printing above 300dpi, where (and why)?

[Brian K]

With Epson printers you'll find increasingly finer detail at 360, 480, and 720 dpi depending on the paper. It is my understanding that the epson will automatically do an interpolation to 360 using it's own software but it's just not as good as doing it beforehand.

On Mac, Ben Vista Photozoom 5 is an excellent interpolation program and will most likely give you better results than PS or LR. The current incarnation of genuine fractals, they have changed the name I believe to perfect resize, also does an excellent job.

[welly]

The native resolution of Epson printers is 360 dpi whereas Canon and HP are using 300 dpi print heads. If the file has a resolution of less than 360 dpi (in case of Epson) or 300 dpi (in case of HP/Canon), then the printer driver/printer will upsample to 360 dpi or 300 dpi, and likely introduce artifacts. Thus, some sources suggest using either 300 dpi or 360 dpi as the ideal resolution for the files to be printed.

As the printing module in Lightroom is very sophisticated, I usually print out of Lightroom most of the time. Here you can set the software (Lightroom) to upsample to a fixed resolution (i.e. 360 dpi in case of my Epson printer). The upsampling algorithms in Lightroom are much more refined than those in standard print drivers, so you will see the difference here.

If the resolution of the image when printed in a certain size falls above 360 dpi (which is the case when you've scanned film with a high resolution or are using high resolution cameras such as the Nikon D800 or MF backs), Jeff Schewe (author and co-author of various books on Photoshop, image sharpening and color management, as well as printing guru) recommends upsampling to 720 dpi (or 600 dpi for Canon(HP) in Lightroom. In addition to that (and when using a pro level Epson printer), he recommends setting the Printer Settings > Output Resolution in Lightroom to "Super Photo - 2880 dpi", uncheck "Highspeed" and check "Finest Detail". In my experience, this really makes a difference when using Lightroom as your "print engine".

Jeff Schewe has written an interesting article with samples to prove his findings here:
http://www.digitalphotopro.com/techn...esolution.html

You may need to follow a different strategy when using RIPs such as ColorBytes ImagePrint or others, though.

Cheers,
Andreas

I need to compare images I've printed on my 3880 using the Epson driver vs. QTR. I always use 2880dpi and finest detail when I use the Epson driver and I must say, the detail I'm getting from my prints at 8x10 is quite astounding considering I've scanned the negatives with a V700 scanner and I know little about sharpening images (I just play with the sharpen tool in Lightroom until, to my eyes, it looks sharp). I'm guessing I'm doing something right anyway. With QTR, the maximum DPI it'll print out at is 1440 it seems, unless I've missed a switch/button/checkbox or something else?

Still, the prints I've got out of QTR have been wonderful anyway.

[John Rodriguez]

If there are differences I bet they're subtle. I used to not be able to tell the difference between a file uprezed in photoshop and one eprezzed by the Epson driver. I finally found a site that showed side by side examples. It was the kind of comparison where I literallly had to be shown where to look and what to look for. And these were of very high resolution scans of inkjet prints. I don't think this kind of difference will be noticeable under normal viewing conditions except under unusual circumstances. I generally now interpolate to 360ppi in photoshop or lightroom, but it's on general principle.

True. Most comparisons I've seen only start to be noticeable on major uprezzing, ie 3-4x. The largest I go is an 80% uprezz, and that's only for a large print. That takes a 200 PPI native file to 360 PPI.

The nice thing about using Lightroom is it seems to do a really good job with output sharpening, so there's no need for me to create different versions for each print size (it's actually using the Pixel Genius Photo Kit Sharpener routines). I just dial up the size I need to print and let er rip.

[Brian K]

A friend of mine who is a serious master of the digital printing process, the paper companies come to him to make profiles, has shown me test printings whose incredibly fine detail blows me away. He'll hand me a piece of paper with what looks like a series of continuous fine lines on it and then hand me a loupe. In reality it's incredibly small type, almost like the micro type on US currency, which is perfectly legible and well defined. Very impressive.

[sanking]

I need to compare images I've printed on my 3880 using the Epson driver vs. QTR. I always use 2880dpi and finest detail when I use the Epson driver and I must say, the detail I'm getting from my prints at 8x10 is quite astounding considering I've scanned the negatives with a V700 scanner and I know little about sharpening images (I just play with the sharpen tool in Lightroom until, to my eyes, it looks sharp). I'm guessing I'm doing something right anyway. With QTR, the maximum DPI it'll print out at is 1440 it seems, unless I've missed a switch/button/checkbox or something else?

Still, the prints I've got out of QTR have been wonderful anyway.

I believe you have indeed missed something in setting up QTR. All of the Epson printers I have used allow for setting up with 2880 dpi and uni-directional printing. In my tests this setting allows use of files with resolution of up to 720 dpi. Whether you will see any advantage compared to the Epson driver will depend on many factors, but one of them will be the actual detail in the image file. The best procedure is to never downsize the image to less than 720 dpi, and of course in order to see the detail of 720 dpi it must be there from the beginning, either from the digital capture or film scan.

Sandy