[Leica] Random observations on resolution (long and irrelevant to the craft of being a good photographer)

[hlritter at bex.net (Howard Ritter)]

Yes, something isn't kosher. Your file should be about 6000 x 4000, for 24 
megapixels. I don't know anything about Lightroom (yet) but perhaps there is 
a setting that will import a file at lower resolution than native, but if 
you're going to manipulate an image I'd have to think that there's no reason 
to bring it in at anything other than native. In fact, the file you describe 
can't be just a down-sampled native file because the proportions are not 
3:2. Something is definitely amiss.

As I said in my post, upsampling to improve the appearance of small details 
is useful only when the final viewing size is so large that you're looking 
at it near the limits of resolution, which is not the case unless the whole 
file is printed at a scale where the native pixel count is down to maybe 
half the range of the pixel density at which prints look good?say, 300 
dpi?meaning the original file would have to be stretched to maybe 150 dpi. 
This means that the 6000 pixels of the long dimension of the image file 
would have to extend to 40 inches. For a print at the size you mention, you 
could actually DOWN-sample by a factor of 2 and not lose anything. But first 
I'd figure out why you're getting the wonky pixel dimensions.

?howard

On Mar 22, 2014, at 5:59 PM, Bob Adler <rgacpa at gmail.com> wrote:

> Hi Howard, 
> Trying to wrap my layman's brain around this.  
> When I bring an M240 file into CC from LR with no resolution change, it is 
> 2,682 x 3352 px at 360dpi. It is 7.45 x 9.311 inches in size. 
> So if I use bicubic smoother and upsize the number of pixels to 2x(2,682 x 
> 3,352) or 5,364 x 6,704 at 360dpi I should get the effects you are 
> predicting: sharper looking images with smoother gradients BUT is now a 
> 14.9 x 18.622 inch size. 
> What needs to be done then if I want my print size to be at the original 
> dimensions: 7.45 x 9.311 inches? Or a larger size than the now 14.9 x 
> 18.622 inches?
> Thanks,
> Bob