View Full Version : removing Digitalback-Moiré in a trouser.


pure
02-15-2006, 10:17 AM
hi,

any idea how i could remove a digitalback produced moiré?

its in a piece of texture, a trouser. green.
i used selective color but it wont dissapear i tried all channels

if i use blur it gets too soft.

i installed the Phase One De-Moiré. but i cant find it in Photoshop CS2. maybe its for Photoshop 7 only.

thanks

mistermonday
02-15-2006, 10:33 AM
Pure,
It all depends on the nature of the Moire, what solution will be most effective.
Can you post the image?
Regards, Murray

pure
02-15-2006, 10:37 AM
yes

finally discovered why the filter demoirize is not available: i have 2 folders in my Photoshop. "Plug-ins" and german "Zusatzmodule".

so i try this PhaseOne Filter now, ok?

thanks

philbach
02-15-2006, 10:49 AM
Well I improved it some. I converted the file to lab and then used surface blur (Radius-15 and Threshold-38) on both the a and b channels.

pure
02-15-2006, 10:52 AM
ok phil, fine result,
only the original color is gone, which should be preserved.

i tried the Demoirize plugin, it works, but the curves formerly known as moiré are now a little bit darker curves as the trouser.

hm.

mistermonday
02-15-2006, 10:54 AM
Hi Pure,
you are very fortunate with this image because the Moire pattern is in the color, not in the lightness. Convert the image to LAB. Apply a Gaussian Blur of 20 to both the A and B channels. That's all.
Regards, Murray

mistermonday
02-15-2006, 11:08 AM
Pure, was the original color green or tan?
Regards, Murray

pure
02-15-2006, 11:16 AM
green,

i cant convert it, sorry. i am in RGB and have dozens of layers here, so i am always afraid of converting a high res image to LAB back.

i tried the selective color method and reduced it a bit, then i applied the filter "decrease noise" (translated from german? in german its "störungen reduzieren") :hat:

that made it. not perfect but nicer than it was before.

i dont know any better method in the moment to preserve the original color.

thanks

pure
02-15-2006, 11:24 AM
thanks for your help though. i appreciate.

the "Demoirize Filter"
actually if you want to give it a try, its free and very good:
Demoirize Filter from Phase One. sorry doesnt have the URL by hand..

i would like to know why the Demoirize Filter doesnt work mostly. its greyed out. if i select the backgroundimage, it works. and this very good. but selecting any other layer is helpless. its greyed out, i cant select it in Filters palette.

any idea? maybe someone who has it?

mistermonday
02-15-2006, 11:31 AM
Pure,
I understand your concern about converting multilayers to LAB - some may not survive the transition. What about Ctrl + Alt + Shift + E to make a composite layer. Copy it into a new image, convert to LAB and paste the result back into your master.

As for the color problem, there are other ways to get rid of the Moire but still using LAB.

Just use the L channel and discard the A&B. Add a new blank layer, fill it with a color, change the layer blend mode to color.

You might be able to get rid of the Moire in RGB by doing some Channel blending but this will be a lot more effort.

Regards, Murray

studioj
02-15-2006, 12:00 PM
Have you tried a 50% soft brush with the color you want and blending mode COLOR?

I think it could give something nice.

I'll try.

studioj
02-15-2006, 12:02 PM
Yeap, it works, 15 seconds job

1. Use the brush size 100 pixels
2. Adjust blending mode to COLOR
3. Adjust opacity to 50%
4. Use the color picker to pick the color you wish.
5. Paint over the moire

Kraellin
02-15-2006, 12:08 PM
this is very, very simple and fast.

duplicate the background layer.
add a new blank raster layer above the duplicate.
pick a color matching the part you want. in this case, a somewhat darker color of the greenish pants.
fill the blank raster layer with that color. 100% opacity. 100% density.
set this raster layer to blend mode 'color' or 'color L' (the color L is specific to paint shop pro and the L means legacy).

merge all layers and save.

craig

pure
02-15-2006, 12:09 PM
mistermonday your right, i forgot to mix down and do LAB. sorry.
i tried it, but i couldn follow your method.


i am trying studios method now. seems to be very good from reading, i understand. now practicing it..

thanks

pure
02-15-2006, 12:13 PM
kraellin, what is a raster layer?
you mean a full blank layer?

pure
02-15-2006, 12:17 PM
sorry kraelin didnt work. the trouser is colored then only. but still curves there.
maybe i dont know how you create that raster. i filled a blank layer with a color, is that a raster layer?

trying studios now.

pure
02-15-2006, 12:19 PM
Yeap, it works, 15 seconds job

1. Use the brush size 100 pixels
2. Adjust blending mode to COLOR
3. Adjust opacity to 50%
4. Use the color picker to pick the color you wish.
5. Paint over the moire

on the duplicate painting or on a new layer, blank?

NancyJ
02-15-2006, 12:20 PM
Just out of curiousity I wondered what would happen if I used ByRo's DeGrunge technique (http://retouchpro.com/tutorials/?m=show&id=213). Worked out pretty well - you can also use it to get rid of the crease, should you so wish.

studioj
02-15-2006, 12:22 PM
I used the same layer Pure, je, it's the simple's way.

Remember, I have to work fast always, so, if you want the simple's way, I could bring it ;)

Kraellin
02-15-2006, 12:55 PM
pure,

yes, just a normal blank layer. there are two types of layers or modes you can work in in most paint programs, raster and vector. raster is the one we mostly use. it's just a basic bitmap mode.

make sure if you use the fill layer that you set the fill layer's blend mode to 'color'. it worked fine in Paint Shop Pro 10.

craig

bart_hickman
02-15-2006, 01:51 PM
You don't need to convert to Lab to get access to the color information. Since it's in many layers, simply make a merged duplicate of your image into a new layer, do the gaussian blur on that, set the blend mode to color. For optimum results, I'd erase or mask this blurred color layer everywhere except where there's moire--no sense in blurring the color information in parts of the image where it's not needed.

Bart

mistermonday
02-15-2006, 01:53 PM
Pure, I would like to retract part of what I said above regarding RGB. If you wish to get rid of the Moire in RGB, duplicate the layer. Then do Image>Adjust>Channel Mixer. Set the Red to 40%, Green to 50%, and Blue to 10% AND check the monochrome box. Now fill with color as noted in a number of posts above.
Regards, Murray

Peter S
02-15-2006, 03:46 PM
You could try Russell Browns way.
http://www.russellbrown.com/tips_tech.html
Scroll down to "Moiré Go Away" it looks very good and describes exactly what you want to do using channels, so you don't loose any pixels.
I have not tried it myself but as soon as the occasion arises I will.

Hope this helps

Peter

pure
02-17-2006, 08:43 AM
thanks

i will try that later, what you said in the last 3 posts..
had to upload the image to my client. i left a few uncolored curved lines, but the moiré color is gone anyway – thanks due your help

yes the moire is really good to remove. but then there are weird curves, where the moire are stayed/have stayed on. like bezier curves in grey. i cant explain, but i tried so much to remove it. i had to dodge and burn it manually. a few stayed, but i can improve next week or so.

:wavey:

regards

peter