Hi everyone, I’m Cintia and I’m beginner using Krita. Recently, I have a problem with transformation tool, when I scale an image, it lose a lot of quality, and it’s images of 300pp, so I don’t know why lose so much quality.
I put an example with my own illustration, the first one is unscaled and the other, scaled.
I don’t think that this was normal, so for that reason I’m asking for help. This isn’t the only problem, because the other tools of transformation, such as free transformation, perspective… it lose quality too when I applied at some part of my draw. I have tried to change the filter, with nearest neighbor I have the best results, but, even so, you notice that the line loses quality.
All digital ‘painting’ applications use a grid of pixels to present an image and this limits the possible resolution of the image.
The ppi (pixels per inch) number only has use or meaning for printing images. What matters for resolution and detail is the size of the image in pixels.
When you scale an image down you lose pixels and so you lose resolution:
Any transform produces a new representation by arithmetic/mathematical methods and may or may not look ‘good’ depending on what the image is and how you judge ‘quality’.
Thaks for answer me.
The resolution of this illustration is 2480x3508 pixels. And other images that I used it’s with a similar size and always lose a lot of quality. I have tried to scale the same image with other application (autodesk skeetchbook) and with this program I don’t have this problem, so I understand that is some kind of krita’s problem or that there is something that I do not do well.
In tools options, you can see which algorithm (filter) is applied
You reduce or increase size?
For example, the “nearest neighbor” is not recommended (no antialiasing)
After you can test with “bicubic” or “Lanczos3” for example (the first one will give soft/blurry interpolatio, the second one will be more sharp…)
Concerning other software on which problem doesn’t occurs, I’m curious: can you provide an example on which everything is fine after rezising?
It could help to understand what’s wrong
The original image size is 2480x3508
and the final resized image size is 1080x1080 pixels, i’m resized to this size just as a way of doing an example for what it’s happening always that I tried to scaled an image.
When I rezise the same image (2480x3508) to 1080x1080 in Autodesk Sketchbook this is the result
So the conclussions that I extract from this is that the resized is correctly, but I’m lose quality anyways? Because I’m using 400% zooming and this It will be noticed always. The doubt that I had, and for wich it was so strange to me was that when I resized an image of 2480x3508 lose so much quality by converting it into a smaller size.
Ok my though was right
Did you try to activate Pixel Preview option to see if result is the same than in Krita?
When you resize an image, as @AhabGreybeard explained in his post, you loose pixels (if you reduce size)
When you zoom at 400%, each pixel is rendered on screen with 4pixels width square, so you see heavily the pixels.
By default when zooming with autodesk sketchbook, it try to extrapolate these 4pixels size square, building new pixels (this is what I did with Krita in my 2nd example, I resized image at 80% with a “bell” interpolation-that’s like bicubic or trilinear interplation, a method to add pixels to sooth results)
Applying a filter when zooming in could be a good idea on a gallery software, but not on an editing/painting software because you won’t really see what you have in your image.
