Rendering Settings – DPI vs. pixels

Had a question today on how to set the DPI settings for PhotoView 360…

Good question – not really sure…

Off to the SOLIDWORKS Knowledge Base…

Bottom line?  There is no way to set the DPI in PhotoView 360 (or PhotoWorks for that matter).  The concept of DPI is only relevant to printing, not on-screen images.  

Here is the SOLIDWORKS solution that explains it all…

Solution Id: S-02581  

Question:

Regarding the PhotoWorks/PhotoView 360 image resolution, rendered output is always 96 DPI, even if set much higher in PhotoWorks/PhotoView 360.  Why?  

Answer:

If the user checks the file properties of their rendered image in Windows, they will see 96 DPI.  This value is saved in most bitmap images, and is generally irrelevant to image processing.  DPI is actually meaningless when referring to on-screen images, these are defined purely in number of pixels.  PhotoWorks allows input of size and DPI settings to help the user generate an appropriate size image.  The following settings would all give an identical output:

20in x 20in at 50 DPI

10in x 10in at 100 DPI

5in x 5in at 200 DPI

1in x 1in at 1000 DPI

These would all produce an image of 1000 x 1000 pixels, with identical file size and detail – the files would be indistinguishable. 

Where the DPI setting is useful is if the user knows he/she wants to print an image 6 inches x 4 inches at 600 DPI, SOLIDWORKS can take this information and calculate that it needs to render an image size of 3600 x 2400 pixels.  The user can experiment with this by inputting a size and resolution in the Render to File dialog, then switching back to Pixels to see what size image will be generated.

Nathan Brunner, CSWP

Technical Analyst

Computer Aided Technology, Inc.