Simplified automated duplex margin repositioning system for different size originals

A simplified automated process for producing duplex printed copy sheets of a selected two dimensional sheet size from original document sheets of a two dimensional sheet size with at least one dimension of said document sheets which is different from said copy sheets, so that said duplex copy sheets will have substantially equal margins from the image areas in at least one margin in one dimension on both sides of the duplex copy sheets irrespective of said different sheet size of said original document sheets from said copy sheets, which original document sheets are imaged at a two axes registration position on the imaging platen of an imager for input to a duplex reproduction apparatus for printing said duplex copy sheets on opposing sides with images of two said document sheets, which duplex reproduction system also includes a control system for image position shifting of the image printed on said copy sheets, and for storing information as to the known size dimensions of the selected said copy sheets;

• said automated process further comprising:
• registering a first original document sheet of a first sheet size at said two axes registration position on said imaging platen for said imaging thereof,
• removing said first original document sheet of said first sheet size from said imaging platen after said imaging,
• registering a second original document sheet at said same two axes registration position on said imaging platen in the same orientation as said first original document sheet for said imaging thereof,
• measuring at least one dimension of at least one of said first or second original document sheets to automatically determine at least one said dimension of its sheet size,
• automatically subtracting said known size dimension of said selected copy sheets in the dimension which includes said margin from the corresponding said dimension of said original document sheet to determine a desired duplex image shift dimension,
• and operating said duplex reproduction apparatus control system for image position shifting of the image printed on said copy sheets to shift said image of said second original document sheet on said copy sheet by a distance corresponding to said duplex image shift dimension to produce said duplex copy sheets with substantially equal margins from the image areas on both sides of the duplex copy sheets in at least one said dimension irrespective of said different sheet sizes of said original document sheets from said copy sheets.