printing confusion

[jainamishra]

<p>Hello everyone,<br>

<br />I do not know much about printing and leave that aspect entirely to my printers when we print poster sized images. <br>

<br />This time, a client is handling the printing directly and they are facing the following problem:<br>

<br />My file size handed over to them is around 2400 x 3000 pixels at 300 dpi. This translates to about 20cm x 26 cm document size. </p>

<p>Let us say that this has to be printed in the size 80 cm x 120 cm. </p>

<p>Their printer has come back to them saying that the file size that I have given them is not enough and I should give them larger files. (This has created a slight delay in the project as I am travelling, am on slow internet and cannot upload files that are 70MB each.)</p>

<p>The only way I know how to make my original files larger is through Photoshop -> Image Size and change the values and get a larger file. </p>

<p>I doubt that my solution is the correct one, because surely the printer couldn't be serious about sending the whole batch back for reprocessing and creating a delay for a solution as simple as the one I am suggesting?</p>

<p>But I really do not know any other way. Even my RAW files are no larger than 3000 x 4000 so how would that suffice for this print? </p>

<p>Please help.</p>

<p>Jaina Mishra</p>

<p> </p>

[jaydesi]

<p>If you enlarge the originals, it's the same as if the print shop printing them at lower resolution. If you gave them the largest files you had, there isn't anything you can do to give them "bigger" files...they should use what you gave and enlarge appropriately. The larger the print, the further the viewing distance.</p>

[Matt Laur]

<p>A quality printer is going to have better software than you have for increasing resolution. Fractal-based tools, for example. Posters aren't meant to be seen from three inches away - they should be able to work with what you've given them, once they hear from you that you understand the compromises that will present in this case.</p>

[jainamishra]

<p>Thanks Jay & Matt. Will communicate this to them.</p>

[Wouter Willemse]

<p>Jaina, what Matt is aiming at is that many posters aren't printed at 300 dpi, but lower values. Because you watch from a longer distance, the "pixelation" that will happen in the print becomes less and less noticeable. Large billboards, for example, can seriously go down to 5~10 dpi. You will never see up close how incredibly huge those pixels are, so it's fine. Take your 3000 pixels at 200 dpi, and suddenly you have 5 inches more already...</p>

<p>If your posters do need to be sharp and not-pixelated up close, then check indeed with your printer if they have good tools to increase the resolution without too noticeable loss in quality. Else, the only other solution is getting higher resolution originals (stitching multiple images, for example, could be a solution).</p>

[jainamishra]

<p>Thanks Wouter for demystifying this. Now I understand the math (I think).<br>

<br />In this case we have no choice but to work with the existing files as the shots are all from travels and it is not possible to reshoot. </p>

<p>Jaina </p>

<p> </p>