Let's Discuss Sharpening... - DPChallenge Forums

Canon EF-S 17-55mm f/2.8 IS USM

01/26/2007 06:01:21 PM · #55

Originally posted by idnic:

Hmmmmm... Interesting. I assume you have a set of Smart Sharpen parameters you use for most images. What are those? I realize they will vary from camera to camera and probably lens to lens but I'm just curious.

What happens to sharpness when you upscale for printing?

Message edited by author 2007-01-26 18:02:42.

idnic

Canon EOS-60D

01/26/2007 06:07:20 PM · #56

Originally posted by stdavidson:

Right now my smart sharpen settings are 184, 1.0 and I rarely change them much from that (and never change the 1.0). Upsizing may diminish sharpening a bit, same as downsizing, so I use Sharpen faded back if needed. I do keep in camera sharpening at +1, I really don't think that makes much of a difference, but it makes me feel better. :)

Artifacts

Canon EOS-5D Mark II

Canon EF-S 17-55mm f/2.8 IS USM

01/26/2007 06:22:35 PM · #57

Originally posted by idnic:

Right now my smart sharpen settings are 184, 1.0 and I rarely change them much from that (and never change the 1.0).

You use defaults for the shadow and highlight settings?

idnic

Canon EOS-60D

01/26/2007 06:25:35 PM · #58

Originally posted by stdavidson:

Originally posted by idnic:
Right now my smart sharpen settings are 184, 1.0 and I rarely change them much from that (and never change the 1.0).

You use defaults for the shadow and highlight settings?

Yep. No need to complicate something that works just fine. :)

soup

Canon EOS-30D

Canon EF 17-40mm f/4.0L USM

01/26/2007 06:40:47 PM · #59

do you use a sharpened file when resampling up for printing?

i usually don't save the sharpening i do to the full res images - because i never know what exactly i might output it to when i open it next. is it beneficial to up-sample a sharpened image?

Originally posted by stdavidson:

ElGordo

Canon EOS-400D Rebel XTi

Sigma 18-200mm f/3.5-6.3 DC OS for Canon

01/26/2007 06:50:22 PM · #60

Since the subject came up, here is a novel sharpening method that has very little tendency to leave a telltale halo:

In PS CS2

1. Layer>duplicate layer (produces a 'background Copy')
2. On the layers palette, select 'overlay'(the image will look gross)
3. Using the background COPY layer apply filters>other>highpass with a small radius .5 to 5 pixels depending on image size. The background copy layer will become mostly gray with dark lines at image edges.
4. Adjust the opacity to suit and flatten the image.

Neat, huh!

Gordon

RIM BlackBerry Curve

Canon EF 85mm f/1.8 USM

01/26/2007 07:01:30 PM · #61

I had the interesting experience this evening when walking outside. It was a bright, but overcast day. Plenty of bare, thin twigged trees around.

Looking at them with an 'image processing' eye, they looked 'oversharpened' in real life. The typical things we consider for over sharpening, very dark to immediate light transitions, were there, all over the place.

So I can see that it would be near impossible to sharpen images of those sorts of things without adding in what look like halos - the appearance of halos is already there, in bright light.

soup

Canon EOS-30D

Canon EF 17-40mm f/4.0L USM

01/26/2007 07:05:27 PM · #62

sort of why i said apparently oversharpened earlier on... ;}

and with an image like that - especially with a ton of detail - resizing to fit a 150K or 200K limit doesn't do the 'unsharpened' image any good either...

Originally posted by Gordon:

01/26/2007 07:33:12 PM · #63

Originally posted by Gordon:

That, I believe, is part of my problem here. The branches were side-lit, and very high-contrast. There are no halos, but they did hold very high edge definition, due to the resampling strategy I used. Letting them go soft did not at all improve the look of the photo.
I'll have to experiment further with this and similar shots to find a happy medium.

01/26/2007 07:48:58 PM · #64

So, here's a very quick redux:

What I did to this was simply to apply a selective, 20% opaque gaussian blur of 1.5px to the high-detail, high-contrast areas. Does this remove the sense of being oversharp?

fotomann_forever

01/26/2007 07:50:12 PM · #65

Originally posted by kirbic:

So, here's a very quick redux:

What I did to this was simply to apply a selective, 20% opaque gaussian blur of 1.5px to the high-detail, high-contrast areas. Does this remove the sense of being oversharp?

That is a LOT easier on my eyes.

DjFenzl

01/26/2007 08:07:06 PM · #66

(oops, should have read the thread closer, this was duplicate info)

Message edited by author 2007-01-27 01:22:20.

01/26/2007 08:49:00 PM · #67

Based on the positive effect of the slight blur on hi-contrast detail, here's a 3rd edit:

I redid this one from the full-size image, and did only selective sharpening after resizing, to recover contrast in the detail in the rock formation. After comparing the submission and this result, I tend to agree that the submission, while not *technically* oversharpened, certainly had begun to have that over-contrasty look characteristic of oversharpened images, and so in fact it *was* oversharp.
This has been a great exercise; thanks to all who gave feedback! If anyone wants to post images for further study and discussion, feel free!

edit: If anyone's interested in looking at the original size of my image, it's here. WARNING! 7MB Image!

Message edited by author 2007-01-26 21:00:30.

01/26/2007 09:29:25 PM · #68

I'm still reacting to the tonemapping, but the effect is only barely there. I think it's a nice shot.

01/26/2007 09:32:52 PM · #69

Originally posted by DrAchoo:

I'm still reacting to the tonemapping, but the effect is only barely there. I think it's a nice shot.

Doc,
Cn you elaborate on what you're attributing to the tonemapping?

01/26/2007 09:37:06 PM · #70

Originally posted by kirbic:

Originally posted by DrAchoo:
I'm still reacting to the tonemapping, but the effect is only barely there. I think it's a nice shot.

Doc,
Cn you elaborate on what you're attributing to the tonemapping?

It's hard to say Fritz. I think I look at the water and it looks noisy. Maybe it's most obvious to me in the area below the reddish rock at the bottom.

I will quickly admit I could be totally full of it. It is hard to explain, but I still think it doesn't look "right". I've found lots of tonemapped pictures have this quality to me and it makes my own experimenting with Photomatix hard because I generally don't like the results I come up with.

Can you post a resized orginial? I can see if what I "see" is still there.

Message edited by author 2007-01-26 21:38:27.

01/26/2007 09:40:54 PM · #71

Originally posted by DrAchoo:

Originally posted by kirbic:

Originally posted by DrAchoo:
I'm still reacting to the tonemapping, but the effect is only barely there. I think it's a nice shot.

Doc,
Cn you elaborate on what you're attributing to the tonemapping?

It's hard to say Fritz. I think I look at the water and it looks noisy. Maybe it's most obvious to me in the area below the reddish rock at the bottom.

I will quickly admit I could be totally full of it. It is hard to explain, but I still think it doesn't look "right". I've found lots of tonemapped pictures have this quality to me and it makes my own experimenting with Photomatix hard because I generally don't like the results I come up with.

Ahhh. Ripples, LOL. If you can stand the 7MB download, take a look at the original, linked above. It's the same tonemapped file, just not resized. I think there's ripple detail that's just coarse enough to be reproduced, but comes out "choppy." I don't really know if it would look better with this smoothed out... Damn, I hate these small image sizes, LOL.

01/26/2007 09:46:49 PM · #72

Ya, it does seem a bit noisy for a 5D at ISO 200, doesn't it? I bet that's tonemapping artifact.

01/26/2007 09:55:41 PM · #73

Originally posted by DrAchoo:

Ya, it does seem a bit noisy for a 5D at ISO 200, doesn't it? I bet that's tonemapping artifact.

You looking at the water at the bottom perchance? I thought it was noise at first too, but it's actuallly not... it's image detail just at or slightly beyond the limit of the sensor's ability to resolve. Look at the deep shadow areas... they're clean.

01/26/2007 09:56:47 PM · #74

Originally posted by kirbic:

Originally posted by DrAchoo:
Ya, it does seem a bit noisy for a 5D at ISO 200, doesn't it? I bet that's tonemapping artifact.

You looking at the water at the bottom perchance? I thought it was noise at first too, but it's actuallly not... it's image detail just at or slightly beyond the limit of the sensor's ability to resolve. Look at the deep shadow areas... they're clean.

well, look at the noise in the sky and then "see" the same noise in the stream. I think it covers the whole picture, but fades in and out based on the detail of what is being captured.