I just hate I can't change image size in AP

[Fixx]

without resample. 

 

 

Numbers just don't keep. Have to open Photoshop for this simple operation.

[Guest]

Hi Fixx,

 

Seen on another forum:

Indicate the desired width and then click on the "height" window.

The height will automatically adjust.

I hope that helps.

[Fixx]

nah, dpi value does not change.

[Guest]

Sorry that it does not work for you, I put the link where I saw the info:

 

http://www.affinity-forum.fr/viewtopic.php?id=686

[R C-R]

nah, dpi value does not change.

For me in the Mac version, if I uncheck "Resample" the only thing I can change is DPI & Units. And if the unit type is a distance value, the width & height values do not update in the dialog box -- it is as if it is using pixels as the basis for the display for all unit types & just calculating distance units (inches, mm, etc.) from that. Since changing DPI without resampling does not change the number of pixels, neither do the distance units.

 

But they do change in the document, because the ruler readjusts as soon as the "Resize" button is clicked & the dialog is dismissed.

[Fixx]

Well, this is a well known defect. Possibly I should stop worrying about resample and just resample away, regardless the slight quality loss that happens every time I change image dimensions. At the moment though it is not possible to set exact print dimensions without resampling the image.

[toltec]

How can you change a documents pixel size without resampling ? I don't even think Adobe can manage that  :o

 

If a file has 300 pixels x 300 pixels and you make it 200 pixels x 200 pixels Affinity (or Photoshop) has to "resample" by throwing away some pixels (100 in this case)  to convert from 300 to 200. Same situation when you go up in pixels.

 

DPI only counts with printing and the DPI setting in Affinity is only there because people are obsessed with DPI in images where they are irrelevant. Except in printing, as I said. The pixels are all that matter. If you need a 2" x 2" file in a page at 300 PPI you can use the DPI setting to help you work out that 300 x 2 = 600. 

 

A 1200 x 1200 pixel image can be 2" x 2" at 600 DPI, 4" x 4" at 300 DPI or 12" x 12" at 100 DPI. You can set any one if AP if you want but It still has the same number of pixels, which is all that matters. 

 

When you know how many pixels you need, set that and ignore DPI.

[R C-R]

toltec,

 

The point (at least for me) is it would sometimes be convenient to be able to set the size in inches, mm, or whatever without having to calculate the appropriate DPI, or alternately to see the resulting change in size in the selected units when changing the DPI field.

 

I know the pixel dimensions won't change without resampling, but since the DPI & print size are interrelated, it would be nice if the dialog box showed that.

[MEB]

Hi Fixx, 

Currently Affinity Photo doesn't calculate the required dpi for specific print dimensions when resampled is unchecked. It only does the other way around: the dimensions you will get when you set a specific dpi.

[R C-R]

Hi Fixx, 

Currently Affinity Photo doesn't calculate the required dpi for specific print dimensions when resampled is unchecked. It only does the other way around: the dimensions you will get when you set a specific dpi (resample disabled).

For me, it does not do that either. For example, I have a 400 x 400 px image open with the document DPI set to 72. I open the Resize Document window, uncheck Resample, & switch the units from px to inches. The size (now greyed out) shows 5.556 in for w & h.

 

I change the DPI to 100 but the size in inches does not change. When I close the window & reopen it, I do get the expected 4 in values, but while the window is open, the dimensions do not update. Like I said, it is as if the window's size values are based on the px dimensions, even when the units are switched to distance ones (like inches, mm, or anything other than px).

[MEB]

R C-R

The "resample disabled" between parenthesis at the end in my last reply was a mistake. It should not be there. I've removed it from the post above to avoid more confusion.

This is possible with a small trick: change the dimensions to cm or whatever unit you want - keep resample checked - and set the dpi you want: the units will remain the same while you adjust the dpi. Then untick the resample box and tick it again - the dimension fields will update to reflect the adjusted dpi as you toggle the resample checkbox. If you don't want to resample the image left the resample checkbox unticked in the end.

[R C-R]

This is possible with a small trick: change the dimensions to cm or whatever unit you want - keep resample checked - and set the dpi you want: the units will remain the same while you adjust the dpi. Then untick the resample box and tick it again - the dimensions field(s) will update to reflect the adjusted dpi.

I suspect the underlined part is a mistake -- if you tick it again, the image will be resampled, which is what we are trying to avoid ... right?

[MEB]

Not exactly. I meant you can tick/untick it to force the update of the fields. Obviously if you don't want to resample the image you have to leave the resample checkbox unticked in the end.

[R C-R]

Not exactly. I meant you can tick/untick it to force the update of the fields. Obviously if you don't want to resample the image you have to leave the resample checkbox unticked in the end.

From what I can tell, it is only necessary to set the DPI with resample ticked & then untick it to force the size fields to update -- so just one untick is needed to make the trick work, which is good. But this trick does not seem to work if you want to change the size fields to force the DPI to update (not that you claimed it did).

 

All this is by way of saying what would be nice is if we did not have to resort to any tricks, that without resample ticked changing any of the fields should update the others. (Obviously, without resampling, the sizes have to remain locked, but everything else should be accessible, not greyed out, & update interactively.)

[MEB]

Yes, you only have to do it once if you know what you want to do, or you can continue doing it if you want to adjust the dpi more times and see the result. I thought that was obvious.

 

But this trick does not seem to work if you want to change the size fields to force the DPI to update (not that you claimed it did).

Se my post #9: Currently Affinity Photo doesn't calculate the required dpi for specific print dimensions when resampled is unchecked

 

 

All this is by way of saying what would be nice is if we did not have to resort to any tricks, that without resample ticked changing any of the fields should update the others. (Obviously, without resampling, the sizes have to remain locked, but everything else should be accessible, not greyed out, & update interactively.)

Yes, it could be improved. I've filled an improvement request for this quite some time ago so maybe some day... The dev teams have been quite busy as you know.

[R C-R]

Se my post #9: Currently Affinity Photo doesn't calculate the required dpi for specific print dimensions when resampled is unchecked

I did see that, which is why I included "(not that you claimed it did)" in my reply to acknowledge that.  :)

 

I think some of the idioms I use are not as clear as they could be. I will try to work on that.

[Ian R]

I'm glad to see this discussion going on. It's been puzzling me how size and pixel density changes behave.

[toltec]

Photo programs all work in pixels, it's us people who use inches or millimetres.

 

In the Document settings, it is best to think of the dpi setting as a calculator. If you set the size in inches, the dpi setting calculates how many pixels are needed to make (for example) a 2" wide image at 300 dpi (600). 

 

If you set the image size in pixels (600), that is Affinity's native "language", so it does not need to make any calculations and the dpi is totally ignored (when it comes to resolution). DPI will not affect the number of pixels (image resolution) in any way, shape or form. 

 

However, you may want to put the image into a page layout program like Designer (lets say, set to 300 dpi) and based on pages using inches. In that case, if you set the image to 2 inches at 300 dpi (rather than just 600 pixels) the image will be the same resolution but, Designer will know your 600 dpi image should be 2 inches wide and will size it accordingly. If you just use pixels and don't set a dpi setting (or use the wrong one) the image will be inserted based on number of pixels, screen resolution etc. So you will have to resize it to 2 inches manually.

 

That is the main benefit of matching inch sizes and dpi settings.