Stemming from a discussion elsewhere about printing and what PPI to send to the printer with one person claiming you really do not need to send more than 100 PPI to the printer (any printer) to get a decent result and me saying that ideally you should be sending at your printers native PPI either Epson or Canon and upping the file resolution if necessary rather than allowing the print driver to do this. Basically what Jeff Schewe has been recommending, at least as far as I recall.
This has been my habit for quite some time now and using an aging HP B9180 (or entry level Canon A4 for the odd 6x4 holiday snap) have been generally quite satisfied always sending either 300 PPI or 600 PPI and either upsampling in PS or more recently LR, and consequently not recently done any comparison with just allowing the printer driver to get on with it vs sending upsampled data - until recently.
I originally posted
Here but in an effort to be brief did not explain clearly and as it was a bit of a hijack decided to go into more detail and show an example or two.
Basically I was surprised by the improvement obtained printing a small crop at native resolution vs upsampling to printer PPI. TBH, I did not expect to see such a large IQ improvement and has caused me to question, my method, the printer etc. and ask here if what I am seeing is to be expected.
I thought that it would be best to show a couple of images to enable you to see where I am coming from:
The original image a 7 shot hand held pano. I am trying to decide if I like it enough to actually print large after cropping some more of the foreground. I have been trying to get a better shot with more foreground interest but so far after several visits no luck
An individual frame with ROI highlighted
Outputting from LR I made two small prints of the cropped area measuring 7.45"x 4.40". One at the crop native resolution as shown by LR of 107 PPI and the next by selecting the print resolution 300 PPI manually, both on the same entry level A4 Canon printer. For both prints set LR sharpening to low and glossy paper (actually used Canon Semi gloss) and just allowed the printer to colour manage. To enable comparison to be seen here did a quick scan of both images (all scanner sharpening and effects turned off) and combined in PS and Save for Web. I know the colour is way off but the difference in resolving detail between the two is what I am really interested in and the comparison seen here is pretty much what I see in the print when viewed closer than about 2 '. Viewing any farther away than this then the difference as expected soon vanish
.
So after all that my questions are:
Considering the crop native resolution of 107 PPI would you expect to see such a difference after upsampling to printers native 300 PPI?
As LR has limited user control of output sharpening am I correct in assuming that there would be a change in both radius and amount between 107 and 300 PPI?
If that is the case does it fully account for the difference?
Or
Have I just somehow fouled up somewhere and the difference you would expect to see is smaller than my examples ?
I know that this is somewhat lazy and I should revisit this to confirm but I would appreciate your comments