Troubles with canvas sizing in inches

[Tytagartist]

So,I was going to start a new project and I went to go put in my dimensions for the canvas in inches to start my project but each time I type in the exact dimensions it decided to round the number instead. Is there something I'm doing wrong? I even did maintain aspect ratio and then I tried unclicking it as well with the same results for both.Any advice would be great.

[Rick Brewster]

The canvas size can only be an integer (non-fractional) number of pixels. So even if you type in an "exact" number of inches, it has to be rounded to the nearest pixel size. Because images are stored using pixels, not inches  

[Tytagartist]

8 minutes ago, Rick Brewster said:

The canvas size can only be an integer (non-fractional) number of pixels. So even if you type in an "exact" number of inches, it has to be rounded to the nearest pixel size. Because images are stored using pixels, not inches  

Well photoshop dosnt do that.I only use paint.net because it's not as taxing on my computer and I do really like the functions it has.

[Rick Brewster]

1 hour ago, Tytagartist said:

Well photoshop dosnt do that.I only use paint.net because it's not as taxing on my computer and I do really like the functions it has.

 

Paint.NET isn't Photoshop ¯\_(ツ)_/¯ Unless I'm misunderstanding your initial problem description 

[Tytagartist]

5 hours ago, Rick Brewster said:

 

Paint.NET isn't Photoshop ¯\_(ツ)_/¯ Unless I'm misunderstanding your initial problem description 

No I get that I only really use paint.net because it's less taxing on my computer and I do like what it offers I just wish it would do exact numbers because I need them for the project I'm working on for when I print it out.

[Tactilis]

10 hours ago, Tytagartist said:

11 hours ago, Rick Brewster said:

The canvas size can only be an integer (non-fractional) number of pixels. So even if you type in an "exact" number of inches, it has to be rounded to the nearest pixel size. Because images are stored using pixels, not inches  

 

Well photoshop dosnt do that.

Yes it does because, as stated, the image size can only be a whole number of pixels.
Photoshop is just hiding the fact that it is having to round the entered inches value to create the canvas size in pixels.
 

 

3 hours ago, Tytagartist said:

I just wish it would do exact numbers because I need them for the project I'm working on for when I print it out.

You haven't said what exact Width and Height size you are entering in inches and what Resolution in pixels/inch you have set.

Let's do the maths and understand why the rounding of a fractional pixel is (or is not) significant for your project.

[Tytagartist]

On 2/24/2024 at 5:36 AM, Tactilis said:

Yes it does because, as stated, the image size can only be a whole number of pixels.
Photoshop is just hiding the fact that it is having to round the entered inches value to create the canvas size in pixels.
 

 

You haven't said what exact Width and Height size you are entering in inches and what Resolution in pixels/inch you have set.

Let's do the maths and understand why the rounding of a fractional pixel is (or is not) significant for your project.

It's 5.327x6.753

[Tactilis]

12 hours ago, Tytagartist said:

It's 5.327x6.753

There are two things happening here:

1. The New image dialog's Print size width & height fields allow only 2 decimal places (2dp). So your entered 3dp figures get rounded to 5.33 x 6.75 inches.

 

2. Then, as explained in the comments above, you have the conversion and rounding to an integer number of pixels for the canvas size.

 

Let's do the calculation using paint.net's 2dp rounding and then again using your unrounded 3dp figures:
 

You can see that the difference between your desired 3dp size and the equivalent print size after rounding to to 2dp and to integer pixels is only a few thousandths of an inch.

 

Is that really of any significance for your project?

 

 

 

[Tytagartist]

5 hours ago, Tactilis said:

There are two things happening here:

1. The New image dialog's Print size width & height fields allow only 2 decimal places (2dp). So your entered 3dp figures get rounded to 5.33 x 6.75 inches.

 

2. Then, as explained in the comments above, you have the rounding to an integer number of pixels for the canvas size.

 

Let's do the calculation using paint.net's 2dp rounding and then again using your unrounded 3dp figures:
 

You can see that the difference between your desired 3dp size and the equivalent print size after rounding to to 2dp and to integer pixels is only a few thousandths of an inch.

 

Is that really of any significance for your project?

 

 

 

I'm not sure how accurate it needs to be for gluing it together once I print it out since it's for a dvd slipcover where it has to fit snugly on the dvd box.

[Tactilis]

6 minutes ago, Tytagartist said:

I'm not sure how accurate it needs to be for gluing it together once I print it out since it's for a dvd slipcover where it has to fit snugly on the dvd box.

It assuredly doesn't need to be accurate to a few thousandths of an inch.

You'll be fine just typing in your 3dp inch width and height, letting paint.net round them to 2dp and convert them to pixels. As I showed above, you won't be able to measure the difference.