hi. i always face this problem that i am using adobe photoshop cs4 . when i create psd and make a jpg file than i get that my jpg file size is too much. 90px X 30px may be about 120kb. i think this is too much. so i want to make this lighter with great quality. so what is the best way to make jpg file size low. without loss image quality. i get a image 1600px X 550px this size is only 27.5 kb. so how can i make my image size low..
Image optimization is not always the same. You should try other image types like gif and png. You'll probably notice that you have better ratio of quality / size of the file depending on the type of data contained in your image.
Usually, if your image has a limited count of colors, gif or png8 will give better results. If your image has a lot of colors, jpg or png24 are the best options. But watch the compression noise when you use jpg.
Best trick I can give you is : use save for web and compare file size / quality with different settings. You can have up to 4 comparisons in the save for web window. Photoshop "Save for Web" option is the best way to export your images for Web use.