Pre Sharpening?

[gcha]

When using RAW Conversion software like Capture One, is it advisable to use any Sharpening at that stage? Also when converting, what other functions should one use or not use in the RAW conversion utility?
Thanks & Happy Holidays
Gary

[JML]

The answer mostly depends on the specific raw converter and at what capabilities it excels. We only get one shot at true highlight recovery so always do that in the converter. In my brief trial of C1, the base conversion was excellent with accurate colors and great detail, but I got better highlight recovery results in PWP. For that reason, I did not purchase C1.

Most sharpening algorithms are a form of USM which is an RGB operation and is not done in raw even if applied in a raw converter. Nikon claims a special sharpening algorithm in their raw converter to undo softening induced by the AA filter. It uses a method called sparse derivative prior (not USM). Some say they can't see any difference between that and a capable implementation of post-raw sharpening such as Advance Sharpen in PWP. In any case, if noise is an issue with the image, I never sharpen in the converter but do NR downstream since sharpening exacerbates noise and makes it harder to reduce. I think Bibble claims they implement NR in raw before demoasic spreads the problem around. I have never tried Bibble so can't answer that question.

Most say that white balance should be done in the raw converter, but I’m fairly sure that WB is done post-demoasic in Nikon’s raw converter and probably offers no real advantage other than the utility of the controls. In PWP’s raw converter, I only put WB reasonably close and then use Color Balance to finish the job.

Some post-demoasic operations may be done when the image is linear (pre-gamma curve) which may offer an advantage as a gamma curve produces considerable compression in the highlights which are never quite the same afterwards.

The only way to really resolve the issue is to try the functions of the converter and then try to accomplish the same objective post-raw and draw a conclusion — but only after trials on a number of images. Also, always convert to 16-bit tiff as output from the converter for optimal capability in post-raw adjustments.

[gcha]

Thanks JML for your response. I have observed that Pre Sharpening before import into PWP seems to create a bit of noise, especially when a second stage of USM is applied in PWP just before out put to print. I have read in some foums to 'not sharpen at all before Raw Conversion" instead, sharpen Lightly, one or more times before printing. Is this correct? Can you indeed sharpen more than once or twice without "Over sharpening"?? I am trying to Sharpen with the least number of Resolution loosing steps as I can... I use USM mostly, I am still trying to understand the "Advance Sharpen" work flow. I also am using PWP 3.5.
Thanks again,
Gary

[JML]

Gary:

The most elaborate sharpening scheme was proposed by Bruce Fraser and calls for three phases: Capture Sharpening to offset the blurring induced by the AA filter and other digital capture factors, creative sharpening to improve the image, and output sharpening to compensate for image resizing and ink spread when printing or outputting for the web. So we can certainly sharpen more than once although the details are somewhat involved.

There was a recent discussion on the issue at http://dl-c.com/board/viewtopic.php?f=4&t=151 although I didn’t read it in detail.

The seminal work on the subject is Image Sharpening 2nd Edition by Fraser and Schewe. Other than the book, this pdf will provide perspective on the subject:

http://www.pixelgenius.com/tips/schewe-sharpening.pdf .

The sharpening in PWP's Advance Sharpen is very high quality and has the advantage of an on-board edge mask. The pdf by Schewe provides backgroung on edge masks which allow for sharpening detail and not sharpening smooth areas which is where noise shows the most.

Jim

[den]

Regarding "Creative Sharpening"...

I have found that it is particularly useful and generally generic to limit sharpening to an image's mid-tones so that highlight and shadow noise if present do not get sharpened and become more apparant... and limiting "creative sharpening" to mid-tones and visual elements of interest still seems to be a generic benefit regardless of the sharpening method: USM, AdvancedSharpen, HiPass, BilateralSharpen... at least from what I have observed.

When I was using PWP3.5's USM, I generally used USM settings of: Amount = Preference; Radius = 1 or 2; and Threshold = 3 to 5 (landscape image content) or 6 to 10 (portraiture image content) with a mid-tone edge mask. As I still have an older computer with PWP3.5 installed, I could suggest a "mid-tone edge mask" workflow if of interest.

[doubtingtom]

Surely of interest assuming it is something you can generate with ease from past routines. Transition to 5.0 should be reasonable?

Regards,
Tom B
St George, UT

[Phile]

Yes, I would like to see the mask for this if it isn't too much trouble
thanks

[den]

I had forgotten that I had written this...
http://www.ncplus.net/~birchbay/tutoria ... /index.htm.

Let me know if this needs further clarification as it is a close translation into PWP, BFrasers' PhotoShop suggestions... should be good for PWP3.5, PWP4, and adaptable to PWP5.

PWP5's "Mask Tool - Texture" tool can be used to find edges in lieu of the Edge transform.

A more simplified mid-tone Mask Tool - Brightness Curve can be used as well rather than BFrasers'... for example:
either a Smooth or BrokenLine curve = [0,0], [10,0], [30,100], [70,100], [90,0], [100,0].

[doubtingtom]

Den,
Thank-you for the follow-up and especially some settings. It make take some time to implement and test.

Regards,
Tom B