Colours (again)

Ok, following-on from my thread earlier I though I had it sussed by using fixed White Balance, or maybe it was a lens issue, but...no!

Brand new, out of the box, DA 12-24.
Shooting RAW, AV Mode, ISO-200.
These two shots are less than a second apart, but the colours are quite different! ARGH!

Open them in adjacent tabs or similar and flick between them...
http://img90.imageshack.us/g/imgp0703.jpg/






Its more apparent full-size, but reduced by 1/4 for speed downloading!

Not done any processing, this is straight out of Pentax DCU-4 software.

What am I missing here? Yes I know the sky is blown-out, more concerned about the colours here not the exposure...

Please tell me I'm being a silly noob and not doing something obovious, its driving me nuts!

Not seeing what you're seeing I'm afraid

Did you use a fixed white balance here or not?

As for the lens, there is indeed differences between lenses but a lens will not change colour, there is no way it can do that

Look at the path and the green around it, in the first it's more yellowish and in the second more blueish.

I just looked at it on my laptop for comparison (normally look on a 30" S-IPS which has a Wide-Colour Gamut, 92% NTSC or something like that), its not so obvious on that - but you can still see the greens shift in tone, the path change colour, and the sky slightly. Its a tweak to the blue I think...

I should explain that I am very very picky about colour (its my job...)

Colour Temp. was fixed to "Daylight". According to the DCU, the only difference between these shots is the timestamp!

actually that's not true, the lens coatings are optimised for a specific wavelength and transmission coeficient of plane glass a function of wavelenth even before you add the coatings.

I would expect a variation in colour between different coating types (say SMC vs Tamron BBAR) and quite possibly between different generations from the same manufacturer.


The variation in colour between those two shots is very slight, I couldn't see it until I put them in separate tabs and flicked between them. Are you sure you processed both shots with the same white ballance? when shooting RAW it makes no difference what the camera is set to, only what the RAW conversion software was set to (unless the RAW software was set to "camera" of course).

if it was overcast and the clouds moved between shots the colour temperature of the light could easily change by enough to cause that colour shift in a few seconds. The sky seems quite burnt out so I can't tell if it was a cloudy day or not.

I'm saying that there is a difference between lenses but that a lens would not change his colour, I could expect a lens act a bit differently in daylight then under tungsten but I don't expect it to be more green first and a second later be blueish under the same light source.
Or are you really saying that a lens can change his colour behaviour in a second?

It was a very sunny afternoon, hardly any clouds, very bright sun (I'm still learning how to cope with this, got a big book on Exposure but theory and practice are quite different!)

1/100 sec, F-7.1, ISO-200.

Anyway, thanks to people's comments I'm thinking maybe its a software processing issue - i.e. crap freebie software - in combination with me not knowing how to use it - if anyone is brave enough to download 32meg of rubbish picture, you can look at the RAW files here

Well I dared to download them, took only 3 seconds

03 = temp 4700 / tint +1
04 = temp 4400 / tint +2

So the white balance isn't the same with both.
When I set the balance the same the colours are the same in both photos.

bugger, you're right.

Crap software then : the White Balance menu said "Camera setting - Daylight" for both, but if set Manual Override - Daylight they look the same (no colour shift between shots).

So its saying Fixed when it isn't.. hey ho... the software lies, great, another thing to spend money on replaceing, sigh...

Many Thanks again to everyone who's helped, I'll get the hang of this lark eventually...

Flossie for now you might want to try lightroom 3 beta2.
It's Beta software so not for actually reproduction use but it's fully functional till 30 June.

or you can have a look at silkypix, the Pentax software is based on that and many members use it.

As for spending money, Pentax is one of the few that offers the software for free so you can't complain much.

It might be user error with the software since I never used the software myself I've no idea how it works.

Just checked your camera settings and it was indeed set on "daylight" probably it's not a fixed value but you limit the range the AWB works.
I've no idea since I never use it.

Scary isn't it what you can find out?

Pentax Version: 51.0.0
Pentax Model Group: Group 1 (DSLR series & Various Optio models)
Preview Image Size: 640 x 480
Preview Image Length: 23025 bytes
Preview Image Start: 0x00008EC0
Pentax Model: K-x
Date: 2010-04-09
Time: 15:29:52
Quality: RAW
Flash Mode: Off, Did not fire; Internal
Focus Mode: AF-A
AF Point Selected: Auto
Exposure Time: 1/100"
F Number: F7.1
ISO: 200/24°
??? (0016): 50
Metering Mode: Multi-segment
Auto Bracketing: 0 EV, No Extended Bracket
White Balance: Daylight
Focal Length: 12 mm
Saturation: Normal
Contrast: Med High
Sharpness: Med Hard
DSP Firmware Version: 1.01.00.07
CPU Firmware Version: 1.01.00.07
Effective LV: 11.3 LV
Picture Mode: Aperture Priority; 1/3 EV steps
Drive Mode: Single-frame; No Timer; Shutter Button; Single Exposure
??? (0035): 12053, 8005
Color Space: sRGB
Image Area Offset: x = 10 px, y = 10 px
RAW Image Size: width = 4288 px, height = 2848 px
??? (003D): 8289
Preview Image Borders: top = 28, bottom = 28, left = 0, right = 0
Lens ID: 4 + 248 + 0 + 0
Pentax Lens Type: FA, FAJ, DFA or DA
Lens Name(s) of the ID: smc PENTAX-DA 12-24mm F4 ED AL [IF]
Camera Temperature: 30 °C
AE Lock: On
Noise Reduction: Off
Flash Exposure Compensation: ±0
Image Tone: Bright
Color Temperature: Not set
SR Result: stabilized
Shake Reduction (Setup): On
Shutter Release Half Press Time: 1.45 sec
SR Focal length: 12 mm
Shutter Count: 1049
??? (0060): 0, 0, 0, 0
??? (0062): 5
??? (0067): 1
??? (006: 1, 0
Dynamic Range Expansion: Off
??? (006B): 2, 0, 20, 21
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??? (0070): 0
High ISO Noise Reduction: Medium
??? (0071): 0
??? (0071): 56
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??? (0073): 65535
??? (0074): 65535
??? (0076): 0, 0
??? (0077): 0, 0
??? (007: 0, 0
??? (0079): 0, 0
Black Point: [49, 47, 47, 49]
White Point: [14464, 8288, 8288, 12640]
Picture Mode 2: Aperture Priority
Program Line: Normal
EV Steps: 1/3 EV steps
E-Dial In Program: P Shift
Aperture Ring Use: Permitted
Flash Options: Normal
Metering Mode (2): Multi-segment
AF Point Mode: Auto
Focus Mode 2: AF-A
AF Point Selected 2: 0
ISO Floor: 200/24°
Drive Mode 2: Single-frame
Exposure Bracket Step Size: 0.3
Bracket Shot Number: n/a
White Balance Set: Auto
Multiple Exposure Set: Off
??? (0205): 0
??? (0205): 0
??? (0205): 113
Lens Name: smc PENTAX-DA 12-24mm F4 ED AL [IF]
Pentax Lens Type: FA, FAJ, DFA or DA
Lens ID: 4 + 248
Additional Flags: New LensInfo format? (Bit 7)
Auto Aperture: On
Nominal Aperture Range: F4 - F22
Lens F-Stops: 5
Lens Kind / Version (LC0): 2 / 8
Lens Data (LC1): 214
Distance Code Data (LC2): Range: 03; Step: 7 (Code: 27; Very Far/Infinite)
K-Value (LC3): 79
Near Distance Abberation Correction Data (LC4): 99
Light Color Aberration Correction Data (LC5): 2
Open Aberration Data (LC6): 14
AF Minimum Actuation Condition Data (LC7): 102
Focal Length (LC: 11.9 mm
Nominal AVmin / AVmax (LC9): F4 / F22
mv' nv' Data (LC10): 114
AVC 1/EXP Data (LC11): 52
mv1 Avminsif Data (LC12): 2
AVmin Data (LC13): F4
UNT_12 UNT_6 Data (LC14): Not set
Incorporated Flash Suited END Data (LC15): 3
??? (0207): 255
??? (0207): 255
??? (0207): 255
??? (0207): 248
??? (0207): 9
??? (0207): 99
??? (0207): 2
??? (0207): 13
??? (0207): 0
??? (0207): 102
??? (0207): 6
??? (0207): 0
??? (0207): 0
??? (0207): 0
??? (0207): 0
??? (0207): 0
??? (0207): 0, 0, 0, 0, 0, 0, 0, 0
??? (0207): 0, 0, 0, 0, 0, 0, 3, 94, 139, 250, 205, 226, 19, 190, 90, 155, 30, 133, 170, 237, 6, 131
Flash Status: Off
Internal Flash Mode: Off, Normal
External Flash Mode: Off
Internal Flash Strength: 0
TTL D/A A-ch Up: 150
TTL D/A A-ch Down: 24
TTL D/A B-ch Up: 235
TTL D/A B-ch Down: 0
??? (020: 0
??? (020: 0
??? (020: 0
??? (020: 0
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??? (020: 0
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AE Metering Segment 1: 10.3 LV (center)
AE Metering Segment 2: 10.4 LV (center edge)
AE Metering Segment 3: 10.5 LV (upper, mid-right)
AE Metering Segment 4: 12.9 LV (upper, mid-left)
AE Metering Segment 5: 9.6 LV (upper, right)
AE Metering Segment 6: 12.8 LV (upper, left)
AE Metering Segment 7: 9.6 LV (mid-right)
AE Metering Segment 8: 10.9 LV (mid-left)
AE Metering Segment 9: 9.5 LV (right)
AE Metering Segment 10: 10.9 LV (left)
AE Metering Segment 11: 10.3 LV (lower, mid-right)
AE Metering Segment 12: 10.4 LV (lower, mid-left)
AE Metering Segment 13: 9.9 LV (lower, right)
AE Metering Segment 14: 10.4 LV (lower, left)
AE Metering Segment 15: 13 LV (top)
AE Metering Segment 16: 10.4 LV (bottom)
Flash Metering Segments: not set
Slave Flash Metering Segments: not set
Pentax Model: K-x
Manufacture Date?: 2009-09-15
Camera has been serviced?: Serviced bit not set (Value: 2?)
Production ID?: 2
Internal Serial Number?: 8010228
Number of Matrices: 16 matrices
Matrix 1: [12576, -3616, -768], [-1056, 11936, -2688], [224, -2912, 10880]
Matrix 2: [13606, -4167, -1247], [-1273, 12937, -3472], [-31, -4293, 12516]
Matrix 3: [13880, -4432, -1256], [-1794, 13448, -3462], [-342, -3607, 12141]
Matrix 4: [13941, -4561, -1188], [-1694, 13558, -3672], [-730, -4899, 13821]
Matrix 5: [15658, -6133, -1333], [-1621, 15119, -5306], [-184, -2845, 11221]
Matrix 6: [8725, -698, 165], [-640, 9476, -644], [52, -442, 8582]
Matrix 7: [12576, -3616, -768], [-1056, 11936, -2688], [224, -2912, 10880]
Matrix 8: [3189, 5576, -573], [3189, 5576, -573], [3189, 5576, -573]
Matrix 9: [1275, 8283, -1366], [1276, 8282, -1366], [1276, 8283, -1367]
Matrix 10: [3783, 5369, -960], [3783, 5369, -960], [3783, 5369, -960]
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??? (03FF): 1, 49, 47, 47, 49, 0, 14026, 0, 8192, 8289, 8192, 0, 0, 0, 48

This is a situation where you need to tweak the white balance in whatever RAW converter you are using.

Is tat also purple fringing on the trees? I wouldn't have expected that from the 12-24 .