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Messages - rs

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76
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 13, 2014, 02:24:43 PM »
Did you look at my link to a severe case of moire with a Canon 5D? It is nothing to do with the camera, just an unfortunate case of conflicting frequency.

Yes, I have read your post about the 5D. Interesting. The poster there has many varied images which suffer from the same problem, yet I can't find anything else on the internet about moire and the 5D. Possibly a defective filter? Modified camera? Or a genuine problem which the poster was able to freely reproduce, and I've not found other examples of?

Whichever way you look at it, once baked into the image, moire is a real pain to eliminate. I'd still argue that the effect is to do with the camera - film wouldn't do it after all. A good AA filter should eliminate moire.

Returning back to the 1D, it does definitely have an AA filter:

Quote from: Canon Museum
Low-pass filter   Located in front of the CCD sensor, non-removable

However, it seems like my findings about the weakness of the AA filter aren't alone:

Quote from: DPReview
Moiré

Canon have noted previously that they are using a 'less powerful' (eg. less intrusive) anti-alias filter in front of the sensor. This improves sharpness but does increase the amount of work which has be done by the cameras internal processing algorithms to remove any artifacts created by high frequency detail (moiré patterns). On the whole this appears to work very well, the camera delivers great resolution. But there were occasions (a very small % of my shots) where the right type of detail at the right frequency was able to bypass Canon's trickery and appear in the final image as a moiré pattern.


And, of course the previously mentioned Fred Miranda review. So I guess my experience isn't isolated, so the camera was no doubt operating as it was designed.

To me it seems like you're lucky to have got away without moire, but the weak AA filter combined with poor in-camera jpg processing, and you using raw could be the key to the differences we experienced.

Whichever way you look at it, those 1D images I posted are not examples of images taken without an AA filter. If it was shot without an AA filter, the moire would have been even more pronounced.

77
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 13, 2014, 11:13:12 AM »
I never had an issue with moire.

My experience of that camera is very different to yours.

It is possible that the suit was very unusual, and the worst possible type for (and in every shot, distance from) the sensor. Or perhaps they changed some of the specs during the production run based on feedback? Or, as I have no idea about the history of that camera I borrowed, perhaps it had the AA filter removed?

All I know is every photo my wife took with that camera where there was no signs of camera or subject movement, and groom was in the photo and in focus, was by my standards unacceptable because of the moire.

I did try it myself too, and I struggled. I like to think I'm technically competent, but that camera threw me. We got our hands on the camera about 10 minutes before our work started. In those few minutes, I couldn't figure out how to set the clock to be in sync with the other cameras (in the end, I had to script it in the computer after the event), couldn't figure out how to change it from jpg to raw, and I couldn't figure out how to zoom in on the image to see how it came out. Less than half way through the day the battery died, and my wife and I then just shared the 40D and 5D2 between us. It turns out that was a really lucky.

Reading up about the camera now, it seems like there is no option to zoom the images on the camera's screen. Maybe some of the buttons were dead, which is why I couldn't get around the menu. It is possible that part of the problem with the moire is down to the jpeg processing engine, and if I had raw images to play with, it might have worked out better?

78
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 13, 2014, 10:14:44 AM »
So all of the professionals that used the 1D on fashion shoots, weddings, etc, what do you suppose they did back then?

Without having surveyed 1D users back in the day, I can't answer that.

However, I'd hazard a guess that as the 1D was a 2001 DSLR, this was very much back in the early days of digital photography, when many people preferred film. Digital would have been the sole preserve of techies and pros who need to meet strict deadlines. I'd have thought many pros who used cameras such as this used it alongside a film camera as a workaround for the early digital teething problems.

79
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 13, 2014, 09:43:06 AM »
1D AA filter:

http://www.imaging-resource.com/PRODS/EOS1D2/E1DA5.HTM

Well, if a camera with a weak AA filter gave me those headaches, I'd hate to shoot with an AA filter free camera!

It seems other review sites suspect the filter is present, but weak:

http://www.fredmiranda.com/1D_review/

Quote
Another issue considering mentioning is moiré. These moiré patterns are probably due to the 1D's use of a weaker anti-alias filter in front of the sensor and a larger pixel size.

80
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 13, 2014, 04:02:17 AM »
...
These are all high res crops from a bunch of backyard bird photos I took last year with a 500mm f/4 L II and 1.4x TC. They are a group of the sharpest shots I have of birds in positions where their feathers overlap creating repeated crosshatch patterns (a nightmare for moire). Intriguingly, the overlapping of the birds feathers themselves create moire in analog space, however there is no color or monochrome moire created by the feather crosshatching interacting with the sensor bayer grid.
...

Ok, that's one category that would definitely have been impacted with moire of some kind had there have been no filter. Feel free to show samples from the other categories.

... and I'm not so sure that the first is free of moire.

You didn't even read what I wrote...otherwise you would know where the moire you see (which is actually present in many of those photos) came from, and if you actually understood the cause moire, you would understand that it truly had nothing to do with the sensor. If you aren't even going to read, I'm done obliging you.

Oh excellent! If moire has nothing to do with the sensor then removing the AA filter will have no impact on moire! Thanks for clearing that up.
Moire exists outside of the world of digital cameras. Think of looking through two sets of railing, bird feathers overlapping and so on. If you're there looking at it with your own eyes, the moire is visible. Therefore this particular type of moire is not camera induced.

If a camera somehow distorted reality to change a visual effect which the eye can see, then the camera is doing something wrong. The AA filter is there to stop the camera inducing it's own moire. Any moire which exists in the scene is still preserved. As it should be.

81
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 12, 2014, 12:09:39 PM »
Look, if he can post here and say that the AA Filter has saved the 60,000 images that he's taken with his camera then it should be easy for him to show that, right?

So you're asking him to post a picture without moire? We all shoot with Canon gear, so we've all seen those. The only interest here is where it goes wrong without an AA filter, and the ultimate is a comparison with/without.

I'm asking him to backup his claim that the AA Filter has saved 60,000 of his images with evidence of how from his collection. I don't need to see how others have demonstrated it.

It is a statement which can not be conclusively proven.

Then he should have made such a statement, yes?

So are you denying there's any moire in the shot I posted then?  ??? Is moire just a lie made up by people who don't follow the preaching of Nikon's marketing department?  ::)

82
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 12, 2014, 12:05:17 PM »
Look, if he can post here and say that the AA Filter has saved the 60,000 images that he's taken with his camera then it should be easy for him to show that, right?

So you're asking him to post a picture without moire? We all shoot with Canon gear, so we've all seen those. The only interest here is where it goes wrong without an AA filter, and the ultimate is a comparison with/without.

I'm asking him to backup his claim that the AA Filter has saved 60,000 of his images with evidence of how from his collection. I don't need to see how others have demonstrated it.

It is a statement which can not be conclusively proven.

One can not travel back in time with a modified camera and take the comparison picture.

It's a lot like me claiming that my winter clothing saved me from freezing to death last winter. I believe it to be true and I can not (nor would I) travel back in time to see how I would have fared winter camping in the nude...
If you had a twin, and he was naked and you were wearing winter clothing, we'd be closer to finding out. And we could speculate that third word in my previous sentence would be 'had' rather than 'have'  :o

A Pentax K-3 with its sensor shaking AA filter simulation is a possibility for this sort of test. Anyone here on this Canon forum have one, and is prepared to shoot a wedding with half the shots in the 'ruin the once in a lifetime shot' mode?

83
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 12, 2014, 11:12:00 AM »
Look, if he can post here and say that the AA Filter has saved the 60,000 images that he's taken with his camera then it should be easy for him to show that, right?

So you're asking him to post a picture without moire? We all shoot with Canon gear, so we've all seen those. The only interest here is where it goes wrong without an AA filter, and the ultimate is a comparison with/without.

84
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 12, 2014, 11:09:29 AM »
So for all those that believe the AA filter is necessary, how often have your photographs been saved by it?
...
Here's a real life example. Some time ago I shot a wedding with my wife, and a photographer we know very kindly lent her his old Canon 1D (mk I) to use so I could use two bodies myself. Anyway, after getting back and looking at the images, I learned the hard way just how bad images can look. I don't know the exact hardware specs of that camera, but if it does have an AA filter, it's far too weak. Here is a 100% crop of the grooms suit to give you an idea of the issue that camera has. Try getting rid of that without getting rid of real life detail. I've also reduced it to black and white so you can clearly see the issue isn't purely colour moire. As you can no doubt imagine, the images out of the other cameras were free of this issue. Put all of those photos, and every photo even vaguely along those lines I've taken before and after as being saved by the AA filter.

So every image you took with the 1D Mk I had this moire problem??
Were you using a zoom or fixed focal length lens?
Every in focus shot of the grooms suit exhibited the problem to a varying degree. The lens was a 28-70/2.8L, also borrowed. Every single shot my wife took which was technically good with the groom in the frame was ruined.

Fortunately I took enough shots with the 40D and 5D2 to keep the couple happy, but there were some great shots my wife took which simply couldn't be included in the final selection.

Big learning from that day: don't use equipment for the first time on the day. And don't ever go near a camera without an AA filter. If in doubt, test. If its a new Nikon, stay clear.

85
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 12, 2014, 10:53:15 AM »
I'm not sure what would be an acceptable alternative to you, but I am honestly quite happy to demonstrate the value of an AA filter however possible. In the absence of the necessary equipment to generate usefully comparable results myself, here are as few from DPR:
...

You claim that the AA-Filter has helped you in over 60,000 images and I asked you to post evidence of how that has happened, yet you post an image from DPR.

Now somehow we're supposed to believe that you're an expert on moire and anti-aliasing.

You've made some good long posts here but in the absence of you being able to demonstrate the benefit of the AA Filter with your own photographs, I'm going to call all of your arguments in its favour as being without substance.
Not everyone has hands on access and their own samples from a camera specced by marketing departments. Never the less, jrista was able to post real life examples comparing cameras with and without AA filters. Just because they're not taken by him, does that make the examples null and void?

And what about the image in my post? Is that again null and void because my wife was the one who pressed the shutter button, not me?

I'd go so far as to say that if you wind the clock back to before 2004, the question should be 'Will Canon use an AA Filter in the 1D replacement?'. Go to 2004, and you'll find out the answer is yes. They worked out how to improve the product line. Why go back?

86
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 12, 2014, 04:19:01 AM »
So for all those that believe the AA filter is necessary, how often have your photographs been saved by it?
Some people here are talking about no low pass filter on non-bayer sources, such as x-trans and scanners. Foveon is very similar to a scanner in that it can sample the colour in its entirety at each site, so colour moire shouldn't be an issue. And due to x-trans's random colour filter array (if a 6x6 repeating pattern can be called random?), they've greatly reduced the issue there. However, as jrista has demonstrated, two patterns repeating over each other (a fabric and a sensor) but slightly off can excite false detail - that will remain without an optical low pass filter, and it cannot be corrected in post without major sacrifices. Just think of looking through two lots of wire mesh or railings - you can end up seeing patterns which don't exist in either railing. How can any mathematical calculation get rid of that without destroying detail?

Just imagine if there was a simple optical device with virtually no penalty to the image quality that could be placed in front of the sensor to 100% eliminate noise at all ISO's - who'd argue for not having it, but instead do it all in post? That's the situation we're in with moire.

Here's a real life example. Some time ago I shot a wedding with my wife, and a photographer we know very kindly lent her his old Canon 1D (mk I) to use so I could use two bodies myself. Anyway, after getting back and looking at the images, I learned the hard way just how bad images can look. I don't know the exact hardware specs of that camera, but if it does have an AA filter, it's far too weak. Here is a 100% crop of the grooms suit to give you an idea of the issue that camera has. Try getting rid of that without getting rid of real life detail. I've also reduced it to black and white so you can clearly see the issue isn't purely colour moire. As you can no doubt imagine, the images out of the other cameras were free of this issue. Put all of those photos, and every photo even vaguely along those lines I've taken before and after as being saved by the AA filter.

87
EOS Bodies / Re: Filter redundant due to in-camera processing
« on: January 10, 2014, 06:14:48 AM »
This would tend to suggest that the reason for it being there in the first place (combating moire due to hamming) is not nearly as prevalent or significant as once thought.


No. It suggests that Nikon are removing the moire using in-camera processing.

"the design decision [to remove the AA filter] was made possible by the improved image processsing provided by the new EXPEED 4 image processing circuit."

Read more: Nikon D3300 review: first look | PC Pro blog http://www.pcpro.co.uk/blogs/2014/01/07/nikon-d3300-review-first-look/#ixzz2pzUHHSq7

Quote
Question now has to be, when will Canon stop including it in their designs?


As soon as they can get a chip that removes it effectively without (m)any downsides - removing the filter gives them a free boost in IQ tests.


I don't buy that. Many things can be corrected in post, and moire isn't one of them. pcpro.co.uk aren't renowned for their photographic expertise. In this case I get the impression they just read a couple of marketing gimmicks and wrote it as fact.

88
EOS Bodies / Re: Will Canon ditch the AA Filter?
« on: January 10, 2014, 01:22:07 AM »
Quote
If you're a fashion or wedding photographer then if you're careless...
What, if maybe the bride might be wearing some lace or a veil, or the groom a pinstripe suit? Because that only happens if you're careless?
Exactly!

The photographer should have know that it was going to happen and should have deliberately shot the photos out-of-focus...... :)

LOL! It's very easy to review an image on the back of your camera and adjust the shot if necessary to mitigate moire.
You're sounding like someone that's never shot a wedding :)

The pace is so fast with non-repeatable moments in time that you don't have the opportunity to chimp every shot, and then if needs be, shoot it again after deliberately defocusing the shot to the point that non of the three dimensional object with the pattern is in focus - in other words, not just the eyes slightly out, but all of the happy couples clothes.

For me, personally, I'd rather have a camera which lightly blurs things enough to avoid this issue, leaving me with results which can use the tiniest amount of sharpening to produce images with detail beyond the clients expectations. And focus can be put exactly where the photographer intended.

Yes, you can get slightly more detail without an AA filter, but for many forms of photography the minor advantage is nothing compared to the major disadvantage. Also, some here have argued that if the number of MP are increased to the point where the sensor out resolves most lenses, you can get away without it. My question is, in that case, why do you need no AA filter? If the output is already optically blurred at a pixel level by the lens, no lack of AA filter will sharpen it back up. And then what happens if you buy a new yet-to-be-released super sharp lens in the future and it does out resolve the sensor at certain apertures? Moire, and you being forced to defocus some shots. So why not just keep the AA filter?

Landscape, fair enough - as long as your landscape shots always only contain non repeating patterns. And you never shoot anything with repeating patterns.

89

If the only component of a camera that you place any value on whatsoever is the sensor, then why are you worshiping Nikon? They didn't even make the sensor!

I never said that's the only aspect I value. But, since this is a device that takes images, I think the quality of the image sensor should be placed at the top of the list.

It is a certainly one of the many components that go into making the image. For scenes that don't move and photographers that are happy doing everything manual, it's pretty much all down to the senor and lens. But most people don't buy a camera like the D4 or the 1D X for landscape shots. There are cheaper cameras out there with lessor frame rates, AF and greater MP.

The D4 and the 1D X sacrifice sensor resolution solely to be able to capture the money shots - in other words, the decisive moments in non repeatable situations. Who's going to ask Usain Bolt to re-run the race because the AF was slightly off or the frame rate wasn't quite high enough to capture the moment. I'm not saying the D4 isn't a fantastic tool, or the 1D X is perfection. But I am saying its a better tool for the job than the D4.

A good camera helps the photographer get the money shot. Timing and focus are much more important than DR.

Quote
Just look at any major sporting event - how many more white lenses do you see there than black lenses?

This seems like a very lemming-like way to make decisions.

So you'd say that those working professionals are ill-informed, and your escape from Nikon fanboy land into here is proof that the majority of them are wrong?

90
And if it does or bests Canon, what then?
Does? All of the Nikon FF cameras best Canon *now*.

You're welcome to your own opinion, but that opinion obviously differs from that of the majority of people actually buying Canon and Nikon FF cameras.


If one values dynamic range and cutting edge sensor technology, it's pretty clear who the leader is now.

If the only component of a camera that you place any value on whatsoever is the sensor, then why are you worshiping Nikon? They didn't even make the sensor!

If you can't recover highlights, who cares if you have two extra FPS and built in GPS with Insta-Facebook upload?

And who uses a 1D X for facebook uploads using it's non-existent WiFi and GPS?

Just look at any major sporting event - how many more white lenses do you see there than black lenses?

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