TestTools

It is the difference between visually smooth (human looks at it) and mathematically smooth (values change only by smallest amount, in one direction plus/minus). It has a good effect up to 8-12 bit color depth, then becomes less useful and the negative side effects are not bearable  any more.
Take a gradient and apply a posterize adjustment. It will smooth visually, but with side effect of dissolving the hard edge.
As you might want to keep the hard edge in certain cases (i do, to produce color tiles in defined steps) it is annoying.
There is a (dirty) trick to get it deactivated: add a layer fx, overlay, but set to 0 opacity. But this leads to rasterization when exporting.
play with the file and adjust the number of colors to compare what looks better.
One possible reason for Affinity to use this forced dithering: even in case your document is RGB/32, most displays even marketed specially for photo editing are 8 bit per color channel only. Only the best go up to 10/12 bit, and often only by dithering in the display. So cheap tricks everywhere. 😂. Good HDR capable displays support more, cheap don’t.
 
 

gradient dither posterize.afdesign

Thanks for making the effort.
My point is not that I need help, now that I know about it.
My point is that, as an educated Windows user, the INTUITIVE way to get help on a topic is to press F1 or go to menu > help. Which works, just not very well.
I think AP would be a little better, if the app would guide you towards the much better online help immediately, instead of forcing you to figure it out.
But I'll rest my case; there are more important things that are hard to figure out intuitively.
 

Greetings everyone,
Although this thread is dated, I'm throwing my hat in here, even if only to keep up with any new insights on this workflow.  I myself have several .afdesign files that are layered, 2D floor plans and are referenced almost daily!  Similar to the original poster, I realize that "true" architectural drawings are out of Affinity's wheelhouse, however, I share the thought that (perhaps with just a few minor tweaks & features) designer really can be useful for this application.
Obviously, these 2D models are not going to cut it for any real architectural work, but for my day-to-day needs, they're a godsend...   
Corporate IT is showing malware on "computer Y" at "wallplate X"?...   Found it.
Bill from accounting forgot his office key...  Found it.
Contractors need a visual for where the new cubicles are being installed?...  Here you go.
To ensure proper scale, I simply used shape tools to "trace over" images of actual floor plans (or created scaled models using sketchup/sweethome and exported to SVG).  While they may not be down-to-the-inch accurate, they're more than capable of providing a scalable reference to suit my needs.
As @hildevert alluded to, there are some minor tweaks that could really add to this functionality.  For example, modals/popovers for supplemental info, the ability to search text strings in layers, and connector elements would all be immensely useful for similar applications of designer.  For the record, I understand and fully appreciate that this is way outside of the software's intended purpose.  For that reason, these are certainly not features I'd bug the developers for.  That being said, as the Affinity suite continues to mature & expand, I'd like to think they'd serve other purposes as well, so I'm simply offering my "+1" for this usage scenario and hopefully adding a bit of clarification.  These docs may have started as a bit of a pet project, but have since become an incredible asset, saving me countless hours over time.  It's hard to put a price on answering "what wall plate is printer X using?" instantly - without having to crawl around under desks with a flashlight!
Just my $.02.  Cheers!
 
3624MKTfloorplan.afdesign

I am not sure if you could have asked a question involving more complexities than when asking how grays are handled in color conversions (and not just in Affinity apps).
I think that color-to-gray conversions in Affinity Photo are handled as kinds of pigment conversions, K inks. That means that they are profile-dependent and vary according to the working (document) RGB and CMYK profiles. So, e.g., when you have R128, G128, B128, you might get a gray value 36 when viewing the color definition in grayscale, which is about mid gray in perceptually handled print-oriented standard grayscale ramp in context of European-oriented print -- basically the same as when you would get Gray value 64 in Photoshop in an identical environment, but in Photoshop would then have symmetry when converting back to color-based profiles.
In Designer and Publisher there is symmetry, so entering R128, G128, B128 in either app, using any color profile and color mode, it seems that you will get 50% Grayscale value, and entering 50% gray will give you R128, G128, B128 when switching the color model. On the other hand, in Designer and Publisher, people coming from Adobe environment expect gray values to be handled and exported as K inks, not as RGB values (possibly converted to four-color CMYK values).
So, I’m not sure what exactly happens here, and why, and hope someone wiser will step in and shed some light on this.
EDIT: Part of the confusion was resolved by realizing that the Affinity apps do not use the same color preferences across the apps, so the different behavior between the apps described above was explained by using Dot Gain 15% as the grayscale profile in Photo, and having the default D50 (basically the same as Gamma 2.2 in PS) active in the other two apps. But the problem with non-symmetry exists in all apps, so whenever you have a profile where e.g. RGB 128, 128, 128 does not give Gray value 50, you get constant conversion of colors when switching between the Gray and RGB color models in the Colors panel (or conflicting readings for the same actual colors, in case you have the lock turned on).
 

The main difference is the gamma curve. Use the scope panel to inspect.
If you use sRGB as reference: scope (Intensity waveform) shows linear response. (and Display P3)

If you import (place) others:
Adobe RGB: 

All remaining:

We may cross-talking a bit. The most important part: we have at least 2 color pickers, and they work differently in case the display or document is not plain sRGB. One is bound to sample inside the document window, the other (in color panel) can sample outside the window, anywhere at the display. 
The difference is: one samples the color values inside the document, the other the result after applying the color profile and converting to the display profile. This may explain your observations.
 
 

Hi @TestTools,
I've had a look at your files. 
The "centred" group it is but it's not centred. By this, I mean the curve/line is "centred" in between 2 pixels. With a 1 px stroke, the edges of your stoke would fall .5 pixels to the left and right of the curve. The easiest way to visualise this is to turn the grid on with 1 px spacing and 1 division. 

Because your edges fall in between the pixels, you would get a blurry gray overall image.
Thanks,
Gabe. 

No. LZW Compression does not affect how something displays or prints. It only affects how the data is stored internally in the file.

You will not be able to have a .5 pixels offset with a raster format. When an image is rendered, you cannot have half pixel white and half black. A pixel can only have 1 value.  
As for the "Align Stroke to" that only works with closed shapes.  Otherwise, you do not have an "inside" or "outside", and it will always be centred. 

You may have to make sure no one has had any tea or coffee as caffeine alters our eyes' visual perception of colour.

https://www.jamesritson.co.uk/tutorials.html

This might help.
I strongly advise to search the forum for all post of James Ritson about EDR / HDR / EXR and read them very carefully.
https://forum.affinity.serif.com/index.php?/search/&q=Exr &quick=1&author=James Ritson&search_and_or=and&sortby=relevancy
 
EXR documents are a way of interchanging lossless information and allow unbounded, floating point precision for pixel values, making them ideal for storing HDR content but not particularly for visualising it. EXR files have no real concept of colour space, and are not tagged with colour profiles. The pixel values are usually encoded as linear scene-referred values, as opposed to gamma-corrected values in a particular colour space. This is why colour management solutions like OpenColorIO are typically employed when dealing with EXR files, to ensure accurate colour conversions between the linear values and the intended output space.
 

gamma.aftoolpresetsI provided an explanation what was going wrong for the issue @Rob Chisholm reported in another thread
Unfortunately, Rob never replied.
Please check if the same solution help in your case. If not, please post the image (.afphoto file) and a screenshot showing how the image is display in photo, having the 32 bit preview settings active (included in screenshot).
 
Copy of post in linked thread:
Editing RGB/32 images and converting / exporting has its challenges.
Using the 32 bit preview in “unmanaged”, the image looks good. Changing to “ICC” (In desktop: ICC Display Transform) gives a too bright results.
Generally, you should use “ICC” setting during edit to see how the exported image will look like.
This lets me assume that the RGB/32 version is gamma encoded instead of linear.
Depending on you edit process this can happen intentionally or by mistake.
You can easily convert with help of procedural texture filter.
R=R^2.2 
or R=^(1/2.2)
(same for B and G channel).
As you are using iPad, you need to create the PT filter on Desktop. To help you out here, I uploaded the corrected file. You can copy the layer named "Gamma 2.2" from the file I uploaded, and paste it into other files if required.

Ugh; Just realized that the original RGB16 in 2020 gamut design that I put into a 32bit 2020 gamut attempt has had its RGB numbers shifted before I started making 'filtered' versions. I thought I figured out how to start a new blank page then add the old bits. I have been successful with one set of drawings. Evidently not with the early attempt, so the attachment has been removed.   
Meanwhile, NotMyFault, I have watched and practiced with some basics of Procedural texture filters. Many thanks for the heads up and the design you created and sent. Still can't figure how to make it into the 32bit/P3 or 32bit/2020 gamut. Any clues would be appreciated.

You must not believe everything that someone writes somewhere on the Internet. Serif doesn't say anything like that anywhere, and he never mentioned it.
On the contrary, it provides a free trial version so that everyone can try and verify whether they meet all its requirements before purchasing the product.

I would think it is obvious that I speak only for myself, just as you speak only for yourself.
I am not concerned that any feature request will "trump" any other. I am simply expressing my opinion about which ones are the ones most users are likely to find most useful. You are of course free to express your own opinion about that, but that in no way infringes on my right to do the same thing.
As for asking for feature requests, there is a place for that, but it is not here in the Questions forum.
What I do in these forums primarily is try to the best of my ability to answer questions & help others with theirs. I think I am reasonably successful at that, as evidenced by my 'reputation points,' but of course you may not agree that I have done that very well. I am fine with that.

You can always use adjustment layers to manipulate color values.
Levels allows to divide or multiply by factors up to 100 (based on 1% input accuracy), or add / subtract with same accuracy.
Most flexibility can be achieved by a procedural texture filter borrowed from Photo. This will allow you to set any color values by formulas, using any precision you need.

To my understanding, the documents do not set any absolute brightness in nits. They give a range from 0 to 1, in steps of 8/16 bit resolution or 32 bit floats. Maximum brightness depends on display capabilities.
HDR is limited to range 0 to 100 in Photo, thus limiting your dynamic range.

 

To create maximum dynamic range, use Photo and procedural texture filter RGB=x/300000 with document of 300000 px width.
You may need tricks to create files >256000px as this is a UI limit for creating new files. You can resize later to increase size, but Affinity may refuse to export based on (outdated) restrictions. 

To test out the limits of dynamic range, i created a simple test file:
gradient black to white levels to boost whites by factor 10000 (0.01%) or 10^4 inverse levels to reduce by same factor i duplicated these pairs (keeping them in correct sequence, all boosters down, all reducers on top) until the canvas blew out (except the pixels with almost black value on the left).
You can test yourself by activated the deactivated pair (those in the middle of layer stack)
According to wikipedia, FP32 largest number is in the range of 10^38, thus 9 to 10 boosters should reach/cross the limit of dynamic range.
 
 
 
 
fp32 dr tester.afphoto

Nice work👍🏼
 
As mentioned earlier, you can automate the creation of that color tiles with Affinity Photo, and Procedural texture filters. This might be helpful in future projects, when going from B&W to colored charts.

I used this method to create a chart of all 2^24 RGB colors in 8 bit color channel depth.
 Have a look at the green channel, it shows tiles with steps from black to white (only rotated / mirrored).
To see only green channel in Designer, use a B&W adjustment with green contribution only. In Photo, it would be easier to use the channels panel.
The for formula can be adapted for your use case (e.g. swap x and y, use 1-c to rotate or invert axis).
 
all8bitcolors.afphoto

Hi all, thanks for the feedback so far! (Pinpointing has been renamed )
I'm aiming to get a few more videos done over the next 2-3 weeks (there is of course the Publisher launch to think about as well...). For now, here's a new one that covers how to use the new HDR/EDR display support. EDR support on macOS is limited to the newer MacBook Pro and iMac Pro panels (other models may be supported but I'm not sure), plus the new XDR display that was announced at WWDC. If you have a Windows machine you stand a better chance of using this feature since you just need an HDR-capable display and suitable graphics card. For example, I used my HDR TV at home to get the clips in this video!
 
The video has also been added to the list above. Hope you find it interesting!

Thanks Dan. It's been fun getting into Procedural Textures. People keep on asking for artistic textures like Photoshop - Procedural Textures are better!

I would double 'like' this post if I could, amazing work Tim!
I've passed these links through to the other members of our technical support team here, so we can point new customers in this direction.
Many thanks for the extensive effort you have clearly made with both lesson 1 & 2, it's certainly appreciated and I believe this will have a positive impact on our users looking to dip their toes in the endless possibilities of Procedural Textures

This will likely be due to the active Colour Space for the document, as the Presets in the Procedural Texture dialog are locked to the colour space your document is using.
For example, if you create a new document in CMYK or LAB colour spaces, then open the Procedural Texture dialog, there will be no presets available - however the same window in an RGB document will show the presets  
2021-07-05 12-01-29.mp4

Introduction
 
I don’t understand the mathematics involved either!. Honestly, I have barely the slightest clue about the maths. I also only have a very rudimentary understanding of the syntax for making the equations from scratch.
So, what’s the point? I hear you ask. The answer is that without any understanding of the maths or the syntax, I have managed to work out enough to create artistic filters and macros for all kinds of artistic, lighting and graphic design effects. It’s this PRACTICAL knowledge I want to share in a few tutorials with those who look at the Help section in Affinity, see “var v2=vec2(rx/w/2, ry/h/(b*2)); dir(v2*(a*2))*(c*2)”  and run for hills screaming.
The aim of this first tutorial, is to give an introduction to Affinity Photo’s Procedural Texture filter from absolute scratch. I assume you know absolutely nothing about Procedural Textures. The following tutorials will help you build up enough knowledge to mess around with them and tweak them to make your own.
Why bother with Procedural Textures at all?
 
With procedural textures you can: create textures and patterns which can be used in place of image textures; create textures for displacement maps and create artistic filters; create gradients; lighting effects like highlights and sun spots. I have dozens now which I have used to create chalk, watercolour, cross-hatching, oil paint, grunge, paper and canvas textures… their uses seem only to be limited by your creativity and experimentation, which let's face it, is half the fun!
What are Procedural Textures?
 
Simply put, they are a line, or lines of mathematical formulae in C++ programming language which generate patterns of pixels, BUT DON’T LET THAT SCARE YOU. You DON’T need to understand the maths or coding to use or customise them – I promise!
The clever thing about Procedural Textures is that, because they are generated by maths equations, like vector graphics, they work at all resolutions and sizes of documents. The pattern is only ‘fixed’ as pixels when you hit apply. If you use them as live filters, they are not even fixed then, but remain completely editable AND interchangeable.
Where do I find Procedural Textures?
Go to Filters>Colours>Procedural Texture.  You can also launch them as a Live Filter through Layer>New Live Filter Layer>Colours>Procedural Texture. This option gives you the chance to change or edit the PT later, but lots of Live Filter Layers may slow down your system.
Let’s leap right in! If you’ve opened the Procedural Texture dialogue, close it.
The Procedural Texture Dialogue Explained
Create a new blank document 1920x180 pixels (the size doesn’t matter). Create a new pixel layer by clicking on the chequerboard icon at the bottom of the layer palette or go to Layer>New Layer. Fill this layer with your foreground colour through Edit>Fill with Primary Colour. Procedural Textures seem to need a filled pixel layer to work against.
Let’s look at the Procedural Texture Dialogue in detail:
 

It’s divided into two sections. The top is the Equations section. This is where the equations go which generate the textures. The bottom section is the Custom Inputs section. This where you’ll find various controls for the texture, if it has any.
Equations Section
 
The Equations Section has a drop-down list of presets. This list is actually a library of different textures and patterns divided into categories. The burger icon to the right of the presets drop-down list is where you can create new presets, rename and delete them.
You can also open the Presets Manager by clicking on Manage Presets. Do this now.
 

This is where you can add your own categories, export and import presets, and delete and rename them. You can also drag presets to reorder them or put them into different categories.
Whilst you are here, create a new category and call it Basic Noise or Tutorial Textures. You can rename or delete them later.
Two further things to note are that you can’t rename or delete the default presets, but there is a burger icon next to the categories where you can delete or rename your own or imported ones.
Close the Presets Manager and select the Chequered preset from the Basic Shapes section.

The Equations section has got one equation line which generates squares.
 
TIP: Look at the equation. It has “rx” and “ry” in it. If you see these in any equation (or put them there yourself) you have a click-draggable texture. Click and hold down the mouse in the texture or pattern and drag the mouse around.
 
At the end of the equation line, you have the letters R, G, B, A and an X.
They refer to the red, green blue and alpha (transparency) channels – here R, G and B are active. You don’t need to know anything about channels for now. Just click them on and off, and try them in pairs. The weird thing is that if you want, say, red and white squares you have to turn off the red button! (This is to do with additive colour mixing – a whole other tutorial).
The X at the end of the RGBA line deletes the equation line.
Custom Inputs
 
The Custom Inputs section has got one controller called “Square count” which is set to 25. It’s not the actual number of squares, it multiplies the numbers of squares in the pattern.
The X at the end of the Custom Inputs line deletes the input.
The Custom Inputs section has its own burger icon. This is where you can add sub-presets or variations of textures which you make. Affinity won’t allow you to save sub-presets of the default textures, but it’s worth checking the drop-down list of the default textures as there are some good textures hidden away there – like “Smoke” in the Perlin Noise preset.
That’s it for the basic introduction in the next tutorial (Procedural Textures Tutorial 101.2) we’ll go a little deeper and create a very basic custom texture  - just one word a pair of brackets and one letter, which, with a few tweaks can give you this!
GO TO LESSON 2