Image Size

Hello,

I'm having a problem with image sizes being correctly displayed (see the 2 attachments).

In the folder view/details it shows as 586kb, but when opened in Photoshop the file reads as 1.90M. A huge difference.

So is this a system error, or am I missing something?

(Btw, I'm working between a Mac & PC, so not sure if that's affecting anything).

Hello & welcome to the forum - I suspect that PhotoShop by reporting a 1.9 MB file is giving you the original size of the RAW or JPEG image from your digital camera (assume that was the source?) - I have a 16 MP Panasonic Lumix which saves as LARGE JPEG images (yes, MB range).

Now if you have manipulated the image, i.e. cropped, resized, reduced resolution (pixels/inch) and then saved, the compressed JPEG size would be much less. Now I've not used PhotoShop in several years but have a number of photo apps on my MBPro & iPad, all seem to report the metadata & file dimensions slightly different. Dave

Hi Dave,

Yes, the images were from a digital camera. That data shows in the view window, but why is the size wrong?

Here's another example (see attached image) where the metadata shows it as 551kb, but when opened in Photoshop it's over 6.5 Megs! To make matters worse, if I hover or right-click the properties, it reads as 1.02 Megs.

3 different sizes for 1 image. Crazy. Am I supposed to open hundreds of images in order to find out what each real size is?

Photoshop shows Pixel Dimensions, it is not the same as File Size.

Don't worry - everything is as it should be

File size will depend on the format you're going to save the image in, pixel dimensions, broadly speaking, will remain the same.

Working file size, particularly if you set Photoshop to remember, say 20 steps, can be many times the actual image size.

This may also be a Windows thing as well as what you've shown us are a set of discrepancies as they get manifested on a Windows box. Does the same thing happen on your Mac?

David - I understand about the pixels, but a 250kb image is not something I would, automatically, send to a printer for a large poster. I would consider it a small web graphic. But I'd be wrong, unless I opened it in Photoshop to discover the truth....

Vansmith -- good question. I haven't checked on my Mac yet, but I (also) suspect it has something to do with these frustrating PCs...

facimag said:

David - I understand about the pixels, but a 250kb image is not something I would, automatically, send to a printer for a large poster. I would consider it a small web graphic. But I'd be wrong, unless I opened it in Photoshop to discover the truth....

Click to expand...

Sorry, you've lost me there - you're still confusing two different things.

Like I said, Photoshop shows Pixel Dimensions, it is not the same as File Size.

If you need to know the FILE SIZE, look at image properties in your OS' file manager and forget, what you see in Photoshop. I suspect that file size is your main concern, right?

facimag said:

Vansmith -- good question. I haven't checked on my Mac yet, but I (also) suspect it has something to do with these frustrating PCs...

Click to expand...

This has nothing to do with the operating system used, I can post Linux screenshots to prove, but you just have to trust me on this

Hi David,

I did more research and you're right: the pixel dimensions are different than size -- which can fluctuate depending on the saved format. And when opened is PS, can often triple (which is why a small file gets suddenly huge).

I'm not used to raw camera files; I usually work with already compressed JPEGS, so that when I see hundreds of them in a folder -- and sort them by SIZE -- I know immediately which ones were saved down for Web and which are high-res.

Anyway, thanks to all for the time and help. Much appreciated!

No worries, glad you've managed to put your mind at ease.

I did actually run a little test on the same file, as handled by three operating platforms, using Photoshop CS2 in XP, GIMP in Linux (both in VirtualBox) and Photoshop CS5 in OSX - surprisingly, GIMP is the least confusing - it reports the actual file size, pixel dimensions and the file size in memory as three different items, can't be clearer. If only Adobe ever paid any attention ... to anything or anyone.

Even if the image dimensions are the same, the file sizes can vary on the amount of data in them. Thus a black and white image will have smaller size then a photo of a rainbow.
Also size of the data on disk is not the same as file size once in memory. The file can be 500k on disk, but once opened up it can take up to 2MB or more. This is completely normal.


I have a few panoramic photos on my system that are over 13,000 x 8,000 pixels at 240PPI.. That takes quiet a bit more RAM.. LOL