Is it possible to tell how old a digital picture is?

Question

My photos teacher wants us to take a recent photo of ourselves for a project [recent meaning within the last few days]. i cant get a photo of myself that i like that's not 'younger' than about 2 months old..i dont like so different but she said something about being able to test it by it's pixels?

is this true? i dont know if shes trying to scare us or not..

Answer 1

If she has the actual file, the data embedded into the file can be easily viewed--with a computer. The data can be edited, or removed, but it does not sound like you have the program to do so.

If you have an actual print of a photo, then she won't be able to tell by looking at the photo--again, I don't want to assume that you are not understanding this, but I have to say, the actual paper photo in her hand. Unless you were taken holding a copy of LA Times dated 2nd January 2005 or something.

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She's sneaky. But you can circumvent any of her tricks by printing that photo onto a photo paper, then scan it with a scanner and save it into a JPG file. It won't have a trace left of the data from the camera.

Unfortunately it's like a cat & mouse game and the rule is that it must be < 2 months old--and to be honest, you're breaking this rule. You could end up getting a bad grade from this--so I really don't suggest it.

Answer 2

Every photo taken by a digital camera is emedded with additional data called EXIF. The EXIF data contains a bunch of information such as the camera make and model, aperture, film speed, shutter speed, etc., etc.

One of the fields is Date Taken, which is the date the picture was taken.

The easiest thing to do is open your photo in photoshop or a similar program and resave it and get the program to strip out the meta data.

If you don't have  a program that does that, or don't know how, here's what to do.

Open your picture in an image editting program (like photoshop).

Select the entire photo and Copy.

Create a new blank image that is the same size as your photo, and Paste the image in.

Save the file as a jpg.

This will save your photo, but none of the meta data will be saved. Now, there is no way they can tell when the photo was taken.

Answer 3

It just gets worse.

The EXIF data is stored on each file ...

Here is a program that will allow you to look at all the data that is collected at the time it is captured.  It is called OPanda.

Here is a sample of what your instructor will see when she checks.  You will see, if that data has been removed or modified, it will be suspicious.  

[Image]

Make = NIKON CORPORATION

Model = NIKON D300

Orientation = top/left

X Resolution = 300

Y Resolution = 300

Resolution Unit = inch

Software = Ver.1.00

Date Time = 2008-06-28 00:15:13

Artist = Your Name

YCbCr Positioning = co-sited

Copyright = Copyright 2008, Your Name, All rights reserved.

Exif IFD Pointer = Offset: 312

GPS Info IFD Pointer = Offset: 8984

[Camera]

Exposure Time = 1/250"

F Number = F5.6

Exposure Program = Manual

Exif Version = Version 2.21

Date Time Original = 2008-06-28 00:15:13

Date Time Digitized = 2008-06-28 00:15:13

Components Configuration = YCbcr

Compressed Bits Per Pixel = 4

Exposure Bias Value = ±0EV

Max Aperture Value = F3.61

Metering Mode = CenterWeightedAverage

Light Source = Flash

Flash = Flash fired, compulsory flash mode, return light detected

Focal Length = 20mm

Maker Note = 8020 Byte

User Comment = (C)2008,YourName 8884441234    

Subsec Time = 0.86"

Subsec Time Original = 0.86"

Subsec Time Digitized = 0.86"

Flashpix Version = Version 1.0

Color Space = sRGB

Exif Image Width = 4288

Exif Image Height = 2848

Interoperability IFD Pointer = Offset: 8938

Sensing Method = One-chip color area sensor

File Source = DSC

Scene Type = A directly photographed image

CFA Pattern = [R,G],

[G,B]

Custom Rendered = Normal process

Exposure Mode = Manual exposure

White Balance = Manual white balance

Digital Zoom Ratio = 1x

Focal Length In 35mm Film = 30mm

Scene Capture Type = Normal

Gain Control = High gain up

Contrast = Normal

Saturation = Normal

Sharpness = Normal

Subject Distance Range = unknown

[Interoperability]

Interoperability Index = ExifR98

Interoperability Version = Version 1.0

[Thumbnail Info]

Compression = JPEG Compressed (Thumbnail)

X Resolution = 300

Y Resolution = 300

Resolution Unit = inch

JPEG Interchange Format = Offset: 9108

JPEG Interchange Format Length = Length: 8780

YCbCr Positioning = co-sited

[Thumbnail]

Thumbnail = 160 x 120

[MakerNote (Nikon)]

Makernote Version = 0210

ISO Speed Used = 6400

Quality = FINE  

White Balance = FLASH      

Focus Mode = AF-S  

Flash Setting = REAR        

Auto Flash Mode = Optional,TTL      

White Balance Bias Value = 0, 0

White Balance Red, Blue Coefficients = 432/256, 295/256, 256/256, 256/256

000D = 00, 01, 06, 00

Exposure Diff = 9E, 01, 0C, 00

ThumbOffset = 8026

Flash Compensation = 00, 01, 06, 00

ISO Speed Requested = 6400

Photo corner coordinates = 0, 0, 4288, 2848

0017 = 00, 01, 06, 00

Flash Bracket Compensation Applied = 00, 01, 06, 00

AE Bracket Compensation Applied = 0EV

001B = 0, 4352, 2868, 4352, 2868, 0, 0

001C = 00, 01, 06

001D = 3065083

001E = 1

001F = 30, 31, 30, 30, 01, 01, 00, 00

0020 = 1

0022 = 0

0023 = 30, 31, 30, 30, 53, 54, 41, 4E, 44, 41, 52, 44, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 53, 54, 41, 4E, 44, 41, 52, 44, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01, 00, 00, 02, 80, 83, 80, 80, 81, 80, FF, FF, FF

0024 = FE, 5C, 00, 00

0025 = 84, 01, 0C, 00, 01, 04, 84, 01, 0C, 00, 01, 04, 00, 00

Lens Type = Nikon G series Lens

Lens Min/Max Focal Length, Max Aperture = 180/10, 2000/10, 35/10, 56/10

Flash Used = 7

Bracketing & Shooting Mode = 0

008A = 1

008B = 40, 01, 0C, 00

Lighting Type = NATURAL    

0091 = 30, 32, 31, 30, 0F, 6F, 32, 83, 17, B3, 6E, 51, 59, 86, D8, 4F, EB, CF, 92, 9D, CD, 22, 9C, 34, FF, EC, F6, 20, 81, F8, A0, 67, AC, 9B, 61, 24, 75, 1A, E6, 72, E7, 20, 7F, 78, A9, 76, 68, 7F, 3B, 0B, 85, 4D, 1C, 82, 2D, 24, D5, 98, 03, 05, D1, EE, 30, 97, 23, 42, AA, B7, C5, 0A, 74, 03, B7, 90, 8E, B1, F9, 66, F8, AF, 8B, 8C, B2, FD, 6D, 02, BC, 9A, 9F, C8, 16, DF, 21, DE, C0, C7, B3, 04, FA, 75, 35, DA, 44, 73, C7, 40, BE, 41, 69, 16, A8, 9F, 58, C5, D6, AD, BC, 72, B3, B2, 91, 6A, 22, F7, 70, AF, 54, 07, C3, B5, CA, 07, 65, EA, 6F, A3, 52, B0, 50, 8D, 9B, 9A, 02, CF, D6, 78, D1, A9, 0D, E3, DC, 3C, 3E, 8D, 36, E9, C1, BE, E0, 27, 93, 24, DA, B5, B4, DB, 24, 93, 24, E3, CF, 6F, 75, BD, 28, 48, 95, B9, BF, 58, 5C, 75, 6D, 00, F0, 61, B9, 69, EB, 20, 8A, 02, 63, CC, 15, 9A, 13, CA, 4B, 70, FD, C4, D3, 65, 1A, D2, 3C, 16, 32, 6C, 0C, 45, B0, D6, DF, AF, 21, 16, A8, D7, 61, 9E, 03, 87, 33, D8, FA, CD, 55, CC, 44, 85, C7, CF, DF, 67, 89, 14, C8, AD, 9B, BD, 02, 7C, FD, B3, 8C, 8A, AF, FA, 66, F9, BE, 76, 31, 36, 03, 74, 0A, C5, A5, AA, D4, DD, 97, 30, EE, D1, 27, 98, 58, CF, 6B, 24, 12, 1D, B2, 5D, E7, 6A, 7F, 68, 74, 08, 01, 7E, 21, 9E, 2C, 1B, E4, EB, F5, 9A, 64, 53, 67, A0, FE, 81, 29, F6, E8, FF, 3B, 9C, 22, CD, 9D, 91, AC, EB, 4F, D8, 86, 59, 51, 6E, B0, 17, A3, 54, 2A, 25, 44, 88, F7, 82, 35, 13, 0F, 33, 7A, E6, 78, 2F, F4, F3, C9, B6, ED, 82, 3E, 56, 1F, 48, 97, 75, 5E, A1, BB, 8D, 73, C4, 38, 8E, 95, 7A, 85, 38, F8