topic Re: Lines running down photos on Rebel T6i in EOS DSLR & Mirrorless Cameras

Lines running down photos on Rebel T6i

meghanmoran — Sat, 12 Nov 2022 13:47:02 GMT

Hi everyone - I’m having a reoccurring issue where I’m getting a line running down/across my photos when I’m trying to shoot in lowlight indoors or at night. It looks yellow at first glance but when you zoom in it looks like red and white pixels. I’m not sure if it’s a camera issue or my settings, any ideas?

Re: Lines running down photos on Rebel T6i

deebatman316 — Sat, 12 Nov 2022 14:02:14 GMT

Hello meghanmoran welcome to the forums. Can you please post a picture to show what's going on with your camera. Also can you post the EXIF data intact too. Please also list the lens and external flash (if used) too.

-Demetrius

EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM & EF 70-200mm F/2.8L IS III USM

EOS 40D & 5D Mark IV

430EX III-RT & 600EX II-RT

Re: Lines running down photos on Rebel T6i

meghanmoran — Sun, 13 Nov 2022 17:37:40 GMT

Re: Lines running down photos on Rebel T6i

deebatman316 — Sun, 13 Nov 2022 17:50:49 GMT

I noticed that a high ISO was used. Leading to a noisy or grainy picture. What you're seeing is what are called hot pixels. That's what those red and white dots are in the picture. What mode was the camera used in. What lens was used to take this picture.

-Demetrius

EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 28-135mm F/3.5-5.6 IS USM, EF 50 F/1.8 STM & EF 70-200mm F/2.8L IS III USM

EOS 40D & 5D Mark IV

430EX III-RT & 600EX II-RT

Re: Lines running down photos on Rebel T6i

Lotus7 — Mon, 14 Nov 2022 17:42:17 GMT

I presume you're concerned about the single horizontal line of noisy pixels, not the "normal" high-ISO uniform "background" noise (technically: statistical quantum mottle) throughout the frame.

Single "noise line"I'm also presuming that you've tried another SD card AND the the "noise Line" is visible on the camera's LCD display (using display magnification to see the line) as well as on the exported data. IF it is not visible on the LCD at high magnification, it may indicate a data transfer or data storage issue.

Is that line at the same location on every frame? On your sample image it's at 36.3 % of the vertical image space. If it is always at the same location, and if it increases in intensity as you raise your ISO setting, it may be an indication of a failing image sensor. More specifically (on a CMOS sensor) a "row analog processor" or "row decoder". If it moves (occurs at random locations, It can indicate a failing clock circuit or interfering electronic noise from another source. The image you posted has been compressed by the website so it's hard to see exactly what the data looks like, but at first glance it appears to be random variable intensity noise along one scan row only, even though the convolution filter applied in-camera to reduce (smooth) the normal sensor noise has spread the excessively noisy row out over 4 or 5 rows.

This "row only noise" is not normal for your camera at ISO 6400. Again, if it's always at the same location, it's most likely a physical issue in the sensor array. If it occurs at a random location on successive frames, there are a multitude of possible causes including a faulty DIGIC 6 main processor.

Ideally, a RAW image data set should be checked, since any processing of the image such as converting it to a jpeg image will spatially filter the data and make it more difficult to determine what is actually happening.