Archived posting to the Leica Users Group, 2006/07/06

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Subject: [Leica] Tale of Two Telyts Part Deax - The Evil Twin
From: philippe.orlent at pandora.be (Philippe Orlent)
Date: Thu Jul 6 12:36:41 2006
References: <0c6a689957fb15b7e15c496265b09547@depaul.edu>

Can't help you with your technical questions, but -with this title-  
wouldn't tis one look great in a (slightly warm grey toned) B&W?
Just an idea.
Thanks for showing,
Philippe



Op 6-jul-06, om 17:41 heeft bob palmieri het volgende geschreven:

> Folks -
>
> As promised, here's an example of a disturbing symptom I encounter  
> occasionally with the 400 Telyt.
>
> Here's a snap of a blue heron impersonating a stick:
>
> http://gallery.leica-users.org/album409/Camoflage_Heron_Crop
>
>
> And here's a 100% pixel crop showing heavy purple fringing around  
> the feet and along the top edge of the log (in areas of serious  
> overexposure):
>
> http://gallery.leica-users.org/album409/Camoflage_Heron_PurpleCrop
>
>
> I've seen the same effect on Kodachrome, so I don't think it's one  
> of those artifacts of digital sensor architecture (despite all the  
> talk you hear about purple fringing in digicams.)  My questions are  
> as follows:
>
> 1. Is this just a classic case of chromatic aberration in a simple  
> achromat? (I hear tell that the Anomalous Dispersion glass  
> (whatever that is) in this design is supposed to control this  
> kindof thing to a pretty acceptable level.)
>
> 2. If so, is it really possible that the results in the normally  
> exposed areas can look as good as they do (not that this snap is  
> the best example; things were getting pretty dim at the time and  
> the shutter speed was probably quite low) with a level of CA this  
> high?
>
> 3. Does someone who uses both this lens and the probably  
> staggeringly CA-free 280 APO (Doug??) ever see this effect in their  
> 400 shots and not in those shot with the APO ?
>
> Inquiring minds want to know...
>
> Bob Palmieri
>
> _______________________________________________
> Leica Users Group.
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>


In reply to: Message from rpalmier at depaul.edu (bob palmieri) ([Leica] Tale of Two Telyts Part Deax - The Evil Twin)