Large Prints

[Gothmoth]

Really, the only person who should be worrying about this sort of thing is the one who owns and operates the printer.

well at mpix, adorama, cewe and co. they process probably over a million images a day... who will look at your images and sharpen/resize it?

i tell you : NOBODY.

the resizing will be done by the printer driver.
they will apply a default sharpening for the print size and when you are lucky they give you the choice if you want that sharpening or not.

your advice is a good one for people who do fineart prints and where each image is treated individually.

but i guess that´s not the case for everyone here who wants to print his images at poster size for 6 bucks....!!

so i can only advice people to do their own sharpening and resizing when using a company that does not treat images individually. 

[TrumpetPower!]

but i guess that´s not the case for everyone here who wants to print his images at poster size for 6 bucks....!!

so i can only advice people to do their own sharpening and resizing when using a company that does not treat images individually.

You get what you pay for. If you're buying "fillet mignon" at bulk chuck prices and wondering why the meat is tough as shoe leather and has an off taste to it, I ain't got nothin' for ya.

Cheers,

b&

[justsomedude]

First, can we all use DPI and PPI correctly?  They're being tossed around in this thread incorrectly, and may be confusing to the OP.  Image resolution is defined in PPI - pixels per inch.  DPI, or dots per inch, is a function of the print machine itself, and has nothing to do with the image.  I think most people here are referencing DPI when they mean PPI.  Here's a basic primer... http://www.andrewdaceyphotography.com/articles/dpi/

Now, with that mess out of the way, the method for enlarging/printing varies from printer to printer.  For example, most modern LightJet printers can print images at 150 PPI with no quality loss whatsoever.  I print most of my larger art prints at 150 PPI, which helps a lot with native print dimensions. 

If I do need to enlarge it, I can usually get some significant upsizing from PerfectResize before I start seeing any type of resampling artifacts.  I know one world renowned fine art landscape photographer who shoots exclusively with a 5D Mark II and relies solely on PerfectResize to get his 10' wide prints and larger.  I won't do any name dropping here, but he explained his editing process to me from camera to print (which I have totally adopted), and this is it in a nutshell:

- Import to Lightroom from camera body
- Basic exposure/correction edits within Lightroom
- Export image at 150 PPI with embedded printer profile (I use TIFF at this stage)
- Open in Adobe Photoshop to softproof and enlarge with PerfectResize (if enlarging is needed)
- Perform any final color edits/corrections as needed
- Apply final sharpening within Photoshop (sharpening is always a final step - apply NO sharpening in LR!)
- Save final version as max. quality JPG and send to printer

I have enlarged a photo I took 3 years ago with my 40D to 60" in the longest dimension with no quality reduction whatsoever.  PerfectResize is the schitt.

[Plato the Wise]

First time posting here – but I have been reading for some time now.

I have worked in graphic arts for about 20 years and file sizing for printing is a reoccurring issue. The 300 pixel per inch (PPI) recommendation comes from pre-press work for offset printing. Most commercial offset printing is printed at 150 line screen and the rule is to double the line screen to avoid seeing individual pixels in the print. Hence the 300 PPI.

Dots per inch (DPI) is a completely different measurement and is device dependent. For example, most consumer ink jet photo printers list a DPI output. That doesn’t necessarily mean that you have to match your PPI setting to the exact printer DPI setting to see the best results. Most consumer inkjet printers will print perfectly fine prints at 240 PPI. Lightjets will print great results with a 150 PPI files (for a large format print).

The best thing to do is run tests on the device you are aiming to print on and find what works for you. In the end, the results are subjective and as long as you are not seeing individual pixels and the detail looks acceptable, there really is no reason to create an oversized file.

[dickgrafixstop]

There are several packages on the market as photoshop add-ins that do an excellent job of resampling.
My favorite is Genuine fractals- developed at Pasadena's space lab to enhance data streams from satellites
)think photos from mars) and later made commercially available.  Extensis and Corel both had similar programs
and each was about 100-150 bucks.  I've used them to take low res web files (like gif logos) to put in business
show displays at about 3 feet square with excellent results.  Routinely take 8 -10 meg digital camera files to
print at 24X36 or 30X40 sizes with excellent results.  Photoshop's getting better at resampling, but these programs specialize in it and do an excellent job.