I have a
5760px x 3840px image with a filesize of
I would like to reduce its filesize to
200KB without altering its dimensions.
How can I do this in Photoshop?
This could be achieved by using the function "File>Save for Web..."
In the upper right corner you can select a preset and the file type. If you select JPEG and go with the settings in the picture above, you will get a small resolution picture with the same dimensions. You can play around with the settings and in the bottom left corner you can see the current size of the image. (My picture is now 4.669KB)
Hope this method will also help you in the future because you can do this for any image type by just selecting a different one in the upper right corner!
If you're saving the image as a JPEG you could lower the quality setting until you get your optimal file size.
This can significantly affect the visual quality of your image though so it all depends how you want your final image to look.
This probably is not possible, especially for a non-uniform color field (e.g. a photograph).
In terms of raw image size without compression, you are dealing with a minimum of 5760 x 3840 bits.
An RGB image of this size, filled with uniform noise and saved as jpeg with "worst possible quality" compression is 16MB.
One thing to try which hasn't been mentioned is in the Save For Web dialog, if you click the Menu in the upper right corner you can choose
You and then input your desired file size and Photoshop will do it's best to get there. Be prepared though. A 1000% reduction in file size is going to result in an image of absolutely horrible quality.