Purple Fringe on FZ Leica lenses.

[pacman]

Hi, has anyone noticed how bad are these lenses when it comes to that annoying purple finging thingy?

It is more noticeable in the edges of the picture when there's bright against dark objects (let's say the front grid of a car under the sun light) there are purple lines in one side, and sometimes in the opposite side, greenish lines.

I know that's due to physics laws in aspherical lenses that light divides into its spectrum the more it reaches the edges of it, but I guess the leica lenses panasonic uses on its cameras is worse at it than the carl zeiss of sony.

I also think the barrel distortion is very noticeable, does it work for you increasing the focal length to get rid of it a little?

What do you think about it, how do you manage those annoying problems?

[Anex]

need examples, it's most likely how you're shooting but without examples, it would be a little difficult for us to correct/provide info. I can say I've not had ANY purple fringing, nor any distortion...and you could probably count on one hand how many people have posted about it in here..not a common thing at all.

Anyways, post some examples and some very qualified people will be able to help you...

[timmciglobal]

I've noticed quite some CA on zeiss products for sony, with the single exception of the R1 which gains the benefit of glass size.

Tim

[astro]

CA can be easily reduced by stopping down the aperture. CA is generally produced by apertures larger than F/8 on refracting lenses.
Costly Extra-Low Dispersion glass can also reduce or pretty much remove all CA. The FZ30/20/15 only uses one layer of such glass. Not much reduction can be seen though, with such a small amount of glass that is ED. This can be seen when comparing the ED version with the non ED version(FZ5/4/3). The CA on the FZ5 isn't much worse than the ED counterparts.

[genece]

Astro's solution is correct too large an aperture causes that, as does poor focus which happens at the edge of a photo.
That said the FZ cameras are the best of the Ultrazooms for very little fringing
and its not fair to compare with a camera that is a lesser zoom.
Everything is a compramise and thats one you must pay with an ultrazoom .
Check the canon S2 IS if you want fringing.

Image from Imaging Rresource from a canon S2 IS
Its one of the photos from their comparometer you can look at the FZ5 and 20 photo there also.
You can put the FZ photos against any ultrazoom you want ..then tell me whats bad.

http://69.93.231.164/PRODS/S2IS/FULLRES/S2ISHOUSEWBM.JPG

[Medic1210]

Gene, you can't really use that image as an example of CA or purple fringing. The reason is because it is a photo of a poster. The actual image wasn't taken by that camera. That site mentions this fact IIRC, and you can see some horizontal irregularities above the house and in the trees that almost look like tape or reflections on glass.

Mike

[pacman]

This is what I mean: I took this pic with my FZ10 (resized to fit this).

http://static.flickr.com/31/48932664_0a341c5f68_o.jpg

Notice the fly is located in the left downside corner of the three thirds imaginary lines some photographers use, and I get that purple/greenish fringing I was talking about, here's the crop:

http://static.flickr.com/28/48932666_140dfa797d_o.jpg

I assume that chromatic phenomenon is inscreased when the object in concern is located close to the edge of the aspherical lens... I assume that cause if I took the same fly in the middle of the field I don't get the fringing.

[TheObiJuan]

It's there and can't be helped. 99% of digicams suffer from it too.
It is hardly noticeable even at 8x10 prints.

[genece]

Medic
You did not read that correctly that is a downloaded original picture, and they use the same house in all their tests ... Thats just the way the Canon is.


And the FZ10 was much worse at the fringing than the rest of the fluzzis with the Venus 2 processor. But poor focus still has a lot to do with that Fly photo.

Gene, you can't really use that image as an example of CA or purple fringing. The reason is because it is a photo of a poster. The actual image wasn't taken by that camera. That site mentions this fact IIRC, and you can see some horizontal irregularities above the house and in the trees that almost look like tape or reflections on glass.

Mike

[StanStan]

I take bugs too. I usually put the bug in the center of the image with as good lighting as I can get and as close as possible. I don't use the rule of thirds unless there are interesting features in the rest of the picture. I shot light houses recently and did put the light house in the upper right or left as there were other interesting objects: boats, trees, islands, and water in the background. For the fly there is nothing interesting in the background, the fly is too small,
could use better lighting. I would have used spot focus and bracketed the exposure.

IMHO

Stan

[pacman]

I know it all already, it's not an artistical advice post, i did a technical question about a physics phenomenon in the lenses. I located the fly near the corner to show you that there the purple fringing is higher than in the center.

And I don't think it has much to do with focus or bracketing, even so I get that horrible purple thing that makes the pictures look like if they were taken with a cheap "point and shoot" cam.

[genece]

You will not solve the problem if you do not believe the cause.
It is aperture and focus plus High zoom. Poor glass can be a cause but not with the Leica lens.

[Anex]

nothing really to add for me, gene and stan pretty much said it; lighting and focus...both of which in your photo appear quite off. Remember, lighting has a profound effect on things so when you combine poor lighting with questionable focus, you'll almost always get a bad photo (bad exposure, purple fringing, distorted image, etc.).

[pacman]

Poor lighting? check this out, there's plenty of light and it gets even worse than the previous image, and i think the focusing is quite good.

First off, the full frame pic:

http://static.flickr.com/24/49415249_f159a1ecd5_o.jpg

Now, this is the upper left corner of the frame (cropped and resized to show more detail) notice that horrible greenish and purple edges even with plenty of light.

http://static.flickr.com/26/49415251_aca36f2ca4_o.jpg

And now, a middle crop of the frame, there's not purple fringing there!

http://static.flickr.com/28/49415250_0eb27cb832_o.jpg


so.. any advice to lessen that?

[genece]

That picture is pretty well focused , Focus magic says its one pixel off in the left half of the photo. And as was said the FZ10 was the worst of the FZ cameras as far as the fringing.
But the lighting is sure not correct in that photo , you are finding the fringing
where the building meets the blown sky.
No camera can do it all , you have to help.
The edges of all lenses are softer than the center, thats the way they are made. The FZs get a good grade as far as that softness compared to most cameras.
But really if you need to look that hard to find a problem,the old FZ10 is OK.
I like mine.but in my eyes the FZ20 is better and the FZ30 is better yet. This photo taken with a 717 see any there?

[coldrain]

You will not solve the problem if you do not believe the cause.
It is aperture and focus plus High zoom. Poor glass can be a cause but not with the Leica lens.
For some reason people give magical meaning to the name Leica on the lens of a Panasonic. But the CA you see is caused by the lens.
CA has to do with different wavelenghts traveling through the lens system in different ways, and it is hard to make a lens, especially with a big zoom range, to act perfectly. So certain wavelenghts travel in some parts of the lens differently tham other wavelenghts, and they end up "in the wrong place".

You can see that in purple with high contrasts or with very bright lights, the well known purple fringing. Or sometimes you see around any edge in a picture red or green shadows. Then the red or green give CA.

Also in Leica lenses of Panasonic. Leica is a famous camera and lens builder. Some of their lenses have legendary status. But those also cost very very much. Panasonic cameras with the Venus II processor get more CA out of pictures via that processor, this is why for instance the FZ20 is better in that respect than the earlier models.

Other camera makes and models often display some CA in one way or another too. Some cameras have better lenses than others and seem to be relativily CA free. But CA has very little to do with focus or lighting, you can improve things by using a smaller aperture. The smaller aperture lets light travel through the lens in a different way, lenses are most of the times worst in their extremes, so the lowest and highest aperture best are avoided for this kind of problem, and CA often is worst in the widest angle of the lens (and lenses often are softest (unsharp) in their longest setting).

[Medic1210]

Medic
You did not read that correctly that is a downloaded original picture, and they use the same house in all their tests ... Thats just the way the Canon is.

Gene, I'm quoting this from www.imaging-resource.com It is on every camera review's Test Image page. It is listed under the house shot you showed where they re-shoot the house from a distance in their Far-Field Test. Here is the quote in reference to the image you posted.

"This image is shot at infinity to test far-field lens performance. NOTE that this image cannot be directly compared to the other "house" shot, which is a poster, shot in the studio. The rendering of detail in the poster will be very different than in this shot, and color values (and even the presence or absence of leaves on the trees!) will vary in this subject as the seasons progress."

It says this same thing under every camera's Far-Field test where all cameras get a chance at shooting that same house and house poster. Since the image you posted is an image of a poster that was shot in the studio, it cannot be used to show CA. To show CA, you need to post the Far-Field test shot that was actually taken with the camera.

Mike

[genece]

I was trying to say something like that ....but I will stick by poor focus adds to the fringing at least most shots I have taken with the fringing, are not in perfect focus.

And I do not believe the Panasonic lens are magical but I do believe they are better than any in the price range. And some ina higher range.

I quit!



.

[Medic1210]

Poor lighting? check this out, there's plenty of light and it gets even worse than the previous image, and i think the focusing is quite good.


Now, this is the upper left corner of the frame (cropped and resized to show more detail) notice that horrible greenish and purple edges even with plenty of light.

http://static.flickr.com/26/49415251_aca36f2ca4_o.jpg


so.. any advice to lessen that?

This is a problem in high contrast areas like you show. It's a problem inherent in small sensor digicams. If you find a better cam that doesn't show it, then buy that cam. Here is a quick fix of the CA done in Jasc PSP 9. Less than 1 minute fix.

http://img.photobucket.com/albums/v335/Medic1210/49415251_aca36f2ca4_o.jpg

[road_rascal]

Poor lighting? check this out, there's plenty of light and it gets even worse than the previous image, and i think the focusing is quite good.

Now, this is the upper left corner of the frame (cropped and resized to show more detail) notice that horrible greenish and purple edges even with plenty of light.

http://static.flickr.com/26/49415251_aca36f2ca4_o.jpg

so.. any advice to lessen that?

First of all, even printed at 8x10, that's going to be a nice picture. Secondly, just how many are going to zoom in 500% on a photo to prove there's a problem with the photo? Sure, I post process every photo I intend to print, but let's not get that picky :rolleyes: .

[John_Reed]

At the edges, as Gene & others said. It's really not "purple," I think, more like "blue," wouldn't you say? It reminded me of this shot I took back in 2003 with my then-new FZ1 down in Aruba:
http://newton-i.usefilm.com/5/5/7/557/142779-large.jpg
Those bluish branches in the back are showing the same color of "fringing," I think, as the blue edge you pointed out in your example.
It's still present in this FZ10 photo of a Cowbird (?):
http://John-Reed.smugmug.com/photos/11760977-M.jpg
And by golly, it's still here with the FZ30:
http://John-Reed.smugmug.com/photos/38759712-M.jpg
I looked through a lot of my old photos to find these scarce examples. Blue fringing seems to pop up when the sky is blown-out behind the foreground objects which are in focus. Here's an FZ15 shot of a Bushtit, for example, where there's no bright sky behind, and also no fringing:
http://John-Reed.smugmug.com/photos/14164572-M.jpg
Perhaps an alternative viewpoint?

[LoveLife]

You can reduce the occurrence of fringing or CA by making sure the focus is sharp and the aperture is F5 or higher.

[pacman]

Well john, the fringing phenomenon occurs when there are bright pixels next to dark pixels, so a dark object agains a shiny sky will produce the fringing... and it trends to happen more the closer it is to the edges of the picture; the last pic you posted doesn't have any of those variables.

Hehehe and yes, I sometimes get so picky at this point, I love when my pics look crisp and flawless even at a 500% amplification, most of the time when I got a little amount of noise I end up applying nose reduction things and using the cloning tool to remove the fringing; I'm virgo, go figure, I love perfection. :D

And thanks for the advice, I will try using smaller apertures. I know the fringing will always come up, it's physics laws, but I'll try to make it less noticeable.