Printing VERY large

[Jackal]

I need to print out a black and white picture for some project for my 3d design class.

It's probably going to be around the full size image my rebel XT takes. It shows as 48 inches x 32 inches in photoshop.

I need to get it blown up at kinkos since that's pretty much the only place I can go to. The image is in black and white so it won't be expensive. The max height they can print there is 36 inches.

Do I need to change any settings like it's dpi?

All tips are greatly appreciated. Thanks!

[the7ferret]

Figure out what dpi they want at kinkos then go back home plug that DPI in photoshop and see what your size is. If its too small you can use photoshop to enlarge it but do it no more than 10% at a time to preserve quality.

[grandad35]

I note that you recommend increasing the pixel count by 10% at a time, while others recommend doing it in a single step. I did a comparison test (using PS7 and Bicubic interpolation) on a detailed image, and thought that the single step result had slightly better detail. What are the pros and cons of the two approaches? Would PSCS and its Bicubic sharpen make a difference in the results?

[ScottE]

Before you start using Bicubic interpolation in Photoshop check with your printer and find out whether they want you to do that. Most good print shops have RIP programs for their printers that do a better job than Bicubic. I forget what RIP stands for. It's something like Raster Interpolation Program.

If you have to do the interpolation yourself, I have found that the Pyramid interpolation method in Qimage generally does a better job than using multi step Bicubic in Photoshop. It is very slow though.

Scott

[Jackal]

Figure out what dpi they want at kinkos then go back home plug that DPI in photoshop and see what your size is. If its too small you can use photoshop to enlarge it but do it no more than 10% at a time to preserve quality.

Hmmm...

I just want the image to be 48x32 when it's printed. It shows it as 48x32 in photoshop. Will changing the DPI have any affect on the image size? When I do change the dpi I see the resolution sky rocket along with the file size. But the dimensions stay the same? Doesn't make sense to me.

Excuse my ignorance. I'm used to the darkroom :p

[robertwgross]

Jackal, I think there are some terminology problems here.

Resolution is the number of pixels x pixels in the original image. Later, if you have resampled it upward, then it might be pixels x pixels larger.

DPI is the number of dots per inch, and it is mostly a printer thing. For example, if you like it virtually perfect, then your standard, or the printer's standard, might be 300 dpi. Note that when you get into large prints, often you might need to relax your standards to 200 DPI or farther.

Total file size is that can get huge. That is resolution x DPI x DPI. (Yes, DPI squared)

If you can't get the total file size to fit onto one CDR, then relax to 200 DPI.

Your printer company might have limits and suggestions on making this work. Further, they may have a printer profile for you to use (in Adobe) to do color perfectly if it is a color image.

---Bob Gross---

[Steven M. Anthony]

Hmmm...

I just want the image to be 48x32 when it's printed. It shows it as 48x32 in photoshop. Will changing the DPI have any affect on the image size? When I do change the dpi I see the resolution sky rocket along with the file size. But the dimensions stay the same? Doesn't make sense to me.

Excuse my ignorance. I'm used to the darkroom :p

To get your image to print out at 48" X 32", you must be at close to 72ppi (pixels per inch). That's going to make a rather awful looking print.

[chris.bailey]

To get your image to print out at 48" X 32", you must be at close to 72ppi (pixels per inch). That's going to make a rather awful looking print.

Not really as you will view an image that size at a distance. I have blown 10D images up to 6' x 4' qute successfully and I will aim for 100ppi. In my experience it is better to accept a lower ppi than it is to interpolate upwards more than about 2 to 2.5 times the native resolution.

[tim]

I tried upsizing in 10% jumps and in one big jump, I preferred the look of one big jump.

[Hellashot]

To get your image to print out at 48" X 32", you must be at close to 72ppi (pixels per inch). That's going to make a rather awful looking print.

Probably not if you're standing 6 feet away from the print which is how far back you'll need to be to see the entire print. If you try and look at it as if it were a 4x6 yes it won't look good but then no one looks at a huge 3'x4' print with their eye 6 inches from it.

[tim]

I have two prints at 32*20 (or so), both were 100ppi before upsampling, taken with a 300D. You need to stand a couple of meters back from them to be able to see the whole picture easily, from that distance they look great. Any close than 1 meter you can see the lack of definition, though since it was done with a good printing system you can't see pixels.

[UncleDoug]

Probably not if you're standing 6 feet away from the print which is how far back you'll need to be to see the entire print. If you try and look at it as if it were a 4x6 yes it won't look good but then no one looks at a huge 3'x4' print with their eye 6 inches from it.

You are right on here.

The one-step resolution change will be fine for this situation.
We print images in this situation on a regular basis.
About a month ago we printed an image 50x50 @ 65dpi that came out stellar.
Realistically, when you are dealing with prints at this size, the only time you should be concerned with how it looks "under a loupe" is if you are printing from 4x5 or 8x10 tranny.
Ever been to Mountainlight? Galen Rowels gallery in Bishop?
Some of his prints are grainy as all heck up close. Step back a bit, to intended viewing distance, and his vision becomes crystal clear.

The other option is to print to canvas.
The tooth of the media "hides" resolution issues quite well. And it is a cool alternative, especially if you museum-wrap the image.

[Avalonthas]

I wouldnt recommend upsizing any image in photoshop using there basic algorithms. There are a few third party software you can buy for about 40 bucks that give u 5 times better quality upsizing then the original PSCs codes. There are photoshop plugins available to. I dont upsize so ive never downloaded one but i do remember seeing one around the forum somewhere

[UncleDoug]

I wouldnt recommend upsizing any image in photoshop using there basic algorithms. There are a few third party software you can buy for about 40 bucks that give u 5 times better quality upsizing then the original PSCs codes. There are photoshop plugins available to. I dont upsize so ive never downloaded one but i do remember seeing one around the forum somewhere

It realy depends on what level of quality you are going for, how many times(in the future) you will be printing large files that need to be upsampled and your budget.
I've used several of the upsampeling softwares. They tend to be selective as to how much "better" of a result you will get. But, still, you are upsampeling. Creating something from almost nothing (Information is gleaned from surrounding pixles).
These softwares tend to work best when upsampeling 10%-20% or less.

[tim]

I tried a couple of packages to upsize my pictures, to my eye PS CS worked just as well.

[tiching99]

on a slightly different note, what as the maximum size (in your opinion/experience) film-photo-quality print that one could obtain off a 8MP camera (like the 350D/Rebel XT)?

thnx

[tim]

Aim for 300dpi, the 20D's about 3500 pixels wide, so about 12 inches wide at top quality.

[Moments]

I would check with Kinkos as to what PPI they will print at. For most large format printers if I remember, the ppi would be between 150 and 175 ppi. If I were you I might make a few samples of small sections of your image once enlarged to your final size via either the 10% upsample, other software upsampleing, and also letting Kinkos upsample the image. For the final print, use the process that looked the best. (You will also see if the color, contrast etc is right. All output devices and locations are different.) Of course if it is in the budget to do so, or take the crapshoot and do what you think will look best without a test print.