Terminology for an "optical RGB image" in relation to more complex imagery like hyperspectral imagery?

Question

I am currently writing the literature review portion of my dissertation and I find that I am being quite wordy when attempting to describe what a layman would conceptualize as an "image". That is, an optical RGB image, for example a picture of a dog. Specifically in relation to other forms of electromagnetically sensed imagery like multispectral, infrared, and hyperspectral imagery.

Throughout my work I make the distinction that electromagnetic radiation collected by an imaging sensor produces imagery. That imagery can be of a specific type e.g. multispectral, infrared, hyperspectral, optical RGB, etc. But I also wish to refer to the common conceptualization of a "plain old picture image" that anyone would understand.

To do so I have found myself using the term "optical RGB" quite often, it's the only terminology that seems to describe "a plain old picture" in relation to the other forms of imagery described.

Is there a better term I could use in this context to switch between the corpus specific imagery and layman specific image?

Example of usage: "The surfeit of research in deep learning aimed at semantic segmentation of optical RGB images naturally lends itself in applications to hyperspectral imagery"

Answer 1

Adding the acronym RGB doesn't help much. There are plenty of images to be found that are RGB but represent spectra we can't normally see with our unassisted eyes. Example The Horsehead Nebula in new light shows said system in the far infra-red, using RGB.

My suggestions

visible-spectrum images**

or

visible-light images**

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** Of course, even these are vulnerable to criticism because different creatures see in different ranges of the spectrum. You need to make a definition of your term somewhere and then stick to it. Maybe define HVimages to mean human-vision-images.

Answer 2

Dictionary definitions of visual relate to the seeing of something

relating to seeing

something such as a picture, photograph, or piece of film used to give a particular effect or to explain something

Cambridge dictionary

Definitions of optical relate to visual but also tend towards extra aspects relating to the use and science of light and optical science.

used in order to see something better

connected with the eyes or sight, or connected with or using light

Cambridge dictionary

of or relating to the science of optics

Merriam Webster

I therefore suggest that a layman would understand "visual image" as something to be seen with the eye, but that "optical image" would imply something about the technicalities of light, sight and optics (as does your own "optical RGB", which might even be incomprehensible to the lay person).

Furthermore, visual image is still reasonably defined within the wider spectrum of images that you are writing about so may not conflict with your technical text.