How can I resize Pixelart so that every pixel mentains its correct width and height

Question

As example, this example here. Every pixel is taking a 5x5 grid. The selected image in there is 75x75 pixels tall. Now what I did is that I took the 100% and changed it to 80%, 60% and so on, which seemed to work fine.

 

Each time I change it though in this: Putting both on 80%

it looks like this, but sometimes when I hit apply it will either be correct or have not the correct width an height for each pixel. Not sure why that is so.

and yeah this is after I hit apply:

As you can see this is a 80%x80% version, so it's 60x60px but for some reason this one did not mentain the correct pixel size, not really sure why though. If you take a look at the preview though, the selection outline is somehow outside, for some reason. So if I move the selection around it somehow fixes itsself and then if I hit apply it will work properly, not sure why though again.

 

 

Now my question is, how can you resize pixelart so that every pixel mentains its correct width and height, in both for scaling up and scaling it down. In a way where you can precalculate the amount of "pixels" each resized pixel is going to take.

Answer 1

It seems that you are using Nearest Neighbor interpolation, which is the right choice for this operation.

What causes your troubles is probably that you have the Reference point location set to the middle:

Your image is scaled down from 75x75 px to 60x60 px. Since you ask Photoshop to keep the same center, the image is reduced by 7.5 px on all four sides. Since we can't have half pixels and Nearest Neighbor doesn't anti-alias the image, you get that unwanted chunky scaling as a result of pixel rounding.

Instead try setting the Reference point location to the top left corner: