i clip an image in 8.5 "x11" standard paper size. and want to write on it. do i have to place any other rectangle behind it? so that the printing guy wont have ny problem to print it? or writing on the clipping masked image will be enough! i just need to know....
TLDR: Do not rely on masks, rectangles or any other graphic elements to indicate print area. To prevent erros, select the appropriate page size in document settings.
I used to be the printer guy and received all kind of files and formats to print. The best advice about error free printing is "information, information, information". You have to tell every detail about what you want. If the art is sent by a website form, use the comments field. If it is sent by email, write the instructions instead of just attaching the file. Write instructions on the file name, like "poster - 8.5x11 no resize - CMYK - Portrait.PDF". Select the appropriate/correspondent page size in the document. Do not rely on masks, background rectangles or random lines to indicate the print area, it is confusing. If it is extremely necessary, write instructions on the final art itself, OUTSIDE the print area and if you have any other questions, ask the printer guy if more information is needed.
In most cases, white (especially in a background) is read by printers as "no ink" and so what you leave white on a design will end up the colour of the paper, as it gets "knocked out" in the printing process.
If you stop and think about it, this makes sense: if you were printing on white paper, anything white in a design would be created in the print via not inking that area - so by extension, if your chosen bond is a mid-brown craft paper, the white design areas will end up craft paper brown in your final product.
As to creating false coloured paper by laying down that colour or tone in a background shape - this will work only if you are then having the paper trimmed to remove the portion left un-inked by the press or printer - despite all advertising indicating otherwise, there is still no printer which truly prints edge-to-edge, so anything requiring colour to the very edge is created by setting what's called int he industry a "bleed" - that is, a distance BEYOND the edge of the artboard and beyond the printing area to which you extend all colour fields or images intended to be at the very edge of the paper.
The printer then trims down to the new edge, and your colour field or image now goes right to the edge - or "bleeds".
This of course requires the raw print to be done on a larger sheetstock and trimmed to the appropriate size, so you then pay for the labour to trim and the original paperstock size used to create the final product.
It is true there are specific special conditions in which white may actually be a colour of ink or toner explicitly called for - but this is an atypical workflow relative to the vast preponderance of prints - and bluntly - spot colours, separations, Pantone definitions and so on are the province of the industry of professional graphic designers and print shops - of which you clearly are not part.
I hope this helps clarify things a bit - I am really unsure that I'm answering the question you intend, as it's very unclear - but based on the comments thread you have with Scott, I think this might help.