Blurry images when decreasing size?

[MarcoJ]

Hi,

Just made the switch from Photoshop (basic user) and QuarkXpress to Affinity Photo and Publisher. Love the apps!

However there is one thing that I can't seem to figure out even after searching the forums. When I decrease the pixel size of an image, the image gets blurry. I don't know why that is. In Photoshop I've never experienced this.

Here is what I did:

- I took a picture of 96 dpi, 568 x 168 pxiels
- Resized it to 72 dpi, 300 x 89 pixels, resample bilinear
- Save it as JPG at 80% quality

I have enclosed a picture with the results. The non-resized images look about the same for Affinity (left) and Photoshop (right) but the smaller icon by Affinity definitely looks a bit less sharp.

Does anyone have an idea about what I am doing wrong?

Thanks!

Marco

Edited December 30, 2020 by MarcoJ

[John Rostron]

Hello @MarcoJ and welcome to the forums.

When making judgements on sharpness, you should always view your image at 100% zoom. Did you do this?

John

[MarcoJ]

Yes, the images are all 100% zoom. If you download the image and open it at 100% that will be the exact size. 

[John Rostron]

17 hours ago, MarcoJ said:

Yes, the images are all 100% zoom. If you download the image and open it at 100% that will be the exact size. 

To my (ancient) eyes, your two images look the same. You could try a different scaling algorithm, such as Lanczos. Or you could add a little sharpening.

EDIT: I have been advised that Lanczos is not recommended for downsizing

John

[MarcoJ]

Thanks John. Yes, I was told that bilinear is the best method for downsizing.

I have added a zoomed in image of both versions, the Affinity Photo render on the left side and Photoshop on the right. You probably will see the difference here. In Affinity I am definitely missing the clarity that I get in Photoshop. Sure I could sharpen each image after scaling it down, but I hoped Affinity Photo would do an equal quality job out of the box like Photoshop.

Marco

Edited January 1, 2021 by MarcoJ
Typos

[Old Bruce]

This looks like the one on the left was not 'pixel aligned'  hence the increase in fuzziness.

[MarcoJ]

Thanks for your answer Bruce. Not sure what 'pixel aligned' means in this situation. (As said, I'm just a basic user and unfortunately so is my knowledge about these definitions.) I just downsized a JPG image. How do I 'pixel align' this?

[carl123]

2 hours ago, MarcoJ said:

How do I 'pixel align' this?

Check the Transform tab and for all 4 values of X,Y and W,H make sure they are all integer values and have no decimals

If they have decimals just round up/down the value and type it into the relevant box

[PaoloT]

I've tried the various options, and Lanczos has always given me the sharpest results when downsizing. Why am I experiencing this?

Paolo

 

[MarcoJ]

@carl123 - Thanks, I checked and they all have integer values so indeed no decimals.

@PaoloT - I have tried Lanczos (separable) and you are right. That resulted in a sharper image. With the non-separable version the image became a little too jaggy, so I will use Lanczos  separable for downsizing.

Thanks everyone for your help!

Edited January 1, 2021 by MarcoJ

[PaoloT]

On 1/1/2021 at 6:22 PM, MarcoJ said:

I have tried Lanczos (separable) and you are right. That resulted in a sharper image. With the non-separable version the image became a little too jaggy, so I will use Lanczos  separable for downsizing.

I've just done some other down-resizing (printed and handwritten text, black ink on white paper), and the Lanczos (non-separable) option was the most faithful to the original. I would say perfect. The correct option probably varies depending on the original image. This is the same with Photoshop, even if I find the default option in AfPhoto (Bilinear) the one working the worse with my materials.

Paolo