No worries.....not angry at all.....just trying to be clear on whats going on.
Lets back track a little and try to get on the same page.....bear with me...I'll make it as simple as I can.
For the time being forget all about resolution...
I see the problem you are having as being different images sizes....ie in PIXELS.
The same 'object', lets say for instance a car door, may occupy all of the available space on say a 1000px square image.....the door touches all four sides of the canvas.
Now lets say you get the same image from another client on a 3000px square image....the door still touches all four sides.
If you use your script on those images then you WILL get different results.....as you point out there will be many more pixels per 'door' in the larger image.....so your Measurement calculations will reflect that.
IDEALLY you want the 'object', (the car door), to occupy the SAME amount of PIXELS regardless of image size.....and preferably at a size that relates to your 'scale' (85px / cm).
Unfortunately this is something that only you can do manually.....if you know the dimensions of an 'object' then you have to scale, (using transform or other method), or resample the image so that the amount of pixels / object fit with your scale.
No script can do that for you as only you can interpret what you see in the image as an 'object'.....PS just sees a whole bunch of greyscale squares.
I see you having two options...
A: Resample or transform each image to 'fit' your scale of 85px / cm....OR....
B: Set a new scale based on the image you are working on....and SAVE it for future use.
I don't see how you can have "one scale fits all" when the image dimensions could be completely different from one another.....after all the whole idea of having a 'Custom' scale is precisely for this reason....that images come in different sizes and the 'objects' in those images could occupy any amount of pixels.
Either way I think your stuck with manually measuring each image and setting your custom 'scale' for each one....do you get dimensions on these images?
When it comes to printing the resolution only needs to be 72ppi to keep your printer people happy......but you'll have to be careful to get the scale correct for each 'object' you put in it....or whatever you do with your calculations.
I've probably just confused you even more now but the intention is good.....honest.
Regards.
MrToM.
