Luminous Landscape Forum

Equipment & Techniques => Cameras, Lenses and Shooting gear => Topic started by: thierrylegros396 on December 12, 2009, 01:15:17 pm

Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: thierrylegros396 on December 12, 2009, 01:15:17 pm
S90 users, did you notice that firmware bug ?!

When I shoot at ISO1600 there is a strong yellow-orange cast that does not appears at other ISO !

But at other high ISO, some yellow shadows appears sometimes.



Attachments are ISO800, 1000, 1250, 1600, 2000, 2500, 3200.

Have a Nice Day

Thierry
Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: thierrylegros396 on December 14, 2009, 04:22:43 am
Well, it seems to be a white balance problem.

But why only at ISO1600  

And here at University, I'm not able to reproduce the problem !

Very strange.

So I will investigate futher.


Have a Nice Day.

Thierry
Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: pegelli on December 14, 2009, 07:29:29 am
Quote from: thierrylegros396
Well, it seems to be a white balance problem.

One way to find out is shoot raw and see if it's indeed an AWB problem or that the colours of the shots are really different.
Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: dasrocket on December 14, 2009, 06:45:23 pm
Quote from: pegelli
One way to find out is shoot raw and see if it's indeed an AWB problem or that the colours of the shots are really different.


Nope, just did a test and had no adverse cast at 1600.

george.
Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: gingerbaker on December 23, 2009, 11:24:57 am
Quote from: thierrylegros396
S90 users, did you notice that firmware bug ?!

When I shoot at ISO1600 there is a strong yellow-orange cast that does not appears at other ISO !

But at other high ISO, some yellow shadows appears sometimes.



Attachments are ISO800, 1000, 1250, 1600, 2000, 2500, 3200.

Have a Nice Day

Thierry

Is it possible that ISO 1600 is producing a shutter speed that happens to hit a sour spot with the artificial lighting in the room in which you took the picture?  Getting inconsistent white balance problems would tell me you are seeing the effects of the natural frequency shifts of certain types of artificial lights.

Perhaps try shooting outdoors in natural light and see if you can repeat the phenomenon.  
Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: thierrylegros396 on December 24, 2009, 05:25:57 am
Quote from: gingerbaker
Is it possible that ISO 1600 is producing a shutter speed that happens to hit a sour spot with the artificial lighting in the room in which you took the picture?  Getting inconsistent white balance problems would tell me you are seeing the effects of the natural frequency shifts of certain types of artificial lights.

Perhaps try shooting outdoors in natural light and see if you can repeat the phenomenon.  

Yes the problem seems to produce especially indoor !

Thierry
Title: S90 users, did you notice yellow ISO1600 color cast ?!
Post by: Jonathan Wienke on December 24, 2009, 06:30:00 am
Quote from: gingerbaker
Is it possible that ISO 1600 is producing a shutter speed that happens to hit a sour spot with the artificial lighting in the room in which you took the picture?  Getting inconsistent white balance problems would tell me you are seeing the effects of the natural frequency shifts of certain types of artificial lights.

This is a big problem when using a shutter speed faster than 1/60 or so with fluorescent, mercury vapor, or sodium vapor lights. The lights are not continuous, they actually flash on and off at a frequency twice the AC line frequency. If the shutter opens while the AC line voltage is near its peak, you get a good exposure and white balance. But if the shutter opens while the AC line voltage is crossing zero, you get an underexposed shot with bad white balance. It's the bane of sports shooters who have to work in gyms with the wrong kind of lighting. Do a google search on light cycling and you'll find no end of complaints about this.

Nice avatar...