Monochrome camera vs converting from color?

[Tim Lookingbill]

It would be very helpful if the facts behind the science discussed here can be applied shooting in real world situations as in shooting outdoors under constant changing dynamic range and white balance.

Show me how knowing the technical facts helps make a better photo.

I know one fact about optimal exposure not mentioned here and in Iliah's article on calibrating for such exposure on his site is that a photographer can't anticipate or predict the rate at which the sensor nears full saturation (relying only on jpeg based histograms) in order to prevent blown highlights or worse, flowers that turn into blobs of posterized color even when shot in low DR overcast daylight as in Iliah's flower example.

No one can explain why flowers would clip even in low overcast light since luminance levels of the scene define its color gamut.

It's this unpredictable nature of electrons/photons nearing full saturation on the sensor is what I deem a failure by technologists in their explanations that don't make the facts of science very practical for photographers.

[digitaldog]

It would be very helpful if the facts behind the science discussed here can be applied shooting in real world situations as in shooting outdoors under constant changing dynamic range and white balance.

Show me how knowing the technical facts helps make a better photo.

I know one fact about optimal exposure not mentioned here and in Iliah's article on calibrating for such exposure on his site is that a photographer can't anticipate or predict the rate at which the sensor nears full saturation (relying only on jpeg based histograms) in order to prevent blown highlights or worse, flowers that turn into blobs of posterized color even when shot in low DR overcast daylight as in Iliah's flower example.

No one can explain why flowers would clip even in low overcast light since luminance levels of the scene define its color gamut.

It's this unpredictable nature of electrons/photons nearing full saturation on the sensor is what I deem a failure by technologists in their explanations that don't make the facts of science very practical for photographers.

Do you know how to expose an image Tim? It’s somewhat a technical process! An aid in making better better images!

[Tim Lookingbill]

Do you know how to expose an image Tim? It’s somewhat a technical process! An aid in making better better images!

I've exposed well enough over 1000 Raws, Andrew. What's your point? You've got something to say that's useful about predicting and gauging the rate of speed when sensors near full saturation?

[Iliah]

a photographer can't anticipate or predict the rate at which the sensor nears full saturation

But a spotmeter can, if you meter from the highlights where you want to keep details.

No one can explain why flowers would clip even in low overcast light

I'm afraid I don't understand.

It's this unpredictable nature of electrons/photons nearing full saturation on the sensor

Sorry, nothing unpredictable here. Not to mention that among recent cameras, only with a few Panasonic models you can come close to full sensor saturation. Clipping point in raw is about 1+ stops below sensor saturation.

[Slobodan Blagojevic]

... in Iliah's article on calibrating for such exposure on his site...

Where can one find his site? I generally like to know more about the person behind anonymous Internet posts.

[Tim Lookingbill]

But a spotmeter can, if you meter from the highlights where you want to keep details.

That doesn't work all the time outdoors because now the photographer has to squeeze the dynamic range to fit the highlight whose intensity out in the field varies for instance the backs of sunlit white geese who are pruning their feathers. Each 1/3 stop adjust either way with the change of angle of the duck's back in order to preserve feather detail blows out or forces a SUB OPTIMAL EXPOSURE where the results are overly dark or blown feather detail.

I'm afraid I don't understand.

I'm referring to your demo image of the magenta flowers shot in overcast or shaded light in a concrete bird bath fixture you've used to explain optimal exposure. Why should flowers clip in low light? Can you explain how that happens on a sensor when the bird bath and surrounding greenery looks normally exposed.

Sorry, nothing unpredictable here. Not to mention that among recent cameras, only on a few Panasonic models you can come close to full sensor saturation. Clipping point in raw is about 1+ stops below sensor saturation.

You have not proved that and so you don't know that for sure because you refuse to understand my point of the unpredictable nature of light intensity changes shooting outdoors. You have two moving targets you haven't convinced me you know how to calculate effectively for practical use.

[Tim Lookingbill]

Where can one find his site? I generally like to know more about the person behind anonymous Internet posts.

Here's the calibration for optimal exposure article... https://www.rawdigger.com/howtouse/calibrate-exposure-meter-to-improve-dynamic-range

And here's the article showing the magenta flowers that clip even in overcast light... https://www.fastrawviewer.com/raw-histogram-for-culling

[Rob C]

None of this chest-thumping makes me want to buy a Leica Mono...

Nobody needs thump their chest for me to covet a Leica with all the colour gathering power it can get.

I could make all the black/whites my thumping little heart desires with the latter.

How far ego and the need to show expertise take folks away from the topic... or maybe, for them, that's what photography is all about: thumping.

;-)

Rob

[Iliah]

That doesn't work all the time outdoors because now the photographer has to squeeze the dynamic range to fit the highlight whose intensity out in the field varies for instance the backs of sunlit white geese who are pruning their feathers.

Nothing works all the time, Tim. But this one - not for the reason you've stated. Try and see. You will prove it for yourself. Should you have any questions, my e-mail is ib@pochtar.com

Why should ... clip

In raw something is clipped because of the wrong exposure settings. In JPEG fro two additional reasons: because of white balance and hidden exposure correction applied when rendering JPEGs. The article you've read explains that white balance is exposure correction, and that JPEG clipping point is best case half a stop below clipping point in raw. If you are using Canon, try Magic Lantern to see raw histogram. With other cameras you also have some useful options. I simply ignore JPEGs, they are a distraction when I shoot raw.

You have not proved that

That what? That the sensor clipping point and raw clipping point are different, and the difference is close to 1 stop? Oh come on... The tags I deciphered for Panasonic are part of free, documented, and open source ExifTool.

[Iliah]

the article showing the magenta flowers that clip even in overcast light... https://www.fastrawviewer.com/raw-histogram-for-culling

Except they are far from clipping in raw.

[Tim Lookingbill]

Except they are far from clipping in raw.

You and I have a different standard for what a flower should look like clipping or no clipping. There's certainly no accounting for taste.

Iliah, if you aren't going to read my full responses to your quoted statemetns and then answer with questions that show you didn't bother to scroll up to read what you're answering to, I'm certainly am not interested in emailing you on this subject.

I know what I'm talking about because I've had to deal with this issue of optimal exposing for Raw and your articles don't address the two moving targets of varying light intensity and how fast the sensor will react to such rates of change.

[Iliah]

You and I have a different standard for what a flower should look like clipping or no clipping.

I'm not discussing tastes, I did nothing to convert that shot. I'm showing underlaying data, to make a point that JPEG can't be trusted when it comes to exposure evaluation; that is can be extremely misleading. It is also presented in sRGB, because web. If the flower is not clipped you can make it look the way you like. It all starts with avoiding clipping and false overexposure indication that leads to severe underexposure.

[digitaldog]

I've exposed well enough over 1000 Raws, Andrew.

That many? As a regular reader of yours, how many exposed optimally? Got a raw Histogram to share? FWIW Tim, no trick to under or over expose 1000 raws.

[Tim Lookingbill]

I'm not discussing tastes, I did nothing to convert that shot. I'm showing underlaying data, to make a point that JPEG can't be trusted when it comes to exposure evaluation; that is can be extremely misleading. It is also presented in sRGB, because web. If the flower is not clipped you can make it look the way you like. It all starts with avoiding clipping and false overexposure indication that leads to severe underexposure.

And you didn't answer why a magenta flower should look clipped shot under overcast light even shooting Raw where adjusting in post doesn't make it look better. I've encountered this quite a bit to where I have to underexpose just to preserve flower detail far more than what I see in your magenta flower bird bath image.

There's something else going on with sensors that isn't being addressed or solved by camera manufacturers.

[Tim Lookingbill]

That many? As a regular reader of yours, how many exposed optimally? Got a raw Histogram to share? FWIW Tim, no trick to under or over expose 1000 raws.

You're not helping.

[Iliah]

And you didn't answer why a magenta flower should look clipped shot under overcast light even shooting Raw where adjusting in post doesn't make it look better.

It isn't clipped, Tim. When you convert, watch for gamut (a lot of what looks in sRGB as clipped is not clipped), and keep in mind that white balance is exposure (better term is brightness, as exposure can't be corrected after it took place) correction, it makes red and blue channels look more saturated and brighter. Camera recorded those flowers in a normal way, without clipping. The rest is up to conversion process. Incidentally, underexposure doesn't address the issue, it only makes it worse.

There's something else going on with sensors that isn't being addressed or solved by camera manufacturers.

Sorry, Tim, it's like saying "there's something else going with film that ...". The issues are not with sensors. They are with workflow.

[Tim Lookingbill]

It isn't clipped, Tim. When you convert, watch for gamut (a lot of what looks in sRGB as clipped is not clipped), and keep in mind that white balance is exposure (better term is brightness, as exposure can't be corrected after it took place) correction, it makes red and blue channels look more saturated and brighter. Camera recorded those flowers in a normal way, without clipping. The rest is up to conversion process. Incidentally, underexposure doesn't address the issue, it only makes it worse.

The only way to know for sure those flowers aren't clipped is to examine each RGB channel for luminance based detail like say the veins, subtle folds and color detail that isn't just one monochrome version of magenta.

If there's very little luminance and color detail, then it "LOOKS" clipped to me and I toss the image no matter how optimally exposed it is. You don't show this in your demo images including the first yellow flowers which look almost posterized after the Raw adustment.

[digitaldog]

Some do not understand how a color gamut that is too small can cause one channel to clip and these are usually the sRGB users confusing that with exposure. So yeah, the technical facts are once again ignored.

Some understand the technical facts behind photography/imaging and can make images too. Some are on the opposite ends of that ability scale.

[digitaldog]

The only way to know for sure those flowers aren't clipped is to examine each RGB channel for luminance based detail like say the veins, subtle folds and color detail that isn't just one monochrome version of magenta.

Never seen a raw Histogram?

[Iliah]

The only way to know for sure those flowers aren't clipped is to examine each RGB channel

http://s3.amazonaws.com/IliahBorg/_DSC4210.ARW.4Channels.zip

You don't show this in your demo images including the first yellow flowers which look almost posterized after the Raw adustment.

There was no adjustments applied. All as shot.