Resize document provides poor quality

[Pikay]

Hi all

I am new to Affinity and have found that resizing an image in Affinity Photo gives very poor quality.

My image (pixel, not vector) must have a resolution of 300 DPI and a size of maximum 8 cm edge length (these are our operational guidelines). The original image has a resolution of 281 DPI and 1965x2835 px.

If I now resize the image via "Resize Document" to 300 DPS and 8 cm (or 945 pixels), the lines suddenly become blurred. No matter which setting I choose, Lanczos 3 non-separable or any other, the results are all not clean and satisfactory.

I have attached the original image and the adjusted version with 300 DPI and 655x945 px (Lanczos 3 non-separable). I hope someone can help me and solve my problem....

 

Best regards

Pikay

 

 

[John Rostron]

Hello @Pikay, and welcome to the forums.

Lanczos is not the optimal algorithm for line art. It is better for photographs. Try using one of the other algorithms to see if one of those gives you a better result.

John

[Pikay]

Hello @John Rostronand thank you for your quick reply.

Unfortunately none of the other options leads to a better result. I'm actually all out of ideas...

[User_783649]

@Pikay Couple of questions to clarify things.

1. In Affinity Photo toolbar what zoom level do you see next to filename after you resize your image?

2. What is the resolution of your monitor?

3. And if you're on Windows – what UI scaling percentage you have in system settings? If you're on a Mac – what scaled resolution do you have set in System Preferences?

[Pikay]

10 minutes ago, Alex M said:

@Pikay Couple of questions to clarify things.

1. In Affinity Photo toolbar what zoom level do you see next to filename after you resize your image?

2. What is the resolution of your monitor?

3. And if you're on Windows – what UI scaling percentage you have in system settings? If you're on a Mac – what scaled resolution do you have set in System Preferences?

1. Before resizing 39.2 %, after resizing 117.6%

2. 3440x1440

3. 100%

4 minutes ago, BofG said:

Presumably someone has the original vector file - if you want the best quality output you really should be starting from that file.

Unfortunately we get all different kind of images, so I have to work with what I get.

[User_783649]

Just now, Pikay said:

1. Before resizing 39.2 %, after resizing 117.6%

2. 3440x1440

3. 100%

Try pressing Ctrl+1 to set zoom level to 100%. Is image better now?

One thing that Affinity Photo does really bad is that it distorts image roughly on any intermediate odd zoom levels between 100% and 200%.

Try to avoid values like 117.6%.

[Komatös]

@Pikay

Hope that helps!

I've scaled with GigaPixel AI and vectorized to svg.

 

Original-downscaled 8 cm at 300 dpi.svg

[Palatino]

1 hour ago, Pikay said:

I have attached the original image and the adjusted version with 300 DPI and 655x945 px (Lanczos 3 non-separable). I hope someone can help me and solve my problem....

In such a case it may be useful to scale up first and then scale back to the desired size (Bilinear).

2835 px –> 4725 px –> 945 px 
(945 px x 5 = 4725 px)

 

[Pikay]

1 hour ago, Komatös said:

@Pikay

Hope that helps!

I've scaled with GigaPixel AI and vectorized to svg.

 

Original-downscaled 8 cm at 300 dpi.svg 75.34 kB · 1 download

Thank you for your work, but that doesn't help me with all the other images I have to work with.

 

I've worked with Photoshop for years but due to new company policy, we're not allowed to anymore.

 

1 hour ago, Alex M said:

Try pressing Ctrl+1 to set zoom level to 100%. Is image better now?

One thing that Affinity Photo does really bad is that it distorts image roughly on any intermediate odd zoom levels between 100% and 200%.

Try to avoid values like 117.6%.

Thanks for your advice, I'm seasoned with Photoshop where the commands (Ctrl+1, Ctrl+0 etc.) are more or less the same.

 

1 hour ago, Palatino said:

In such a case it may be useful to scale up first and then scale back to the desired size (Bilinear).

2835 px –> 4725 px –> 945 px 
(945 px x 5 = 4725 px)

Wow okay, this looks really like it should! I will try it right now and let you know.

 

 

[Pikay]

1 hour ago, Palatino said:

In such a case it may be useful to scale up first and then scale back to the desired size (Bilinear).

2835 px –> 4725 px –> 945 px 
(945 px x 5 = 4725 px)

That really did the trick! You're my saviour, thank you so very much!

 

As well as all the others of you with your suggestions, approches and ideas. I'm greatful!

 

Have a good day/night and see you soon (with my next problem^^).

 

Bye you guys