0

If one is having large prints made by a professional printer (say, 3' square or more), does one...

(1) ...take care of the enlargement in Photoshop (upsampling to necessary dpi in raw before outputting to tiff)? (I'm using CS6.) Or...

(2) ...give the printer the photoshop file with the raw image in it? Or...

(3) ...something else?

Thanks to you all, as always!

  • Do you imply that you do not need to do anything with RAW image at all? – Euri Pinhollow Mar 25 '16 at 17:44
  • Hello! I will have done some work with the RAW image, yes. Cropping, certainly. But possibly potentially more destructive things (although I tend to use smart objects for those) - rotation, for instance. Possibly other work as well. I will definitely have done work on the images. – Wombat Pete Mar 25 '16 at 17:49
  • 1
    If you send the printer the raw file most of the non destructive edits you did may or may not be applied. If the printer opens the file in an application other than the same one in which you did your work all of your edits will almost certainly be lost. Export your edited raw file to something like a 16-bit tiff and then worry about whether you want to resize it yourself or let the printer resize it. Even if you are working in Photoshop with a raw file, by the time Photoshop upsizes the photo it is working only with the information contained in a tiff file. – Michael C Mar 25 '16 at 22:23
1

The most important step of preparing prints is soft proofing: previewing how limitations of printting gamut affect the image. To do this you need profiled display and ICC profile from the printer which will be used.

Regarding resizing: if you want to exclude any resampling done by printer you may want to resize to the maximum resolution. Two options:

  • resize with method "nearest neighbour" - this will keep your data almost intact if your photo resolution is few times lower than actual printing resolution
  • resize with any other method (bicubic, bilinear, etc) which you prefer to improve details - you may choose any, try all of them. Just kepp in mind that no method will inprove resolution, resizing may only affect the appearance of details.
  • The calibration/profiling part I understand. As for excluding resampling by the printer - I thought a professional printer might have better enlarging software means than are available to me. If not, then - you're right, certainly, better to control as much of the process as possible. – Wombat Pete Mar 25 '16 at 19:33
  • But I shouldn't have to worry about the printer profile, should I? Wouldn't the print shop take care of that? – Wombat Pete Mar 25 '16 at 19:34
  • 1
    @wombat-pete: "I thought a professional printer might have better enlarging software means than are available to me." - I'd be not worried by this. Doing and editing photos during past years tought me that best technologies available are almost always done by enthusiasts, high cost technics MFGs are not interested in best results. – Euri Pinhollow Mar 25 '16 at 19:40
  • 1
    @wombat-pete: regarding profile - your print shop will of course use profile for printing, but the way in which it cuts the gamut and affects your image (not because profile is bad, but because it is impossible to do it perfectly) will be unknown to you. – Euri Pinhollow Mar 25 '16 at 19:42
1

You want to send all the data to the printer.

If you have a 1000 x 2000 pixel image, there is no magic way to get a decent 3 foot print out of it.

Most prints are viewed at a distance where they take up a certain angle of your vision. You don't hold an 8x10 3 inches from your nose. So if you have an image that looks good at 8x10 at perched on the corner of your desk 3 feet away, then it will look good at 30x40 10 feet away.

The situations you watch for:

People will be closer than normal to your pic. e.g. in a stairwell, elevator, bus shelter.

People will be moving closer to examine part of your image. Tech photos, forensic photos, some kinds of art photos.

People will be much further than normal from your pic. Billboards, sides of semi trailers, bus wraps.


Most colour printing is done on a halftone grid of about 130 lines per inch. Now in halftoning you vary the size of the dot, but not its colour. So a rule of thumb is that you need about twice the pixel resolution as halftone screen frequency. So most people figure that 300 ppi is enough to get good pictures. These are ones that will not be obviously printed at normal viewing distances. (Some publications, like National Geographic use much finer halftone screens than this, and do as many as 8 colour separations. Newspapers on the other hand use 75 or 90 lpi halftoneing. Newsprint makes the ink run, so a higher frequency just makes for muddy looking prints.)

Go up close to a billboard. The halftone dots are sometimes 1/2 to 3/4 inch across.

Anyway: A 3 foot image is 36 inches. If you are going to view it close up, you want about 10,000 pixels If you are going to be viewing it from 10 feet away, 3000 x 3000 pixels is enough.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.