Issues with banding.

[akv]

Hi all,
I've been noticing that I've been getting banding on some images from time to time.
The major part of it is across the lower half of the frame when holding the camera normally.
I first noticed it when I used my Sigma EF 500 DG Flash wirelessly. There was very obvious banding on the lower half. In some other images I notice it but it's very faint.
In the test image I used to look for dust spots you can see it across the whole image.
And in the chipmunk image the camera was set at 1600Iso and I used the built in flash.
I sent an email to Sigma USA but they didn't say much, they didn't think it was an issue with using the wireless flash. And said I could send it in if I wanted.
Anyone else have these issues? I've got a Square Trade Warranty on the camera and I was wondering if I should send it in or not? Recently it only seems to show up in the high ISO shots and not always.

Thanks for any input!

 

[tc95]

Akv,

Unfortunatly...the Sigma's that are out are really bad over ISO 800....I have had issues with them unless it is in a concert enviroment...where there is not a lot of information that has to be transfered from the sensor to the memory card...I am not technical...but it seems to progressively get worse from ISO 400

ISO 400 OK
ISO 800 1/2 I get are bad
ISO 1600 1/5 of the shots are keepers...

I don't use my flash at anything over ISO 400 and really keep it to ISO 200 when using it....the images and colors seem to come out better...at ISO 800 I usually use the manual mode and play with the f-stop and exposure times....most of the shots are dark..but I let the Sigma software help me pull them back to where they need to be before I use PS or NX2 to edit them further...

Uwe or Klaus can give a better explination on why there is issues at ISO 800 and 1600...you might want to PM them...

Tony C.

 

[akv]

Thanks Tony,
I knew about the higher ISO issues that the SD14 has. But I've noticed the banding in shots where I used the flash in lower ISO settings. And the banding on 1600 seems to be a lot worse than some of the examples I've seen.
I hardly ever shoot above 400, unless I'm going to take the color out.

 

[Robert.4507]

Hi AKV,

Sorry to hear about the problems with your camera. Personally I have not seen banding like these two shots in the pictures from my SD14, and I have taken about 9000 pics with it.

good luck,

Robert

 

[Steaphany]

I have not seen this either, and you know my diverse SD14 uses, medium and long night and astronomical exposures do have noise, but no banding. One thing to keep in mind is I try to stay with ISO 100.

 

[akv]

thanks for the info guys,
It's not a permanent issue, it only comes along once in a while. Usually when I use the flash. I'm guessing it might be a battery issue too. I've got a CTA battery I bought from Cameta Camera, and I think that as it gets low on power maybe there's fluctuation in the charge or some other engineering based answer that I haven't the slightest clue about.
I think if it gets worse I can always send it in to Sigma, but really nothing major, more just an annoyance when it does happen.

 

[notalent]

I have seen this once with my SD14. I have just purchased the camera and taken only a couple dozen pictures so far. Here is the EXIF from the original picture.

Camera Model: SIGMA SD14
Image Date: 2009:04:18 09:37:06
Flash Used: Yes
Focal Length: 18.0mm (35mm equivalent: 30mm)
Exposure Time: 0.017 s (1/60)
Aperture: f/3.5
ISO equiv: 100
Exposure Bias: -0.70
White Balance: Auto
Metering Mode: Center Weight
Exposure: program (Auto)
Exposure Mode: Auto Bracketing

Sigma 18-50mm f3.5-5.6 DC Lens

Here is a crop:
View attachment 1524

 

[akv]

Thanks notalent!
I was starting to think it was something I was doing.
When I noticed it in the lower ISO settings for me I was using a 500 dg flash remotely. So I did trigger the in camera flash, that might be something we did in common. I get it mostly on the high ISO though but it doesn't happen very often at all, so I'm thinking it might be a battery issue.
My lines go horizontally when I hold the camera in landscape, and I notice that it's more visible in the lower half of the image (if you divide the image directly in half it becomes more prominent right at the middle).

 

[akv]

notalent,
Were you using the PG-21 battery grip when you took that shot?

 

[notalent]

notalent,
Were you using the PG-21 battery grip when you took that shot?

No, just the normal BP-21 battery that came with the camera.