M9 & Moire

[sanyasi]

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Alan G's fine photo makes me want my M9 more than ever so I too can make beautiful pictures.

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[250swb]

I'd love to see the original .dng file but the photo in the first post seems massively overprocessed to judge anything by.

 

Steve

[m8point2]

Moire? What moire?:p

 

Less is moire, or was it the other way around?

 

el

[AlanG]

Alan G's fine photo makes me want my M9 more than ever so I too can make beautiful pictures.

 

Haha... You shouldn't have written that as it encouraged me to make a variation where Ken Kesey spiked the church's holiday punch....

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[Verbatim666]

Thanks for the tips from those who have posted them.

 

To answer some of the points raised.

 

Why use flash? Well, I could also ask, why didn't I use my 1DS3? Why didn't I take them with the subjects in profile? Why didn't i make it monochrome? Why have the christmas tree in the background? All quite valid questions and the only answer is that (given the constraints I had) this is how I wished to take the picture. clearly a bad decision in this case.

 

The magenta cast of the shirt? I agree it is probably infrared induced.

 

I agree that changing the white balance changes the colours (is that a surprise?). I don't think it gets rid of the moire at all though. I took 25 couples using the same setup and the white balance was set by asking a couple of the subjects to hold an x-rite colorchecker (not this couple though) and taking the white balance off that. I understand from 'the rev' that his dog colour was cut from the packaging of a christmas present, serve me right for buying a colorchecker if a christmas wrapper is more accurate for WB!

 

With regard to the processing of the DNG, there is absolutely no fiddling at all. With the exception of the WB, it is just as it comes out of lightroom on its presets. clearly lightroom does something to make a low res jpg, but again I just went with the presets.

 

I did not make it clear in my original post that no processing at all was done on the image presented though. I may even have led some to believe that there had been lots because i mentioned the things i had tried to get rid of the moire - but thankfully lightroom is non destructive, so i posted the original conversion! So sorry if I wasn't clear.

 

The colours are pretty garish, but to be honest I don't think that is the point. I know how to fiddle with the image to change those. The question was about Moire as I don't know how to get rid of that. Changing the colours of the image changes the colours of the moire, but doesn't remove it in any way. I think the posts by others confirm that quite clearly. Perhaps I presumed too much though, I didn't know until I fiddled that changing the colours just changed the colours and I had therefore dismissed that as irrelevant.

 

When I got the M8 about 2 1/2 years ago, the very first photo I took was of my wife. Her black coat was instantly purple on the screen and we were in hysterics. This incredibly expensive camera changing the colour of a coat so obviously and that this effect had taken such a while to be recognised as an issue - people even disputing that it occurred! The filters were a good solution for me and it was not an issue as far as I was concerned once I had them (and the firmware of course).

 

In those 2 1/2 years to the best of my knowledge I never had an issue with moire with the M8- or with my other cameras. I have now had the M9 for about 10 days (it came on Christmas eve) and have found an issue with moire. It is only on this shirt at this time. I took 4 photos of this couple and it is on all of them, but it is not any others. So it is clearly not common, but perhaps it is not ridiculously rare as well. We don't know, it is a new camera with not many in circulation yet.

 

As yet, I have not found a postprocessing software fix that has been helpful. Perhaps I will have to hope that leica come up with a fix (vaseline on the front element?), or perhaps I will never see it happen again. Perhaps I am just fussier than many, but to me it is disappointing and looks aweful in this image.

 

I am aware of (some of) the compromises that have to be made in camera design and why this occurs in a leica. I do not understand it though as it isn't my area and have no idea if the laws of physics, optics and digital design are such that this is impossible to fix at any point in the chain without an AA filter like others use, or whether there is a totally effective fix (like the IR filters) that hasn't been done yet. AlanG's work is clearly a great improvement on my original, but alas, I feel the shirt still has some wavy lines and this probably isn't the definitive solution.

 

Unfortunately to me this shot as yet cannot see the light of day, apart from on this forum, as it isn't something I would wish others to see. This takes me back to one of the comments I made at the begining- I took the shot as I wanted to and this has resulted in an unusable picture, because of one of the design characteristics of the M9. It is hardly the end of the world, but neither is it something I can be happy about. I don't see myself mounting an A2 print and saying to others 'look at this moire isn't it great! This is why I bought a leica, you just wouldn't have got that effect with a canikon.' It is just a shame that occasionaly if I take a shot how I want to, the camera says no.

[Artichoke]

the photographer has to know his equipment

I was not at all surprised that the M9 shows more moire than the M8

I have found this the case as well with my M9

a weak AA filter & high resolution lenses/sensors is a recipe for moire

it is not all that great a problem to fix in post

there are many plugins that can help you with this & they all work better when applied to only the problematic portions of the photograph

having heard folks using canikon DSLRs modifying the AA filters in their cameras, I am convinced it is better to deal with moire infrequently than have softness inherent to an AA filter introduced into every image taken

[AlanG]

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AlanG's work is clearly a great improvement on my original, but alas, I feel the shirt still has some wavy lines and this probably isn't the definitive solution.

 

I just posted the image as a joke because my initial reaction was that nobody would have cared about the moire in that photo... with that wig and all. With digital cameras, moire is just a fact of life. I get it occasionally on a Canon 5DII, probably not as often or severely as on cameras that don't have an AA filter. I really do not think that AA filters degrade sharpness as much as some people think - there are plenty of very sharp images made with cameras that have AA filters.

 

For this shirt image, I masked the shirt, desaturated it and darkened it, then I used a paint brush to even out the shades a bit. I did a real quick rough job. It certainly could be better if I was working on a larger file and took my time. But how many people are going to scrutinize this photo? The few times I played with the moire filter in C1 Pro it did a pretty good job. But I'd have to have your raw file to see what it could do with it.

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[george_b]

Moire? What moire?:p

 

You should go to SpecSavers.

[lct]

One can hardly ask for a Bayer sensor w/o AA filter and complain about moiré in the same time folks. Only alternatives are shooting jpegs with a DMR, using a noisy Foveon sensor, choosing an MF camera with removable AA filter, negating the obvious ("what's moiré?", "never got moiré", and so on) or simply accepting the filter and sharpening a bit in PP like LCT and a million vulgar nikanopus photographers.

[borowiec]

I have moiré problems quite often as I frequently photograph architectural and industrial subjects that feature a lot of repetitive detail. It seems to be a bigger problem with the M9 than it was with the M8. After trying every solution out there, this is what works the best for me (I believe this came off a post on Photo.net, probably from the incomparable Patrick Lavoie):

 

1. Duplicate the background.

2. Apply a strong Gaussian blur, one where you still see some silhouette but barely, in the range of 15-30 pixels (I use 27).

3. Add a small amount of the Noise filter on top of the newly blurred image, around 3-5% (I use 4%), Gaussian, Monochromatic.

4. Change the blending mode of this layer from Normal to Color.

5. Create a mask, fill with black.

6. Use a brush with white paint to remove the moiré.

 

I wrote a Photoshop action for everything but the last step which, obviously, you have to do by hand.

 

I haven't tried the Fred Miranda plug-in mentioned above but I will check it out, and I don't have the Pro version of C1 so I haven't used their moiré tool either. However, the above technique has worked well in every instance that I've encountered so far.

 

Andrew Borowiec

[haroldp]

Use (or not) of an AA filter is a design decision that is a two edged sword in either case.

 

While I personally prefer Leica's approach of maximizing resolution and dealing with occasional ( in my case extremely rare ) artifacts (moire is only one posibility), it is unrealistic to want the positive side of the trade-off and not expect once in a while to have to deal with the other.

 

If one believes that the AA filter serves no useful purpose, then the obvious conclusion is that Nikon / Canon engineers have not simply chosen a different set of trade-offs, but are incompetent. The overwhelming evidence is that this is not the case.

 

While there certainly are many experienced and talented Nikon / Canon users, Leica 'M' users are on average more experienced, and understand these trade-offs and tolerate them.

 

Nikon / Canon being mass-market brands would not want their support infrastructure overwhelmed by outraged customers, and so chose a path that sacrifices a very small amount of IQ (after proper PP) in exchange for fewer problems. In light of their market position, this is a very rational choice, as is Leica's in their market.

 

I for one, am very happy to have choices available to me as a customer.

 

Ultimately this problem will disappear as practical sensor resolution goes up, or beyer sensors are replaced with discrete pixel devices, since artifacts are generally a result of lenses outresolving bayer sensors.

 

One benefit of more (read smaller) pixels in a given sensor size is that AA filters can become less agressive. When the sensor significantly outresolves the lens, then the lens is the AA filter. That is why pocket cams have no AA filter, the combo of 2.5 micron photosites and cheap lenses.

 

One of the reasons that my 24mp ( app. 5.6 micron photosites ) Nikon D3X produces noticably sharper images than my 12 mp ( app. 8.2 micron photosites ) D3 / 700's, even on screen and in small prints, is that Nikon engineers coupled the D3X with a much less aggresive AA filter.

 

Of course, the other side of this particular trade-off is that above ISO 800, the D3 starts to look better ( to my eyes ), and is of course faster.

 

Horses for courses.

 

Sorry for the rant, I tried to stop myself but could'nt

 

Regards ... Harold

[lct]

No wonder why he's using IR-cut Leica glasses.

 

[AlanG]

...While there certainly are many experienced and talented Nikon / Canon users, Leica 'M' users are on average more experienced, and understand these trade-offs and tolerate them.

 

 

This seems like quite an assumption. What do you mean by average - are you counting beginners and novices who just happen to buy a Canon or Nikon and don't know or care about much? I'd suspect there are quite a few more top pros using digital Canons and Nikons than are using digital Leicas.

 

Consider that the original poster was surprised to get moire in this photo and doesn't know how to eliminate it. I don't see how you could become experienced with the moire trade-off you get from not having an AA filter until you buy a camera that doesn't have one and then perhaps decide you don't like getting moire so often.

 

Replacing speculation about AA filters regarding moire vs.sharpness with actual tests and facts would probably be enlightening to even those "more experienced" Leica users.

[haroldp]

This seems like quite an assumption. What do you mean by average - are you counting beginners and novices who just happen to buy a Canon or Nikon and don't know or care about much? I'd suspect there are quite a few more top pros using digital Canons and Nikons than are using digital Leicas.

 

Consider that the original poster was surprised to get moire in this photo and doesn't know how to eliminate it. I don't see how you could become experienced with the moire trade-off you get from not having an AA filter until you buy a camera that doesn't have one and then perhaps decide you don't like getting moire so often.

 

Replacing speculation about AA filters regarding moire vs.sharpness with actual tests and facts would probably be enlightening to even those "more experienced" Leica users.

 

Alan:

 

You are correct, I have no evidence whatsoever. This was indeed a wild assumption based on the probabilities of large numbers.

 

There is no doubt that many more top pro's ( and amateurs ) use Nikon or Canon than use Leica. I use Nikon more frequently than Leica simply because the circumstances that favor Nikon use come up more frequently for me, than those that favor Leica ( for me ). Neither is better than the other, they are optimized for different circumstances.

 

It appears to the casual observer (me), that an even higher proportion of beginners or casual shooters looking for a step up in quality from digicams ( which mostly do not use AA filters ) will get a Nikon or Canon DSLR, than a Leica M8 (or 9).

 

You are again correct, I am "counting beginners and novices who just happen to buy a Canon or Nikon and don't know or care about much", because these are the people who would storm their respective technical support organizations castles with torches and pitchforks if they saw a hint of moire or stairstepping or any other nasties.

 

While there are certainly some converts, a casual scan of this forum tells me that a very significant fraction of M8 / M9 users were at some point users of film RF cameras, ( I also have and use an M2 and an M6 ).

 

It is also clear that this group prizes the qualities of Leica RF enough to be willing to tolerate a level of equipment odd, and misbehavior that most Nikon / Canon users would not.

 

Neither would the Nikon or Canon corporate or tech support organizations ( don't even think about marketing ) tolerate this for long.

 

My own DSLR (or SLR) experience is with Nikon, I am making also making the wild assumption that the Equipment, Corporate, And User profiles between Nikon and Canon are similar enough that similar behaviors will likely result.

 

My main point, was and is that IMHO, not using an AA filter is rational design choice for Leica in it's situation, and that using an AA filter is an equally rational design choice for Nikon / Canon in their respective situations.

 

In this new year, I will seriously consider switching to decaf.

 

Regards and happy new year ... Harold

[AlanG]

I wasn't trying to paint you negatively, just trying to stay to the point about moire. All things being equal, which they aren't in this case, I think you have to shoot a lot with a camera that has no AA filter before you can decide if the moire is bad enough for you to prefer the same camera with an AA filter. People buy digital M Leicas for many reasons other than the inclusion or absence of an AA filter and what that will entail. Since buying an M9 with an AA filter on the sensor is not an option, it is hard to know what experienced and educated users would choose if given a choice.

 

Well it figures that if you are spending $10,000 or so for a body and lens, you are either a pro or a serious enthusiast, might have done a bit more research, and can justify your reasons better than someone who spends only $1000 or so. Whether the camera is a Leica M9 or a Nikon D3x.

[tgray]

Moire sucks. Margulis's LAB photoshop book has a section on removing it. It might help. If I recall, it was similar to this link:

moire removal.

 

The idea is that moire is present in the L channels AND the a and b channels. By a combination of luck and skill, you can use the pattern present in the a/b channels to knock out (some of) the pattern in the L channel. Then simply blur the pattern in the a/b channels.

 

Basically:

1 - convert to lab

2 - select the shirt

3 - go to the b channel, where the color moire is the worst

4 - duplicate that to a new layer, masking out everything but the shirt (with your selection)

5 - invert it, set to hard light (or some other mode that works better) and change opacity until you like the result. This will help reduce the moire in the L channel where there was moire in the color channels.

6 - flatten image

7 - use the shirt selection to apply a blur to the a and b channels to remove the color moire

 

In this example, there was still some moire left over in the L channel which wasn't present in the original's a and b channels. So I used the selection and ran a smart blur filter on it and tweaked it until it looked a bit better. You could have probably done that from the start too.

[haroldp]

I wasn't trying to paint you negatively, just trying to stay to the point about moire. All things being equal, which they aren't in this case, I think you have to shoot a lot with a camera that has no AA filter before you can decide if the moire is bad enough for you to prefer the same camera with an AA filter. People buy digital M Leicas for many reasons other than the inclusion or absence of an AA filter and what that will entail. Since buying an M9 with an AA filter on the sensor is not an option, it is hard to know what experienced and educated users would choose if given a choice.

 

Well it figures that if you are spending $10,000 or so for a body and lens, you are either a pro or a serious enthusiast, might have done a bit more research, and can justify your reasons better than someone who spends only $1000 or so. Whether the camera is a Leica M9 or a Nikon D3x.

 

Alan:

 

I know that you did not intend offense and I did not take any.

 

I agree with everything you said in this post. It is the other Leica qualities that we prize that incline us to tolerate it's idiosyncrasies.

 

It is good that aliasing artifacts are rare, particularly with pixel pitches at or below 6 microns. Experience also helps us anticipate the conditions in which we might get them such as regular fine geometric detail (fabrics or architecture) in strong light.

 

As a primarily Landscape and Wildlife photographer, it is almost never an issue for me.

 

When I shoot the occasional wedding ( As a favor, I am no longer a professional ), I never (well almost never ) use direct flash. Bounce flash ( ceiling or umbrella ) or indoor available light rarely yield artifacts. For weddings, I am more likely to take a Nikon anyway because of it's much stronger support for multiple lights.

 

This thread is a good argument for shooting Raw, because future raw processing software is likely to do a better job of artifact removal and we can then re-visit problem shots.

 

Regards .. Harold

[Verbatim666]

I am glad I posted this picture.

 

I have enjoyed the 'modifications' done by others and am very grateful for the tips.

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