Image Capture PPI and a couple other questions

[Ernst Dinkla]

The article I wrote indicates the printer rez ratio is relevant for glossy type papers. I didn't test watercolor or canvas since I don't really print on that stuff. The odds are that exceeding 360 and using Finest Detail won't benefit from 720 PPI output with Finest Detail on because the papers/canvas can't hold the detail.

In any event, you should be testing this stuff yourself on your images, your printer & paper combo. All I can do is tell you what I've found after doing that testing myself.

Like I mentioned more often: if the best print quality possible with media+ink is not improving with input above 360 or 300 PPI then there are good reasons not to upsample to 720 or 600 PPI. In case there is more data than 360 PPI available at print size a good downsampling algorithm is important too.

Good test targets to check maximum printer/media/ink resolutions are available on more sites.

The old LL thread on this subject was:
http://www.luminous-landscape.com/forum/index.php?topic=54798.0


--
Met vriendelijke groet, Ernst

Dinkla Grafische Techniek
Quad,piëzografie,giclée
www.pigment-print.com

[Bart_van_der_Wolf]

The article I wrote indicates the printer rez ratio is relevant for glossy type papers. I didn't test watercolor or canvas since I don't really print on that stuff. The odds are that exceeding 360 and using Finest Detail won't benefit from 720 PPI output with Finest Detail on because the papers/canvas can't hold the detail.

Hi Jeff,

I have tested it and, a bit to my own surprise, there can be a significant amount of additional resolution above 300 or 360 PPI even when printing on non-glossy paper. On my Canon printer I can resolve 600 PPI detail of medium and high contrast on e.g. Hahnemühle Matt FineArt PhotoRag Bright White paper, so I have to assume it's also possible to achieve 720 PPI on Epsons.

Having said that, and while it is there, the resolution is not as well defined as on glossy paper because of the surface structure of matt paper and potentially more ink diffusion. That diffusion will also render fine detail darker, which may also lead to differences due to the orientation of the detail. On my printer the lines parallel to the print head travel direction are thinner and show less diffusion, compared to lines in the paper feed direction which are darker and slightly 'thicker'.

So in the end, the additional resolution above 300/360 PPI can significantly increase the effective output resolution on some matt (maybe not on the coarsest canvas) paper as well.

Cheers,
Bart

[Bart_van_der_Wolf]

Good test targets to check maximum printer/media/ink resolutions are available on more sites.ment-print.com

Hi Ernst,

Yesterday, I just happen to have added a couple of helpful features to my improved Siemens star type of Resolution Test Target. To print, one assigns a profile to the target and prints it without additional sharpening. To exclude any influence of the paper profile, one can also assign the paper profile to the target and print it with the same profile, which effectively should result in no profiling taking place.

While the target is ultimately intended for testing camera resolution, it is obviously also important to know that it is printed at high resolution to begin with. As a result of some recent feedback I was confronted with the need to be able and quickly assess whether the print was indeed done at the highest quality.

Now, one cannot only determine the actual resolution (in cycles/mm) capabilities of the printer in virtually all orientations, it will also allow to quickly determine whether it achieves the maximum horizontal/vertical printing resolution (and it proves that also matt paper can resolve in excess of 300/360 PPI). What's more, it also allows to immediately see the effect that the highest resolution has on a reduced tonality accuracy (because fewer dots can be used to dither the intermediate tones) of that highest detail.

Cheers,
Bart

[Damir]

I am at a native camera capture resolution of 97 ppi when sizing my image to 12x18 inches.  LR is set to up rez to 360.  Is there enough data in the cropped capture to make a decent print?  I realize there are many variables and grey areas in this question.  Is 97 ppi enough to warrant a try? 
...  

Thanks!

Paul

Camera do not have resolution in ppi, they just make picture A x B pixels, later on software decide about ppi because this is connected with output device. If you have 300 or 360 ppi you can see how big will be your print at that resolution, if you have 72 or 96 ppi you can see how big monitor you need to see entire picture. Anyway picture is the same.

[One Frame at a Time]

Getting back to one of your original questions...

In the Lightroom Print module, I created printing pre-sets to print successive 3" strips of an image on a single sheet. In Print, dragging the image shown in the test strip window will allow you to select which section of the image you want to print in the test strip. That same strip will print in the 2nd test trip you make. I've attached to screen shots showing Test Strip 1 and 2. Of course, when you go on to your next image to print, the rest of the sheet is available for subsequent test strips.
–Hope this helps.

Terry,  Thanks for posting that!!  It helps but could you please elaborate on your technique?  I am not sure what you mean by "dragging the image"?  Is there a way to select what part of the image opens in the 3 inch sliver or can you only get one side or the other (by rotating 180 degrees?)

Thanks,

P