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OK... This photo is now officially annoying me...


In the original RAW format this photo looks really good, but in JPG format I get a moire / banding effect on the building 3rd from right (The one with the giant heat sink on the roof)...

The JPGs seem to exhibit this behaviour (albeit slightly differently) at whatever magnification / photo size is used:
Medium Size
Large Size
Original Size

I'd be interested to hear whether this is a "feature" of my monitor, or whether it's a problem with the JPG conversion...

Is there any treatment I can do in PS that will reduce or eliminate this Moire effect??? All input gratefully received...

I also see the slight Moire (Only looked at biggest and embedded image).

No idea how to fix.

Nice shot.

John - the simple answer is no, not really. I find the moire effect happens when the pic is not at 100% on the screen - at 100% it more often or not disappears. If a photo exhibits moire I would be inclined to show it full size as a link. The other answer is to try the shot fom a different angle to minimise the effect.

Seems typical to me, John. AFAIK, the only way to reduce/eliminate it in the original, is to shoot at various focal lengths and apertures to alter the frequency and sharpness. Unfortunately, downsizing the image can still introduce the effect, which then requires softening or moire reduction software tools.

I can see the moire in the small image in your post. Generally, moire in architectural/cityscape shots like yours appears when the horizontal/vertical lines of the buildings line up with the square photocytes (sp?) of the ccd. Unfortunately, thats digital. There are tips and tricks to help alleviate, but really unavoidable in some situations.

A

After a little bit of experimentation, some advice from here and another friend and the article on USM I found this morning, I have come up with a solution for my own problem...

As Chris said, the NEF looked fine when viewed at 100% or 50%, so I reduced the size to 50% as a starting step... and before USM application.

I also noticed that the USM actually made the Moire much worse, so I played about with different settings and found that by increasing the threshhold to 10, I could eliminate most of the Moire while still sharpening the straight edges of the buildings.

It seems to be a lot better to me... What do you think???
Click for a larger version...

John
You may find that the problem will disappear if you make a print. If I get an image with the same problem I use my favourite filter....DELETE

John, some time ago I was looking for a solution to this problem, I came across a photoshop plug-in at this site: http://www.dvp.co.il
Unfortunately it's not free. may be worth a look.

Completely off topic but the big building third from the right with the 'heatsink' style roof is Governer Phillip Tower designed by Denton Corker Marshall. I worked there as a student architect and now have the horrible ability to distinguish pretty much every single one of their buildings.

leek wrote:... I reduced the size to 50% as a starting step... and before USM application.

I also noticed that the USM actually made the Moire much worse, so I played about with different settings and found that by increasing the threshhold to 10, I could eliminate most of the Moire while still sharpening the straight edges of the buildings.

Can see the difference between the images, I've also noticed that on a few of my images once down-sized into JPEGs etc. Good tips, thanks, I'll try 'em next time I see the same effect.

Cheers.