Photoshop Image Size Pixel Dimensions

[fuzzybabybunny]

I've always been confused by this.

In the Image Size window (Image -> Image Size) there are three properties at the top: Pixel Dimensions, Width (in pixels), and Height (in pixels). I have no idea how they arrive at the Pixel Dimensions number. It is NOT width x height.

My current image:

Pixel Dimensions: 748.1M
Width: 51168 pixels
Height: 5110 pixels

Any idea?

 

[Flipped Gazelle]

Isn't the 748.1M the file size?

 

[fuzzybabybunny]

Originally posted by: Flipped Gazelle
Isn't the 748.1M the file size?

The file size is dependent on the type of file and compression. In this case, no. The file is a 1.25GB TIF.

 

[Flipped Gazelle]

Hmm... I opened up a 26mb tif, and under Pixel Dimensions it shows up as 26M. Tif was saved as RGB/16.

I opened up the jpg version of the same file, and under Pixel Dimensions it shows up as 13M. The jpg is RGB/8. This seems to correlate well.

Might not be the files size on disk - maybe the file size in memory?

 

[fuzzybabybunny]

Hmm... could be.

I opened up a TIF RGB/16 with 524.5M as pixel dimensions and 563MB on disk. File size in memory is smaller than file size on disk? I just did an auto contrast operation on it and pixel dimensions stayed at 524.5M

 

[Feanor727]

Pixel Dimension is the size in bytes of an uncompressed per-pixel representation of the image. In other words, width * height * color-depth in bytes per pixel.

EDIT: In your case, 51168 * 5110 * 3 = 784405440

784,405,440 / 1,048,576 = 748.06 ~= 748.1

Check your color depth on that image, I guarantee you it's 24bpp.

 

[fuzzybabybunny]

I gotcha. The reason I ask is because Smugmug only allows a maximum of 48 megapixels for uploads, and there wasn't an easy way to determine this without multiplying out the length and width. But now it looks like Pixel Dimension just needs to be 137.3M or less and I'm good to go.

 

[IronWing]

Originally posted by: fuzzybabybunny
The file is a 1.25GB TIF.

:shocked: Wouldn't it be more convenient to simply carry around the physical subject of the image rather than deal with an image that big?

 

[fuzzybabybunny]

Originally posted by: ironwing

Originally posted by: fuzzybabybunny
The file is a 1.25GB TIF.

:shocked: Wouldn't it be more convenient to simply carry around the physical subject of the image rather than deal with an image that big?

Lake Powell is big 🙁

What's worse is that I'm processing all this on an 800MHz Kohjinsha SH8 laptop. Over an external USB drive.

 

[Flipped Gazelle]

Originally posted by: fuzzybabybunny

Originally posted by: ironwing

Originally posted by: fuzzybabybunny
The file is a 1.25GB TIF.

:shocked: Wouldn't it be more convenient to simply carry around the physical subject of the image rather than deal with an image that big?

Lake Powell is big 🙁

What's worse is that I'm processing all this on an 800MHz Kohjinsha SH8 laptop. Over an external USB drive.

No way!

 

[IronWing]

Originally posted by: fuzzybabybunny

Originally posted by: ironwing

Originally posted by: fuzzybabybunny
The file is a 1.25GB TIF.

:shocked: Wouldn't it be more convenient to simply carry around the physical subject of the image rather than deal with an image that big?

Lake Powell is big 🙁

Yeah, but most folks don't shoot it in macro.