How to Remove Mega Moiré
Photoshop Tutorial by Jane Conner-ziser
What is moiré and how do you prevent or remove it?
Moiré is a repetitive pattern of wavy lines or circles that occasionally
appear on objects in digital captures. It occurs when fi bers or fi ne
parallel details in an object match the pattern of the imaging chip in the
camera. Some camera companies incorporate anti aliasing fi lters in the
cameras to slightly blur the tiny detail areas of captures, but other
manufacturers prefer not to use them because they don’t want to sacrifi ce
image sharpness. With or without the fi ltering, every digital camera is
capable of creating moiré.
Camera angle, lens focal length, camera position and focus point can all
contribute to moiré so changing any of these in a circumstance where you see
moiré can eliminate it. On the job it's hard to do because you have to view
the images at 100% in order to see it correctly.
So, you can have a great camera and do everything correctly and still see
moiré once in awhile. It can usually be corrected by duplicating the
background, blurring the copy and changing the layer’s blending mode from
Normal to Color, BUT –
Today we had a challenge; some of the most distinctive moiré I’ve ever seen.
I tried everything. Every tried and true method of moiré removal minimised
it somewhat but nothing even came close to an acceptable fi x. In RGB, the
moiré was visible in every color channel. In Lab Color, it was visible in
both color channels PLUS the lightness channel.
However, it is said that perseverance pays off and we weren’t going to let
it go. In the end I combined a couple of diff erent techniques and come up
with one that works consistently every time. Record an action of this – it’s
worth it!
We’re assuming you are working with an RGB fi le.
1. Image / Mode / Lab Color
2. Duplicate the Background
3. Make sure the Background Copy is the active Layer
4. Open the Channels window
5. Click on the Lightness channel to make it the active channel
6. Choose from the Main Menu Bar, Image / Show All Menu Items / Apply Image
Choose the following settings:
Source: will be the name of your fi le
Layer: Background Copy
Channel: b, check Invert
Target: will be the Lightness channel of your fi le name
Blending: Overlay
Opacity: 100% - I TOLD you it was serious moiré!
Check Mask to open additional options
Image: will be the name of your fi le
Layer: Background Copy
Channel: Lightness, check Invert
7. Click OK
8. Click on the Lab Channel (the image becomes color again)
9. Open the Layers window
10. Duplicate the Background Copy (makes Background Copy 2)
11. Filter / Blur / Gaussian Blur – adjust until colors blend; we did 25
pixels
12. Change the Layer Blending Mode from Normal to Color
13. Hold the Shift Key down and tap on the Background Copy so both are
active
14. Open the More Options fly out menu from the upper right corner of the
Layers window and choose to New Group From Layers. Click OK
15. Hold down the Option (or Alt for PC) key and click on the Layer Mask
icon at the bottom of the Layers window. It will be a black mask.
16. Use the Brush tool, Normal mode, 100% opacity, 100% flow to apply White
paint over the moiré. Choose a brush size appropriate for the job.
17. Choose Layer / Flatten Image
18. Image / Mode / RGB
You’re finished!
Desperate times call for desperate measures and I realise this is a
LOT of steps but it worked every time on the father of the groom’s suit in
an entire wedding. By making the action, this rather involved process was
reduced to one click, a quick swab with a brush and one more click to
finish. We’ll be keeping this action just in case we need it again.
I’m going to name it Jane’s Heavy Duty Moiré Murder-cator or
JCz HD MM for short. It can be remembered as
“Jane’s Hard Drive is filled with M&Ms” Just Kidding - Big Smiles!
Thanks!
Jane Conner-ziser
Jane Conner-ziser
Jane is a photographer, digital artist, independent consultant and teacher
for the professional photography industry. With over 25 years of experience,
19 of them in digital imaging and evolving technologies, the techniques Jane
developed for facial retouching and enhancement and portrait painting are
widely emulated by photographers and digital artists worldwide through her
classes and educational products. She participated in Canon’s Explorers of
Light PrintMaster program, is an Adobe Photoshop Expert, a Corel
PainterMaster, an X-rite Coloratti and a Craftsman Photographer of the
Professional Photographers of America. In addition, she is past co-chair for
the Digital and Advanced Imaging Committee for the Professional
Photographers of America.
