K5 & 70mm f2.4 Limited behavior...

ide508 · 02-20-2012, 06:22 AM

Hello there

I have recently bought the 70mm f2.4 Limited lens and I must say that, though in the learning process to master it, it is a wonderful peace of kit !
But I have a question concerning one particular shot.

In real time, the chair is grey as shown. This one was taken with the 70mm but I cannot reproduce it any more. Every time I try, I always get the colour of the second picture, which is obviously wrong!

I have tried to shoot (with the box on the chair) in between 100 -> 800 iso and from f2.4 -> 10 with no luck

If I shoot without the box, the grey of the chair is perfect. With the box on... Blue !

Can someone help me understanding why I could only get once the correct color and not any more?
Is it the lens fault and should I return it ? Both pictures were taken with the W/B on auto. I have zero problems elsewhere with tat lens...

I have tried the same with my 40mm 2.8 and at the same setting, the picture is also "a little" blueish but nothing compare as above. If I use 3.4 it's perfect!
Also tested it with the 50 1:1.4 at the same setting, it's very very very slightly blue at f2.8. and perfect at 3.5

Can we call that Xtreme purple fringe?

Many thanks for your ideas / suggestions

Cheers
Bernard

Jonathan Mac · 02-20-2012, 08:12 AM

The white balance is wrong in the second photo, though I can't see what each is set to because the EXIF data is chopped. If the auto WB is getting it wrong then set it manually using one of the pre-sets or a fully manual calibration.

ide508 · 02-20-2012, 09:58 AM

Originally posted by Jonathan Mac

The white balance is wrong in the second photo, though I can't see what each is set to because the EXIF data is chopped. If the auto WB is getting it wrong then set it manually using one of the pre-sets or a fully manual calibration.

Thanks for answering.
The Exif chopped should just read B/W -> Automatic
I will try to set it manually and... see!

Cheers

Marc Sabatella · 02-20-2012, 08:53 PM

Auto white balance is just a guessing game, based on looking at the colors in the photo and trying to figure out what color light might have produced those colors. Sometimes it guesses wrong, especially when bright colors are involved. Nothing to worry about.

ide508 · 02-21-2012, 12:23 AM

Thank you for that. At least I know that I own a box able to drive the K5 crazy

02-20-2012, 06:22 AM	#1
ide508 Junior Member Join Date: Dec 2010 Location: Gistoux Belgium Posts: 34	K5 & 70mm f2.4 Limited behavior... Hello there I have recently bought the 70mm f2.4 Limited lens and I must say that, though in the learning process to master it, it is a wonderful peace of kit ! But I have a question concerning one particular shot. In real time, the chair is grey as shown. This one was taken with the 70mm but I cannot reproduce it any more. Every time I try, I always get the colour of the second picture, which is obviously wrong! I have tried to shoot (with the box on the chair) in between 100 -> 800 iso and from f2.4 -> 10 with no luck If I shoot without the box, the grey of the chair is perfect. With the box on... Blue ! Can someone help me understanding why I could only get once the correct color and not any more? Is it the lens fault and should I return it ? Both pictures were taken with the W/B on auto. I have zero problems elsewhere with tat lens... I have tried the same with my 40mm 2.8 and at the same setting, the picture is also "a little" blueish but nothing compare as above. If I use 3.4 it's perfect! Also tested it with the 50 1:1.4 at the same setting, it's very very very slightly blue at f2.8. and perfect at 3.5 Can we call that Xtreme purple fringe? Many thanks for your ideas / suggestions Cheers Bernard

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
DA* 50-135 or 70mm limited and 40mm limited	freewheelin25	Pentax SLR Lens Discussion	22	11-08-2011 03:53 AM
PENTAX DA 70mm F2.4 Limited vs Sigma 17-70mm	Eric Seavey	Pentax SLR Lens Discussion	11	09-17-2011 06:18 AM
For Sale - Sold: Pentax DA 21mm Limited & Sigma 17-70mm f/2.8-4.5 DC Macro (CONUS)	RisingSun	Sold Items	2	06-10-2011 06:13 AM
For Sale - Sold: DA 70mm f2.4 limited & FA 50mm f1.4 (US/UK/CAN/AUS)	greasemonkey	Sold Items	7	08-10-2010 07:52 PM

02-20-2012, 08:12 AM	#2
Jonathan Mac Pentaxian Join Date: Apr 2009 Location: Madrid, Spain Posts: 10,897	The white balance is wrong in the second photo, though I can't see what each is set to because the EXIF data is chopped. If the auto WB is getting it wrong then set it manually using one of the pre-sets or a fully manual calibration.

02-20-2012, 09:58 AM	#3
ide508 Junior Member Join Date: Dec 2010 Location: Gistoux Belgium Posts: 34 Original Poster	Originally posted by Jonathan Mac The white balance is wrong in the second photo, though I can't see what each is set to because the EXIF data is chopped. If the auto WB is getting it wrong then set it manually using one of the pre-sets or a fully manual calibration. Thanks for answering. The Exif chopped should just read B/W -> Automatic I will try to set it manually and... see! Cheers

02-20-2012, 08:53 PM	#4
Marc Sabatella Veteran Member Join Date: Sep 2006 Location: Denver, CO Photos: Gallery Posts: 10,685	Auto white balance is just a guessing game, based on looking at the colors in the photo and trying to figure out what color light might have produced those colors. Sometimes it guesses wrong, especially when bright colors are involved. Nothing to worry about.

02-21-2012, 12:23 AM	#5
ide508 Junior Member Join Date: Dec 2010 Location: Gistoux Belgium Posts: 34 Original Poster	Thank you for that. At least I know that I own a box able to drive the K5 crazy