Photshop CS6 image resizing tool.

Question

Five time I have entered a support question but it does not seem to appear in the lists nor have I had a response, am I entering my request incorrectly?
My request is:
I have a PC using Windows 7. I have Photoshop CS6 which I have been using for some time. Very recently the image, image size tool has stopped working. I open the drop down window and the current size of my image is displayed. I then try and type the required changed size in the box but the box does not accept it. The size remains the same. I have un-installed and re-installed CS6 and put in all the latest updates. The first image I tried, it allowed me to change the size. The second image the resize tool would not allow any changes. We were back to where we started. Elsewhere on the support FAQs it was suggested such problems might be cured by deleting \adobe photo cs6 prefs.psp file. This I have done but still I cannot resize my images.
Please can someone help me??

Answer 1

If Photoshop has been working well for you then start acting strange the first thing that should come to you  mind is your Photoshop preferences.  Your Photoshop preferences are Photoshop setting made for your user ID for how you want Photoshop to behave.  Each user ID has there own set of Preference files. These are not installed or removed when you Install or uninstall Photoshop.   So if you un-install and re-install Photoshop your Photoshop preferences remain intact.  If the Problem you are having is caused by a corrupt Photoshop preference file.  You will still have that same problem. Did you try resetting your Photoshop preferences?
Though the Image size dialog is simple many users do not really understand everything about image resizing.  Using a quick look at the image we see three section Top, Middle and bottom..
Top section is basicly image file size how many pixels are there in the image.
Middle Image Print Size.
Bottom Image Resize Image Controls.
To understand Image Resize you must start from the bottom.  In the bottom control section  Resample Image is the single control that governs  the whole resizing process.   When "Resample Image"  is NOT checked all other controls have no roll in the resize process they are grayed out as is the top file size section.  The file size will not change the pixel will not change. Note all that is grayed out in the above image.  All that can be change is the print size.  The middle section and all three sizes there are tied together as shown by the lines and link icon.  Change one size there and Photoshop will calculate the other two and display the proper values. All  thee setting in the center are sizes associated with length.  Width number uints, Height number uints. and Resolution number Pixel/unit. Resolution therefore is pixels size and pixels have an aspect ratio. Most image pixel these days are square 1:1 aspect ratio.  Photoshop support non square pixels but can only display image using square pixels display have. 
So when Resample is not checked. The image has a  Width with a fixed number Pixel, a Height with a fixed number Pixels and Pixel aspect ratio. Setting any one print dimension will also set the other two dimensions.
When resample is check the other controls in the bottom section become useable and so does the top file section.  Normally you should check Constraint Proportions link Width and Height so your image will not distort during the resize. When you resample an image you wind up with an entirely new image with a different number of pixels. Some image quality has been lost for you either through way some details you had or created some details you did not have.  The image quality will depend on the quality of the pixels you had and how well the interpolation method used worker with those pixels. IMO Adobe Bicubic Automatic is not a good general purpose method to it tend to add many artifacts to image that have been sharpened.
In newer version of Photoshop CC and CC 2014 Adobe has redesigned the Image Size dialog adding a preview  image display. Made the dimension link icon the constrain proportion control when resample is checked. Also hid the scale style option under a gear icon in the upper right corner.