6 megapixels blown up? - DPChallenge Forums

Lytro Illum Light Field Digital

10/04/2011 11:16:31 PM · #1

I was asked by a family member if she could make a print of my photo for her living room. She want to put it on a canvas and would like for it to be big. My only issue is that I only have a 6 megapixel camera (Nikon D40)...

Any size in which it may get funky/pixelated?

She is unsure of which photo she wants but for the most part I don't crop very much so I don't think that would be an issue. The one she picks I will make sure it is a printable dimension size.

Thanks. :)

yakatme

Nikon AF-S Nikkor 17-35mm f/2.8D IF-ED

10/04/2011 11:28:06 PM · #2

Quick answer, pretty big. There are others here who can probably give you better answers based on math and science. I can simply tell you that I've printed as large as 40 by 60" and it came out fairly good.

One way to look at it (before the scientists chime in) is to consider the viewing distance. Usually, the larger the picture the further the viewing point. If you take a close look at a billboard or an ad on the side of a city bus, you will see pixels but you don't normally view that large of a picture that close.

I think that you can probably feel comfortable printing at 20 by 30" or maybe even pushing it to 40 by 60" with some grain.

One thing to keep in mind...I know that Canvas on Demand, a company that many on here use and like a lot, print on canvas at only 150 dpi. That surprised me, but their prints do look good.

Lytro Illum Light Field Digital

10/04/2011 11:31:03 PM · #3

Originally posted by yakatme:

One thing to keep in mind...I know that Canvas on Demand, a company that many on here use and like a lot, print on canvas at only 150 dpi. That surprised me, but their prints do look good.

Pardon my stupidness but what is dpi?

yakatme

Nikon AF-S Nikkor 17-35mm f/2.8D IF-ED

10/04/2011 11:36:05 PM · #4

Dots per inch. Most people save their images for printing at 300 dpi. Canvas on Demand suggested to me that I upload at 150 dpi once when I had trouble uploading a very large file. They told me that they have always been printing on canvas at 150 dpi, including all of my previous orders, because the texture of canvas can't maintain 300 dpi anyway.

Techo

Canon EF 100mm f/2.8 USM Macro

10/04/2011 11:52:47 PM · #5

Originally posted by yakatme:

...
I think that you can probably feel comfortable printing at 20 by 30" ...

I agree. I printed out a 20x30 from an 8mp Canon 20D file and it looked really good, even up close. Make sure the shot is properly sharpened before sending off to print. Slightly more sharper than you're used to when uploading for the web. There's a lot to read online about sharpening for print.

Message edited by author 2011-10-04 23:55:27.

spiritualspatula

Panasonic LUMIX DMC-LX100

Nikon AF-S NIKKOR 24-70mm f/2.8G ED

10/05/2011 01:39:31 AM · #6

You can always find a groupon for canvasondemand and then upgrade it cheaply to a bigger size. You can get a 20X30 printed and delivered for $100 with the groupon.

Message edited by author 2011-10-05 01:39:57.

Art Roflmao

Canon EOS-6D Mark II

Canon EF 24-105mm f/4.0L IS

10/05/2011 02:15:56 AM · #7

I found a Groupon! Hurry, limited supply...

bobonacus

Canon EF-S 17-55mm f/2.8 IS USM

10/05/2011 09:08:31 AM · #8

You could also enlarge the image in photoshop to make sure you were happy with it before sending it.

Your camera has an image of 3008 pixels x 2000 pixels (3008 x 2000 = 6,016,000 pixels ie 6MP)

If you were to print at 150dpi then your canvass size would be 20 inches x 13 inches
ie 3008 pixels (or dots) at 150 dots per inch = 3008/150 = 20 inches wide and 2000/150 = 13 inches high (all rounded up to the nearest inch)
at 300 dpi which is really high quality printing it would print at 10 inches by 7 inches
at 100 dpi it would print at 30 inches by 20 inches

You could test the printing quality by cropping a section and printing on a 6*4 or something, eg crop a section of your image to 600 pixels by 400 pixels and print on 6*4 which will be 100dpi as I think that will still be very good.

As already mentioned you need to sharpen a little more for printing vs screen

Techo's 20*30 @ 8mp would be 117dpi

David Ey

Nikon D80

Nikon AF Micro-Nikkor 60mm f2.8D

10/05/2011 10:34:52 AM · #9

Want canvas help?

10/05/2011 11:28:44 AM · #10

Originally posted by David Ey:

Want canvas help?

I don't think I will need it. Here is why.... She wants to just take my image file to Wal-Mart and let them print it. She just wanted to know how big it could be before it got pixelated.

Lytro Illum Light Field Digital

10/05/2011 11:29:40 AM · #11

Originally posted by bobonacus:

Although I had to read this about 5 times to understand all the numbers, I do get it now. Thanks for the help!

yakatme

Nikon AF-S Nikkor 17-35mm f/2.8D IF-ED

10/05/2011 11:39:21 AM · #12

Originally posted by mbrutus2009:

Although I had to read this about 5 times to understand all the numbers, I do get it now. Thanks for the help!

I told you that the scientists would chime in.

Originally posted by mbrutus2009:

.... She wants to just take my image file to Wal-Mart and let them print it.

Noooooo! Never let anybody abuse your work like that!

Kelli

Canon EOS-D60

Canon EF 28-135mm f/3.5-5.6 IS USM

10/05/2011 11:41:59 AM · #13

Originally posted by mbrutus2009:

Originally posted by David Ey:
Want canvas help?

I don't think I will need it. Here is why.... She wants to just take my image file to Wal-Mart and let them print it. She just wanted to know how big it could be before it got pixelated.

Wal-Mart does canvas?

10/05/2011 11:46:10 AM · #14

I guess so. My sister-in-law (the one who wants it) told me that they do.

I don't know much about what is happening. All I know is she wants the file of the image that she chooses. She told me some prices last night so I assume that you can do it online or something.

bobonacus

Canon EF-S 17-55mm f/2.8 IS USM

10/05/2011 11:47:57 AM · #15

Originally posted by mbrutus2009:

Originally posted by bobonacus:

Although I had to read this about 5 times to understand all the numbers, I do get it now. Thanks for the help!

:) It took me ages to get my head around dpi

bobonacus