I don't succeed to download an image to 300 DPI

[Paul]

Hi,

I'm a beginner in the field. Please help me solve a problem. I have a 2500x3500px image, which I have uploaded in GIMP, to make part of it transparent. Then I wanted it to be downloaded with 300 DPI. Although I set the "Scale Image" to 300 DPI, when I downloaded it, I only had a 120 DPI image.
I made several attempts but to no avail,  GIMP refuse to download the image at 300 DPI.
Where am I going wrong?
Thank you.

[rich2005]

(02-28-2024, 02:10 AM)Paul Wrote: Hi,

I'm a beginner in the field. Please help me solve a problem. I have a 2500x3500px image, which I have uploaded in GIMP, to make part of it transparent. Then I wanted it to be downloaded with 300 DPI. Although I set the "Scale Image" to 300 DPI, when I downloaded it, I only had a 120 DPI image.
I made several attempts but to no avail,  GIMP refuse to download the image at 300 DPI.
Where am I going wrong?
Thank you.

Scale is the wrong tool for this.  Gimp works in pixels 2500x3500 is constant regardless of ppi(dpi). The only effect is when you come to print, the printer will use the ppi to size the print.

Open your image, do what ever is required. 
Use Image -> Print Size. Set the units to pixels/in (if required, some will have pixels/mm) Change the x resolution and y resolution to 300.
Save as a Gimp .xcf file or Export as a png to retain the transparency. Make sure Save resolution is ticked in the png export dialouge.

[Ofnuts]

What Rich says. For more info see https://www.gimp-forum.net/Thread-Image-size-in-Gimp

[Paul]

(02-28-2024, 08:25 AM)rich2005 Wrote:

(02-28-2024, 02:10 AM)Paul Wrote: Hi,

I'm a beginner in the field. Please help me solve a problem. I have a 2500x3500px image, which I have uploaded in GIMP, to make part of it transparent. Then I wanted it to be downloaded with 300 DPI. Although I set the "Scale Image" to 300 DPI, when I downloaded it, I only had a 120 DPI image.
I made several attempts but to no avail,  GIMP refuse to download the image at 300 DPI.
Where am I going wrong?
Thank you.

Scale is the wrong tool for this.  Gimp works in pixels 2500x3500 is constant regardless of ppi(dpi). The only effect is when you come to print, the printer will use the ppi to size the print.

Open your image, do what ever is required. 
Use Image -> Print Size. Set the units to pixels/in (if required, some will have pixels/mm) Change the x resolution and y resolution to 300.
Save as a Gimp .xcf file or Export as a png to retain the transparency. Make sure Save resolution is ticked in the png export dialouge.

When I wrote my request to you, I omitted to tell you that I also checked "Print Size", where I set 300 DPI and then followed the steps you described.
But I got the same result.
The resulting image was still 120 DPI.

[Ofnuts]

(02-28-2024, 10:38 PM)Paul Wrote:

(02-28-2024, 08:25 AM)rich2005 Wrote:

(02-28-2024, 02:10 AM)Paul Wrote: Hi,

I'm a beginner in the field. Please help me solve a problem. I have a 2500x3500px image, which I have uploaded in GIMP, to make part of it transparent. Then I wanted it to be downloaded with 300 DPI. Although I set the "Scale Image" to 300 DPI, when I downloaded it, I only had a 120 DPI image.
I made several attempts but to no avail,  GIMP refuse to download the image at 300 DPI.
Where am I going wrong?
Thank you.

Scale is the wrong tool for this.  Gimp works in pixels 2500x3500 is constant regardless of ppi(dpi). The only effect is when you come to print, the printer will use the ppi to size the print.

Open your image, do what ever is required. 
Use Image -> Print Size. Set the units to pixels/in (if required, some will have pixels/mm) Change the x resolution and y resolution to 300.
Save as a Gimp .xcf file or Export as a png to retain the transparency. Make sure Save resolution is ticked in the png export dialouge.

When I wrote my request to you, I omitted to tell you that I also checked "Print Size", where I set 300 DPI and then followed the steps you described.
But I got the same result.
The resulting image was still 120 DPI.

What tells you that the image is still 120DPI?

[Paul]

(02-28-2024, 11:40 PM)Ofnuts Wrote:

(02-28-2024, 10:38 PM)Paul Wrote:

(02-28-2024, 08:25 AM)rich2005 Wrote: Scale is the wrong tool for this.  Gimp works in pixels 2500x3500 is constant regardless of ppi(dpi). The only effect is when you come to print, the printer will use the ppi to size the print.

Open your image, do what ever is required. 
Use Image -> Print Size. Set the units to pixels/in (if required, some will have pixels/mm) Change the x resolution and y resolution to 300.
Save as a Gimp .xcf file or Export as a png to retain the transparency. Make sure Save resolution is ticked in the png export dialouge.

When I wrote my request to you, I omitted to tell you that I also checked "Print Size", where I set 300 DPI and then followed the steps you described.
But I got the same result.
The resulting image was still 120 DPI.

What tells you that the image is still 120DPI?

That it is not 300 DPI?

[Ofnuts]

(02-29-2024, 12:48 AM)Paul Wrote:

(02-28-2024, 11:40 PM)Ofnuts Wrote:

(02-28-2024, 10:38 PM)Paul Wrote: When I wrote my request to you, I omitted to tell you that I also checked "Print Size", where I set 300 DPI and then followed the steps you described.
But I got the same result.
The resulting image was still 120 DPI.

What tells you that the image is still 120DPI?

That it is not 300 DPI?

"Not 300DPI" isn't the same as "120DPI". And how do you tell it is not 300DPI? Where/how do you get a measure or report of the actual DPI?

[rich2005]

@ Paul

Please have a look at this little (1 and a bit minute) video https://youtu.be/ay2tw5S1S8E

What it shows:
Open jpeg image, and add transparency, cut area.
Check resolution in Image -> Image Properties
Change resolution Image -> Print Size
Have a look at Image properties again.
Export as a png to keep the transparency
close and reopen and check properties again.

The question is, what do you do that is essentially different ?