Is raw overrated in the modern world? Are the JPEG sceptics justified? Tim Daly looks at what the truth is

Editing JPEGs

The most efficient way to edit JPEGs is to use Lightroom, which preserves the integrity of your original by never saving edits back onto the file.

As you edit in the Develop module, you can use the Before and After view mode to check how much noise your creative moves are adding, as blocky artefacts will become more prominent in areas that receive the most editing. The results of excessive editing become even more pronounced if you decide to make black & white conversions.

For Photoshop users, however, it’s essential to make a duplicate version of your JPEG to use solely for editing. Unfortunately, this will impact on your overall storage as your image library grows 
over time.

JPEGs Fact from fiction - Pic_4_1

Left: JPEG artefacts magnified; Right: Black and white conversion. Excessive editing and sharpening will magnify JPEG artefacts, especially if you make black & white conversions

If you are using Photoshop, open your JPEG and immediately do a Save As and save a duplicate version of the file as a TIFF or PSD to use for editing.

If you work on your original JPEG and keep pressing Save, you will recompress it each time and create gigantic artefacts in the process.

Confusingly, the damage caused by recompression when resaving isn’t visible while the original JPEG remains open in your application during an editing sequence. It’s only when the file is closed and re-opened that you see the irretrievable damage you have caused.

JPEGs give you a limited amount of colour and tonal information to work with, so if your creative editing workflow includes either black & white conversion, drastic colour change or complex retouching, you are better off shooting raw.

Creating JPEGs in your image editor

You can turn any image format into a JPEG via image-editing software and, unlike shooting, you can preview any adverse compression effects before you commit to save.

Lightroom users can create JPEGs through the File>Export command and choose a range of quality options on a simple 0-100% scale.

JPEGs - Fact from fiction

Photoshop CC’s Export As dialog, showing restricted Metadata options. You can still retain copyright and contact details, though

For Photoshop CC users, there are three methods available, each with increasing levels of sophistication.

In addition to the usual File>Save As command, the File>Export As function provides a larger dialog with options to resize and remove metadata from your file.

The File> Export>Save for Web (legacy) dialog offers the best range of tools for packaging up your work as JPEGs.

Images can be previewed in a two or four-up window, so different quality settings can be compared to each other. Current document sizes are displayed at the base of each image together with the estimated time the image would take to download on a range of different bandwidths.

The Save for Web controls give you the most control over retaining metadata, unlike Export As which, at best, strips most of the shooting information away but retains copyright and contact details.

JPEGs - Fact from fiction

Lightroom provides much fewer preview and prediction tools, using a basic File Settings dialog

Both of these advanced methods of creating JPEGs allow you to change the colour space of your file to the generic sRGB if your image is destined for web use. However, if you want to replace the file’s colour space with a specific print profile provided by a professional lab, you will still need to use the Edit> Convert to Profile step before reaching the Export As or Save As stage.

How to edit JPEGs in Lightroom

1. Make images look punchier

 JPEGs - Fact from fiction
Highlights and black points are often clipped in JPEGs, so your first task is to move the sliders for these areas until their corresponding triangle turns white (that’s if they are not white already.) Highlight is top right, Blacks top left.

2. Fix under or overexposure

JPEGs - Fact from fiction
Use the Exposure slider to fix any under or overexposure. This is calibrated in stops, so my -0.35 edit here makes the image darker by 1/3 of a stop.

3. Tweak the white balance

JPEGs - Fact from fiction

Tweak the White Balance using the Temp slider. Here I added a small amount of Yellow (+3) to make the image warmer.

4. Add a Vibrance edit

JPEGs - Fact from fiction

You can rescue any washed-out colours by using a tiny Vibrance edit of +6. This will boost only the muted colours and leave the saturated ones well alone.

5. Tweak the sharpness

JPEGs - Fact from fiction

Finally, tweak image sharpness using the Detail tools. Use the following settings as a starting point: Amount 50, Radius 1.0 and Detail 25.

Packaging and dispatch

Even if you use a raw-file workflow, JPEG is the ideal format for saving and packaging images for web use, or to dispatch to an online printing service. All C-type minilabs are designed to work with JPEGs.

This process of packaging up a version of your image for a specific output means you are making a new JPEG for a single-use event. A good compromise is never to go below 20% of your original data size, so in Lightroom do File>Export and in the File Settings panel select JPEG as the Image Format and Quality at 80%.

JPEGs - Fact from fiction

All digital C-type minilabs are designed to work with JPEGs, so there’s no advantage in supplying TIFF files to your lab

If you are a Photoshop user, do File>Save As, then select JPEG as the Format, then set Quality to 10 (Maximum).

Once you’ve dispatched or uploaded your JPEGs, avoid reintroducing them to your workflow, as you 
can never extract the edits that have been ‘baked’ permanently 
into the files.

  1. 1. What exactly is compression?
  2. 2. Camera settings
  3. 3. Editing JPEGs
Page 3 of 3 - Show Full List