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Five different colour spaces viewed on screen with similar points compared - an experiment. Purpose:  To view the results of looking at a common image on screen with different colour spaces. Materials:  A jpeg image with widely varying colours and a PC computer running Photoshop CC (26) Method:  Take a jpeg from a raw photo showing a wide variety of intense colours.  Apply different colour spaces to the image and compare swatches from the same area.  Colour spaces used, pallets include as it was originally converted from a raw file, Adobe RGB, sRGB, CMYK, and for the Epson P800 set to premium luster paper. Results:  The 5 images above with labels indicate the selected areas of the common image used to compare colour spaces.  A colour swatch was collected using the eye dropper tool and the resulting colour was then deposited in a rectangular box table seen above.  Looking with the eye, the colours are very similar.  Closer inspection using Pho...

The colour yellow is difficult to print or display on electronic media. I have noticed over the years that yellows don't always come out with the brightness or level of detail that I would expect.  It seemed to me that yellows would hit a wall when it came to how bright they could get.  That never seemed to be a problem with the other colours.  To prove this to myself, I took an image with bright yellows and broke the colours down into their CMYK counterparts and looked at the levels of the colours.  You can see the results below. Yellow-rumped warbler.  Notice cyan and magenta hit the left wall on the histogram and stop, but yellow goes past the wall.  This is because the file is not capable of rendering yellow to that level. Upon researching the concept further, I discovered that there is truth to the concept.  It seems that the ability of the human eye to see yellow extends past the gamuts of print, film, and electronic media.  Another problem ...

Houseboats in Victoria, BC.  Taken in 2020 with my Panasonic FZ2500 bridge camera. How, exactly, do digital cameras capture colour?  We know that the digital sensor is the physical device that receives light in the form of an image from the lens, but how does that translate from photons to pixels?  The answer lies in photo cells arranged in something called a Bayer array.  See the image below. A 20 mp sensor has 20 million pixels, each pixel is made of 4 wells that provide colour data. The Bayer array is the backbone of the digital imaging industry.  Although there are other ways of getting coloured pixel information, this method is by far the most commonly used.  The sensor does not produce an image directly.  Rather, that job belongs to the camera's CPU, where the information is processed into whatever file type is selected.  Jpegs, as mentioned in a previous blog, use 8 bit per channel encoding, where a value from 0-255 is assigned for each of ...

I made a print of this and sold it to the owner.  I used a pigment-based multi-cartridge printer. If you have a photo you want to print, there are numerous options.  You can send it out to be printed or print it at home.  There is the traditional photo print with light-sensitive paper, using a colour laser printer, ink/bubble jet, or the dye-sublimation printer.  Each of these has its own advantages and disadvantages, including cost, quality, colour gamut, and convenience. Light-sensitive print:  With few people doing their own darkroom work, traditional photo printing is now done throughout labs.  You print digital images through web-based photo services such as Nations Photo Lab , or you can take your images directly to a store that allows you to upload to a print service, usually in the building, like London Drugs .  The colour gamut tends to be less than what you can get out of a good home printer.  The advantage is that you don't need any eq...

You can be sure to be met with smiles and helpful salespeople when you walk into The Brick.  Eager to make a sale, the people there will no doubt approach you with all the professionalism and knowledge you would expect from Leon's parent company.  And, once they have convinced you to buy their products, they will offer you an opportunity to purchase an extended warranty. You may hesitate at the expense, until they tell you that, "If you do not use the extended warranty, you may return to our store and put that money towards another product."  Ergo, it ultimately costs you nothing to have an extended warranty.  It sounds like a win-win situation.  Pay for something, then get it back later and put it towards something else.  Like many others have done, we thought it was a good deal, and we fell for it. What they don't tell you is that the day the extended warranty ends, you have 90 days to take them up on their offer.  However, they are not likely to tel...

The colours here may not represent the actual colours from the scene.  Screens and prints do not have the same broad ability to display all the colours of the spectrum.  The range is the colour gamut. What is a colour gamut (also called a colour space)?  Essentially, it is the entire set of colours that can be displayed on media.  Although there are millions, even trillions of colours available in a file or print, they do not represent every single colour originally present.  Even our eyes are limited in that there are colours they cannot pick up that exist in nature.  The colours that we can see are the visual colour gamut.  The ones that can be seen in print or electronic media are other colour gamuts. How many gamuts are there?  In Photoshop, there is an almost unlimited number.  To see the list in Photoshop, Click on the top menu View > Proof Setup >  Device to Simulate > and then look at the list - there are hundreds of cho...