Digital Light & Color

This effect tends to increase detail by forcing edge darkening at sharpen edges and/or tends to provide a darkened halo ambience with no sharpening.... and was suggested by Dave Jaseck on the DPR Retouching forum: http://forums.dpreview.com/forums/read. ... e=34747488.

...This is a blast from the past as I rummaged through my old stuff. A technique described by a fine gentleman John Davies from the UK who has since passed on. Thought you might be interested in this simple effect which adds a subtle though pleasant effect. John called it Bled Black, I feel more comfortable calling it Black Bleed. Was a old wet darkroom technique. Easily made into an action (which I have done) and additional steps can be added to embellish the effect. Here are the basic steps:
Make a duplicate image
Layer>duplicate layer call it Black Bleed Effect
Image>adjustments>invert
Filter>other>maximum, set to 2 pixels
Filter>blur>gaussian, set to 5 pixels
Image>adjustments>invert
Set opacity of Bleed Black Effect layer to 50%
You can then try saturation or sharpen on the overall effect, or adjust various settings...
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Thanks, Dave. Can you get the same effect by not inverting and running minimum plus GB? [GB = Gaussian Blur] ....Ronny Harris

a PWP5 workflow....
Basic Steps:
(1) click on the 'starting image' and find edges with Mask Tool-Texture: move white slider left to right edge of histogram; Apply; Blur=2; Apply. Leave mask 'active'.
(2) click on the 'starting image' and open the Filter transform where Input=Filter='starting image', Additive, mask white=100; EC=0; and OK.
(3) Apply a GaussianBlur [Amount=100, Threshold=100, Radius=3 for a 800x533 pixel image or Radius=5 for a 3456x2304 pixel image] to the 'resulting Step2 image'.
(4) click on the 'starting image' and open Composite-Blend, setting Overlay='resulting Step3 image'; Input Mask white=100; Input Mask black=38; Overlay Amount=50; and OK.

Added sharpening (optional):
(5) Apply a USM sharpening [Amount=50->100; Radius=2; Threshold=3] to the 'resulting Step4 image'.

Effect is most noticeable at the posting resolution by the additional fullness of the rightside, foreground, silhouetted upper tree limbs and the decrease in light halo at the middle distance treeline.

Den, can you briefly describe what each step is accomplishing and why it's included in the recipe? Cheers.

In interpreting the suggested PS workflow, I assumed changes performed in the RGB color space and that the two "Invert's" were unnessary as suggested by the followup posting by RHarris if one changes the filter mode...
...and further that:
(1) "Filter>other>maximum" is PWP's Filter transform in Subtractive mode, Amount=100, EC=1.0;
(2) "running minimum" is PWP's Filter transform in Additive mode, Amount=100, EC=1.0; and
(3) knowing that PWP's Filter transforms in the RGB color space and when filtering an image with itself in Additive mode: darkens, and increases contrasts and saturations; and in Subtractive mode: lightens, and decreases contrasts and saturations...

I further took the liberty in the OP to restrict the effect to blurred edges [Basic Step (1) of the OP] and more restricted blending [Basic Step (4) of the OP]...

...but perhaps a closer PWP interpetation of the PS workflow is:

Basic Steps:
(1) click on the 'starting image' and open the Mask Tool-BrightnessCurve and Appy-Add the default diagonal line curve; set Blur=2; Apply; and leave mask 'active';
(2) click on the 'starting image' and open the Filter transform where Input=Filter='starting image', Additive, mask white=100; mask black=0; EC=1.0; and OK;
(3) Apply a GaussianBlur [Amount=100, Threshold=100, Radius=5 to the 'resulting Step2 image'.
(4) click on the 'starting image' and open Composite-Blend, setting Overlay='resulting Step3 image'; Input Mask white=100; Input Mask black=100; Overlay Amount=50; and OK, creating the Black Bleed effect image.

where:...
...Basic Steps(1) and (2) Filters an image with itself at a radius of 2 pixels in Additive mode: darkening, and increasing contrasts and saturations limited by the white/gray blurred HSV-V luminosity mask.

...The 'resulting (1)-(2) image' is further softened with a 'gaussian blur' whose radius is 5 in Step (3),

...The 'starting image' is then 50% blended with the 'resulting (3) image' in Step (4).

...at this point, DaveJaseck suggests: "You can then try saturation or sharpen on the overall effect, or adjust various settings"...

An additional observation... lower midtones and shadows have a tendency to get overly dark particularly for an under-exposed image, so perhaps limiting this effect to a 40 to 100% tone range would be a preference or simply 'one to one cloning' preference image areas from the 'starting image' into the resulting Step (4) image.

It is mentioned that this effect bases on a old wet darkroom technique.
Searching for the two given name in the atricle did not give satisfying results.
Does anyone have a idea about how it is made in the wet darkroom?

Thanks in advance

A way to enhance edges in the wet darkroom was to use a very dilute developer and little agitation during development. The developer would be locally more or less depleted depending on how dark an area was. Thus it would produce stronger blacks adjacent to light areas. In extreme cases, the image almost had a look of being outlined in india ink.

Kiril

Pyro or staining developers claim to produce edge effects. Here is a reference: http://unblinkingeye.com/Articles/PCat/pcat.html

Kiril

Edge effect - that was the term i could not find in my memory.
Thanks Kiril, is always easier to look for something when knowing the word to look for.

How different the effects of this technique will be from applying the USM with with a sizable radius and then canceling the white part of the edge halo (by e.g. compositing the original image with its 'USM'd' version in darken mode)?

MaciejT...

There seems to be a 'diffusion' aspect to this technique as well... so perhaps a refinement to your suggestion would be to:

...compositing the original image with its [blurred] 'USM'd' version in darken mode...