How a Pixel Gets its Color | Bayer Sensor | Digital Image

[Amurov1]

Now that's one hell of a MIND JOB, right there!!! Thank you!!!

[Brandonsk33n]

Very, very, very well stated. Made it simple enough that I assume a 6th grader would know what's up. But detailed enough to start a conversation =D

[ccricers]

@pepnacho65 Here's some math ahead: properly converting a color image to grayscale takes advantage of the fact that human eyes are more sensitive to green than blue and red.

To get the grayscale value you compute the dot product of the original color and 0.3, 0.59, 0.11 representing the three colors in a 3-float vector. In other words, green gets the most weight and blue gets the least. Those three numbers are approximate values.

[arbanaskocudo]

great presentation

[niyodavid20]

perfect explaination. thank you very much!

[ManGotSkillz]

WHat the my brain to small to learn this!dafadfsdsdgs

[NGJenkins]

TERRIFIC!!!



[averredude101]

wow man this is the best learning video!!! Im not good with intuition but you did it!

[thai2708]

thanks

[roborovskihamsters]

love the way americans say "awwkwa" instead of "aqua".

[samasjacaj]

Thumbs up if of Montreal brought you here

[vivek2675]

sme useful stuff....nice...watch it...njoy it

[malfoy261]

very helpful, thanks :D

[mimeywimey]

Our teacher explained this to us in 40 minutes, you did in 6 minutes. You sir are a win and deserve a pixel mushroom that Weebl uses

[fvxLaRage]

great video man! you must be from california non? or oregon haha. hey i was wondering why is there a difference between colors in light and colors that we paint with or see on objects. im super confused about this

[SprDrumio64]

Why don't sensels use Yellow instead of Green, i know you just explained it but wouldnt Yellow be more practicle, i mean it is a primary color.

[Jazztpt8]

sensors make a lot more sense now

[fogster31]

michael is the new youtube god

[meowtrox]

How about the "WHITE BALANCE" - SHIFT how does that affect my image? i see this CROSS "GRID" on my settings, etc.

and what about if i shoot in RAW mode? will it sacrifice some colors? because it's not on JPG?

[pepenacho65]

Wow, your videos are amazing!

question: why do the sensel uses more green than red and blue? is this arbitrary or has a reason?

[ccricers]

@pepenacho65 The reason green is used more and in fact the reason those three colors are chosen actually relates more to the structure of a human eye. They have cone cells that are like the "sensels" our eyes and well they react best to those colors. So we are just following what is already part of our anatomy.

The cells that respond to green light are the most sensitive so electronic displays tend to use more components for green colors.

[walliswizard]

Fantastic video, perfectly clear.

[hellian145]

Thanks for this video, it was well put together and you used a great example with colors of water.

[hellian145]

@G3org3eMaster

Same, I've had so many mis-calculations in C++ because of that principle.

[G3org3Master]

You said it was 256 each but in photoshop its 255, why?

[MichaelTheMentor]

@G3org3Master because it starts at 0, not 1.

[G3org3Master]

@MichaelTheMentor ah yeah, thats anoyying cus when programming I always get confused cus you have to start counting from 0 not 1.

[robertwc82]

yellow is red + green? yellow is a prime colour. yellow + blue make green but yellow can not be made by mixing 2 colours

[MichaelTheMentor]

@robertwc82 You are thinking about CMYK, not RGB

[robertwc82]

@MichaelTheMentor CMYK?

[MichaelTheMentor]

@robertwc82 Yes, Y is a primary color in the CMYK color model -(Cyan, Magenta, Yellow and Key, which is Black) It is used primarily for printing. Very easy to see where the confusion comes in. The recording of light on a digital sensor in most cases is using RGB as described on the video.

[StoneAgeAbortion]

@MichaelTheMentor

Revolutionary but Gangster?

[TheWebkinzSurfur]

@robertwc82 The video is saying about light which is RGB you are saying about pigments which only reflect or absorb which is CMYK. Think of this, No blue light in yellow so when you mix it makes white because yellow is R + G and you add blue so it's R + G + B. But for pigments yellow does not contain red so it makes green. Look for Light Theory and Pigment Theory OR Color Theory. or buy for your child (if you have) Flashlight Color filter and Finger Paint ;)

[Turtlena315]

Just curious how does red and green make yellow? is there a different color system or something?

[buckheadcreative]

@Turtlena315

Read Effa's response below...the pigment color wheel is very different from the light color wheel.

[LeoReaper21]

Only one word: AMAZING. *0*

[dbc1987dbc]

Is his colour theory right? Don't red, yellow, and blue make up the primary colours and green is a product of yellow and blue?

[EffaBuse]

@dbc1987dbc :It's right.The RGB system wich is an addative color-system. If you have no intensity in any of the colors it will be black, full intensity for white. Think of RGB as 3 lights (red, green blue) that together make the color. It's used in TVs lcds etc. Use a magnifying glass on your TV and you'll see it.

The CMYK color system is subtractive. If you mix all colors it will be black. Cyan (looks light blue/turquise) and Yellow makes a green color. This is how printers and paint works.

[miqveh]

If there is a higher number than 5 to give as a rating value....I'll pick 11

[mquirozt]

Could you explain pros and cons between Bayer and Foveon sensors? I learn a lot of your Bayer explanation, great, thanks ...

[ecaep45]

cooooolllll

[Ebooknetworking]

I was looking for the meaning of "CCD" This is a brilliant Pixel Tutorial -Thank You

[renzshigeno13]

nice!! i learned a lot..

[spongebens]

you, sir, are just brilliant! wish my teachers are even half as effective as you are.

subscribed!

[c2thew]

awesome video

[bubbleglass]

thanks for this :)

[ObiTrev]

I'm currently working on a project that requires a red, green, and blue sensing photodiode. Not wanting to spend a lot of money, I'm buying three standard photodiodes and covering each one with either a red, green, or blue film.

Do you know where I could purchase rgb plastic films?

[seraphinapandora]

Awesome, awesome, awesome!

[Tuesdayjade]

That was so helpful! Thanks so much!

[Conker714]

lmao 5:48 - 5:55

nice tutorial I actually learned something useful for my work with photoshop

[emailme4861]

Michael you are a Maven!!!

I've known for a long time that a picture is combined of R.G.B but didn't know how its done

so thanks very much!

P.S. you have great teaching techniques

[hjelme83]

ive been doing photoshop for a few years and just got into taking pictures. and this were all new information for me. Learned sometihg new :D

[ler0np0]

Darn! Science seems to have revised. Just decades back we were taught in a science experiment class that light is made up of 7 colors. This was even demonstrated by shining a flashlight through a triangle glass prism and then projected to sheet of paper.

[AgentOrange409]

The color spectrum contains 7 colors: Red, Orange, Yellow, Green, Blue, Indigo, and Violet. (a.k.a. Roy G. Biv)

A digital camera is capable of processing 256 shades each of red, green and blue light for a total of 16.7 million possible colors.

[ler0np0]

The color spectrum nowadays was reduced to 3 colors: red, green and blue as demonstrated in Photoshop. You don't need the 7 rainbow essence colors anymore to reproduce back sunlight or white light.

[12thDecember]

That is *very* interesting. I can see now that by adjusting the values of R and G and B in an editing program such as PhotoShop, that critical colors will be accurate and I don't have to rely on eyeballing my monitor. I can correlate them with an external aid such as a color wheel or chart that gives the respective values for the color I want.

Great presentation of your material. Thank you.

[daluke61]

Although I'm familiar with much of the subject material on your YouTube site, there were more than a couple "Oh wow, I didn't know that"'s. LOVE your teaching approach and styles, very impressive!

Thank you Michael... a dvd or two are on my get-list!

[Benjamin5050]

Thats a really good video.. also a good way of showing it woudl be to use the adjustment layer "channel mixer" as it would reflect your glass demo perfectly

[oisiaa]

Very informational video.

[gotecki]

Great video!

One thing which might be obvious but it's not emphasized is that the actual "megapixels" resolution of a digital camera sensor refers to the luminance, the colour resolution is less than 1/3 of that (reds are even less than that) due to the bayer matrix interpolation.

Only the Foveon image sensor can capture 1 colour information per pixel.

And some Sony CCDs have a 4 colour bayer filter (with an additional aqua sensel, instead of two green sensels).

anyway, thanks for sharing!

[ravi48819]

The video says that nine sensels are used to represent a pixel.

But according to Wikipedia "Bayer Filter" entry, each individual sensel (Red,Green, or Blue) represents a pixel and the missing color data of each sensel is gathered

by interpolation( e.g., neighboring pixel).

Which is correct?

For example, would a 5 megapixel camera contain 5 million sensels or (5 million X 9) sensels?

[gotecki]

a 5 megapixel camera will contain 5 million sensels.

Wikipedia is correct.

[ravi48819]

OK

I am not sure what the video is referring to at 02:35 when it describes the nine sensels required to represent a pixel...

Maybe it's saying each sensel represents an individual image pixel, but that the value of every sensel is calculated by the value of neighboring pixels.

[MichaelTheMentor]

Yes that is right. The words are carefully chosen. Its not 9 sensels represent a pixel, its nine sensels are involved in the calculation of a single, central target sensel and contribute their data to determining the final color. This is simplified with 3 sensels (the glasses) instead of 9.

[MichaelTheMentor]

The video and wiki are both correct. A 5 Mega pixel Camera has 5 million pixels, however, the final color of each pixel is interpolated by its neighboring pixels, otherwise it could only be pure red, pure blue or pure green. Each sensel does indeed represent a single pixel, but to determine its color, it needs help, 9 sensels are used in the calculation of a single, central (meaning the one in the middle) pixel.

[surferboy36O]

Hmmm.... that would be..... why?

I thought a "pixel" was the 16.7 mill color capable unit (like in a tv or monitor), weather its made of 3,4,6 or 9 elements, so a 5Mpix camera would have 5M times 3 or 4 whatever individual color cells (sensels I guess).

In the calculation your talking about one final pixel would share information with its neighbour (softening the transition). On the other hand it would be space saving.

[arpanbhagat]

another great video ... thanks michael