This is a fun experiment I love doing with my B&W vidicon cameras, especially with my 1970 Sony AVC-3200CE camera. In late 2002 was checking out a section on Richard's Labguysworld video technology site called "Color pictures from a B&W Quickcam?" and I was amazed at his results and I thought to myself, "Hmmm I wonder if I can produce a colour image from my AVC-3200CE camera? So I carried out my experiment with the same procedures as Richard but as I didn't have professionally made dye filters, I decided to try my luck with red, green and blue cellophane wrappings as RGB filters and the results were amazing, I managed to accurately reproduce a colour image!!! Below is my first successful colour image:
Now I am going to share with you the process I used to create my colour images from the 40 year old B&W vidicon camera. I hook up my Sony AVC-3200CE to a DVD recorder or a VCR, set it to record to capture the video and I shoot a still subject or scenery with preferrably no motion and place the red, green and blue cellophane pieces in front of the camera one after the other to filter each primary colour. I generally use 2 layers of each colour but for the green I experimented with 2 and 3 layers as it looked lighter. Anyhow once the video is recorded, I burn the footage to a rewritable disc and copy it to my computer and open the VOBs in a video editor. From there I export video stills from each section I used a primary colour, one for the red, one for the green and one for the blue. Then I open the stills in a photo editor and convert them to greyscale 8 bit and I use the combine channels function, select the RGB and assign each filtered B&W still to each primary colour and voila, a colour picture!!!! The picture is dark as the colour filters have filtered out a lot of the light as well so the brightness, contrast and intensity needed to be adjusted, I just used an auto levels adjustment to achieve a reasonably bright picture and it also auto level the colours as well. From this point I should have a decent colour picture, I may do some further tweaking to the colour and the luminance settings to improve the look of the image if it doesn't meet my standards. Overall I end up with a decent colour picture. I created a YouTube video demonstration of what I explained which has pictures and video clip to further illustrate the process which can be seen below:
Here below is the RGB filter process applied to reproduce the colour bar test pattern displayed on my monitor, you can distinctly see the difference in each colour filtered B&W image:
Red filter: the colours in the pattern that are rich in red primary colour are brightened
Green filter: the colours in the pattern that are rich in green primary colour are brightened
Blue filter: the colours in the pattern that are rich in blue primary colour are brightened
The resultant colour reproduction of the colour bars from combining the above RGB channels and the luminance ramped up
Here below are a number of colour video stills I've made from the RGB filter process with success varying from poor to pretty good depending on the amount of light, for moving objects the colour phasing problems are evident:
I have made a further development to this colour experiment. As I was noticing how good and clear the unfiltered B&W images are and was thinking about the colour reproduction process in a RCA TK-42 colour camera in which it used an extra image orthicon tube for good luminance levels in combination with 3 vidicon tubes for each primary colour, I thought I'd apply the same principle to my colour experiment to improve the quality of the image especially those low light shots.
Basically what happens when placing colour filters over the camera lense, not only am I filtering the colours but I am also darkening the image, so I felt I needed to bring back the luminance and sharp detail to the image as I noticed the unfiltered B&W shots are nice, bright and crisp so I decided to take a still of the unfiltered B&W shot for the luminance channel. Next step was to superimpose the combined dark colour image over the crisp bright B&W image which I did using Adobe Photoshop. I copied and pasted the colour image over the B&W image and I blended the layers using "colour" as the blending setting, then I merged the layers together. This gave a brighter image with colour, though the colours were pretty desaturated. So the next step was to ramp up the colour saturation which I did which resulted in a nice bright colour image, not perfect mind you as the picture is a bit grainy which gave the confetti speckle effect on saturation, but a much more improved brighter colour image when the luminance channel was added. I did some little tweaks here and there to the luminance and the colour balance if I felt some improvements to the images were needed to meet my standards, but apart from that the results are excellent!!!
Here below are 3 pictures of some colourful bottles in front of my microwave, one with without the luminance channel added and one with the luminance channel added, and a 5 megapixel mobile phone camera snapshot. The improvement of the colour image with the luminance channel added over the image without is evident. I've added the 5 megapixel digital snapshot to compare the accuracy of the reproduced colour still from the B&W vidicon camera with that of a modern digital camera shot.
Reproduced colour image without luminance channel, the image luminance level and colour saturation was adjusted to closely look to that of the image with the luminance channel. As seen a very grainy green tinged picture.
Reproduced colour image with luminance channel added requiring only colour saturation adjustment and minor luminance adjustment. The quality of the image is greatly improved with better clarity and less grain and much less green tinging.
Below are a few colour stills I made using the newly improved RGB channel filter plus luminance channel process:
5 megapixel mobile phone camera shot of the coloured bottles, obviously 1000 times more superior quality than that of the colour images from the vidicon camera, however goes to show the accuracy of the colour reproduction from my 1970 B&W Sony camera using cellophane colour filters is pretty damn good!!!