I remember when I first purchased my Canon 5D MKII. One of the drivers behind this decision was to have a 21MPixel sensor. This was partly due to the main stock library I supplied only accepting 50Mb files and the pixel count on the 5D making this easy to achieve without interpolation. The other factor was that I wanted to be able to print large; 30 inch, perhaps even 40 inch images with good quality. When I recently purchased my GX1 I was also keen to ensure it would allow me to print large.
The GX1 is a 16Mpixel camera but it’s only the 4×3 format that gives an image this size. The 3×2 (similar format to my 5D) gives a smaller size and the 16×9 a smaller image still. To put this into context the 4×3 image would produce a 45Mb TIFF image, which is just short of the size required by the stock library but it’s not too far off and easily achieved with some interpolation. Print size was however the more important to me and out the camera the image is around 15” on its longest side when printed at 300dpi.
Now you are possibly reading this and thinking that the resolution is more than enough to create a 30” print given the viewing distance should be at least 3 feet and I would agree with you. I am however quite fussy (as are most photographers) and I want to look more closely at areas of my photographs and feel happy and confident that the image stands close scrutiny. Now you might think I am ignoring lens quality (which is true) but I know the 14-45 standard lens I use is more than capable of resolving sharp detail. No, what matters to me is the question am I satisfied when I look at the image closely when I print at 30 or even 40 inches.
To test this I resized my starting image (above) to 30 and 40 inches at 300 dpi using Genuine Fractals. I then extracted A4 sized sections from each image, sharpened and printed these on A4 Gloss paper ready to examine the results. If you want to know why I picked this image it’s because it has lots of fine detail. The glass as you can see from the images below has lots of fine straight, parallel lines on it that will show up any problems.
Image sample when viewed at 100%.
So the results? I’m not happy with the 40 inch print when viewed closely but it will be fine at normal viewing distance. The 30 inch print as show by the sample below is however is very good and you need to look very closely indeed to see the problem areas.
Image sample from 30 inch print scanned at 75ppi.
I do however know that I could achieve a good 40 inch print as I would simply reduce the resolution of the 30 inch print to 200dpi rather than 300dpi. I am also questioning the results of the Genuine Fractals software as I find it produces quite blocky results and this is what I can see in the 40inch print, but that’s another issue for another day.
Have I proved anything? Only that I am now satisfied that the GX1 is a really credible performer and fast becoming my camera of choice.