I have created vector art in Illustrator 5.5 that is exported as a PNG file at 96 dpi. When we open the PNG file in Photoshop, the image size is larger in Photoshop than it is in Illustrator. Width was 232.8 px on Illustrator document and 233 on Photoshop document. Height was 181.4 px on Illustrator document and 183 on the Photoshop document. If I export as a 72 dpi PNG file then the size does not change. How can I export the image at 96 dpi without changing the size of the image?
The png file format does not contain ppi information and the interface of the Export options were not programmed intelligently enough to make sense.
So, you have to specify the generated raster images with the desired pixel dimensions and not ppi. For example 300 pixels wide by 200 pixels high and not 100 ppi for artwork with 3 inches wide by 2 inches high.
Create you artwork with the desired pixel dimensions in Illustrator and export at Screen resolution. If you want to generate an image with different pixel dimensions, an easy way is by choosing File > Save for Web and Devices and use the Image tab to change the dimensions.
If you have to use File > Export, then choose a ppi number that will make the desired pixel count when multiplied by the inches size of your artwork. Blame Adobe for not allowing you to just type the desired pixel dimensions in the Export options but making you calculate them in this stupid way.
I am building vector art for an interactive math program. We were asked to create them in Illustrator and export them as a PNG. Under PNG settings window we were told to check other and put 96 for the dpi. I have a maximum canvas size for these images. We also have art that has to be a specfic measurement so it is important that the PNG image stay the same size as the illustrator image. We have started uploading the images into the program and we noticed the problem. The files ended up being wider than the canvas, so we went back to the AI files and measured them there and saw they were the correct size. Then we went an took a look at the PNG files and noticed that they were larger. I understand that we can use File > Save for Web and Device and they will keep my image size the same, but saving the files that way would create images created at 72 dpi. I can also export them at 72 dpi and keep the image size the same. I'm not sure how to create them using the 96 dpi setting and keep the image size the same. I might need to go back to the customer and ask if we can create the images at 72 dpi since that would solve the size issue.
Actually, I was wrong about the png file not supporting ppi, originally it didn't but Adobe had added this support later. In my experience however a lot of programs still do not read this information.
Regardless of this, the instructions given to you do not make any sense. The only way to keep the pixel dimensions the same is to choose the Screen (72 ppi) export option in Illustrator. Then you can make this file 96 ppi in Photoshop. Choose Image > Image Size, uncheck the Resample image box and change the Resolution to 96 pixels/inch then save the file and it will remain 96 ppi.