How to save

[mónicam21966108]

When I save a photo the file gets small
Please help

[Dynamic Office]

You’re going to have to be WAY more specific for anyone to be able to help you,

Which OS are you using?

Which version of PS are you using?

What file type are you saving as?

What is the file type the original image?

How are you saving?

[mónicam21966108]

Hi.

I'm using macOS High Sierra Version 10.13.1
I'm using the last version of Photoshop (updated today) PS CC 2018
I started with a raw file, then I wanted to save the file as jpeg
I already tried to save in different ways and the file always gets small, from a 146MB psd i get an about 3-4 mb jpeg file.
If i open the file in Photoshop and do IMAGE - IMAGE SIZE - the file is almost 49 MB
Please help
I don't know what to do

[Test Screen Name]

That sounds normal. JPEG is used Precisely because it makes smaller files. Do you see a quality problem? What quality setting do you use in save?

[mónicam21966108]

Hi
I'm using quality 12.

[Dynamic Office]

RAW files are compressed files, but are “lossless” – that is, they lose no information in compression. Generally speaking, a RAW file will be three to four times larger than the same image shot in JPEG, not in dimensions, but in megabytes. So this is why you’re experiencing the file size decreases.

JPEG image is a compressed image, and that in the process of compression, a very small amount of information is lost.

[mónicam21966108]

I don't think that's the problem.

The size of the jpeg is more then 10 times smaller
One exemple, from 39.90MB the PSD file to 3.25MB the jpg

[Derek Cross]

What's wrong with that?

[mónicam21966108]

Usually the files don't get so small. I have the felling that something is not right

[Per Berntsen · Accepted solution]

The file size of a jpg will vary greatly depending on image content, and is not an indicator of the quality of the image.

To assess the quality of the jpg, open it in Photoshop and compare it to the original at 100% view. (assuming that the jpg has the same pixel dimensions as the original) When saved at quality 12, you will probably not see any difference.

Consider the two jpg images below.

The first one has large flat areas, which compress well, resulting in a small file size.

The second has lots of busy detail, which does not compress well, and the file size is almost four times larger than the first one.

Both images were saved using the same quality setting.

41 KB

146 KB

from a 146MB psd i get an about 3-4 mb jpeg file.

If i open the file in Photoshop and do IMAGE - IMAGE SIZE - the file is almost 49 MB

The operating system will report the real file size (146 mb?), including extra layers and channels.

Photoshop will only report the file size according to the pixel dimensions, without extra layers and channels, and without any compression.

You may find these articles useful:

What is a digital image?

File formats

[Test Screen Name]

What is the image size in pixels?