Did I reach the R3 sensor readout limits?

[John Sheehy]

Thanks Horshack. Would a readout where the rows were not adjacent to each other have some improvements so that it wouldn't create bands?

No matter what order you read them, you're going to get motion artifacts. In sequential order, whether by line or strip, you have the simplest artifacts.

The visuals will change in that you won't have effective wide bands / strips. If we spread them out across the sensor perhaps it's more acceptable to the human eye.

You could get individual lines that are completely different than their neighbors, if you jump around.

Let's take a strobing light source. If you jump around, you could have a single line captured when the strobe was on, surrounded by lines when the strobe was off. The same would happen in the explosion; you'd have single lines darker or brighter than their neighbors, and you may be able to see that as easily or easier than the strips in the OP's image.

 

[fijnheid]

Are you absolutely certain that the test tube did not have illumination?

Strobing lights just cause a difference in the scene (brightness or color) during an exposure. However they are not the only way to cause a difference during an exposure. If anything significantly changes (spatially or in brightness or color) during an exposure, no matter the source, then that can have some visible effect on the readout.

Yes, I know how that works, and I haven't denied that this may be at least part of the artifact, especially on the left side of the test tube, where it does like strips of different exposure times. However, a few things suggested to me a high-frequency strobe. When one is presenting an example of a sensor problem, the best thing is to supply a raw, or if not a raw, a conversion that is 1:1 with no lens corrections. The sRGB out put of RawDigger or FastRawViewer is uncorrected. If I saw a seam at exactly every 12 pixels, in the entire affected area, I would have been more likely to attribute it all to the 12-row parallel readout. What we actually have in the JPEG provided does not look like strips in the middle and the right parts of the affected area; it looks like a modulation from a duty cycle, possibly because of JPEG sharpening of the seams, combined geometric lens correction. The processing turned the edges of the strips into a mess.

Noted. I opted against that because I didn't know an easy way to add a large non-photo file attachment here, and there's several kids in the image, one of which I know wasn't supposed to be shared on social media. Just making sure I'm not breaking any GDPR-type rules.

I'll disable lens corrections and provide the 100% crop again, though. (Sorry for not doing so earlier; I hadn't changed anything on the sliders and assumed that meant it was unedited, but the lens correction profile was enabled by default.)





The left side of the image is the edge, in this case (the 'top' part of the camera, as it was in portrait mode).

Also thanks for your informative responses, they've been very interesting to read.

 

[Ephemeris]

Thanks Horshack. Would a readout where the rows were not adjacent to each other have some improvements so that it wouldn't create bands?

No matter what order you read them, you're going to get motion artifacts. In sequential order, whether by line or strip, you have the simplest artifacts.

The visuals will change in that you won't have effective wide bands / strips. If we spread them out across the sensor perhaps it's more acceptable to the human eye.

You could get individual lines that are completely different than their neighbors, if you jump around.

Then would they not be much less visible? A pixel worth Vs a band sounds like it has advantages

Let's take a strobing light source. If you jump around, you could have a single line captured when the strobe was on, surrounded by lines when the strobe was off. The same would happen in the explosion; you'd have single lines darker or brighter than their neighbors, and you may be able to see that as easily or easier than the strips in the OP's image.

Indeed, but I'm suggesting the effect would be more acceptable to the eye than a wide band of bright/dark/etc.

If one changes one line of pixels by reducing its exposure by an equivalent to 1 stop, would it be so obvious or even detected by a viewer?

--
Beware of correct answers to wrong questions.
John
http://www.pbase.com/image/55384958.jpg

 

[John Sheehy]

Noted. I opted against that because I didn't know an easy way to add a large non-photo file attachment here, and there's several kids in the image, one of which I know wasn't supposed to be shared on social media. Just making sure I'm not breaking any GDPR-type rules.

There really should be ways of cropping or partially redacting raws, but it has not become a thing.

I'll disable lens corrections and provide the 100% crop again, though. (Sorry for not doing so earlier; I hadn't changed anything on the sliders and assumed that meant it was unedited, but the lens correction profile was enabled by default.)

The left side of the image is the edge, in this case (the 'top' part of the camera, as it was in portrait mode).

I meant the left of the area with banding, where there is much more of a gradient. Anyway, the new image does have exactly 12.0 pixels per period.

Also thanks for your informative responses, they've been very interesting to read.

 

[John Sheehy]

You could get individual lines that are completely different than their neighbors, if you jump around.

Then would they not be much less visible? A pixel worth Vs a band sounds like it has advantages

Let's take a strobing light source. If you jump around, you could have a single line captured when the strobe was on, surrounded by lines when the strobe was off. The same would happen in the explosion; you'd have single lines darker or brighter than their neighbors, and you may be able to see that as easily or easier than the strips in the OP's image.

Indeed, but I'm suggesting the effect would be more acceptable to the eye than a wide band of bright/dark/etc.

If one changes one line of pixels by reducing its exposure by an equivalent to 1 stop, would it be so obvious or even detected by a viewer?

It doesn't take much of a difference in brightness to see a single line. Single pixels can easily vanish; entire lines; not so easily.

Do you have a specific pattern in mind?

You could do something like break the sensor into 12 strips and read a line from each, and that could randomize some strobing patterns so that you don't see them at very low magnification, but with higher magnification, it would be a mess with strobing lights. For the slant of panning, however, it would be a disaster.

 

[Ephemeris]

You could get individual lines that are completely different than their neighbors, if you jump around.

Then would they not be much less visible? A pixel worth Vs a band sounds like it has advantages

Let's take a strobing light source. If you jump around, you could have a single line captured when the strobe was on, surrounded by lines when the strobe was off. The same would happen in the explosion; you'd have single lines darker or brighter than their neighbors, and you may be able to see that as easily or easier than the strips in the OP's image.

Indeed, but I'm suggesting the effect would be more acceptable to the eye than a wide band of bright/dark/etc.

If one changes one line of pixels by reducing its exposure by an equivalent to 1 stop, would it be so obvious or even detected by a viewer?

It doesn't take much of a difference in brightness to see a single line. Single pixels can easily vanish; entire lines; not so easily.

Do you have a specific pattern in mind?

Something to avoid bands, so perhaps simple gaps (n+100 for example).

You could do something like break the sensor into 12 strips and read a line from each, and that could randomize some strobing patterns so that you don't see them at very low magnification, but with higher magnification, it would be a mess with strobing lights. For the slant of panning, however, it would be a disaster.

Yea I think that sounds similar to what I was thinking. Panning, ah I hadn't thought about that. I suppose one would need to read it very quickly to negate that but good point. Thanks John

--
Beware of correct answers to wrong questions.
John
http://www.pbase.com/image/55384958.jpg