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working with zones in B&W images


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I wonder if someone would be kind enough to help me, please? 

 

The work flow I would like to copy is best described in a video by Ian Barber, which shows what I used to do in Photoshop and, having bought Affinity Photo and cancelled Photoshop, I now need to do in AP. The video is rather long but the process is described starting at just before the three minute mark and is completed at around 10 minutes. I am confident that using AP the rest of the process described can be completed.  I am using Affinity Photo 1.5.3 on an iMac with the latest, up to date OS.  The video is:-

 

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It seems like what you are trying to accomplish is to drop a color measurement target onto the image at some critical location and measure its L value.  Then, with the L value measured, you want to make an adjustment (say, using Curves) to change that L value.  In the video to which you linked, the author does this by using the Color Sampler Tool in PS to read the L value of a particular area of the image - he then selects this area on a Curve adjustment using the Targeted Adjustment Tool in the Curves dialog to place a point on the curve corresponding to the L value of the selected area.  The author then manipulates the curve to change the L value of the area to the desired value, makes a mask to hide that adjustment layer and then selectively applies the adjustment using white paint on the layer mask to reveal the adjustment where he paints it in.

 

This is essentially dodging and burning, setting the "exposure" adjustment with the curve and then locally and selectively applying that adjustment through the mask.

 

You can do all of this in Affinity Photo.  You can use the tools in the Info panel to make and monitor the L measurements and adjustments.  You can use the Picker mode of the Curves adjustment layer to target specific areas in the image and drop a corresponding point onto the curve.  You can even work in Lab in a Curves adjustment layer without changing the document's color mode to Lab.

 

If you really need the Zone values tool, that does not exist in AP - just write down the L values that correspond to the Zones for the three color spaces that the video's author demonstrates - no need to use the panel at all, just look at your notes.

 

Here are some Affinity tutorials that might help:

 

Curves Picker:  https://vimeo.com/154293467

 

Multiple Color Formats: https://vimeo.com/149265352

 

Here is the tutorial page (200+ videos) to browse:

 

https://forum.affinity.serif.com/index.php?/topic/10119-official-affinity-photo-desktop-video-tutorials-200/

 

The Info panel is a little quirky at first - the three icons represent: top - what color mode you want the readout to display (RGB, Lab, etc.) - click on it to select the readout mode; middle - click this icon if you want the readout to display the color values under your cursor; bottom: click this icon to place a sampler and readout the color under the sampler.  BE AWARE! - the sampler will be placed at the top left corner of the document - you can then drag the sampler to the desired location on the image.  The top left corner is where every new sampler is created, unlike PS where the sampler gets placed on the location you click.  To create more samplers, or delete existing ones, use the small flyout menu in the upper right corner of the Info panel.

 

Like PS, there are two readouts you can configure independently.

 

 

kirk

figure.png

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> bottom: click this icon to place a sampler and readout the color under the sampler.

> BE AWARE! - the sampler will be placed at the top left corner of the document -

> you can then drag the sampler to the desired location on the image.  

> The top left corner is where every new sampler is created, unlike PS where the sampler gets placed on the location you click.

 

@kirkt  There's a small trick here you might be missing.  Instead of clicking on the colour sampler icon to have the sampler appear at the top left, the tool has another option.  Drag-and-drop the sampler onto the image.  You'll be given a small loupe tool which can aid your initial positioning (although I sometimes find it actually gets in the road and makes the task fiddly).  Release the mouse button when you have the sampler in position.  The sampler's position can then be fine-tuned in the normal way by dragging (or by going back and drag-and-dropping from the Info panel again if you find the loupe tool useful).

 

2017-09-21_21-18-09.png

—— Gary ——

Photo/Designer/Publisher: Affinity Store, v2.1.1 release

Mac mini (M1, 2020), 16GB/2TB, macOS Ventura 13.4.1(c) • MacBook Pro (Intel), macOS Ventura • Windows 10 via VMware Fusion • iOS: current release

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Having tried out the various ways of using the Info Palette I have a much better understanding than I had when I started. Do you know how many pixels the sampler reads?

 

The last stage of the process which I am trying to emulate, has not yet been achieved. In the video, when the picker is used from the Curves Adjustment layer, a column of figures appears alongside the column  generated by the sampler from the Info Palette. Thus, there are two identical columns of figures. When the curve is manipulated the L value from the picker changes following the movement, whilst that from the sampler is fixed. Without being able to read the L value from the curves adjustment the idea behind the zone adjustment process is no longer valid.

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I asked about the sampler because I believe one pixel is not representative and that 3x3 or 5x5 pixels is what is needed.

 

The object of the exercise is to change one zone to another, selected zone and this is done by changing the L value to another, predetermined value at the sampled point. Therefore, it is necessary to follow the change in L value that occurs when the curve is manipulated as demonstrated in the video.

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Yeah 3x3 would be better 

therefore I posted the link to the request 

 

Yeah just place a Sampler (Drag and drop) and change it to display LAB and add a curves adjustment, select L channel, use the picker at the place of the sampler and drag up/down

 

you move the picker of the curves adjustment and read the value from the info panel 

 

hope that helps 

 

 

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Unless I am doing something stupid two things happen. Frstly, when the picker is placed over the sampler and moved, the L reading for the sampler changes and you have to move the sampler in order for the small circle to appear on the curve which marks where the manipulation is needed. Secondly, the values read when the picker moves appear to be the values  at the cursor as it moves within the curves adjustment layer.

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1 hour ago, Littletank said:

Unless I am doing something stupid two things happen. Frstly, when the picker is placed over the sampler and moved, the L reading for the sampler changes and you have to move the sampler in order for the small circle to appear on the curve which marks where the manipulation is needed. Secondly, the values read when the picker moves appear to be the values  at the cursor as it moves within the curves adjustment layer.

here is a short video 

hope this clears it up/ makes it work for you 

zone.mov

 

(I think the A opponent changes because my document is in RGB and not LAB so there are some mapping things going on)

 

 

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53 minutes ago, Littletank said:

Unless I am doing something stupid two things happen. Frstly, when the picker is placed over the sampler and moved, the L reading for the sampler changes and you have to move the sampler in order for the small circle to appear on the curve which marks where the manipulation is needed. Secondly, the values read when the picker moves appear to be the values  at the cursor as it moves within the curves adjustment layer.

I am not sure what you mean by this. To freeze a sampler on a specific pixel, select & drag its target icon from the sampler onto the canvas & position it over the desired pixel. As long as that sampler's target icon is highlighted, its values will not change & the target will appear as a red icon of the same shape on the canvas. But if you select the arrow icon in the sampler, you will switch it to the continuous sampling mode.

 

Note also that you can add as many samplers as you want, & set each of them to Lab, RGB, or whatever by clicking on their half-filled circle icon & choosing from the popup menu. So for example it is possible to have five LAB samplers, four set to sample a single pixel & one set to sample continuously as you move the pointer around on the canvas, like this:

59c505326e8fc_Infopanel.png.c97be014e2c29833f4ec72848f39916c.png

All 3 1.10.8, & all 3 V2.4.1 Mac apps; 2020 iMac 27"; 3.8GHz i7, Radeon Pro 5700, 32GB RAM; macOS 10.15.7
Affinity Photo 
1.10.8; Affinity Designer 1.108; & all 3 V2 apps for iPad; 6th Generation iPad 32 GB; Apple Pencil; iPadOS 15.7

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1 hour ago, MBd said:

Yeah 3x3 would be better 

therefore I posted the link to the request 

Even better, but harder to implement, would be an additional option for a continuously adjustable sample size instead of only those based on specific pixel dimensions. So for example, there could be a red adjustment dot on the loupe, similar in function to the shape ones that change a shape's parameters. Clicking once would temporarily freeze the loupe's position on the canvas so the pointer could be used to alter the loupe's scope ... or something. 297.gif

All 3 1.10.8, & all 3 V2.4.1 Mac apps; 2020 iMac 27"; 3.8GHz i7, Radeon Pro 5700, 32GB RAM; macOS 10.15.7
Affinity Photo 
1.10.8; Affinity Designer 1.108; & all 3 V2 apps for iPad; 6th Generation iPad 32 GB; Apple Pencil; iPadOS 15.7

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