whats with the blue??

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usccharles

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whats up with this nasty blue thing?

blue-vi.jpg


100%crop

bluecrop-vi.jpg


always happens when there is a bright background.

😕
 
Purple fringing usually is a result of chromatic aberrations when different colors of the spectrum are refracted through a glass lens. Purple and blue bend at a sharper angle than red.

Some modern lenses have so many glass elements one or more special aspherical elements are added to correct for this.
 
"purple fringing"
Are you using a digital camera? Usually it's because in highlights RGB pixels have a each one a different output.
I've seen also in "consumer" scanner, when the image on film has a sudden bright area (like in this one)
 
Part 2 - It starts at the lens, but the RGB pattern of pixels on the digital sensor, it is amplified.

Digital sensors have dedicated pixel sights for red, blue and green. I'm am definitely not qualified to say, but in my honest opinion this could happen on many different digital cameras, not just the M8. I could be wrong.
 
Sorry, I replied too slowly. It can happen on long lenses, but if you're using a 50mm I think it's because the digital sensor, not lens color aberrations.
(But it could be the ND filter, specially if it's not a pricey one I think... try shooting hard highlights with and without it)
 
Solinar said:
this could happen on many different digital cameras, not just the M8.
Click to expand...

It happens mostly with small sensor (like in compact digicams). I'm a bit surprised to see it on a APS sized camera in such a strong way...
 
It is quite common with digital cameras - some are worse than others - no real link to price paid. As Solinar says - it starts at the lens and is then amplified by the sensor. I'm an analog rangefinder user, but I get it under certain conditions with my Canon 20d and Pana LX1

Silva
 
You mean like this?

You mean like this?

You mean like this shot from my R-D1s? This happens regardless what lens I'm using depending on the lighting conditions with my Epson. I've not noticed it (yet) with my M8 but it never took away from my images shot with my R-D1.


Link to full size image:
http://farm1.static.flickr.com/143/322819245_b803b2530b_o.jpg

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usccharles said:
so this is a lens problem not a m8 problem??

lens was noctilux with a 3step ND filter
Click to expand...
I've noticed there is some residual cast when using my own "3 step" (0.9x) ND filter on my Summilux, even on the Summicron. The shadows and whites have a bluish cast. It makes no sense, for they're supposed to be neutral density filters.

I get this cast in both digital shots and slide film, here and there.
 
interesting... but somehow i guess i will never really know what the real problem is (lens, sensor, filter). cant use the noctilux without a ND filter on a bright day and i don't get this blue cast unless its bright out and lens is wide open 🙂

thanks for the inputs~
 
Why oh why would you want to use a Noctilux wide open on a bright sunny day? I guess the 1/8000 of a sec shutter is not fast enough at 160 ISO (200)
 
its my understanding that this is a lens problem, I have shots taken with a canon 17-40 on velvia 100f that show this on bright to dark areas
 
Sailor Ted said:
Why oh why would you want to use a Noctilux wide open on a bright sunny day? I guess the 1/8000 of a sec shutter is not fast enough at 160 ISO (200)
Click to expand...

yeah, 160 ISO isn't fast enough even with 1/8000 sec ona bright day. yesterday was my first day out with my noctilux during the day. come to think of it, it was my first time shooting color with my noct. its always been late at night with my delta 400 or 3200.

🙂 its really fun during the day too, i realize. 🙂
 
it's probably a lens thing. I've noticed this bloom on my 5D+85mm f/1.2. One time when I took 3 shots in succession at incoming traffic, one of the shot had this bloom while the others did not. I assume it has something to do with the angle at which the light enters the lens..
 
I found quite a lot of this on both of my M8s - using 50 'cron and Tri-Elmar. Also seen it (less often) with my Olympus E400 and Sigma 30mm, but not with Olympus lenses. Never on my E1 with Olympus lenses. Not found it on the R-D1. Didn't happen on my Nikon D70 either. It is normally associated with cheaper small sensor cameras. Never seen it on my B&W scans 🙂
 
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