Sharpening & Printing

[aam1234]

Heard that you need less USM if you intend to print a photo. Is that true.

Thanks

[Scottes]

Generally more, really. As a rule of thumb, zoom the image to 25% and sharpen. When it looks good on screen it will look good on print.

This is just a rule of thumb, though.

[aam1234]

Thanks Scottes,

While my knowledge in post processing is close to zero (purposely), it didn't make sense to use less sharpening. What you said makes more sense.

Thank you

[Brian Tilley]

Generally more, really. As a rule of thumb, zoom the image to 25% and sharpen. When it looks good on screen it will look good on print.

This is just a rule of thumb, though.

Scottes,
Why 25%? Why not 100%?

[aam1234]

Generally more, really. As a rule of thumb, zoom the image to 25% and sharpen. When it looks good on screen it will look good on print.

This is just a rule of thumb, though.

Scottes,
Why 25%? Why not 100%?

I thought the same thing at first. I think what he meant was if you use 25% it will give you a rough idea how the print would look like (am I correct Scottes).

[chris.bailey]

Zooming to 100% is unrealistic in relation to the print size so will be hard to judge.

Note that an image that looks oversharpened on the screen will often be just right in print so it pays to experiment.

[aam1234]

Note that an image that looks oversharpened on the screen will often be just right in print so it pays to experiment.

So there is a relation between what you see in the screen and what's printed. Guess I got it in reverse.

Thanks for the clarification Scottes and Chris.

[chris.bailey]

Note that an image that looks oversharpened on the screen will often be just right in print so it pays to experiment.

So there is a relation between what you see in the screen and what's printed. Guess I got it in reverse.

Thanks for the clarification Scottes and Chris.

Sort of. You see it on screen at 72dpi but would print out at a much higher dpi. The edge contrast created by sharpening will therefore be more pronounced on screen than at print time.

Its also like putting salt on your fries, personal teste comes into it as well. I like prtraits with eyes that are sharp even if I have softened other elements so I will normally selectively sharpen the eyes more that the rest.

[aam1234]

Thanks Chris. Not only I learnt something new but you saved me few $$ too. Was planning to print two somewhat big photos, now I need to sharpen them a bit more before I do so.

Thanks again.

[Scottes]

If you view on screen you're viewing at 72-92 dpi. If you print you're probably printing at 240-300 dpi. So by viewing at 25% you'd be viewing a 300 dpi print at 75dpi. So the dpi of the on-screen picture now matches the print's dpi.

Well, close, anyway.

You'd think that viewing at 33% or 16.7% would make more sense because the numbers would come out closer to being accurate, but PS does some anti-aliasing at these odd-numbered resolutions and that anti-aliasing will cause an inaccurate look to the sharpening. So you should view at 12.5%, 25%, or 50%.


If you're going to print something large for the first time do yourself a huge favor and run some sample prints. I'd open the full-size image and crop out 4" x 6" of it - you can now use this to get some much, much cheaper 4x6 prints done with different sharpening and saturation.

Take that 4x6 crop of an important part of the image and then do Image... Duplicate a few times. Sharpen each one one of these duplicates differently and add some text to the print indicating the USM settings. I'd also increase saturation slightly on each one, and mark those settings on the print, too.

Now get those 3 or 4 4x6 prints made. Check them out to see which setting looks best. Now you'll have a good idea of what to use when you get the expensive full-szed image printed.

It kinda sucks when you give the printer some large prints and they all come out soft, or under-saturated. Those large prints can get expensive. Running some sample images is an inexpensive way to get a feel for your printer's processing of your images.

[CyberDyneSystems]

Just an aside..

In Photoshop.. allways view images in increments of "25"

ie: a 50% view will look MUCH more accurate than a 66% view...

I'm not sure what PS' problem is with the 33% and 66% views.. but the problem is there, very real and very visible.

Whereas at 50% and 25% you do get a very accurate rendition of the image scaled down.

[Scottes]

I'm not sure what PS' problem is with the 33% and 66% views..

...but PS does some anti-aliasing at these odd-numbered resolutions and that anti-aliasing will cause an inaccurate look to the sharpening. So you should view at 12.5%, 25%, or 50%.

[chris.bailey]

If you view on screen you're viewing at 72-92 dpi. If you print you're probably printing at 240-300 dpi. So by viewing at 25% you'd be viewing a 300 dpi print at 75dpi. So the dpi of the on-screen picture now matches the print's dpi.

Well, close, anyway.

You'd think that viewing at 33% or 16.7% would make more sense because the numbers would come out closer to being accurate, but PS does some anti-aliasing at these odd-numbered resolutions and that anti-aliasing will cause an inaccurate look to the sharpening. So you should view at 12.5%, 25%, or 50%.


If you're going to print something large for the first time do yourself a huge favor and run some sample prints. I'd open the full-size image and crop out 4" x 6" of it - you can now use this to get some much, much cheaper 4x6 prints done with different sharpening and saturation.

Take that 4x6 crop of an important part of the image and then do Image... Duplicate a few times. Sharpen each one one of these duplicates differently and add some text to the print indicating the USM settings. I'd also increase saturation slightly on each one, and mark those settings on the print, too.

Now get those 3 or 4 4x6 prints made. Check them out to see which setting looks best. Now you'll have a good idea of what to use when you get the expensive full-szed image printed.

It kinda sucks when you give the printer some large prints and they all come out soft, or under-saturated. Those large prints can get expensive. Running some sample images is an inexpensive way to get a feel for your printer's processing of your images.

Good advice there. I never knew about the multiples of 25 thing.

[dhbailey]

Just an aside..

In Photoshop.. allways view images in increments of "25"

ie: a 50% view will look MUCH more accurate than a 66% view...

I'm not sure what PS' problem is with the 33% and 66% views.. but the problem is there, very real and very visible.

Whereas at 50% and 25% you do get a very accurate rendition of the image scaled down.


I would think that 50% and 25% are powers of 2 (1/2, 1/4) without repeating decimal points that need to be rounded and so fit the computer's math processing much better than thirds do (33% or 66%) because of the fact that the processor has to chop off or round off the decimal points, and that can lead to improper relationships between things.

That's my guess as to why things at 25% or 50% act better.

[CyberDyneSystems]

I'm not sure what PS' problem is with the 33% and 66% views..

...but PS does some anti-aliasing at these odd-numbered resolutions and that anti-aliasing will cause an inaccurate look to the sharpening. So you should view at 12.5%, 25%, or 50%.

DOH!

Scottes.. you have to understand.. I'm speed reading! :oops: :oops: :lol: :lol:

[Scottes]

Scottes.. you have to understand.. I'm speed reading!

I know. That's why I typed it slower the second time.
:D

[gmitchel]

Generally more, really. As a rule of thumb, zoom the image to 25% and sharpen. When it looks good on screen it will look good on print.

This is just a rule of thumb, though.

The "Tip of the Week" on my site last week discusses using Print Size for judging sharpness on the monitor for an image intended for print.

http://www.thelightsrightstudio.com/DigitalDarkroom/TipOfTheWeek/2004NOV29/2004NOV29.htm

A couple of weeks earlier, I discussed why you need to dial back the zoom magnification during sharpening.

http://www.thelightsrightstudio.com/DigitalDarkroom/TipOfTheWeek/2004NOV01/2004NOV01.htm

Both include some sample images.

Cheers,

Mitch