going to be printing a pano, what settings should I use

[tayl0124]

Okay I am going to try to print a pano that I took the other day. The printer requires/suggests jpg format. The current file is 66.071x9.108 at 240dpi.

My plan it to print it out on a 20x30 print, obviously with the longest dimention 30". I actually hope to get a few of these on one sheet as well as some other images possibly if I am going to go print on that size sheet anyways. When shrinking down my image to 30" what settings should I use? Should I also increase the dpi to 300?

[Medley]

OK, let's start with the basics. What are the pixel dimensions of the image you want to print? Everything else you do will depend on that.

- Joe U.

[tayl0124]

66.071x9.108 at 240dpi or 15857x2186. The final submitted image will be a 20x30 inch size though, with more than one image placed on that print.

[OldClicker]

66.071x9.108 at 240dpi or 15857x2186. The final submitted image will be a 20x30 inch size though, with more than one image placed on that print.

At 300 DPI:

You want the long side 300 Dots Per Inch (DPI) x 30 inches= 9000 pixels.

To maintain the aspect ratio of 15857x2186:

9000 / 15857 x 2186= 1241 pixels At 300 DPI= 4.1 inches.

4 of these will be 16.4 inches high which leaves 0.72 in top, bottom and between each one.

TF

[Medley]

OK, so 15857x2186. Forget the dpi thing for now, because the printer won't use it anyway. SO, If you're printing on an Epson printer ( and ONLY if you're on an Epson):

Go to Image> Image size, and set the length to 10800 pixels. That will make the height 1489 pixels. The print will be 30" by 4.13 inches, and you can get 4 prints on a 20x30 sheet.

If you're on any printer OTHER than an Epson:

set the length of the image at 9000 pixels. This will make the height 1241 pixels, with the same 30x4.13" print size. SO you can get the same 4 prints out of a 20x30 sheet.

The reasoning behind these figures is somewhat long, but here's the short version. Your printer has a "native" resolution. It prints images at a certain resolution, regardless of the resolution set in PS. If an image is too large or small to accommodate the native resolution, the printer simply resizes the image.

The telltale sign that a printer has resized the image is that the sharpening halos have been either enlarged or reduced. At native resolution, the printer simply passes the halo size through to the print without changes.

As it turns out, the native resolution of MOST printers is at or about 300 dpi. Epson is the oddball, with a native resolution closer to 360 dpi.

The 240 dpi setting you often see is a result of Epson's native resolution. If you can't print an image at the printer's full native resolution, then you can (generally speaking) get a better quality print by using some harmonic of the native resolution. On a printer with a 300 dpi native resolution, that would mean that 150 dpi is good, 200dpi is better, and 300 dpi is best. On an Epson however, those numbers are 180, 240, and 360 respectively.

Most of this is technical stuff that you will likely never need. All you really need to know is that to get the maximum quality print, multiply the print size by 300 to get the pixel dimensions to send to the printer- unless the printer is an Epson, then mutiply by 360. DONT rely on the resolution setting in Photoshop. Resize for print.

- Joe U.

[tayl0124]

okay, so I know that they place that I will be printing from uses an epson printer. So what you are saying is leave it at 240 in ps, but make sure that it is 10800 pixels long??

[Medley]

I'm saying make it 10800 pixels long to get maximum resolution, regardless of what res PS has.

- Joe U.

[Norfindel]

Resolution only has a meaning when a physical medium is involved. In a picture from a digital camera, is just some random number thrown there by the manufacturer.

I think you could just go to "Image Size", set 360 or 300 dpi as resolution, and 30 inches as print size (with resample checked). Photoshop will do the math, and use 10800 or 9000 pixels width. But it's always a good idea to know what's happening there and why is Photoshop using that number of pixels. 360 dpi * 30 inches = 10800 pixels.