used lens purple fringe ?

kiwao · 03-03-2010, 07:17 PM

Just bought used 35mm-105mm A lens. Test shots reveal purple fringing I think? Never seen it this color before. Any comments would be much appreciated

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**dadipentak** · 03-03-2010, 08:17 PM

Yeah, that's to be expected in high contrast areas like that. It's not all that difficult to deal with in PP--desaturate and darken it. That's one of my favorite lenses, btw.

stevebrot · 03-03-2010, 08:27 PM

That is mostly flare with some CA thrown in for spice.

Steve

JeffJS · 03-03-2010, 08:36 PM

Do you have a filter on the lens? Are you shooting wide open?

kiwao · 03-03-2010, 09:08 PM

Quote:

Do you have a filter on the lens? Are you shooting wide open?

I do not have filter. Shooting wide open. The lens is in good condition just some dust but I was worried that somebody had cleaned the front element so much that they had removed the coating.

Can't decide if I should return it. Yesterday I spent the afternoon wandering around snapping anything in view just to try it out and found my handheld technique wanting

!
Also when zooming it moved out of focus slightly.

JeffJS · 03-03-2010, 10:10 PM

Originally posted by kiwao

I do not have filter. Shooting wide open. The lens is in good condition just some dust but I was worried that somebody had cleaned the front element so much that they had removed the coating.

Can't decide if I should return it. Yesterday I spent the afternoon wandering around snapping anything in view just to try it out and found my handheld technique wanting

!
Also when zooming it moved out of focus slightly.

I have to zoom very carefully for mine to stay in focus throughout but it does. As for the CA, I think it's as much a product of condition and setting than anything else. This one was done wide open.. Different conditions because I actually had a blue sky for the shot. I think though that if the sky were white, CA abound in the OOF trees. Couldn't tell you the actual focal length. Had the camera set to 100mm and left it there.

The reason I asked about a filter is because your shots look a little foggy to me. A type of glow around the CA areas. Usually when I see CA or color fringing, it's a more well defined outline.

sterretje · 03-03-2010, 10:11 PM

I agree with dadipentak.

First advice is usually to use a narrower aperture. I also noticed (during recent tests with an FA31 on a K10D):

Correct exposure on the contrasty area is very important; my testshots were pink flowers on green leafes; using matrix metering or centerweight in this scene did not do it and spot metering improved the results a bit (at least the flowers started to turn out pink instead of white). Your scene is the opposite and I think that underexposing will improve the situation.
The standard JPEG settings of the camera worsen the purple fringing (raw format hardly shows the fringing); this was an absolute eye opener for me; point 1 above was still with standard JPEG settings

Due to point 2, I have now set the jpeg engine's parameters in the camera to neutral as I want them to reflect the raw image. Not sure if I will keep it like that but for now it is.

kiwao · 03-04-2010, 08:14 PM

Thanks for the comments everyone.

Quote:

The reason I asked about a filter is because your shots look a little foggy to me. A type of glow around the CA areas. Usually when I see CA or color fringing, it's a more well defined outline.

I think stevebrot was correct with

Quote:

That is mostly flare with some CA thrown in for spice.

This probably accounts for the fogginess.

Is there anywhere I can get a hood?

More shoot anything in view test shots attached. I think they are ok. All wide open. The steel ball is 100% crop.

One more thing. Can the pop up flash be used with this lens?

03-03-2010, 09:08 PM	#5
kiwao Forum Member Join Date: Jul 2008 Location: tokyo Posts: 83 Original Poster	Quote: Do you have a filter on the lens? Are you shooting wide open? I do not have filter. Shooting wide open. The lens is in good condition just some dust but I was worried that somebody had cleaned the front element so much that they had removed the coating. Can't decide if I should return it. Yesterday I spent the afternoon wandering around snapping anything in view just to try it out and found my handheld technique wanting! Also when zooming it moved out of focus slightly.

03-03-2010, 10:10 PM	#6
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	Originally posted by kiwao I do not have filter. Shooting wide open. The lens is in good condition just some dust but I was worried that somebody had cleaned the front element so much that they had removed the coating. Can't decide if I should return it. Yesterday I spent the afternoon wandering around snapping anything in view just to try it out and found my handheld technique wanting! Also when zooming it moved out of focus slightly. I have to zoom very carefully for mine to stay in focus throughout but it does. As for the CA, I think it's as much a product of condition and setting than anything else. This one was done wide open.. Different conditions because I actually had a blue sky for the shot. I think though that if the sky were white, CA abound in the OOF trees. Couldn't tell you the actual focal length. Had the camera set to 100mm and left it there. The reason I asked about a filter is because your shots look a little foggy to me. A type of glow around the CA areas. Usually when I see CA or color fringing, it's a more well defined outline.

03-03-2010, 10:11 PM	#7
sterretje Veteran Member Join Date: Dec 2008 Location: Roodepoort, South Africa Photos: Gallery \| Albums Posts: 3,561	I agree with dadipentak. First advice is usually to use a narrower aperture. I also noticed (during recent tests with an FA31 on a K10D): Correct exposure on the contrasty area is very important; my testshots were pink flowers on green leafes; using matrix metering or centerweight in this scene did not do it and spot metering improved the results a bit (at least the flowers started to turn out pink instead of white). Your scene is the opposite and I think that underexposing will improve the situation. The standard JPEG settings of the camera worsen the purple fringing (raw format hardly shows the fringing); this was an absolute eye opener for me; point 1 above was still with standard JPEG settings Due to point 2, I have now set the jpeg engine's parameters in the camera to neutral as I want them to reflect the raw image. Not sure if I will keep it like that but for now it is.

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03-03-2010, 08:17 PM	#2
dadipentak Site Supporter Join Date: Jul 2008 Location: Baltimore, Maryland Photos: Gallery Posts: 11,590	Yeah, that's to be expected in high contrast areas like that. It's not all that difficult to deal with in PP--desaturate and darken it. That's one of my favorite lenses, btw.

03-03-2010, 08:27 PM	#3
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	That is mostly flare with some CA thrown in for spice. Steve

03-03-2010, 08:36 PM	#4
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	Do you have a filter on the lens? Are you shooting wide open?