it is concave you can tell by the wrist part of it at the bottom

It is concave, i agree. But still very neat!

actually its extruded, if you look at the wrist the bottom right part of it is brighter, and the other shadows on the right would appear that the sun is coming from the right so its extruding out from the sand

concave
its like coming out the sand you can see the shadow

it is sticking out of the sand but if you try you could sort of see it the other way.

concave. look at the wrist.(good point chris)

I see it as convex, like it is rising to the surface.

Its in cement.

it is extruding as witnessed by the shadows on the thumb and on the pinky side of the hand.

IT is convex. Light source coming from the 3:30 position casting shadow on the thumb and 4 fingers. The slight shadow on the right of the hand is a slight depression before the palm rises.

Looks like it is extruded to me. I'm not 100% though.

extruding from the sand - it looks like someone is pushing their hand thru from under the surface...very cool

the easiest way to tell it's concave is to look at the shadows of the objects on the right side of the photograph. the shadows fall to the right, indicating that the source of light is on the left. if the shadows on the hand were on the right, the hand would be a positive structure instead of a negative structure.

It's Embossed, you can tell by the shadows...

Yeah when you first look at it, it does look convex because of the shadow, but if you focus on the wrist, you can tell it's concave.

It's Embossed, you can tell by the shadows...

it is convex, because of the way the shadows fall, you can see the curve of the fingertips raised upwards,and the shadows fall away from the fingers..

the hand is extruded as the tips of the fingers are casting a shaddow

concave

Visual clues in the image suggest that it is convex, i.e. raised from the surface of the sand.

Assuming this image was taking with a effective point light source (i.e. the sun), observe the shadow patterns on the small rises of sand to the left of the hand, and the dents in the sand to the right. These indicated that the point source is to the right of center of the picture, and below it, and that overall, the hand is raised, casting a leftward/upwards shadow.

This is also consistent with the more rased base of the palm having a brighter lighting than the center of the palm (note the right to left/ south to north darkening gradient).

I think it's convex. If you see the shadow on the thumb, it looks like the sun is shining from the right of the picture.

Also, look how the hand is curved upward (i.e. fingers higher than palm). You couldn't make a concave handprint with your hand in that formation.

Definitely concave. You don't even need the wrist part at he bottom. It "sticks out" at you.

It is both, I agree with "Chris" regarding the wrist, but the fingers are convex you can tell by the little holes in the sand near the right side of the image. If it were all concave the shadows of the fingers would be on the other side.

I agree, its concave... I have a lamp that does the same thing... its of an egyptian pharoes head, and it lookos like it follows you around the room.

its just the way the light is hitting it... the shadow parts where the light does not hit make it look the are protruding.

It's convex: a concave print wouldn't produce the shadow between the little and ring finger...

i agree, i think its concave

Simple. It is and can only be extruded.

i say convex (extruded). why? couple reasons. 1) space between the fingers: there is NO way sand could stay that rigid and be that thin if it was concave. 2) shadowing: the small specks all around are probbaly sticking up, not dipping in. the shadows of the specks seem to match the hand. My mind just cannot picture the hand entruding into the sand with the surrounding shadows as they are.

I see it both ways, so I don't know..
I guess I'm leaning towards concave.

i think it is convex...i can't seem to find a way to see it as a concave hand

I think its totally convex...

embossed- it has a shadow to the left, the sun is shining from the right

It looks convex to me but I suspect that it it actually convex. My brain sees it as convex though.

I see it as extruded

for me it is obviously convex.

Also going for concave (extruding). This is based on how the shadows are cast both from the handprint and the small holes to the right of the picture.

Its an imprint in the sand, look at the shaddows ont he Right Hand Side, these are above the sand.

must be embossed since the light is obviously coming from the right (or that's art of the illusion :))

I believe it's extruded, as when you look at natural embossed holes and marks down the right hand side, the shadows fall on the right.

If the hand was also embossed then the sahdow would also be on the right, but there not. There on the left. Leading me to believe itsticking up.

Hope that makes sense???

it really could be either, the last post is wrong as the wrist could have been done to make people think it was concave.

i think it works coz the human eye believes a thing is extruded when the light falls from the top left.
like the buttons in windows os

just a guess

I agree with chris it is concave. I think it's the shadows that gives it away.

no it's convex. you see how the shadow works in the holes to the right? shadows of the hand are in the oposite direction.

It appears to be convex

it lookes like someone is burried and sticking their hand out from under the sand....
ZOMBIE ZOMG

It is convex. I believe it was made by taking a plaster-of-paris cast and using it as a mold, then smoothing away sand from around the cast.

convexthe
shadows on the tips of the fingers and the palm give it away

Definatly sticking out

Palm prints in the sand do not leave palmar creases, (and if they did they would be raised from the surface whilst all else was depressed). This a a faked image. It could be a palmar caste placed palm up in the sand (its at the level of the last tidal wave limit) which has been embedded and just washed over, its detail makes it unlikely to be an actual palm in situ. It could also have been cleverly sculpted.
It takes very fine powder to pick up palmar creases such as plaster of paris.
Essentially then its raised above the sand.

I agree with saehn...

For it to be concave/embossed/pressed into the sand, the sun must be coming from the left. For it to be convex/extruded/sticking out of the sand, the sun must be coming from the right. Reviewing shadows of other objects in the picture (not connected to the hand), indicates the sun is coming from the left.

Also, there is a slight shadow just to the right of the wrist, which would be inconsistent with a sun-on-the-right, convex hand scenario. It would be consistent with the sun-on-the-left, concave hand case, however, if you account for the slight rise in sand around the edge of the hand, caused by the hand being pushed into the sand.

Extruded

It is concave. The stick on the right side of the picture has the shadow on the right, showing the sun is on the left side castng the shadow to the right side. the shadow on the hand is on the left side. The shadow is from the ridge from the hand being pushed in. Its not rocket surgery!

The hand is extruded. The shadows of the hand do not match the intruded holes in the sand, to the right of the hand.

convex made to look concave

Convex. shadows don't make sense if it's concave.

Look at the shadows. I'm thinking convex.

it looks like its convex, although it could be seen as concave, particuraly if you turn the picture upside down. what it really looks like is that someone partially buried a cpncrete hane in the sand. is it really convex, or concave?

Convex...but sunk into the cement. The hand imprint itself is a convex feature, but the convex feature is sunk a bit into the cement, which explains the extra shadowing around the wrist.

I'm not sure if everyone is using the same definition of concave/convex and embossed/extruded, and I'm not entirely clear anymore either, so I'll use a different term. The hand is imprinted into the sand (or cement). As seahn (#13) mentioned the shadows on the right side give everything away, especially the little wood chip in the top right. They fall to the right, which means the light source is from the left.

It really does look like it's coming out of the sand though, and had the image been cropped it would be an even more convincing illusion.

I'm not sure if everyone is using the same definition of concave/convex and embossed/extruded, and I'm not entirely clear anymore either, so I'll use a different term. The hand is imprinted into the sand (or cement). As seahn (#13) mentioned the shadows on the right side give everything away, especially the little wood chip in the top right. They fall to the right, which means the light source is from the left.

It really does look like it's coming out of the sand though, and had the image been cropped it would be an even more convincing illusion.

the sun is right and the shadow is left so its convex!?? ;)

It's just a picture. You're all crazy. Go read a book or something.

Concave.
There is a blade grass sticking out of the sand(top right) casting a shadow down and to the right. This tells me the sun light is coming from top left.

It is obviously a waffle.

You can see it BOTH WAYS!!!

It appears to be convex, but if you look carefully you can see it concave. Try to imagine to change the light:

If the sun is on the left the hand is printed on the sand...
If the sun is on the right the hand is extruded.

Belive it or not...


clo

It's a hand pressed into the sand, then the photo is inverted making it appear convex.

for me its clear convex... imposible to see it concave... uhummmm?

it is convex....look at the shadows on the fingers

It's Extruding. Good Point Jetuser ^.

Does'nt convex mean out as well as embossed and extruded?. And concave means in?
It looks to me that the Hand is coming from the sand. "Out".

It's actually BOTH! Concave and Convex! Look at the shadows on the surrounding twigs and blades of grass....The shadow casts to the 3:00 position indicating the light source to be at about the 9:00 position. Therefore, the shadowing on the fingers are there simply because they are very deep, Concave. The Palm of the hand however, gradually becomes convex left to right and stops just under the thumb, creating the shadow on the right side of the palm.

Convex - am I right? Ha ha!

I think it depends on where the light source is coming from. If the light source is on the left of the picture, it's a hand print. If the light source is on the right, it's extruded. Thats just my opinion but who knows?

It is concave the sun is coming from an 11 oclock angle. you can tell that by looking ant the piece of wood on the top right corner of the image. and if you look at the hand, the shadow sugests a 3 o'clock if it was extruded but since it is concave it matches the piece of wood

So much ado about a hand in the sand. It is definitely very convincing as a convex or raised
object. I myself have a hard time flipping my brain to see it as it actually is, which is an indentation in the sand.
Look at the small debris to the right, white shells and sticks. They are casting shadows that show that the light is coming from the left of the picture, which would give you dark shadows on the left side of a depression in the sand.
The interesting thing is that either a raised form or a sunken form will look the same, without other visual clues it would be nearly impossible to tell the difference.

actually, it appears to be both. The very edges appear to cave in, and the hand itself extrudes out of the sand. Look at the edges on the left side of the hand. Then look at the edge of the thumb. Based on the comparison of angle angle and the shadows, it seems the hand does in fact extrude.

just tell me!

convex

I see it convex, even if I rotate it. I managed to see the stones on the edge as convex (first they appeared concave), but I never saw the hand concave, which is probably the "correct" version.

The effect has to do with the direction the light comes from. A classical example for this are the craters of the moon. Usually rotating does the trick. But as said before, it didn't work here. Maybe after waiting some time. (The brain is sometimes very stubborn ;-) )

i think its imprinted because of the shadow of the objects on the right side

It's convex look at the rocks surrounding the hand you can see they all have the same dark side as the fingers and hand do and the fingers are casting shadows

I agree with cyberfunk and a number of others: based on the shadows in the sand to the right of the hand, as well as the hand itself, it is extruded. But how was it extruded?!

I once read that these kind of things could be seen either way (extruded or embossed). That we are more used to see things with the light coming from the left, but if we just flip the image it automatically just turns the opposite.

OK...
i get the feeling that it's a real hand covered with sand (or what have you)...
I mean that hand is coming thru the sand - kinda like i used to do as a kid at Muscle Beach (ne: Venice Beach, CA)...
/ch/

I think its coming out of the sand.. hmmm

it looks concave to me

Strictly I suspect that there isn't enough perceptual information to tell - there is no independent way of telling the light source. From one position a convex structure is indicated and from another its concave. Flatly lit stimuli with minimal external information like this generate an ambiguous image that can be perceived according to the viewer's preference. Mine - its flat with black 'shadows' painted on it!

definitely extruding from the sand. the other holes in the sand ont he right side of the image
have shadows that shwo the sunligth coming fromt he right side of the image. The hand, if it was printed into the sand, would show the same shadow patterns on the right side of the hand but it doesn't. Instead the shadows appear ont he left side of the hand where the sun does not hit because of the raised handprint.

it is convex.

I think it looks like someone placed their hand in the sand as they worked on the sand drawing on the right.

It is concave. Notice in the upper right corner of the picture there is a stick protruding out of the sand. The shadow falls away at about 5:00 O'clock. Therefore, the only way for the hand shadows to occur as shown is for the hand print to be pushed into the sand.

While trying to decide if this is concave or convex, I feel that its just flat. That someone did a damn good job using shading and highlights.

it seems.. ..WEIRD!!!

I don't quite get the convex/concave or embossed/extruded (in terms of what?)
I can see the hand in both ways but it is my opinion that the hand has been pushed in to the sand to form a dent. I think that the sun is at about 10 o'clock because of the small protusions (especially the twig like thing at the top) on the right that have shadows falling to their right. The shadows on the hand lie to the left indicating that it is a depression in the sand.

It looks convex, but it is concave. One thing you can be sure sticks above the surface is brown stick in the upper-right corner. (Also the string-like thing a little lower and to the left of the stick) Those show that the light source is from the upper left (about 10 o'clock). So the things which protrude from the surface are bright at 10 o'clock and dark at 4 o'clock. And depressions are dark and 10 and bright at 4. So the hand is a depression. Why does it look like it's raised? I think it's because someone ran a directional embossing filter on the image. That would also account for the grainy effect and other odd artifacts in the picture.

Looks convex to me.

I think it's extruded.

You can actually tell the print in concave because of other shadows in the picture. If you look off to the right, you notice rocks and a small piece of some grass or something, with shadows to the bottom left. From this we can assume the light source is from the top right. Therefore the shadows on the hand are going from a higher surface on the left, to a lower one on the right.

It's convex. There wouldn't be shadows on the inside of the print if it were concave.

But, at the same time, you can look at it as being both. The wrist is raised, whereas, the palm and fingers are sunken in. But, it's definately nore convex than anything else.

If the image looks convex to you just imagine the light source coming from the opposite direction (180 degrees). You can achieve the same effect when looking at pictures of moon craters.

we can keep guessing what it is.. why dont u tell us whos right?

It's concave, pushed in, like movie stars do in front of the Mann Chinese Theater in Hollwood. The sun is on the left. You can tell by the shadow on the pebbles and the stick to the right of the handprint.

This is obviously extruded. You can clearly see it's showdow on the left side of the print. The thumb also casts a small shadow. If you examine the rest of the picture you can also see that the other smaller shadows are facing the same direction.....

I've been studying the image again, and noone has yet mentioned the shadow cast by the "straw" in the upper right-hand corner of the image: it's definitely from the "north-northwest". yet, objects in the center-lower right area seem to be shawowed from the "west".

I think the whole thing is a fabrication, not a "natural" photo at all!

Convex for me

i think that it is contruded. it is a mix of both worlds.

Post some new illusions man. Its been so long. and do post this!!!!!!!

The hand is going in (=convex).
On the upper right there is a small wooden thing coming out of the sand. It's shadow is to the right, indicating that the light comes from the left.

The hand is going in (=concave). On the upper right there is a small wooden thing coming out from the sand with its shadow to the right, indicating that the light comes from the left...

Looking at the stick in the upper right, it would appear that the light is coming from the left. This makes me believe it's convex.

it looks convex. if it's concave, it's great work by the illusionist.

It's convex. If you see the little holes on the right of the picture, you can see their shadows to the left, which means that the sun is coming from the right! And if you see the hand, it also has shadows on its left side! It's coming out of the sand! Case solved!

It's concave.
See the tiny bit of wood, top right corner? Its shadow goes to the right... So the hand can't be convex.

it's definately convex.

convex

EMBOSSED

I would have to go with concave, it seems as if the back of the hand is being imprinted in the sand.

Convex in my sight, Extruded.

If the light is coming from about 3:30/4:00, it hits the wrist which is lighter, and the shadow falls past the fingers

I don't see any way to see it as Concave unless you look at it and think the finger tips are laying in shadow rather than the shadows laying past th