Sharpening for large print? - DPChallenge Forums

02/14/2006 02:16:44 PM · #1

I am preparing a file for printing at 28x42" on 100%rag watercolor paper. So far, no sharpening has been applied to the file, which does not have an abundance of fine detail, but does have some areas with which I am concerned about haloing. The image is necessarily being upsampled quite a bit (to approx 7,000x10,000 from approx. 3000x2000) for printing at 256dpi. Does anybody have experience with this, and do you think that sharpening is necessary, and if so any suggestions on parameters?
This is the image:

02/14/2006 02:20:59 PM · #2

I have limited experience at such large sizes, but I have upsized to 16x24 and the picture did require sharpening. If you have only limited areas where you worry about haloing, it should not be too hard to use the history brush to selectively remove the sharpening from these areas.

As you sharpen, also watch the noise levels in the large uniform areas of sky and shadow in that picture. It's a tradeoff and if you run into more noise problems the benefit from sharpening might not be worth it.

02/14/2006 02:35:20 PM · #3

Originally posted by jemison:

I do not have experience to that size, but do to 18 X 24.

I recommend you upscale the image to the full size before applying any USM or sharpening. If you can I'd further recommend converting the image to 16-bit from 8-bit before upscaling. That doubles the file size but reduces color banding and minute pixelation in the sky.

Also, be viewing the image at 100% when you finally do apply sharpening. Be advised that it will be absolutely HUGE on your monitor for an image that big.

The amount of sharpening applied depends on the size of the print. The bigger it is the more sharpening that will be needed and the harder it will be to tell if it is correct. Try a radius value around 5 at 100% to start. That is a guess based on your largest upscale pixel side.

After sharpening you will want to go over the image with a fine toothed comb looking not only for haloing but for artifacts of any kind. Clone/heal/blur/smudge out the defects. I would recommend print previewing the full sized image and looking for defects that way as well. What is invisible in a web graphic can be a huge defect in a large print. It takes a long time to do it and it is a lot of work but well worth the final result.

Viewing distance does come into play with a print that large but I think you will find if the focus looks fine close up it will look spectacular at the proper viewing distance. :)

Btw... Congratulations on your blue ribbon for that very fine image!

Message edited by author 2006-02-14 14:47:52.

jemison

Canon EOS-5D Mark III

02/14/2006 02:56:05 PM · #4

Thanks Doc and Steve...I have applied a fairly low dose of sharpening, and don't see the effects I was worried about. I think I'll go with it and hope for the best!

Oh, one more question...what is the convention for signing this sort of print? embedded in file (ex. Bill Jemison Â©2005), or otherwise?

02/14/2006 03:17:20 PM · #5

There is potentially something else that can adversely affect the quality of your print. This is especially true when on special papers like watercolor... Out-of-gamut colors!

You won't see it on your monitor, but they can royally screw up a print! The effect is printer, ink and paper dependent.

The printer will guess and substitute its own colors if the incoming image contains a color gamut greater than that of the printer/paper combination. You can bet you will not like what it does. The result can be odd colors and serious loss of detail in the out-of-gamut areas.

Ideally, the way to check for this is to have view->proof setup->custom brought up and select the printer/paper that will be used for the print. Then you turn on view->Gamut Warning. You might not have that so may not even be able to know it is a problem until the print comes back looking bad.

Out-of-gamut colors for the printer/paper you are using will be displayed as grey on the screen. If present you might want to turn on your histogram display and add a color balance adjustment layer specifically to reduce and/or elimintate the out-of-gamut areas. The histogram display will show you what is going on. The grey disappears when the out-of-gamut colors are eliminated.

Out-of-gamut colors were a big problem for me printing on Ultra Fine Art paper on an Epson printer. But I was able to correct for that and the prints were just fine.

Think I am out of horror stories for now. :)

Message edited by author 2006-02-14 15:20:12.

02/14/2006 03:19:14 PM · #6

Originally posted by jemison:

I do not use an electronic signiture of any sort. I personally sign the print.

yanko

Carl Zeiss 50mm ZE f/1.4 Planar T for Canon

02/14/2006 03:26:29 PM · #7

I may be in the minority here but I thought this photo when it was submitted to the challenge at the time was oversharpened. I still gave it an 8 with the only negative being the sharpening. The parts that mostly bother me is the area of the bird. That's a sharpening halo right there or at least it looks like one. Perhaps it's natural, don't know. However it looks like a halo just not the more harsh looking ones. Anyway, just my two cent, carry on.

Message edited by author 2006-02-14 15:27:50.

02/14/2006 03:42:42 PM · #8

Originally posted by yanko:

Jemison can confirm, but I think that was a dodge you saw to bring the bird out, not a sharpening artifact.

Nikon AF-S NIKKOR 24-70mm f/2.8G ED

02/14/2006 03:45:21 PM · #9

Originally posted by yanko:

Haloing is one of the worst digital effects you can leave in an image. Even if not visible in the web graphic haloing can show up in a print.

In some prints, in order to achieve the degree of desired sharpening, I've had to generate some haloing. In those cases I review edges at high magnification and clone out haloing by hand. That leaves razor sharp, perfect edges.

Brent_Ward

Canon EOS-5D

Canon EF 85mm f/1.2L USM

02/14/2006 03:58:22 PM · #10

Originally posted by DrAchoo:

Originally posted by yanko:
I may be in the minority here but I thought this photo when it was submitted to the challenge at the time was oversharpened. I still gave it an 8 with the only negative being the sharpening. The parts that mostly bother me is the area of the bird. That's a sharpening halo right there or at least it looks like one. Perhaps it's natural, don't know. However it looks like a halo just not the more harsh looking ones. Anyway, just my two cent, carry on.

Jemison can confirm, but I think that was a dodge you saw to bring the bird out, not a sharpening artifact.

I would get rid of the bird. Only detracts from the balloons. Always has bothered me...

Neil

Fujifilm X-T30

02/14/2006 04:03:10 PM · #11

I havent done any of my prints in months, and so I've been doing them this past week. Up till now, I've been using SIPro2 to enlarge.

Since I had a lot I wanted to do, I decided to give Genuine Fractals a try. There's a trial version which gives you 20 uses for free, no restrictions.

All I can say is for such a large print, you should definitely use it. I have been amazed, so much so, that after my trial is over, I am going to plunk down the $200 to buy it.

Let me know how it works for you.

I have found that it's still a good idea to sharpen after you enlarge with it. Rather than use USM, I use FocusMagic. There's also a 5 use trial available of that, so for this print, you'd be set!

Stagolee

Kodak Easyshare C180

Canon EF 50mm f1.2L

02/14/2006 04:04:49 PM · #12

Originally posted by Brent_Ward:

Originally posted by DrAchoo:

Originally posted by yanko:
I may be in the minority here but I thought this photo when it was submitted to the challenge at the time was oversharpened. I still gave it an 8 with the only negative being the sharpening. The parts that mostly bother me is the area of the bird. That's a sharpening halo right there or at least it looks like one. Perhaps it's natural, don't know. However it looks like a halo just not the more harsh looking ones. Anyway, just my two cent, carry on.

Jemison can confirm, but I think that was a dodge you saw to bring the bird out, not a sharpening artifact.

I would get rid of the bird. Only detracts from the balloons. Always has bothered me...

My thoughts also, then how much sharpening would you need ?

jmsetzler

Sony Alpha a6000

Sony 16-50mm f/3.5-5.6 E-mount

02/14/2006 04:36:40 PM · #13

I wouldn't sharpen it much at all after you get it to size. I would use a USM setting of about 100 percent, 1.5 pixels, radius = 2. One thing I know for fact is that in most cases, when it looks sharp enough on your computer monitor, it's too sharp for print.

Sony 16-50mm f/3.5-5.6 E-mount

02/14/2006 04:52:31 PM · #14

Originally posted by jmsetzler:

One thing I know for fact is that in most cases, when it looks sharp enough on your computer monitor, it's too sharp for print.

That's interesting John, I had been under the exact opposite impression that a print properly sharpened will look oversharp on your monitor.

jmsetzler

Sony Alpha a6000

02/14/2006 04:54:02 PM · #15

Originally posted by DrAchoo:

Originally posted by jmsetzler:
One thing I know for fact is that in most cases, when it looks sharp enough on your computer monitor, it's too sharp for print.

That's interesting John, I had been under the exact opposite impression that a print properly sharpened will look oversharp on your monitor.

I have never had that problem. I believe that we, as digital photographers, generally oversharpen our stuff. I see it quite regularly in print around here (my area).

Stagolee

Kodak Easyshare C180

Canon EF 50mm f1.2L

02/14/2006 04:55:41 PM · #16

Originally posted by jmsetzler:

Originally posted by DrAchoo:

Originally posted by jmsetzler:
One thing I know for fact is that in most cases, when it looks sharp enough on your computer monitor, it's too sharp for print.

That's interesting John, I had been under the exact opposite impression that a print properly sharpened will look oversharp on your monitor.

I have never had that problem. I believe that we, as digital photographers, generally oversharpen our stuff. I see it quite regularly in print around here (my area).

I agree I do very little sharpening on prints.

Brent_Ward

Canon EOS-5D

Canon EF 85mm f/1.2L USM

02/14/2006 05:11:54 PM · #17

I've found that sharpening with a radius of 7 @ 500% is about right for critical print work...

front_element

Nikon D700

Nikon AF-S NIKKOR 24-70mm f/2.8G ED

02/14/2006 05:13:35 PM · #18

The print will definitely benefit from sharpening. If you can afford it buy this software:

//www.pixelgenius.com/sharpener/

This is pretty much universally acknowledged as the best image sharpening workflow available. I use for all my capture and output sharpening and the results are outstanding.

yanko

Carl Zeiss 50mm ZE f/1.4 Planar T for Canon

02/14/2006 05:18:10 PM · #19

Originally posted by DrAchoo:

You're probably right. I wasn't sure of what caused it. I assumed sharpening. Whatever it is it doesn't look natural to me. Removing the bird as Brent suggested probably would help.

Message edited by author 2006-02-14 17:19:35.

Brent_Ward

Canon EOS-5D

Canon EF 85mm f/1.2L USM

02/14/2006 05:21:23 PM · #20

Originally posted by front_element:

It's been endorsed by Luminous Landscape, it's must be good...

PhantomEWO

Canon EF 70-200mm f/2.8L IS USM

02/14/2006 05:57:55 PM · #21

Originally posted by Brent_Ward:

I've found that sharpening with a radius of 7 @ 500% is about right for critical print work...

So does everyone use USM and set the levels and radius or if you have PS CS2 why not use Smart Sharp instead? I ususally set it at .3 and then anywhere from 100-300 depending on what it is. Someone correct me and I'll do it right from now on ...

justin_hewlett

Canon EOS-1000D Rebel XS

Canon EF-S 18-55mm f/3.5-5.6 IS

02/14/2006 05:57:56 PM · #22

Originally posted by jemison:

This is the image:

Hmmm...To me, the horizon line looks slightly tilted to the left. Am I the only one?

02/14/2006 06:00:57 PM · #23

Originally posted by Brent_Ward:

I've found that sharpening with a radius of 7 @ 500% is about right for critical print work...

It's funny how different people use USM different ways. This is soooo far above what I use I wondered if it was a joke Brent. The radius will, of course, go up the larger the picture, but even on my 16x24, I can pretty safely say I probably didn't go higher than 2.5/150% (and possibly lower).

For our little 640px entries, I rarely go above 0.9/100% and often am down at 0.7/50%

PhantomEWO