Canon digitals, why the size?

Discussion in 'Photography / Video' started by GAT, Jan 13, 2013.

  1. GAT

    GAT Dumbfounded

    Joined:
    Nov 16, 2012
    Messages:
    4,787
    Likes Received:
    3,095
    Location:
    Willamette Valley, OR
    I've own many different digital cameras but prefer Canon for my DSLR. All of the Canon products produce huge size images at a low rez. Sure, you can mess around with a photo editing program to change the photo to a normal size and dpi but none my other brands of digital cameras produce large size photos at a low dpi. Do you guys know why Canon takes this approach? For the life of me, I can't see the advantage.
     
  2. Josh

    Josh dead in the water

    Joined:
    Mar 26, 2006
    Messages:
    3,081
    Media:
    11
    Likes Received:
    583
    Location:
    NW Washington
    DPI only has to do with printing output. It doesn't have anything to do with the quality or "resolution" of an image file. 3000 x 2000 pixels at 72 dpi (or ppi if you call it that) has the exact same amount of digital information as an image that is 3000 x 2000 at 500 dpi. The only difference is the size you have the file set to print at.
     
  3. GAT

    GAT Dumbfounded

    Joined:
    Nov 16, 2012
    Messages:
    4,787
    Likes Received:
    3,095
    Location:
    Willamette Valley, OR
    I figured as much but the other brands don't use the approach. I know about dpi and all that, it's just odd that Canon uses the system that it does. Unless you have a photo editing program to change the size, it seems like you'd have a tough time printing such large photos. I fail to see any advantage in the system.
     
  4. Dan Nelson

    Dan Nelson Hiker, Fisher, Writer, Bum

    Joined:
    Oct 20, 2007
    Messages:
    845
    Media:
    1
    Likes Received:
    366
    Location:
    Puyallup, WA
    Home Page:
    As Josh says, you can set the image size your camera captures -- print resolution is meaningless in the camera settings. Don't like huge files, reduce the resolution setting (and really, in this day of dirt cheap digital storage capabilities -- 1 TB harddrives for $60! -- do you really see huge files?) I shoot Canon, Pentax, Nikon and Panasonic digitals (dSLRs as well as compacts) and have not run into the issue you describe. Of course, I shoot everything in RAW when possible, so file size is a big as possible for me.
     
  5. tkww

    tkww Member

    Joined:
    Nov 11, 2006
    Messages:
    502
    Media:
    3
    Likes Received:
    77
    Location:
    WA
    I think what Gene is talking about not the overall resolution of the file (6, 10,12,16 MP, etc.), but rather the settings in the file talking about how those are arranged. What we would properly refer to as PPI. That is an arbitrary setting put in there by the firmware of the camera. Clearly canon codes their firmware to put 72 into that slot. 72 (along with 96) are throwbacks to very old days in computing. Why they still hang around, who knows.

    I never make prints directly from a camera's file, but I suspect it would be easy enough for a photo printing machine to simply ignore the PPI setting and use the resolution that is there. If you choose "4x6" it's not going to spit out an 11x17 just because that's what the exif data says.
     
  6. GAT

    GAT Dumbfounded

    Joined:
    Nov 16, 2012
    Messages:
    4,787
    Likes Received:
    3,095
    Location:
    Willamette Valley, OR
    tkww, thank you! No one else could figure out what the hell I was saying. I may have born at night but not last night. I do know a little about digital cameras.

    I just took a photo using the max resolution setting in my Canon 60D. Why on earth would I want to reduce the resolution of the camera when all the other brands I own are also set at max resolution? The size of the image from the Canon is 72 inches by 48 inches at 72 pixels.

    All my Canon digitals create the same size image. The question is, why the hell is Canon using 72 pixels and an absurd size instead of 300 pixels at a usable size as do the other brands?

    It still doesn't make sense but I guess Canon is stuck in the past and isn't inclined to climb into the current century. I thought they may have had a good reason for using 72 pixels and a large size image but evidently not.
     
  7. tkww

    tkww Member

    Joined:
    Nov 11, 2006
    Messages:
    502
    Media:
    3
    Likes Received:
    77
    Location:
    WA
    Well...300 is just as arbitrary, though closer to what would often be useful.

    From a printing--offset press--perspective, PPI is supposed to be 1.5-2x the line screen (essential DPI) that the press is set to. So if you were going to print with a 133 line screen, you'd run photos with ~200-250 ppi. Factors for how much resolution you'd use include the quality of the printing, the material being printed on (coated, uncoated, newsprint), etc. There are debates as to how low you can go with the PPI and how much the difference matters going up. But the point is, you'd never use more because it is impossible for the press to utilize the information. IOW, after a certain point, the only thing you get is larger file sizes instead of more detailed pictures.

    But now we also have a host of other print making machines. Most notably from a photo perspective would by dye sublimation and inkjet printers. You can see all kinds of debates, things like using a PPI that is a multiple of the printer's DPI, that Brand X likes 266 PPI and Brand Y likes 288. It goes on and on.

    But to the point, throwing more pixels per inch at an image doesn't necessarily guarantee a more detailed image, particularly after a certain point. Though not giving it enough PPI will lead to a quality loss. 72 isn't going to cut it on any device, not even the world's worse newsprint printing job.

    Well, camera companies are often remarkably out of touch with how their products are used. This wouldn't be the first example of that! But out of curiosity, Gene, when is the 72 PPI setting giving you fits?

    ~Tyson
     
  8. GAT

    GAT Dumbfounded

    Joined:
    Nov 16, 2012
    Messages:
    4,787
    Likes Received:
    3,095
    Location:
    Willamette Valley, OR
    It really isn't that big of a deal but the other camera companies don't record large dimension size files with a low PPI. When I open an image in PhotoShop taken with a Canon , I am required to change the PPI and dimensions (unless I want to buy large photo paper to print the photo at 72 PPI) . Again, I was just curious if there is an advantage as to how Canon cameras record digital images and so far, no one has given any indication there is any advantage whatsoever. I fully understand all I need to do is change the size and PPI in PhotoShop but because other camera companies do not record digital images in the same manner, I thought maybe Canon was onto a better system -- I am now confident that they are not.

    There is no advantage in the manner in which they record digital photos. All it does is create a few extra steps I need to make in PhotoShop.
     

Share This Page