Initial E-420 and DZ 25mm pancake samples

[Bob Ross]

Hi Ian,
I downloaded the JPEGs of the "Misses Bridges" and "Paper Mill" shots and took a long look at them. I am getting surprised at the amount of green fringing that I am seeing in yours and others samples. This is hardly what I'd expect from an Oly prime lens. Others have commented on seeing it along the edges, but I am seeing it across the images. The boat name "Misses Bridges" against the white background is one place to look, even if you have to go to 200% and on the paper mill shot it shows along the roof and chimney lines against the sky, towards the side of the picture it is on. It does correct with the CA tool in PWP. The image clarified after using the tool.
I'll be interested in what you find in your clinical tests. Chromatic Aberation is the inability of a lens to bring light of different colors to the same point of focus. It reduces with smaller apertures. Lateral Chromatic Aberration is the inability of a lens to maintain the same image size for different colors. The aperture size doesn't affect it. The first shots that I saw were wide open, but yours were closed down, so I would guess that it is Lateral Chromatic Aberration. Since your clinical tests are probably with high contrast targets, it should show up and at all apertures, if my guess it right. With digital it could also be some processing problem, but if it doesn't show with other lenses, it probably isn't. Using/testing the lens on another Oly body (E-510?)might add some info. I look forward to see what you find.
Bob Ross

[Ian]

Originally Posted by Bob Ross

Hi Ian,
I downloaded the JPEGs of the "Misses Bridges" and "Paper Mill" shots and took a long look at them. I am getting surprised at the amount of green fringing that I am seeing in yours and others samples. This is hardly what I'd expect from an Oly prime lens. Others have commented on seeing it along the edges, but I am seeing it across the images. The boat name "Misses Bridges" against the white background is one place to look, even if you have to go to 200% and on the paper mill shot it shows along the roof and chimney lines against the sky, towards the side of the picture it is on. It does correct with the CA tool in PWP. The image clarified after using the tool.
I'll be interested in what you find in your clinical tests. Chromatic Aberation is the inability of a lens to bring light of different colors to the same point of focus. It reduces with smaller apertures. Lateral Chromatic Aberration is the inability of a lens to maintain the same image size for different colors. The aperture size doesn't affect it. The first shots that I saw were wide open, but yours were closed down, so I would guess that it is Lateral Chromatic Aberration. Since your clinical tests are probably with high contrast targets, it should show up and at all apertures, if my guess it right. With digital it could also be some processing problem, but if it doesn't show with other lenses, it probably isn't. Using/testing the lens on another Oly body (E-510?)might add some info. I look forward to see what you find.
Bob Ross

I'm seeing what you are seeing, Bob, and at smaller apertures too. I will be querying this with Olympus in case my lens is faulty. I will also be looking at the performance of this lens on the E-3 in case it's a sensor/image processing issue as well.

Ian

PS Been playing in Studio 2.1.2 with the RAW files and there is a fair deal of correction at one's disposal (Aberration Comp). I'm using -11 R/C and +56 B/Y.

[alert_bri]

Hi Ian,

could you please comment on the live view implementation? is it possible to lock the mirror up and take multiple shots without the mirror flapping?

Kind Regards

Brian

[LAWHAMPTONS]

I am going to look at the E420 on Wednesday in NY. Have you figured out what was causing the CA or should I hold off buying? Thanks. Steve. lawhamptons

[Bob Ross]

Originally Posted by LAWHAMPTONS

I am going to look at the E420 on Wednesday in NY. Have you figured out what was causing the CA or should I hold off buying? Thanks. Steve. lawhamptons

Hi Steve
The CA is an issue with the 25/2.8 and not the kit zoom lens. The CA seems to show up differently in the various sets of samples from the 25/2.8 and some are very minimal.
I'm not sure that the E-420 + 25/2.8 kit is available yet, though reviewers are getting them.
The 25/2.8 Pancake is a basic lens with no aspheric or ED elements and the MTF curves show some possible problems. The CA may be design inherent or assembly misalignment (QC). A design quirk might be fixed in firmware, but asembly variations need a repair fix.
The only problems that I have read about are the CA with the 25/2.8 and some banding at ISO 1600. The little kit zoom is getting compliments.
Bob

[LAWHAMPTONS]

Hi Bob. Thanks for your input. I am going to "feel" the camera on Monday and will probably buy it with the zoom lens kit because of its size and weight as a DLSR, and the good results I have seen on this site. Steve

[carder21]

Hi bob I dont mean to be picky but you menstion the 25mm pancake lens as having no ED or aspheric elements, with the first one you were right there is no ED elements in this lens but the lens does have a molded asperical lens.
SO THERE GET YOUR FACTS RIGHT.


PS ONLY JOKING

[Bob Ross]

Originally Posted by carder21

Hi bob I dont mean to be picky but you menstion the 25mm pancake lens as having no ED or aspheric elements, with the first one you were right there is no ED elements in this lens but the lens does have a molded asperical lens.
SO THERE GET YOUR FACTS RIGHT.


PS ONLY JOKING

Right you are. They snuk that puppy in at the back end, probably as an after thought for marketing......