Moiré effect.

[Trakoko]

i wanted to print the picture, but it is too sharp and has a moiré effect. 16000x12000 pixels
what can I do?

 

[thebestcpu]

HI @Trakoko

Here are a few thoughts.


- Seeing Moiré on your screen at sub 100% magnification does not mean you will see Morié when you print. I would first suggest that you print the image (or a smaller portion at the proportioned same size as the full print and see if you have an issue

- Another approach is to downsize the image to the number of pixels that you would be printing at e.g. 240 to 300 ppi for the size of print your are going to make and again try a sampling

- If the above does not work you could add a very small amount of box or Gaussian blur only to the level not to see it in print

Hope these suggestions help
John Wheeler

 

[Trakoko]

Thank You,

to use Gaussian blur and to downsize is a good idea. My problem is the edge.

 

[ex_teacher]

HI @Trakoko

Here are a few thoughts.


- Seeing Moiré on your screen at sub 100% magnification does not mean you will see Morié when you print. I would first suggest that you print the image (or a smaller portion at the proportioned same size as the full print and see if you have an issue

- Another approach is to downsize the image to the number of pixels that you would be printing at e.g. 240 to 300 ppi for the size of print your are going to make and again try a sampling

- If the above does not work you could add a very small amount of box or Gaussian blur only to the level not to see it in print

Hope these suggestions help
John Wheeler

I’m going to reinforce/expand on what John said.

All printer driver software (as in what comes with the printer) resamples the image when you are printing to the ‘native resolution’ of that printer. They also then dither the various color inks to produce all the colors in the image. Typically this native resolution is 720 for Epson printers and 600 for many others. Unfortunately these drivers do not do a particularly good job in certain situations, especially with moiré, I’ll restate what John said about viewing at 100% on screen to rule out the moiré is not in the image itself.

Again note that John said to use 300 or 240 ppi. It isn’t a coincidence that 240 is an even fraction of 720 and 300 is an even fraction of 600. In almost all instances this will alleviant introducing moiré but in really problematic images the higher resolution can help.

Before using a blur (which works but has it own issue of losing sharpness) try up-sampling to 720 or 600 as appropriate and then view on screen to check the results at 100%. Photoshop has various resampling methods and regardless of the on-screen suggestions…use the method that works best…again viewed at 100%.

And… Check out this tutorial:
https://design.tutsplus.com/tutorials/how-to-fix-moire-pattern-in-photoshop--cms-41614

On a entirely different note, if you created the image yourself and the moiré is in the source file, a camera without an AA (anti-aliasing ) filter on its sensor can help greatly.

 

[thebestcpu]

Great additions @ex_teacher

I can't tell for sure without the original image, yet my best guess is that @Trakoko 's image is not the Sensor induced Moiré when the image pattern is close in size (or multiple of size) of the sensor Bayer Array photosensors. Rather, it is what we both have described is the pattern frequency being close to the monitors pixel spacing and likely a false Moiré (not existent at 100% viewing).

For Moiré that is caused by the Sensor in the camera (typically with color Moiré and sometimes also with luminosity array added in, I include the link to a tutorial in 2011 on how to eliminate both the Color Moiré and the Luminosity Moiré in a Vimeo video:

A New Way to Remove Moiré from 2011

I posted some stills in a PSGurus post in 2020 at the following link as well:

A New Way to Remove Moiré PSG post with still images

The Moiré sliders in Lightroom, ACR, and the Camera Raw Filter I have found are very good at removing the color Moiré and less so for the times when there is also Luminosity Moiré.

Just another option for those times when sensor Moiré raises its head which fortunately with the higher resolution sensors is a lot less often.

Thanks again for you detailed additions in your post above
John Wheeler