# Photo Print Question



## Nathan (May 22, 2004)

Hey all,

I would like to get the photo at the link below printed onto canvas via canvaspop.com. I have had really good results with them in the past with a print of 16" x 24".

https://picasaweb.google.com/lh/photo/TOoJ71x3FlHQdXGON_g1OSJWa2t9AZ4_tavNDy8wDus?feat=directlink

My question is on the size of the image and how it will look once printed. The original dimensions are 4288 x 2848 from a Nikon D90. I was thinking of getting it printed 30" x 40" on canvas and then framing it to hang over the fireplace in my house. I am trying to see how it would look at 30" x 40" before I spend the money to get it printed. I know there is a way to crop a piece of the image and then blow it up to the dimension required but I am not sure how to do this. Does anyone know?

Thanks,

Nathan


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## Formula4Fish (Apr 24, 2007)

Nathan,

The aspect ratio of your original is 1.5:, same as 3:2. That means for every 2 inches (or pixels) of height, it's 3 inches (or pixels) wide.

The aspect ratio of 40x30 is 4 inches of width for each 3 inches of height.

For you to turn a 3:2 image into a 4:3 image, you will need to crop 490 pixels of width (290 off each side)... turning it into a 3797 x 2848 image.

If you try to print a 3797 pixel image on a 40" wide medium, you will be printing it at about 95 pixels per inch. It might look OK from a distance, but viewed up close I would expect to see a fair degree of pixelization.

To see what I'm talking about, all you need to do is crop your favorite JPG to 950 x 760 pixels, then print a 10" x 8" hardcopy of it.


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## Formula4Fish (Apr 24, 2007)

The "magic number" for the production of "photo quality" hardcopy, is 300 pixels (or dots) per inch. That's also where the retina can no longer see the pixels, at 10 inches. Using that benchmark, the biggest hardcopy a 4288 x 2848 image would produce would be 14.3 inches wide by 9.5 inches tall.


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## RustyBrown (May 29, 2004)

As F4F stated viewing distance becomes very important with larger prints. A print over a mantle for example could give up some ppi because it will be viewed from further away.

Here's an excellent resource http://bythom.com/printsizes.htm


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## Nathan (May 22, 2004)

I was able to simulate the quality of the image at two sizes. 

36x24 - the first one (will need to be printed at 8x10 to get the same DPI)

40x30 - the second one (will need to be printed at 8x10 to get the same DPI)

Original is the third one.

Let me know what you think..


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## Formula4Fish (Apr 24, 2007)

If you print either one of those images 10 inches wide, you will merely be producing two prints at 80 DPI. 

The top one, at 638 pixels tall will be 630/80=7.975 inches tall. 

The middle one, at 566 pixels tall will be 566/80=7.075 inches tall.

If you stretch either one of them to 8 inches, you distort the picture and drop the vertical density below 80 DPI 

Niether of them exactly "simulate the quality" of what you would get if you tried to produce a 36"x24" or a 40"x30" from the 4288 x 2848 original.

A 36"x24" from a 4288 x 2848 will print at 118 DPI. To simulate this, you need to print a 118 DPI image. It can be whatever size you wish, just so it's 118 DPI. If you want your simulation to be 8"x10", you need to print an image that is 1180 pixels wide and 944 pixels tall. If you want your simulation to be 5"x7" you need to print an image that is 826 pixels wide and 590 pixels wide.

Likewise, a 40"x30" will need to come from a 4288 x 2848 that has been cropped to 3797 x 2848, and it will print at 95 DPI. To simulate this, you need to print a 95 DPI image. If you want your simulation to be 8"x10", you need to print an image that is 950 pixels wide and 760 pixels tall.


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## Nathan (May 22, 2004)

F4F,

Thank you for your reply. Sorry it has taken me a while to write back. 

I actually did exactly what you indicated above on my original post. I guess I just wasn't clear in how I described it. 

What I did was calculate the vertical and horizontal pixels per inch. I needed to multiply the vertical dots per inch by 10 and the horizontal by 8 to calculate my simulated size.

I got the same size images you indicated and cropped the originals to:

1191 x 949 for the 36 x 24.

1072 x 759 for the 40 x 30.

I think I will go with the 36 x 24 and put it on a wide mat with a nice frame but I am still not sure. I don't know if I will be happy with the resolution of the 40x30 and since it doesn't share the same width to height ratio as the original, I dont like the idea of cropping the image.

Nathan


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