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PeterD
15th October 2008, 09:46 AM
Hi all

I have noticed that the white balance is is sometimes fooled when shooting with the Bigma attached. I have, until now relied on Auto White Balance.

Could any of you Bigma owners comment on this please? What has your experience been and do you use auto?

Thanks

Peter

andym
15th October 2008, 09:57 AM
I think the Bigma is less contrasty(is that a word??)than the Olympus lenses and therefore images are a bit flatter and require some adjustment..
I do use Auto W/B unless its very sunny when I will set the W/B to 5200.
As I shoot raw the W/b sometimes get a bit of adjustment.

PeterD
15th October 2008, 10:41 AM
I think the Bigma is less contrasty(is that a word??)than the Olympus lenses and therefore images are a bit flatter and require some adjustment..
I do use Auto W/B unless its very sunny when I will set the W/B to 5200.
As I shoot raw the W/b sometimes get a bit of adjustment.

Thanks for your comments Andy. I do agree with you about the contrast and make sure this is one area of adjustment that I make. I had thought Auto W/B was Ok until I debveloped some images yesterday. These were taken on a very overcast and dull day but found that the W/B was set towards sunny. Re-adjustment in Lightroom corrected this. I am wondering if the long lens fitted to the E3 is in some way affecting the Auto W/B setting.

Cheers

Peter

photo_owl
15th October 2008, 11:06 AM
it shouldn't affect the E3 Auto WB surely as it's sensing the WB outwith the lens - where most of the E bodies will do it through the lens?

the lens impacting on the actual white balance of the image is another thing of course...

PeterD
15th October 2008, 11:25 AM
it shouldn't affect the E3 Auto WB surely as it's sensing the WB outwith the lens - where most of the E bodies will do it through the lens?

the lens impacting on the actual white balance of the image is another thing of course...

Now thats a good point that I had NOT considered:o.
Where I was coming from was that one of the white balance sensors is located at the front of the camera, near the lens. The W/B, as I understand it, is calculated by two sensors. I was wondering if a particularly long lens (the Bigma) could upset this.
Its no great issue as I could always adjust the W/B manually. I was just curious to know if anyone else had experienced problems when using the Bigma.

PeterD

Jim Ford
15th October 2008, 11:54 AM
I do use Auto W/B unless its very sunny when I will set the W/B to 5200.
As I shoot raw the W/b sometimes get a bit of adjustment.

My understanding is that if you shoot raw, the white balance setting on the camera has no effect. Raw means that the data is as captured by the sensor's photosites - just greyscale with no colour information whatsoever.

Jim

andym
15th October 2008, 11:59 AM
My understanding is that if you shoot raw, the white balance setting on the camera has no effect. Raw means that the data is as captured by the sensor's photosites - just greyscale with no colour information whatsoever.

Jim


But its got to start somewhere when it displays the image and as I understand it it takes the W/B as recorded as the starting reference.

PeterD
15th October 2008, 12:04 PM
I have to agree with Andy on this. I shoot RAW but expect the W/B to be set correctly. Its only the image processing which is not carried out in the RAW mode.

Peter

Ian
15th October 2008, 12:33 PM
My understanding is that if you shoot raw, the white balance setting on the camera has no effect. Raw means that the data is as captured by the sensor's photosites - just greyscale with no colour information whatsoever.

Jim

Even in RAW, the white balance selected by the camera in AWB (or in manual setting) will be recorded to the file. A RAW development program will usually use the recorded value as its default for that image.

But of course the value can be changed using your RAW software throughout the full range and the changes will be much more consistent than when changing the white balance of a JPEG file because there the primary colours have already been mixed.

Ian

Nick Temple-Fry
15th October 2008, 12:51 PM
But of course the value can be changed using your RAW software throughout the full range and the changes will be much more consistent than when changing the white balance of a JPEG file because there the primary colours have already been mixed.

Ian

Which is one of the reasons I favour raw shooting, I can 'compromise' the data after I've applied some of the overall corrections.

But back to Peters query - I've noticed a similar effect when shooting with the 135-400 + ec1.4. I've put it down to either

a) inadvertently shading (or putting into shade because of location) the wb sensor.

2) at the kind of distances we use these lenses - well the wb may actually be different - a bit of reflected light or local shade.

Outdoors the wb alters constantly as we move in/out of shade etc and as the cloud cover alters; I think the auto wb on the E-3 does a damn fine job, in my experience less than 1% 'failure', but maybe we expect a bit too much from it at times.

Nick

PeterD
15th October 2008, 03:11 PM
Which is one of the reasons I favour raw shooting, I can 'compromise' the data after I've applied some of the overall corrections.

But back to Peters query - I've noticed a similar effect when shooting with the 135-400 + ec1.4. I've put it down to either

a) inadvertently shading (or putting into shade because of location) the wb sensor.

2) at the kind of distances we use these lenses - well the wb may actually be different - a bit of reflected light or local shade.

Outdoors the wb alters constantly as we move in/out of shade etc and as the cloud cover alters; I think the auto wb on the E-3 does a damn fine job, in my experience less than 1% 'failure', but maybe we expect a bit too much from it at times.

Nick

Nick,

I obviously agree with the first point as that is my thinking too. Your second point is something I had not thought about but am coming round to agreeing with you. If you are using 'spot' metering, something we do when taking images of birds etc, the chances of changes in W/B must be quite high. Certainly higher than either of the other two exposure modes. I think you are on to something there.

Peter

Henk
15th October 2008, 03:20 PM
I don't have any of the big Sigma lenses so I'm just guessing; could it be that you get too close to the WB sensor with your fingers/glove when handling the camera with a heavy lens? I noticed that even in normal use my index finger sometimes gets close to the WB sensor.

Cheers,
Henk

PeterD
15th October 2008, 03:30 PM
I don't have any of the big Sigma lenses so I'm just guessing; could it be that you get too close to the WB sensor with your fingers/glove when handling the camera with a heavy lens? I noticed that even in normal use my index finger sometimes gets close to the WB sensor.

Cheers,
Henk

Henk,

With a big heavy lens, which the Bigma certainly is, the holding technique I have adopted is completely different. I support the whole camera and lens with the left hand and the right merely acts as a steady. I don't think I am covering the sensor but, perhaps I may be obstructing it with my left hand as I have removed the tripod mounting bracket from the lens.

Peter