A visual center

[davidh]

Jonathan and Kiril,

Would it make sense, and is it feasible, to add the attached "Visual center" as another option to the Vertical dropdown list of the Print dialog?
There are certainly various visual centers for diferent purposes, but this one is considered to be the standard or one of the standards in some galleries and exhibitions.
Since the position of the lower right corner of the image is dependent on the image dimensions, placing the image to this visual center on the print would be much easier, if it could be automaticaly calculated instead of having to draw it first on a separate sheet of paper, measure the distance from the bottom and enter it into the Bottom Margin.
The fact is that the image printed in this visual center looks better even if it is not intended for a gallery.


And one more suggestion. The green and particolarmente the yellow curves in the Printer curves dialog are not visible much clearly on the gray backgrounh especially when they are close toghether. It might help to make all the curves thicker or the background color white. What do other think about it?

David

[Charles2]

I don't know whether it is a good idea, but if it is, it might be better to put the choice in the Layout transformation on its dropdown menu for Alignment of a panel.

One reason I don't know about the idea itself, which is new to me, is that brief search on the Web shows that visual center is defined with some flexibility, similar to the choice of Rule of Thirds or Golden Ratio intersection points for locating the subject of an image.

[den]

One could possibly modify the "PWCompositionGuidelines.txt" file located in the "<username>/AppData/Roaming/Digital Light and Color/Picture Window" folder with the added text section...

begin_object
name "Visual Center"
line 0.0 0.5556 1.0 0.7778
horizontal 0.7778
vertical 0.8
end_object

Then use the resulting grid lines in Preview of a Composite-Blend 1-point alignment shift transformation where the Input is the background image and the Overlay the 'image' to be positioned.

The above suggested text section is based upon the very small scale of the OP image and would generate grid lines as illustrated below when Window/Grid 'Visual Center' is selected...

capture_31072015_203311.jpg (54.91 KiB) Viewed 14452 times

If there is a specific mathmatical reference, the suggested text section could be refined accordingly.

...den...

[Dieter Mayr]

Charles, Den,

As far as I understood David's concept (wich took me a while to come to a understanding) i would think its a good idea to put it into "Guide Lines" (of which I thought first too).
My understanding of it:
You have a sheet of paper (the darker grey lines) and a image (the blue lines).
First you place the image in the top left corner of the paper and divide the remaining spaces of the paper in half for the light grey vertical and horizontal like.
So if x may be the papers horizontal dimension and y it's vertical dimension, p the images horizontal dimension and q it's vertical dimension, the horizontal coordinate of the vertical lines would be p+((x-p)/2), the vertical coordinate for the horizontal line q+((y-q)/2).
The angled line goes from 0 ; q to x ; q+((y-q)/2) then.
All coordinates with respect to the upper left corner.
After moving the images lower right point to the red circled point this results in a image centered in the horizontal, and lifted slightly in the vertical by that small amount the litte triangle at the red circle.
And that amount depends on either the paper size, image size and image aspect ratio, so it can't be adressed with a single block in Guide Lines.
The Print processor would on the other hand know everything to calculate that coordinates.
The effect is the same as, when matting a print, the bottom margin of the mat is usually cut wider then the top margin.
So, if it's decided to include this, I think ot would be useful to include it in both directions, horizontally and vertically, to be able to lift a landscape oriented picture printed on paper oriented portrait in the printer.
The settings would be "Centered" in one dimension and "Visial Center" in the other, so all possible orientations could be accomplished.

(and sorry for the math-heavy post, but i thinks its the easiest way to describe what's going on)

[den]

Thanks Dieter...

I think if I were to do this on a routine basis, I would try creating an Excel program where the inputs are paper size and image size [...aspect ratios determined from size entries...] and the output would be used for either Crop/Add Border borders or the margins of the Print transform...

...until perhaps PWP program changes are made...

...den...

[Dieter Mayr]

Den, a Excel sheet is a good idea, just nailed together a rough example, if anyone wishes to improve it feel free to do so, please.
Tested only in mm, but should work in inches too if one uses the same units for every field.

VisualCenter.zip

(3.86 KiB) Downloaded 601 times

[den]

Dieter... ...Others:

1) agree, a Composition Guide(s) approach is not the solution here...
2) was able to verify the requested repositioning of the OP image on its background vertically with your suggested Excel sheet calculations with the addition of horizontal centering with a Left and Right border = (Page Width-Image Width)/2...
3) found that it was easier to understand and verify when dimensions where in pixels @ 100 dpi...

Test:
Portrait in pixels @ 100 dpi
Paper Width 193
Paper Height 285
Image Width 115
Image Height 160

Border Left 39
Border Right 39
Border Top 50
Border Bottom 75

VisualCenter-image_relocated-1.jpg (28.77 KiB) Viewed 14358 times

...den...

[Dieter Mayr]

Den,

I have just nailed together the excel sheet last evening while waiting for the charcoal for the grill to get ready, so I kept it as simple as possible and did not add the left and right margins as it is easily centered either in Print dialog or Layout.
The way I use it in Print dialog (assuming Portrait oriented picture on portrait oriented paper):

VisualCenter_Print.png (14.02 KiB) Viewed 14328 times

[den]

I like to know the border values... ...look what happens with the Mat & Frame transform when the vertical offset is used for the Outer tab dimensions, for example...

IMG_0991-HDR(3)-1.jpg (92.54 KiB) Viewed 14288 times

This was interesting...
Thanks for the OP... ...learning... ...discussions
...den...

[Robert Schleif]

Another place this capability could go is the matting and framing transformation where you could enter the paper size as the frame opening size and use mats of zero thickness and pure white in color. I'd love (see an earlier discussion on enhancing the mat and frame transformation) to see the capabilities of the transformation increased. Because of the limited utility of the mat and frame transformation in its present state, currently I place images on the print paper by creating a new image with size equal to the paper and use the composite tool to visually place the image where it looks good. Sometimes I miss though.