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E-10 CA

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Mike Tichon

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Here are some ugly photos taken quickly tonight to demonstrate that the E-10, like other cameras, has CA when pictures are taken at full wide with a dark subject against a lighter background. The CA is evident in the 35mm pictures, particularly at the edges. They are in the "work" section:

http://albums.photopoint.com/j/AlbumIndex?u=1330881&a=9898556

I don't know if the CA is a digital phenomena or a lens issue. Probably somebody like Phil would know what causes this. I'd guess it is not simple distortion but the angle the light hits the ccd or something like that.

Mike
 
Mike,

I've been following the various threads on CA and there seems to be a bit of confusion on just what CA is.

The "purple fringeing" is not CA, it's a problem that effects all electronic sensors, like CCDs and CMOS chips. This fringeing is independent of the lens itself and is related to the problem with the sensors responding to the border between the dark and light areas.

Chromatic Aberation is a "rainbow" effect that is lens related, and can effect any type of lens, from cameras, film or digital, to binoculars and telescopes.
You can even see it in eyeglasses, especially the new thin types.

If you have a point or linear light source, CA manifests itself as red and blue "ghosts" on either side of the light source. Most lenses will exhibit a greater degree of CA at wide aperatures.
Kevin
Mike Tichon said:
Here are some ugly photos taken quickly tonight to demonstrate that
the E-10, like other cameras, has CA when pictures are taken at
full wide with a dark subject against a lighter background. The CA
is evident in the 35mm pictures, particularly at the edges. They
are in the "work" section:

http://albums.photopoint.com/j/AlbumIndex?u=1330881&a=9898556

I don't know if the CA is a digital phenomena or a lens issue.
Probably somebody like Phil would know what causes this. I'd guess
it is not simple distortion but the angle the light hits the ccd or
something like that.

Mike
Click to expand...
 
Kevin, based on what you've said, I think the phenomena I created is CA as it is more evident on 35 mm shots, especially at the right and left sides of the pictures. However, there is also purple fringing. Should I be disappointed at the lens quality, esp. after Oly said this was all special, or is the phenomena just in the nature of the digital beast?
Mike
Kevin said:
Mike Tichon said:
Here are some ugly photos taken quickly tonight to demonstrate that
the E-10, like other cameras, has CA when pictures are taken at
full wide with a dark subject against a lighter background. The CA
is evident in the 35mm pictures, particularly at the edges. They
are in the "work" section:

http://albums.photopoint.com/j/AlbumIndex?u=1330881&a=9898556

I don't know if the CA is a digital phenomena or a lens issue.
Probably somebody like Phil would know what causes this. I'd guess
it is not simple distortion but the angle the light hits the ccd or
something like that.

Mike
Click to expand...
Click to expand...
 
Mike,

I downloaded the first tree image and I see mostly the purple fringe problem, even along the left and right edge. Can't really notice a rainbow effect, even at higher than 200% magnification! The best thing to try is night shots, with lots of pinpoint light sources. The rainbow effect will show up better.
Kev
Mike Tichon said:
Kevin said:
Mike Tichon said:
Here are some ugly photos taken quickly tonight to demonstrate that
the E-10, like other cameras, has CA when pictures are taken at
full wide with a dark subject against a lighter background. The CA
is evident in the 35mm pictures, particularly at the edges. They
are in the "work" section:

http://albums.photopoint.com/j/AlbumIndex?u=1330881&a=9898556

I don't know if the CA is a digital phenomena or a lens issue.
Probably somebody like Phil would know what causes this. I'd guess
it is not simple distortion but the angle the light hits the ccd or
something like that.

Mike
Click to expand...
Click to expand...
Click to expand...
 
Not withstanding whether this is true CA or Purple Fringing -- I think the examples are excellent and very, very much better than anything else on the market upto this price point. I actually would compare the first trees shot very favourably with a D30 image I downloaded on the same subject – naturally I lost both it and its link, but from memory the D30 is not any better, at least with the lens sample fitted, that I remember seeing.
Mike Tichon said:
Here are some ugly photos taken quickly tonight to demonstrate that
the E-10, like other cameras, has CA when pictures are taken at
full wide with a dark subject against a lighter background. The CA
is evident in the 35mm pictures, particularly at the edges. They
are in the "work" section:

http://albums.photopoint.com/j/AlbumIndex?u=1330881&a=9898556

I don't know if the CA is a digital phenomena or a lens issue.
Probably somebody like Phil would know what causes this. I'd guess
it is not simple distortion but the angle the light hits the ccd or
something like that.

Mike
Click to expand...
 
Kevin said:
Mike,
I downloaded the first tree image and I see mostly the purple
fringe problem, even along the left and right edge. Can't really
notice a rainbow effect, even at higher than 200% magnification!
Click to expand...
Thanks for the information. So, purple fringing is a digital phenomena, that we will have to learn to work around. I assume that with film cameras there are other types of problems for photographers caused by the nature of the medium. So far, I think I've seen mention of a photoshop plug-in, and also a suggestion for some exposure correction and subsequent gamma correction when shooting pictures that will contain the element of tree branches against a bright sky or other similar situations. Sounds like the stuff a good how-to book could be written about. "Purple Fringing for Dummies"
Mike
 
Mike,
Check out this link on the E-10, it shows the CA effect
http://www.imaging-resource.com/PRODS/E10/E10PICS.HTM
Kev
Mike Tichon said:
Kevin said:
Mike,
I downloaded the first tree image and I see mostly the purple
fringe problem, even along the left and right edge. Can't really
notice a rainbow effect, even at higher than 200% magnification!
Click to expand...
Thanks for the information. So, purple fringing is a digital
phenomena, that we will have to learn to work around. I assume
that with film cameras there are other types of problems for
photographers caused by the nature of the medium. So far, I think
I've seen mention of a photoshop plug-in, and also a suggestion for
some exposure correction and subsequent gamma correction when
shooting pictures that will contain the element of tree branches
against a bright sky or other similar situations. Sounds like the
stuff a good how-to book could be written about. "Purple Fringing
for Dummies"
Mike
Click to expand...
 
Mohit,
I've seen, and downloaded to examine more closely, all your shots.
The night shots are very clean.

CA tends to showup along the edges of the frame, and is most notable at short focal lengths.
My E-10 is on order, hope to get it next week!
Kev
 
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