Text Size, DPI, and Screenshot

[RaananaGamer]

I mainly use Affinity Design for creating Help content. Some of that involves taking screenshots and applying labels.

I am using a default screen size for new documents of 1920 x 1080 (pixels).

I set the DPI to 300.

When I try to insert text, it displays way too large.

I have to set the DPI to 72 to get the text to display at the actual size I choose.

 

1. Is this a bug?

2. If I use a low DPI, that seems to degrade the quality and sharpness of the screenshots. How can I get the right size text and not affect the screenshot display?

[walt.farrell]

Can you supply a sample .afdesign document where this happens?

Also, when you say the text displays "way too large" do you mean "larger than the font size you specify"? Or "larger than text in your screenshot"?

[thomaso]

I reckon the issue is not the text size but rather your feeling for the screenshot size as 100%, which you are used to see in much less than 300 dpi. Now, inside a 300 dpi document this screenshot (e.g. 72 dpi) appears too small, compared to its usual appearance on screen. Note that a placed image appears in different size depending on its own dpi AND on the current document dpi. Since screenshots aren't usually saved in 300 dpi they will appear quite small if the document dpi = 300.

In this sample you see the varying image size but maintained text size:

So to fix your issue you would rather adjust the image size than the text size, therefore take a look in the image property in the Toolbar. It will show you the current dpi of the image and it's placed size, relative to your current document's dpi. For instance:

 

 

[RaananaGamer]

I have attached two projects and two outputs.

In the 72 DPI project, the text is at the right size.

In the 300 project, the text is too big. It should be 12 point Arial, but is way bigger than that.

300-proj.afdesign 72-proj.afdesign

[RaananaGamer]

Hi Thomaso, 

First, I appreciate you trying to help. Unfortunately, I simply don't understand your answer. My shortcoming, but there you go.

To my (simple) brain, if I select 12 point Arial, that's what I should see on screen and that's what the output should be. 

Also, if you ignore for one minute whether I am labeling screenshots or not, I need to be able to use 12 point Arial (or whatever size and type of font I want to use) without worrying about the DPI setting. 

[thomaso]

The difference you experience is related to your set unit 'Pixel'. This makes it less obvious that the 2 documents have different dimensions. may appear in different size, relative to the document resolution (dpi) and in another unit than 'Pixel'.

Simple solution:
If you switch (right-click in the rulers crosspoint) from the current, absolute unit 'Pixel' to a relative unit, like 'Millimeter' or 'Inch', you will notice that the documents have different dimensions: compare then the ruler and the zoom level.

So, your text size is 12 pt in both files – you simply so-to-say look at it from a different distance to make their differently large areas appear in same size on screen.

[Fixx]

While your document is 1920X1080 all time, different dpi makes the difference. If you set dpi to 72, physical size is large, 677,33 X 381 mm. There 12 pt text is small compared to page area. If you set dpi to 300, page size is 162,56 X 91,44 mm and 12 pt text covers larger area.

Designer thinks its page always has physical dimensions.

[RaananaGamer]

Thomaso and Fixx, thanks for taking the time to reply.

I (sort of) understand. 

What I still don't get is that both outputs are 1920 x 1080 and you can see the different font sizes. To my way of thinking, DPI should have no effect on the font size, but it clearly does and you are telling me this is not a bug.

At least I know how to work around it.

Thanks again.

[thomaso]

5 minutes ago, RaananaGamer said:

What I still don't get is that both outputs are 1920 x 1080 and you can see the different font sizes. To my way of thinking, DPI should have no effect on the font size,

You can say it's just the way Affinity handles various units. That's why I called above Pixel 'absolute' and Millimeter/Inch 'relative'.

If you prefer to work in Pixels as unit (there may be various reasons) you can avoid the confusion if you use pixels as unit for font size, too. To do so just enter a value and type 'px' behind, then hit the return key as usual.

Another, maybe even easier option, is to un-tick the according check box in the app preferences, this way font size will always appear in your document's unit and the difference will not occur:

 

[Gear maker]

2 hours ago, RaananaGamer said:

I (sort of) understand. 

What I still don't get is that both outputs are 1920 x 1080 and you can see the different font sizes. To my way of thinking, DPI should have no effect on the font size, but it clearly does and you are telling me this is not a bug.

Let's try this explanation, 300 dpi means that 1 inch equals 300 pixels.  A 72 dpi means that an inch equals 1 inch.  So a square 1920 x 1080 at 300 dpi would be 6.4" x 3.6" and at 72 dpi it would be 26.7" x 15".  There are 72 points per inch so 12 points would be about 1/6 of an inch.  In a square 3.6 inches tall 1/6 of an inch would look much larger, than in a square 26.7".

To show this draw a rectangle in both drawings and set the size by typing in the Transform panel the width to be 6.4" and the height to be 3.6" (be sure to specify the units " or in).  Position both rectangles so they have your text about centered.  Drag both rectangle's layers to the bottom of the layer stacks.  Now double click the fingernail of both added rectangles so the rectangles approximately fill the window.  Now the text in both your drawings looks to be the same size.

Does that help?

[walt.farrell]

3 hours ago, RaananaGamer said:

To my way of thinking, DPI should have no effect on the font size, but it clearly does and you are telling me this is not a bug.

Perhaps it will be clearer if you consider using 72 pt text, rather than 12 pt.

At 72 dpi (really, ppi, pixels per inch) your 72 pt text is 72 pixels tall, as (by definition) there are 72 pts per inch and the document has 72 pixels per inch.

At 300 ppi, 72 pt text is still 1 inch tall (by definition), but that means it now is 300 pixels tall.

Suppose you had two images, both 1000 pixels tall, but one at 72 ppi and the other at 300 ppi.

• In the first, your 72 pt text is 72/1000 of the image height.
• In the second, it is 300/1000 of the image height, or 300/72 (approximately 4.17) times larger in comparison with other objects in the image.

[RaananaGamer]

Thomaso, Gear Maker, and Walt Farrell, thank you very much for taking the time to share your knowledge. Slowly but surely I am getting to grips with this. 

[Old Bruce]

8 minutes ago, RaananaGamer said:

Thomaso, Gear Maker, and Walt Farrell, thank you very much for taking the time to share your knowledge. Slowly but surely I am getting to grips with this. 

If you really want to get to grips here is the Wikipedia page which will confuse and confound once you get past the first sentence "Typographic units are the units of measurement used in typography or typesetting." ...

https://en.wikipedia.org/wiki/Typographic_unit

[thomaso]

25 minutes ago, Old Bruce said:

Wikipedia page which will confuse and confound once you get past the first sentence "Typographic units are the units of measurement used in typography or typesetting." ...

Interesting that here the definition simply repeats the term "typographic" to explain it's meaning.

Another, both enlightening and confusing, overview of various typographic units is here:

https://de.wikipedia.org/wiki/Konkordanz_(Schriftmaß)

It mentions even 20 (!) typographic units, with short tooltip* descriptions:
(* unfortunately in German, Polish, Swedish, Ukrainian only)