Are these horizontal bright bands normal?

cloud_cover · Post by **cloud_cover** » Thu Jan 27, 2011 11:54 pm

After trying photography with my D700, I noticed these bright bands forming across my picture corresponding to objects of increased brightness.
Is this normal? I asked Nikon and they replied that this is "characteristic behaviour" of the D700 sensor.

Of course the yellow arrows are a photoshop edit to highlight the bright band. They didn't come with the camera

Post by **rcj** » Fri Jan 28, 2011 1:17 am

this is interesting....i do observe this banding with my astro ccd cameras as well...but it only shows up with extreme stretching of the image especially when it is very "dark" to start off with. Did u do any form of stretching for these images? I notice the first image seems to have some stretching done prior, but the second image does not seem so...

anyway, this form of banding occurs on particular ISO ranges (the higher ones, greater sensitivity) and usually comes when there are photosite areas on the chip that are overexposed... when these photosites are drained off, they are usually done alternating and handled by two circuits and drained in different ways. Two sets of data are thus collected, but ultimately, they end up in one big array of data. With some photosites near/adjacent to overexposed photosites, there could be some leakage, and with the unloading character of the chip, this probably results in the banding... which can be minimized through stacking...

cloud_cover · Post by **cloud_cover** » Fri Jan 28, 2011 10:38 am

Unfortunately stacking gives rise to a series of interrupted vertical bands...
Check out these unenhanced night photos:

This is unprocessed from the camera RAW

Again unprocessed. Please ignore the camera shake; I was just trying exposures, not tripod shots.

orly_andico · Post by **orly_andico** » Fri Jan 28, 2011 10:42 am

man that sucks.

but yes it is a "feature" or perhaps mis-feature of the sensor. i've seen that happen when there's over-exposure, since the sensor reads out the data in rows, if there's an over-exposed area, this "bleeds" into all the pixels on the same row.

the only work-around i can think of is, lower the ISO and lower your exposure. You don't have to be all the way on the right of the histogram, the only requirement is that the histogram detaches from the left side, that's good enough.

cloud_cover · Post by **cloud_cover** » Fri Jan 28, 2011 11:58 am

Darn. You mean I have to accept this from a 3K plus camera that's marketed as a professional body?

Post by **rcj** » Fri Jan 28, 2011 12:26 pm

yeah thats not too good. looks like the error banding is more systematic. if i were u, return the camera back to nikon and tell them to FIX it. whats the point of not enjoying the use of high isos? is this still a relatively new camera that u bought? brought this up to clubsnap for further discussion? is this a trait in for all those having this same model?

cloud_cover · Post by **cloud_cover** » Fri Jan 28, 2011 12:42 pm

Actually I've taken photos of night scenes but never like this.
But Nikon says its normal. Anyway I just sent back the email again and asked them to re-assess. Hopefully they'll be able to get back to me. I can't fathom why this doesn't happen on the D70 but only on the D700. The tech rep said the D3 doesn't have this problem (but it uses the same sensor?) so advised me to upgrade.
I might just switch to canon

orly_andico · Post by **orly_andico** » Fri Jan 28, 2011 1:05 pm

them's fighting words Kevin!

but like I pointed out in Christian Buil's article that I sent you... he concludes that the D3 sensor is "no better" than the Canon 40D...! something to think about..

(of course the D3 has a much greater full-well capacity, thanks to the physically 4X larger photosites, but in terms of noise, it's comparable)

cloud_cover · Post by **cloud_cover** » Fri Jan 28, 2011 2:00 pm

Remus --> Thanks for the advice. I've posted on clubsnap.
Trouble is Nikon already says there's nothing to fix so sending it back won't do anything but deprive me of my camera.
Or I guess I could just try not to use my D700 at night, maybe use my D70 instead or my wife's Finepix F10 (a point and shoot) since there are no lines like this.

Post by **rcj** » Fri Jan 28, 2011 2:04 pm

yeah probably . used to have the D70 , but did not have this issue. looks like some of sony's chips also exhibit this effect, which i believe has an official term - the Corduroy Effect (if spelt correctly). lol....