Do you have a good grasp of the different image file formats available? Do you know the difference between a lossless and lossy file? For instance, do you know when to set your camera to record images on JPEG or RAW? As a retired scientist and self-proclaimed geek, I often find myself obsessing about every single little detail. Whenever I face a new subject, I quickly find myself digging through the endless internet universe. Usually, my initial research creates more questions, and I end up spending days learning about a topic that shouldn’t take more than 10 minutes of my life. In this post, I promise to share everything that I’ve learned about the different image file formats available to us – photographers. All I ask for is 15 minutes of your attention.

Are you ready? Let’s do it; I promise it will be fun.

1. Lossless vs. Lossy file:

Instead of starting this post explaining the difference between the files, I want to briefly explain the first essential concept we should learn about digital files – file compression. All digital data are compressed to be recorded. However, the compression method used during the data acquisition (a.k.a capturing the image) can drastically change our ability to use those data later in post-processing. In general, data compression is divided into two main categories – Lossless and Lossy. The main difference between these two methods is that while Lossless format records data without losing data, the lossy compression “drops” unnecessary or redundant information to reduce file size [1].

The advance of digital photography during 1980 started to create standards for image compression. Initially, the cameras only captured images in Lossless format. But, the quick expansion of the digital format added to the costs of storage forced the industry to start using a lossy compression method. And that’s how JPEG became one of the most ubiquitous image formats in the digital space.

2. RAW vs. JPEG file:

The RAW vs. JPEG comparison is the most relevant for photographers. So, I decided to dedicate a special session to compare these two formats. And since you – the astute reader – already understand the difference between the different compression types, I’m confident that you have already started to visualize the differences between RAW and JPEG. While the RAW file uses a capture method that records images without losing data, the JPEG file ignores some original data to compress the final file.

In light of this information, you are probably wondering why that’s important for your photography. In fact, I didn’t understand why those large and hard to work with RAW files were appealing for some photographers. Why not just use JPEG format? A format that can be easily opened by our computer? And those were the questions that made me keep using JPEG even after buying my first RAW capable DSLR camera.

But, after some research, I realized the magical power of shooting using the RAW format.  In brief, the data captured by a camera using the RAW format allows photographers to post-process images more robustly. In fact, a RAW image straight out of the camera usually looks very flat with muted colors. And that’s why I like to imagine the RAW format as a film negative and JPEG as a developed image.

3. Practical aspects:

Congratulations, you made it through the first session. You read the most technical part of this post, and that’s pretty awesome. Now, you’re equipped with enough information about digital file compression to impress your friends on the next trivia night.  But why stop now? Let’s move forward, and use this solid base to explore the practical aspects of those different image file formats. In the following comparisons, I will also explain a few other Lossless formats widely used in photography – TIFF, PNG, DNG, and PSD.

JPEG:

Let’s start the conversation with the only Lossy format in this list. The JPEG acronym stands for Joint Photography Experts Group, and it was first introduced to the public back in 1992. With a compression rate of approximately 10:1, JPEG quickly became the industry standard for sharing digital images over the internet. The significant advantages of the JPEG format are the file size and ease of use. The combination of small file size and visualization ability without specialized software makes the JPEG format extremely convenient to work and store images. More recently, another factor supporting the exponential JPEG growth was the creation and expansion of the internet and social media platforms. The majority of sites and social media only accepts the JPEG format.

But it would be best if you didn’t get lured by all the benefits of JPEG files. In fact, the JPEG format is far from perfect when it comes down to capturing images. When you set your camera to JPEG, you allow the camera algorithm to decide key artistic and creative factors.

Wait; what?  Yes, that’s right. To discard “irrelevant” information to compress the file, your camera decides on key image factors such as contrast, vibrance, saturation, among others. That’s the reason why a JPEG image will always look better than a RAW image straight out of the camera. And since the captured file has lost a lot of information during the recording stage, you will not be able to make any major adjustments to the file after the capture. Imagine JPEG files as a printed image. Once you have it on your hands, it will be tough to make any significant change.

RAW:

First, it’s essential to realize that each camera manufacturer will have its own proprietary RAW format. For example, Canon RAW images have a CR2 extension, while Nikon raw files are recorded as NEF files. Back in the day, it could be a challenge to find software to open your RAW file. Back in 2012, I remember having to wait for Adobe to release a Lightroom update so I could open the raw files from my brand-new Canon 6D. This seems to be less of a challenge nowadays since Adobe Cloud provides daily updates.

But, all that initial pain of working with the RAW format quickly disappears when you discover the power of having all the information recorded in each image file. Since the RAW files are digital negatives, you have the ability to develop your images in ways that will express your artistic view. Because the RAW files are very bland straight from the camera, anyone using this format should be ready to dip their toes in the post-processing world. Whether you decide to spend hours tweaking the colors using specialized post-processing software or just making global adjustments utilizing your camera manufacturer’s software, you will have to allocate time to develop your RAW file.

As someone that thoroughly enjoys spending hours on post-processing, I love capturing all my images using the RAW format. After years of photography, I have finally developed a backup system with plenty of redundancy and space to store large files. Thus, since I have the necessity of editing my images to create appealing photos to sell for clients and storage space is not critical, I feel that the RAW format is the only logical choice for me.

Be realistic about your necessities. 

Before you start shooting in RAW format, I would strongly advise you to stop and reflect on your goals. Is storage space an issue for you? Are you ready to buy extra hard-drives or to subscribe to cloud storage services? Do you have the patience to develop your RAW files? If yes – the RAW format is the one for you. But if you said no to one of those two points, maybe you should consider using the JPEG format.

TIFF:

Yes, my Canadian friends might believe that TIFF stands for the Toronto International Film Festival. But, for us photographers, the TIFF acronym stands for Tagged Image File Format. This Lossless format is broadly used for printing purposes, as the format can store up to 16.7 million colors and can be easily converted to CMYK color space. The TIFF file was first introduced in 1986 and quickly became the format of choice among graphical artists, publishers, and photographers planning on printing their work. The TIFF file can be easily open on any computer, as it doesn’t require specialized software. But, it’s large size makes this file format not suitable for sharing and distributing over the internet.

Usually, the uncompressed nature of the TIFF files is suitable for post-processing. Despite the ease of use of TIFF files, they are often larger than the RAW format, making it hard to justify using such a format for storage. Thus, photographers only use this format for printing purposes.

Proprietary Files – The Adobe story:

Adobe software solutions have been around since the beginning of the digital era. The company has pioneered several (if not all) fields of digital art. This constant drive for innovation consolidated Adobe as one of the leading software developers in the photography world. Nowadays, Photoshop and Lightroom represent a large share of the photo editing software market. And the two main proprietary file formats from Adobe are PSD and DNG.

DNG:

The DNG format was created in an effort to standardize RAW files. By converting the RAW file from camera manufacturers to DNG format, users could open all different RAW files using any Adobe software. This was particularly relevant before the transition to Adobe Creative Cloud (CC). Before the Creative Cloud, users would buy Adobe software and keep using that software for years before upgrading to a newer version. However, sometimes the “old” software didn’t support the new RAW files created by the new cameras. The solution to this problem? The DNG Converter software. After buying a new camera, photographers had to download the free DNG Converter to transform the RAW files into DNG before editing the images in Photoshop or Lightroom.

Nowadays, with the constant updates from Creative Cloud, users don’t have to worry about this extra step – as all the algorithms to convert the new RAW files are quickly incorporated in Lightroom.

PSD:

One of the most popular software in the digital art space, Photoshop was first introduced to the public in 1988 [2]. Its presence among digital artists is so ubiquitous that the software’s name became an actual verb in the English language. Photoshop is one of the most powerful and complex software used for photo-editing  – watch this video to learn more about Photoshop and this long-tutorial to see how to use it during Post-Processing. Personally, I use Photoshop daily to edit my photos and to create digital art (such as banners and ads) for clients. Now, you as a photographer might be asking why I would save an image in the PSD format?

The straight answer is – because PSD files allow you to save layers. Probably, the most important aspect of Photoshop is the ability to work with non-destructive layers that can be re-visited in the future. Let’s say, you decide to scroll through your archives, and you find a 2014 photograph saved in PSD format. It’s a nice image, but you realize that the purple sky looks a lot like Armageddon (maybe that has happened to me). Since you edited your image using layers and saved the final file using the PSD format, you can open the image and adjust only the necessary layers.

PNG:

You made it. This is the last of the Mohicans in this thorough comparison between the different image file formats. The PNG file acronym stands for Portable Network Graphics, and it was first introduced in 1995 as an improvement to the GIF format (a file format seldomly used by photographers). This lossless format is the only file type that allows the use of transparency. This particular aspect makes the PNG format the ideal candidate for photographers looking for ways to overlay their logos on top of images.

Congratulations

You have finished reading this thorough revision on all the different image file formats. I hope you have enjoyed the reading and learned something new along the way. Honestly, I believe that learning when and how to use those different image file formats helped me during my photography career. This knowledge helped me create my own logo, save and upload images to my website, send images out to magazines and printshops, and ultimately – how to save and store my photography edits.

I look forward to hearing from you – how do you deal with all the different image file formats? Let me know what you think in the comment section, and if you liked this post, please consider subscribing to the website to get notifications. That would mean a lot to me.

Have a wonderful day.