purple highlights

[Jamesmd]

Hi Georg, fun to talk about Air on a CA thread . . That is left surround ,I calibrate them weekly and it's fine . It's a film premix room with the academy film eq aplaid . Don't worry it's fine and measured . The real reason for the pot is that directors and producers lean on them or leave there coffe there , so I opted for the flowers better . I do sound desing not musician , but I would love to be . We can talk of our stuff on private if you want or well bore people here.

Great that you recogniced the system and a surprise

Cheers

 

[fotografz]

Hi all

is the purple for highlights out of focus ?

James

Use or non-use of filters isn't necessarily the issue you are experiencing. The Zeiss ZA 85/1.4 exhibits some CA and/or sensor bloom in some conditions without any filters attached to the lens.

Much of it can be cleaned up by checking both the Purple Fringing and the CA boxes in Phase One C1. Most, but not necessarily all of it all of the time, will be removed.

Marc

 

[Jamesmd]

Hi Marc , I have C1 and I'll try it for sure , but I normaly use aperture . Do you know if aperture has some way of doing the same thing ?

Thanks

James

 

[Eoin]

James, When I got the ZA 85 and used it for the first time I though "yuck". Lots of purple fringing and LoCA. But the more I use it and have refined my exposure technique the less I see this problem.

I don't know if the purple fringing is a sensor bloom problem or a lens problem.

 

[edwardkaraa]

I don't know if the purple fringing is a sensor bloom problem or a lens problem.

It's probably the combination of both. Some high contrast lenses like the ZA85 and ZF100 seem to cause it more often than other lower contrast lenses. Though it's not really the lens' fault.

The ZA85 does has a very particular LoCA that shows in certain situations. Doesn't disturb me though.

 

[Georg Baumann]

The real reason for the pot is that directors and producers lean on them

THAT I would consider a declaration of war with an immediate response of the strongest possible measure. :cussing:

:ROTFL:

 

[fotografz]

Hi Marc , I have C1 and I'll try it for sure , but I normally use aperture . Do you know if aperture has some way of doing the same thing ?

Thanks

James

Well, I normally use Light Room for it's faster workflow. But when the occasional need to process an image with CA like the ZA 85/1.4 sometimes produces, or when processing a more troublesome high ISO files from the A900, I just import those images into C! which generally does a better job at both of those functions than most anything else ... at least better than LR/PS does.

I have Aperture on my machine, but never use it. So I can't remember if it has CA/Purple Fringing correction or not. Probably CA ... but C1 does it so well and so easily, and it's a relatively infrequent need ... if you have C1 I'd recommend it.

However, it would be good for you to look and see if Aperture has a decent ability to remove CA since it's your favored workflow.

 

[viablex1]

All filters introduce some degree of image degradation.
if you insist, a B+W 010 MRC is one of the least offensive.
-bob

that is what I always heard ...

also for purple fringing, a quick and dirty is to use hue saturation and choose blues or whatever, works like a charm provide you dont have any relevant hues close to it...

 

[Braeside]

Unfortunately Aperture STILL lacks CA controls. You have to use a plugin like PTLENS to eliminate it with Aperture, this means creating a huge TIFF file. I'm really hoping Apple add CA control to the next release of Aperture (if it ever comes).

Best CA tools I have seen are in DxO, but unfortunately they don't support all of my lenses, and have a particular green tint problem at present (with the A900).

 

[ryc]

here is purple for you

http://forum.getdpi.com/forum/showthread.php?t=7773

 

[Jamesmd]

just discovered you all talk about C1 Pro , no ?

Thnaks

James

 

[douglasf13]

What's interesting is some say that UV filters, if anything, should probably help with purple fringing, not hurt, so I'm probably crazy!

 

[Jamesmd]

PTLenns doesn't manage to fix it .

james

 

[Eoin]

James,

Where is the CA in this photo?. Is it the edge of the table?.

 

[Jamesmd]

Hi Eoin, yes and the top of the tin much more, Ill send beter file

 

[Braeside]

Sorry I should have been clearer, PTLENS fixes CA (Transverse but not Longitudinal though). It doesn't generally fix PF.

DxO does make a good job of fixing PF.

 

[Jamesmd]

here it is

 

[Braeside]

That is longitudinal CA - see the green around the out of focus at the rear of the lip of the can and the magenta at the out of focus at the front of the can.

 

[Eoin]

OK, for those of you (like me) who use Aperture, you may already know that the moire removal sliders in the Raw fine tuning brick can be used to remove light CA.
If the CA is stronger and the moire sliders do not remove it you can then use the Colour brick and carefully select the offending CA and play with the H,S,L,R sliders to zone in on the CA and eliminate it without having too much of an impact on the tones in your image.

 

[Jamesmd]

I've just done the same shot with and without VU and its worst with.

Ill send pics right now .

Can you do similar test to se if you have it ?

its 100 ISO , 1,4 F .