Month: October 2020

Today’s Question: Your post [which referenced using a laptop computer exclusively without using a desktop computer] piqued my interest regarding doing away with using a desktop. I can’t imagine doing all the work I do on a laptop and am curious if you wouldn’t mind sharing the rationale or just give the advantages of laptop over desktop, at least for you.

Tim’s Quick Answer: My original rationale for abandoning a desktop computer was quite simple. I got to the point that I was traveling so much that I wouldn’t have access to a desktop computer that remained at home while I was away. In the approximately ten years since I started only using a laptop computer, I’ve never missed having a desktop computer.

More Detail: Before the current pandemic caused my travels for the year to be canceled, I was scheduled to be traveling for almost ten months of this year. If I had a desktop computer sitting at home, I would hardly ever be able to use it.

Around ten years or so ago, as my travels were starting to get more extensive, I originally had a desktop computer at home that I could remotely access with an Internet connection. However, if something went wrong with my desktop computer, I might lose remote access for the remainder of a trip. That could prove problematic.

So, I opted to make a laptop the only computer I use. Not only does that mean I don’t have to manage a desktop computer at home, but it also means I never have to swap data between computers. I have access to my core applications and data anywhere I go as long as I bring my laptop. And I typically have my photos and other data with me as well, as long as I’ve brought my external hard drives.

Even though I haven’t traveled in the past six months due to the pandemic, I still find it advantageous to use a laptop computer exclusively. This setup makes my work more flexible, with the ability to switch locations at any time, take my laptop with me, and still have everything I need.

To be sure, you can potentially get faster performance with a typical desktop computer compared to most laptop computers. There are certainly times when I wish my laptop was as fast as the top desktop computer. I also wish I could have more internal storage on my laptop, so I wasn’t as dependent on external hard drives. But on balance, I’m happier using a laptop, and can’t imagine ever getting another desktop computer.

Today’s Question: How can I tell if an image is raw? I know that the file extension can be helpful to tell if a file is in raw format. Usually. But what if I do something like export a JPG file to DNG from Lightroom Classic? And then I import a different Canon raw capture as a DNG. How can I look at the two DNG files and determine which one is a true raw image?

Tim’s Quick Answer: I don’t know of any software that makes the task of identifying the source of a DNG file particularly easy or reliable. However, you can open a DNG file with a text editor and search for an indication that the file was converted from a different file type.

More Detail: With a proprietary raw capture format, you can essentially just tell from the file type that the file is indeed a raw capture. The same is not true for an Adobe DNG (Digital Negative) file.

A DNG could be an original raw capture, as a variety of cameras support raw captures saved directly as a DNG file. You can also convert a proprietary raw capture to the DNG format, with the option to embed the original raw capture in the DNG file if you’d like. Both of these would provide you with a file that could be considered a raw capture.

However, it is also possible to convert other image file formats to DNG. You could, for example, capture a JPEG image with a smartphone and then convert that JPEG image to a DNG file. This represents a DNG created from a non-raw source, meaning there is full color information for all pixels in the image, unlike most raw capture formats. This type of DNG file is referred to as a Linear DNG.

If you open a DNG file with a basic text editor on your computer, you can search for the text “converted”. With the software I’ve tested (which in this case only includes Adobe software), a DNG file that was converted from another file format will include text in metadata describing the conversion. For example, a JPEG I converted to DNG includes the text “converted from image/jpeg to image/dng, saved to new location”.

Viewing a DNG file this way isn’t the easiest task, and you need to be very careful not to make changes to any of the text and save the modified file, as that can corrupt the image.

If any readers are aware of software tools that streamline the process of determining the provenance of a DNG file, please let me know and I’ll be happy to share that information.