Open Radar

 
Summary: 
When printing a document in Preview.app, the default value from 'Scale to Fit: Print Entire Image' can be used even after 'Scale' has been selected and an explicit value provided, if the user changes to another page (such as 'Layout' or printer specific option pages) after specifying the scale value.

Steps to Reproduce:
1. Open a document in Preview.app, such as a PDF that has an object of known dimensions.
2. Select 'File' > 'Print…'
3. Verify that your printer and paper settings are correct.
4. Note the default value in the scale % box (this is greyed out), which needs to be other than 100% for this to (not) work.
5. Select 'Scale:' instead of 'Scale to Fit:'
6. Enter '100' in the scale % box. Do not press tab or enter.
7. Select 'Layout' from the 'Preview' drop down menu.
8. Return to 'Preview' from the 'Layout' drop down menu.
9. Note the value in the scale % box now reads '100 %'
10. Click 'Print'
11. Measure the object on the printout, and calculate any percentage difference in size from the expected size.
12. Repeat steps 2 through 10, but on step 6 _do_ press tab so that the dialogue updates the value with the % symbol.


Expected Results:
Since both print scenarios show a scale value of 100%, the actual printout should be as close to 100% as a simple 'ruler and eye' measurement is able to show, and should be identical.

Actual Results:
The printout from step 10 prints scaled to the 'Scale to Fit:' 'Print Entire Image' scale percent. The second printout from step 12 does print at the correct scale.

Regression:
I have a Canon MP630, however have heard of other printers exhibiting this problem.
This bug did not exist for me in any version of OS X 10.5.x.
On the apple discussion boards, gnomehost's post references this problem ( http://discussions.apple.com/thread.jspa?messageID=10268615#10268615 )

Notes:
Not all testing possible has been done, but as far as I can tell the key to getting this bug to appear or disappear seems to be hitting tab after entering the scale value. It is also possible that there are other ways to make it appear, as I was having a lot of difficulty pinning down when it was occurring, exactly. In my particular case, I was printing DVD faces, so any misalignment was immediately evident. Since the setting was on the first page of settings, I would often enter the correct scale value then move on to set other print options, this was a common problem to have occur.