Optical Illusion: Create One With Any Color Photo

Intro: Optical Illusion: Create One With Any Color Photo

This instructable will show you how to take negative afterimages to another level. By introducing a negative color photo and then immediately incorporating a black and white version of the same photo, you will perceive the black and white photo in full color (the way the color photo was meant to look). This can be done with any color photo!

If you've ever seen negative afterimage optical illusions, you know that they can be baffling and sometimes quite spectacular. They often involve staring at a negative image for 10-20 seconds and then looking at a blank space. The usual result is seeing what some call a "ghost image" of the negative image, yet it is seen as a positive image (i.e. the way it is supposed to look). These are a well understood retinal phenomenon.

This is a very simple project, yet it is extremely effective. The way that our eyes and brain perceive and interpret images allow for us to trick ourselves in this case. After viewing this over and over, the same effect happens each time. It can be frustrating in terms of trying to figure out why this illusion happens. Ultimately, it is my hope that you will find this helpful, intriguing, and boat-loads of fun!!

Here is a video of the completed project which shows the optical illusion in its entirety:

STEP 1: What You Need

You will need:

1] A color photo file
2] Photo editing software that allows you to:
a) "invert colors" or create a "negative image" (almost all programs out there, including Paint, have this feature)
b) make a black and white version of the photo
3] Video editing software (this is optional but very helpful in yielding the best results)

STEP 2: Choosing a Photo

I highly recommend using a photo that has rich colors and a lot of contrast. This will stimulate your eyes more and ultimately enhance the effect of the optical illusion.

STEP 3: Creating a Negative Image

Import your chosen photo into a photo editing program. Then simply choose the "invert" (or "negative") editing option. This should convert the whole photo into a negative image. Then save it. Make sure that you keep the original color photo that you imported, if you want it. For instance, I used Photoshop and saved the inverted photo as a copy. I still retained the original photo.

Now, just like that, you have created the first part of the illusion.
Let's move on.....

STEP 4: Creating a Black and White Image

Now that you have a negative color photo, it's time to create a black and white version of the original color photo. To do this, import the original color image into your editing program again. This time, just create a black and white version. Again, save it as a copy if you don't want to lose your original color picture file.

STEP 5: Optional Focal Point

You probably noticed a dot near the center of the photos. This just provides a focal point that you can stare at in order for the full effect of the illusion to work.

It is not entirely necessary. Without it, you can just choose a point near the center of the photo to stare at. The important part is to stay "zoned in" on one spot near the middle of the picture.

If you decide to add a dot in your photos, use a drawing tool in your software to make a small white circle (see picture). Obviously when you invert the original color photo, this dot will be black. That's what you want.

STEP 6: Bringing It All Together

Now you have all of the photos that you need. Here is exactly what you want to do:

1) Stare at the focal point of the inverted/negative color image for about 15 seconds.
2) Have the black and white photo appear, seamlessly, immediately after that 15 seconds.
3) Continue to stare at the focal point after this transition. You will see the black and white photo in color (unless you are colorblind)!
4) Keep your eyes on the photo, but switch your view to another part of the picture. Stunningly, you will see that it is black and white.

A video editing program is really helpful to use with this illusion. Just import all of the pictures into the editing program, except for the original color image. Drag the inverted/negative photo onto the timeline first and stretch it out so that it plays for about 15 seconds. Then drag the black and white version of the original photo onto the timeline and place it right next to that. Dont' get fancy and use any transition effects in between here. Just let it switch to black and white instantly. The amount of time that you keep the black and white photo playing is up to you, but I let it go for about 10-15 seconds or so.

Again, here is the full effect of the illusion in living color (or at least it appears to be):

Comments

[JulianQ]

[killerdynamo]

These illusions never work for me. I blame the colorblindness

[Puzzledd]

This is a fabulous trick- so easy (I don't have Paintshop, but just used Microsoft Picture Manager, and set colour saturation to 0 to get the greyscale image- took a couple of seconds). I used a colourful picture of birds- great purple after-image!

Thanks for this 'ible- and a really good explanation, too :)

I'm off to find some more colourful pictures to use!

[Puzzledd]

Um, actually that should be -100 for the Hue setting. I also raised the midtones a bit in the B&W version if it was a bit dark.

This picture has the best results of those I tried. You just focus on the dot on the peacock's tail near the centre. The colour effect is quite dramatic.

[greeenpro]

I'm glad to see that you experimented with this and are excited about it. That's really cool!! Caution: this process can be addictive...hahaha. Thanks for your comments.

I was checking out your featured ible about the 40 something uses for old CD's. That was a GREAT ible. I subscribed :)

[Puzzledd]

Hmmm... I love taking photos, now that they're digital, and virtually free- and I do like finding different things to do with all those photos sitting in my computer... I have a few fun things already, maybe I should do a guide or an Instructable on them...

Too many ideas, too few hours in the day:P

Oh well, one day...

Thanks for your comment and for subscribing, I do hope to do some more soon!

[greeenpro]

"Too many ideas, too few hours in the day:P"

So, so true. I'm stil waiting for a time manipulation instructable. Anyone? Please?

[Puzzledd]

:D

[peacemaker5000]

cool i had to watch the video again and not look at the dot just to see if you faded in to black and wight 

[eulaliaaaa!]

If you look at it after it changes you can see that the image Is black and white.

[eulaliaaaa!]

WOAH!  THAT IS NEAT!

[Caspar]

It's not really an illusion, it just looks like one.   ;-)

[Lance Mt.]

What would happen if you used 2 different but very similar.

[greeenpro]

Good question! To my knowledge they would have to be almost identical if they were different. The reason being that, in a sense, the negative image is retained by your brain as you stare at it for 10-20 seconds. The illusion occurs when the same picture is then suddenly presented in black and white. The details or objects in both pictures need to be the same or, again, almost identical for the effect to work. I would like to try it with very similar pictures, but I think it would be a waste of time. I don't think it would work. If you happen to try it, please post a response here with your results.

[Lance Mt.]

I am trying as wqe speak. So far i've done one which almost worked. The picture showed up which coloured the face in oddly which was what i was going for, however it was not very effective on the dark image

[greeenpro]

Ok. That's what I was afraid of. If I understand you correctly, it doesn't really work when you switch to a different black and white picture.

[Lance Mt.]

It works on the light sections and not as effectively as the dark sections. When i switched back i had bright explsoions and grey dirt. However it works, most pictures work. Cheers

[greeenpro]

Thanks for the reply. Your research is very interesting. I'm off to try it right now! Thanks again. Cheers

[Infinitevortex]

Fantastic video! I didn't realize I was looking at the B&W image unll I looked away. Perhaps you could modify it for the "Teach Me Fast Video Contest"

[greeenpro]

I thought about that. It would take a minor miracle to pull off a thorough 30 second video on how to do this (actually you are only alotted 28 seconds because of the Forbes.com logo that has to be displayed for 2 secs.). To explain how to do it and present the illusion would take too long since you need to stare at the negative image so long. Thanks for your comment/compliment!!