!) the tower.

The changes made to this particular image were:

  1. Reduced the exposure by 3.5 (!) stops. Yes, the original was a Raw file.
  2. Removing dust spots
  3. Rendering as black and white.
  4. Cropping off the bottom of the image
  5. Increasing the contrast
  6. Applying automatic lens corrections for distortion, vignetting, etc

The order in which such changes are made is irrelevant – unlike Photoshop, the enhancements are applied in a fixed order determined by Lightroom. This “fixed order” may sound inflexible, but actually allows you to apply the required changes in any order you like and backtrack on earlier decisions without having to start over.

Below is a cropped version of the original image superimposed with the final image. The images move slightly due to the applied lens correction.

Cropped original version of 2011_Paris_249. Place mouse over image to see edited version.

Obviously many images need less or even no editing. But, on the other hand, Lightroom even supports some enhancements that are fancier than those shown above: gradient filters and brush-based local enhancements.

Some of the main things you cannot do in Lightroom 3.x:

  • no layer support (although there is a form of masking)
  • no hundreds of creative filters
  • no HDR or panorama stitching (Lightroom can invoke Photoshop to do both)
  • no soft proofing of print jobs (this has been added in Lightroom 4)

So … for photographers, using Photoshop Lightroom as your main tool saves you time. And the end result is likely to be a bit better. This is simply because Lightroom was design for photographers. Photoshop nowadays targets graphic artists, website designers, engineers, print ad developers, etc. You may find that you still need Photoshop occasionally. But Lightroom provides integration support for extra tools and plugins – including Photoshop.

Candidates for additional topics in this article or series:

  • Calibrate the colors and brightness of your screen.
  • I recommend using adding artificial vignetting to many photos
  • image stabilizers as “digital tripods”. 10x slower shutter speed.
  • Beginners should never use the flash.
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2 Responses to Technical tips for amateur photographers

  1. Chas.: You’re on the right track. In my current workflow, I correct my raw files as needed in ACR, and save to a PSD file for additional CS3 tweaking, all in non-destructive adjustment layers and smart layers (for Shadow/Highlight, noise reduction and sharpening). This is my archive file for future use or changes. I custom sharpen for each print size: an 8×12 gets different sharpening than a 16×24, and save a different file version for each print size. And while I use a fully calibrated system, with the “custom” ICC profiles provided by Imageprint RIP, and soft proofing in CS3, there are still small adjustments needed in the file to get to that “fine-art” print. I make those file adjustments in the adjustment layers as needed (often print size dependent as with sharpening), and when I’m satisfied, I flatten the layers, convert to 8 bit color, and save this as a TIFF file specifically for printing. The only other use I have for TIFF files is if I’m sending a file to a printer, or someone who may not have software to open a PSD file (TIFF is a universally recognized file format). In a nutshell: RAW for the legacy archive, PSD for ongoing work and the legacy archive, TIFF for printing and sending out hi-res images, and jpeg for email and snapshots.

  2. The major actor in this case is the Discrete Cosine Transforamtion (or DCT) which divides the image into blocks (usually 8×8 pixels) and determines what can be “safely” thrown away because it is less perceivable (the higher the compression ration/lower quality JPEG, the more is thrown away during this step). And when the image is put back together a row of 24 pixels that had 24 different tones might now only have 4 or 5. That information is forever lost without the raw data from the sensor recorded in a Raw file.

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