How do I export 2" to 2" image? (1:1) I can only export pixels, I want inches...

[aztec.mc]

In other software my 2" image will export as a 2" image, easy... I'm new to Designer in Windows 10 and export ONLY has pixels, which can be manipulated by DPI, but the image will never export as 2" inches.

Specific: When I export my 2" image it forces me to use pixels. I tried the export persona and it's the same thing, at 1x it still uses pixels... The only thing I do is work with inches, please help.

[Gear maker]

1 hour ago, aztec.mc said:

In other software my 2" image will export as a 2" image, easy... I'm new to Designer in Windows 10 and export ONLY has pixels, which can be manipulated by DPI, but the image will never export as 2" inches.

Specific: When I export my 2" image it forces me to use pixels. I tried the export persona and it's the same thing, at 1x it still uses pixels... The only thing I do is work with inches, please help.

I never tried to force it before.  Most dimensions in AD you can force by putting in the dimension and unit like 2" or 2 in.  But you are right you can't in the export.  I'm on a mac so we've tried both systems.  You'll just have to trust that the default that comes up will be whatever you have used to create the drawing.  I guess you could always do the math 72dpi * 2" = 144 px or  300dpi * 2"=600 px.  Look on the bright side it would be much more difficult to calculate accurately if you were using millimeters.  The output file will be the same either way.  When you look at the metadata of a jpg or png it always shows the pixel size.  An svg always has the pixel size stored in it.  I'm not talking about just the export files, any jpg, png, or svg I've looked at from any application.  I would guess that's why it was set up this way.

[walt.farrell]

4 minutes ago, Gear maker said:

Most dimensions in AD you can force by putting in the dimension and unit like 2" or 2 in.  But you are right you can't in the export. 

You can't see the dimension in inches, in the Export dialog, but you can specify the size in inches, and Affinity will calculate the number of pixels for you based on the DPI.

[Gear maker]

Hi Walt, it doesn't work.  If I take a 2" x 300 dpi drawing and open export, then set the Size to be say 100 px and hit return, then decide to put in 2" it comes back to 100 px, not 600px.  It's also surrounded by a red box to show it didn't work.

[walt.farrell]

43 minutes ago, Gear maker said:

Hi Walt, it doesn't work.  If I take a 2" x 300 dpi drawing and open export, then set the Size to be say 100 px and hit return, then decide to put in 2" it comes back to 100 px, not 600px.  It's also surrounded by a red box to show it didn't work.

Where in the discussion have we been talking about changing the size multiple times? 

Wasn't the OP wanting to export an image using inch units? Why are you specifying a different px value before trying to use inches? (That may be a different issue, not I don't think it's what aztec.mc was asking about.)

Or, what am I missing?

[aztec.mc]

this isn’t what i was hoping for... the fact i can’t export 1:1 image in a ‘Pro Design’ software is terrifying, considering i’m now fully invested & training here now...

my goal (which i’m used to my entire Life) is to export 2” file to 2” PNG or SVG. when i open file it will always be 2” in any program.

in AD when i export 2” it forces me to choose pixels in PNG or SVG. when i open this file in any program it is always like 8.66” AFTER i convert from pixels to inch. 

(yes i can manually resize to 2” and dimensions will be correct, but i dont want to manually convert ALL of my work in ALL programs, every time.)

if its not possible to save to inches, idk what i’m going to do... but is there any chance of adding this feature in export??

[GarryP]

I just created a 2×2in document at 300 PPI in Designer, added two triangle layers to ‘fill’ the canvas extents, exported it as an SVG (for export), imported it into Inkscape at 300 PPI and the imported object is reported as being 6.25×6.25 in.
This doesn’t seem correct to me but is slightly different to what aztec.mc gets (6.25in rather than 8.66in).
See attached screen grab.
P.S. Importing the SVG into Scribus 1.4.6 gives me an object that is 8.33×8.33in.

[John Rostron]

I created a 2in by 2in AD document, with a dpi of 72. I then exported it as a  .png  putting 2in in each size boxes. I then opened it in various applications:

In Affinity Photo: Size was 2in by 2in or 144px by 144px, dpi was 72.

Corel Paint: Size was 2in by 2in or 144px by 144px, dpi was 72,

Inkscape: Size was 2in by 2in or 192px by 192px, suggesting a dpi of 96, Inkscape asked what dpi to use when importing, that in the file (which should have been 72dpi) or the Inkscape default 

I then repeated this exporting from Designer as .svg (specifying 72dpi for any rasters):

In Affinity Photo: Size was 2in by 2in or 144px by 144px, dpi was 72. 

In Affinity Designer, I imported the .svg and then exported the .svg file  to .png, and it exported as 144px by 144px. This loaded into Photo as 144x144 at 72dpi. However the image was corrupted!

In Inkscape, Size was 463 by  341 the resolution was given as 96dpi. The image also seems to have acquired an extra point at the end.

In Corel Draw X7: Size was 2480 by 3508px or 8.27x11.69in implying a resolution of 300dpi. It also had the extra point. It did not give me an option to choose any other dpi.

My interpretation of all this is that the metadata in any image file does not specify the size in physical units (such as inches). It does, however, include the pixel dimensions of the image and the resolution (in dpi). When the image is loaded into an Application, the application does the sums. For inches it simply divides the number of pixels by the dpi. I think that Inkscape, despite it asking what dpi to use, imposes its own default dpi. Same goes for Corel Draw.

From your point of view, provided that any software exports an image in your desired pixel size and dpi, that should be enough, especially as most apps allow you to specify the size in the physical units of your choice. The app will use the dpi to calculate the equivalence.

John

[walt.farrell]

3 hours ago, GarryP said:

I just created a 2×2in document at 300 PPI in Designer, added two triangle layers to ‘fill’ the canvas extents, exported it as an SVG (for export), imported it into Inkscape at 300 PPI and the imported object is reported as being 6.25×6.25 in.
This doesn’t seem correct to me but is slightly different to what aztec.mc gets (6.25in rather than 8.66in).

Make your file 72 DPI, not 300.

SVG files are assumed to be 72 DPI, if I remember correctly, and if the source Affinity file is not 72 DPI it is scaled by Affinity when creating the file.

[GarryP]

Creating a new 2×2in document at 72 PPI, adding two similar triangles to my earlier one, exporting as SVG (for export) and importing into Inkscape at 72 PPI gives me an object which is 1.5×1.5in (see attached image). That’s not quite right either. Am I missing some other step, or doing a step wrong?

Edit: Ah, hang on, didn’t see John’s explanation above. Using 96 PPI in both applications does the trick for me.

 

Edited July 19, 2020 by GarryP
It works now.

[Alfred]

4 hours ago, GarryP said:

I just created a 2×2in document at 300 PPI in Designer, added two triangle layers to ‘fill’ the canvas extents, exported it as an SVG (for export), imported it into Inkscape at 300 PPI and the imported object is reported as being 6.25×6.25 in.

2″ × 2″ @ 300 PPI is 600 px × 600 px, which is 6.25″ × 6.25″ @ 96 PPI. Edit: As per @John Rostron’s explanation!

[Gear maker]

14 hours ago, walt.farrell said:

Where in the discussion have we been talking about changing the size multiple times? 

Wasn't the OP wanting to export an image using inch units? Why are you specifying a different px value before trying to use inches? (That may be a different issue, not I don't think it's what aztec.mc was asking about.)

Walt, I was merely pointing out that your statement "but you can specify the size in inches" is not correct.  You can plug in any number of inches and the output will remain the same.  I was just showing that it was ignored, by actually doing a change that would be accepted then using your method to try to change it back.  I thought you would figure that out.  Are you still maintaining that the size can be specified in inches?  If so please explain how it is done.

[A_B_C]

I actually wonder where inches have their place in a file format like PNG. When you take a look at the specification, the PNG format provides for the storage of width and height information, each expressed as a number of pixels, and for the storage of physical pixel dimensions which can often be translated into a pixels-per-inch expression. And of course, you can write a lot of metadata to a PNG file, but even then, I am actually not sure whether the format provides for the storage of the kind of information that the thread starter seems to have in mind. Or I am mistaken about the question itself.

Out of curiosity, I wanted to see what is actually written to a PNG file that is exported from Affinity Designer. So I created a 1 by 1 pixel document at 72 dpi and rendered it to PNG. Affinity Designer correctly wrote the Image Header (IHDR) chunk as well as the Physical Pixel Dimensions (pHYs) chunk. When you look at the exported binary in a hex editor, you will see that the IHDR specifies the size of the image to be 1 by 1 pixels, and the first eight bytes of the pHYs chunk represent the decimal numbers 2835 and 2835, followed by a byte representing the decimal number 1. So according to the specification, we can conclude that the image has a resolution of 2835 px per meter in horizontal direction and 2835 px in vertical direction, that is 72 px per inch in each of these directions.

• http://www.libpng.org/pub/png/book/chapter11.html#png.ch11.div.8

And the embedded metadata seem to tell the same. So it’s a bit puzzling to me what the original question is about. Hmm. 

[walt.farrell]

3 hours ago, Gear maker said:

Are you still maintaining that the size can be specified in inches?  If so please explain how it is done.

Yes, I do.

Here is my document's current size: 1050px by 1050px at 72 DPI:

Here is the initial Export dialog:

I now type "2 in" into the size box, and I get:

Ergo, I can specify the export size in inches.

I can even change it, by then typing "4 in" into the size box, and it becomes 288px (4*72).

(In case it matters, I'm using Photo Beta.)

[Gear maker]

1 hour ago, walt.farrell said:

(In case it matters, I'm using Photo Beta.)

Either it's a windows vs mac issue or a AP vs AD issue:

I'm using beta AD.

Here's my documents original size:

The initial Export dialog:

I typed in "4 in" but didn't hit return yet:  (note the red box)

Pressed return:

Interesting!  FYI jpg did the same thing for me.

[A_B_C]

I also can’t enter inches in the export dialogue. Neither in Designer, nor in Photo on the Mac. I also get the red error indication. So is the basic question just about asking the app to do the math? Well, then I obviously misunderstood.

[R C-R]

1 hour ago, A_B_C said:

I also can’t enter inches in the export dialogue.

Same here.

[walt.farrell]

So, perhaps it is a Mac vs Win issue, and perhaps a bug.

[carl123]

On Windows I can type

2"
2in
2inch
2inches

Do any of those work on a MAC?

[lepr]

44 minutes ago, carl123 said:

On Windows I can type

2"
2in
2inch
2inches

Do any of those work on a MAC?

No

[aztec.mc]

i am able to type "inches" into the export so that's good, but i believe i found the reason for wrong sizes... ALL exports, even persona selection create a PNG that includes all the empty, transparent background. you can see same AI file as PNG exports correctly. (both 2"x2" on 4"x4" transparent background)... so is there a way to turn this OFF? i think we're getting close to a solution here.

[A_B_C]

If I understand you correctly, you would like to crop your image to the non-transparent parts on export while keeping the transparent parts in the original Affinity Designer document. Is that correct? If so, I fear you can do this only by creating a slice in the Export Persona. There is no checkbox that would enable such an option on export.

(Affinity Photo has a menu option to crop to non-transparent parts of an image, but not as a dedicated export option either.)

[markw]

If exporting from the Draw Persona, ‘Design Persona’ or ‘Pixel Persona’, then using the ‘Export selection without background’ setting found in the ‘Area’ options may be of use.
This option will then only export those items currently selected/highlighted in the layers panel.

[A_B_C]

Oh yes, that would be an alternative. 😀

(Personally, I must say I almost never use this option, as I feel it’s prone to errors. You will have to very carefully make your selection to get things exported as you wish.)

[walt.farrell]

1 hour ago, markw said:

If exporting from the Draw Persona,

Terminology Alert: In case you haven't noticed, it's been the Designer Persona since 1.7