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Jens
2013-Nov-15, 08:49 AM
This is something that's bothered me for some time. When I first got my iPhone, one of the things I downloaded was a "mirror" application. Well, basically what it does is, it uses the camera to film you and then reverses the image. Which is OK, but actually I really was hoping to have an app that make it feel like you were looking into a real mirror. There's something different about the experience, but I'm not really sure what it is. Usually when you see illustrations of mirrors, it shows them with stripes of darker and lighter areas, so maybe it's a non-consistency or something. Does anybody know what you would have to do to a "mirror app" to make it seem like you were looking into a real (flat) mirror?

Nowhere Man
2013-Nov-15, 11:44 AM
About the cheapest "mirror" app I can think of is to turn the device off. The black glass makes a passable mirror. :)

One problem might be that the camera is off center. Another could be that a mirror produces a 3D image, while the device does not. Yet another could be the small lag between your movements and when they appear on screen.

Fred

Shaula
2013-Nov-15, 12:19 PM
I'd also guess lighting is a factor - the reflected light from the mirror and the projected light from the screen are going to change your illumination and colour balance subtly.

Strange
2013-Nov-15, 01:10 PM
Also, the source of the image: you can look yourself in the eyes in a mirror but not in a mirror app like this.

Squink
2013-Nov-15, 02:11 PM
Image contrast is usually lower on iPhone than mirror. That'll give your face the unrealistic look of a videotaped 80's soap opera.

NEOWatcher
2013-Nov-15, 02:13 PM
What about focal length? Wouldn't that also throw in some "warping" of the image?

Strange
2013-Nov-15, 02:26 PM
Also, limited dynamic range and noise (especially in low light).

Interesting question, by the way.

Jens
2013-Nov-15, 11:47 PM
Also, the source of the image: you can look yourself in the eyes in a mirror but not in a mirror app like this.

That's something I hadn't thought of but it's probably a big factor. When you move you lose sight of the image, but with a real mirror it moves with you.

Amber Robot
2013-Nov-15, 11:53 PM
Usually when you see illustrations of mirrors, it shows them with stripes of darker and lighter areas, so maybe it's a non-consistency or something.

What are these stripes you are speaking of?

Jens
2013-Nov-16, 03:28 AM
What are these stripes you are speaking of?

I'm not sure if I'm describing it correctly, but when you draw a picture of a mirror in Photoshop you draw a gradation pattern or draw lines with a pencil to make it look like a mirror. If you google for mirror and look at image you'll see what I mean.

Jens
2013-Nov-16, 03:47 AM
Also, limited dynamic range and noise (especially in low light).

Interesting question, by the way.

Thanks. It's one of those simple questions that probably has pretty deep answers. I started simply by wondering why I can't find an app that feels like a real mirror, but I'm also wondering why mirrors are drawn the way they are in illustrations.

Solfe
2013-Nov-16, 04:06 AM
When drawing with black pencils, there are several conventions for depicting complex shading. Hair is a great example because it has many colors and textures. In theory, you could draw every strand of grey hair in black, but you would destroy the idea of color. Dark haired people could be drawn the exact same way, but it tends to be tedious and less than representive of the person. A half way point showing structure is much easier on the artist and the viewer.

I draw glass, metal and mirrors with a series of lines on them to impart the idea that it has a color or texture that is not entirely solidly colored or visible through the glare or reflected light.

profloater
2013-Nov-16, 09:39 AM
drawing a mirror is a convention. Many real old mirrors do distort straight lines as does old glass so I think the convention of wavy lines stems from that. True mirrors show perfect reflections but even modern mirrors distort when seen from a distance. The experience of looking at a picture rather than a reversed mirror image is strange because we all have our assymetries.

publiusr
2013-Nov-16, 07:44 PM
My mirror image always looks uglier the farther away I am from it--and the voice I hear when I speak is better to me than a recording--if only there was an app for all that...

Jens
2013-Nov-17, 12:39 AM
The experience of looking at a picture rather than a reversed mirror image is strange because we all have our assymetries.

Have you ever tried one of the apps I'm talking about? They do reverse the image to make it like a mirror, but still it seems different.

I was shopping yesterday and had the chance to look at a lot of mirrors. One think I noticed is that there is a striking loss of depth perception when I close one eye, that seems much more striking than in the real world. So with the camera apps there is a lack of depth, which is probably another factor.

Jens
2013-Nov-17, 02:50 AM
I just realized a huge difference, at least with the iPhone. The image is much smaller than the one I see in the mirror, even though I'm holding the camera closer than I am to the mirror.

profloater
2013-Nov-18, 10:54 PM
There used to be an old joke, the mirror reverses you left to right, why are you not upside down? You can still see a frown of bafflement cross many faces with that one.

Amber Robot
2013-Nov-18, 11:07 PM
Put the mirror on the floor and it will flip you upside down. :p

Jens
2013-Nov-19, 01:18 AM
There used to be an old joke, the mirror reverses you left to right, why are you not upside down? You can still see a frown of bafflement cross many faces with that one.

I wouldn't consider that a joke, more like a puzzle. What's interesting is, I think that actually the mirror doesn't reverse you. Up is up, down is down, right is right, and left is left. I think it's actually the photo that reverses you. If you want to look at a photo facing the same direction as you, you have to turn around. And there are two ways to turn around, one is to turn sideways (which reverses left and right), and the other is to stand on your head, in which case you flip up and down but leave right and left the same.

Nowhere Man
2013-Nov-19, 02:35 AM
A mirror reverses front and back. A photo reverses front and back and left and right.

Fred

Trebuchet
2013-Nov-19, 03:10 PM
I was shopping yesterday and had the chance to look at a lot of mirrors. One think I noticed is that there is a striking loss of depth perception when I close one eye, that seems much more striking than in the real world. So with the camera apps there is a lack of depth, which is probably another factor.

Right. Mirrors, for people with binocular vision, are 3D. Photos, no matter how good, are 2D. (Unless it's some sort of 3D camera, of course.)