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Hello a1ex,

Just a note, in case you accept my proposition and actually implement the sunny 16 rule into ML. This relates to the bottom two rows of the Rollieflex diagram dfort was kind enough to post earlier. Those are modifiers to all the Ev's in the table, both for the time of day/year as well as for the weather.

Here you go, and dfort please correct me if I'm wrong. If the sun is high in the sky, so that your shadow is shorter than you are then you're good with the Ev from the table. If your shadow is taller than you are, you overexpose by one stop. If your shadow is also more than twice taller than you are, you overexpose by one more stop. If shadows of objects in direct sunlight are hazy, then you overexpose by one more stop. 

Many people didn't do that, thinking that because a subject is in a skylit shade then the exposure was always the same. They were wrong, as a skylit shade is much darker at sunset than it is at noon. Still, the guys in the labs worked harder on their negatives and produced acceptable prints nonetheless :-)

Cheers

Hello,

I did the experiment, and the results are in. HYG: https://www.dropbox.com/sh/e6jsdvp9x6wn66z/AACPd4sel6C1PhNhfOPXbjZ_a?dl=0

If you're not familiar with the target, here are the specs: https://www.bartneck.de/2017/10/24/patch-color-definitions-for-datacolor-spydercheckr-48/

I used a collapsible grey target for correct exposure and white balance. The 7 photos run from correct exposure -3Ev through correct exposure +3Ev. Other than adjust their exposure, nothing was done in post.

As you can see, between +2Ev and -2Ev nothing interesting happens, and only few colours shifted at -3Ev, I can see only 5 patches slightly shifted. At +3Ev too many colours were damaged, most notably the lighter skin tones in column C, and sky blue and foliage green in column A.

I shall repeat the experiment shortly for the following reasons:
- I would like an AETTR exposure too, didn't think of that this time around.
- I will use ML Advanced Bracketing to go from correct exposure +/-5Ev.
- Anything else you might like to ask for :-)

Cordially

Now when I think about it, perhaps AETTRight needs to be complemented with AETTLeft, but that would be another thread.

But isn't that basically how you would bracket shots to begin with. Except that one wouldn't have to guess where the brightest of the highlights and darkest of the shadows are.

Or maybe it would be enough for ML to print the SBR somewhere on the display. Or perhaps start with AETTR and then overexpose by 1Ev for as many shots as the SBR requires. I need to think about it before I bother you with yet another thread.

Hello,

I shoot exclusively RAW, AND exclusively in manual mode.

Raw zebras are yet another way to interpret the reading of the same meter, with the same reflected light complications. It is that meter that I am trying to eliminate from the workflow. Describing a dozen other ways to use the same reflected light meter is totally irrelevant from the point of view of my request, because my request is just about CIRCUMVENTING that meter, IGNORING it totally.

And ettr, whether auto or manual with zebras or otherwise, is by definition NOT correct exposure. Correct exposure is when white is captured white, black is captured black, and gray is captured gray. ETTR is about capturing the brightest as white, whether that brightest was white, black, or anything in between.

And from the heat of the moment viewpoint, you change those sunny 16 settings only when the light changes. You might not touch them for hours if the weather permits. And trust me, if in the heat of the moment you meter every shot differently, you are missing exposure more often than not, and colour accuracy most probably suffers too. We'll be sure when I post my experiment details tomorrow.

Thanks

Dfort and a1ex, I cannot thank you enough.

Dfort got it right almost allll the way. Those diagrams are exactly what I had in mind when I posted the request. There are apps now that do the job of those diagrams, 'Photo Friend' is one of them that is available for iOS as well as android. And those apps encompass a much wider selection of lighting conditions than the Rollieflex diagram did.

And a1ex had me plan to at last run an experiment I kept putting off, details to follow. I will run the experiment tomorrow, post the results, and I hope you will like it.

I was aware ML displayed the Bv associated with the selected Tv, Av, and Sv, as well as their correct APEX values. My request is to allow the user to SPECIFY a Bv from a drop down menu or a list, and then ML would select a corresponding valid Tv, Av, and Sv combination. The user could then, thanks to Exposure Lock, change those settings to a more desirable equivalent exposure.

That we specify it in Bv, or Ev, would be of little help. It's the description of the lighting conditions that matters. And if fredparker.com author asks $3,500 for a 'license' to use his wording, then we should get those descriptions from elsewhere for free, like from wikipedia, or https://www.thephoblographer.com/2016/04/16/the-ultimate-guide-to-the-sunny-16-rule-part-2/ , or https://www.slrlounge.com/photography-essentials-the-sunny-16-rule/ , or a dozen other sources. I would also suggest those descriptions be kept in a user editable text file or csv, for every user to modify to his/her liking.

As for my experiment, it's an investigation on the effect of over/underexposure on colour accuracy. I've stumbled upon this post https://www.blog.jimdoty.com/?p=10138 a few months ago, and I have since planned to check it out for myself. I would like to learn just how far can I safely over/underexpose before colour is permanently damaged. But ever since I've read that post, I have been keen on nailing the correct exposure in camera. For correct exposure I reverted to good old Sunny 16 and co., and they have been as helpful as ever.

On exposure, IMHO, AETTR is a great feature. Rather than have the blunt auto exposure averaging the scene brightness and placing that average at say -4.0EV from highlights clipping, AETTR takes the 99.9th percentile and places it at -0.0EV from clipping. A refined highlight priority if you like. Still, it is not infallible, as specular highlights for example are sure to sway exposure way into underexposure. Spot metering is also a great feature. Still, like with all reflected light metering you need to account for the subject tone, colour, and texture. IF you spot an 18% gray card, AND your white balance is correct, only then would you get a reading comparable to that of an incident light meter. As useful as they are, I don't see how could AETTR or Spot Metering help with a bird in flight for example, or fireworks, or a moonlit beach...etc. Trust me, for those situations and more, Sunny 16 and co. save the day.

So, A1ex, I suggest we do NOT engage the meter at all. We ignore it and we SELECT the lighting conditions from a list. Our eyes become the meter.

Cordially

Dear Audionut,

Camera meters measure REFLECTED light, which Canon exploits to make available aperture priority, shutter priority, program mode...etc. ML too exploits the same meter to provide AETTR, zebras, Auto exposure...etc. All cool and useful stuff that I really appreciate and enjoy, thank you. However reflected light meters fail photographers every now and again, like when the subject is black, or white, or when you use polarising filters...etc.

INCIDENT light on the other hand is more robust, with high repeatability. You stick your incident light meter next to your subject's face, point it to the camera position, and take a reading. This might not be convenient at times, like when the subject is way too far, so photographers have relied for decades on the sunny 16+ guidelines. You just look around and notice that the subject is in sky lit shade, then you lookup those conditions on a piece of paper, et voila, f/4 @ 1/125 for your ISO100.

Now my suggestion was about that piece of paper. That piece of paper, the one with lighting conditions and camera settings, evolved into quite a few mobile apps and online exposure calculators, so evidently not peculiar from a photography perspective. I hope you agree that that same useful information can be incorporated into ML, with the logical extra step of ML setting the exposure parameters to match the manually selected lighting condition.

Lastly, I would very much appreciate it if you were to observe the forum rules, and either stick to the subject of the discussion or refrain from responding. I'm honestly not sure about peculiar, nor do I see where goal posts came from, let alone the prior irrelevant response. Indeed, I'm surprised that the differences between reflected and incident light metering need to be clarified at all on a photography related forum.

Please let me know if it could be done, and thanks a lot in anticipation.

Hello Audionut,

This is also auto exposure, where the camera meter measures reflected light and acts accordingly. I would like to decide on the incident light, and manually let the camera know that it's a heavy overcast scene, so that it sets the appropriate shutter/aperture/ISO to achieve an EV of 12.

Hello,

Thanks again for making ML a reality, I really enjoy it a lot

I suggest a way to assign focusing to one of the dials on the camera, probably temporarily to revert to its original function after focusing is done. I hope this works both in LV as well as in normal shooting.

Sometimes you have to improve on the camera's autofocus with just a tiny nudge to the focusing ring. But of course not all lenses allow you to do that while in autofocus mode. And for other lenses the focusing ring throw is just too short to achieve critical focus manually. With such lenses even Focus Peaking doesn't help, as the stripes move all over the place the moment you touch the focusing ring. I am sure there are more use cases where such a feature can save the day, those are just the times when I wished for a different way to focus.

This would also work very well with Trap Focus. Now, everytime I have tried Trap Focus I got out of focus photos, because by the time the camera decides to take the shot I would have already manually changed the focus!!! Does that happen to you too, or is it just me?

Regards

Hello Schulz,

Thank you for your prompt response.

ETTR and zebra overlays work perfectly well, on reflected light. They try to fit the measured signal as best as possible given the sensor's characteristics. Sunny 16 et al. on the other hand work on incident light, with little regard to the sensor or otherwise. To be sure, both metering methods have their pros and cons. In this particular case, a sunny 16 exposure would require more noise reduction, while ETTR calls for exposure adjustment in post processing.

Perhaps, if one has the time, a more 'accurate' approach would be a sunny 16 exposure for reference, AND an ETTR exposure for raw cleanliness and minimal clipping. That is surely something I would like to test in the near future.

What do you think?

Hello,

First, I would like to thank all ML contributors for their time and effort. I have enjoyed ML on my 60d, and currently on my 6d, and really appreciate the extra skills it teaches my cameras. Thank you.

Now, my simple proposition might go against ML highly technical fiber, but I'm sure it's feasible so please bear with me. I suggest ML allows the user to choose the lighting condition, and then set the appropriate SS/A/ISO accordingly, observing the relevant limits of the various settings. The user can then engage Exposure Lock and manipulate this 'correct' exposure setting to achieve a more desirable depth of field, or a particular level of noise, or even override the settings altogether for high/low key effect... etc.

The reason I'm asking is that I have used the sunny 16 rule and its close siblings for quite a while, and the results are never further than one half of a stop from where I expect them. And, while everybody can easily memorise and apply the sunny 16 rule -1/-2 stops, the full tables for exposure values with the full description of each lighting condition, those tables are not that easy to commit to memory. For that step I refer to an app on my mobile, and then copy the suggested numbers in my camera. It would be great if ML could take over the app role, as well as ensure the settings are copied accurately :-)

I'm sure you're all aware that many versions of those tables are widely available in books and over the web, and hope that if you decide to implement this feature, please keep the lighting conditions descriptions in a text file that the user can modify/translate... Perhaps not everyone likes the longer descriptions that I prefer, and they should have a way to modify them to their liking.

Please let me know what you think.

Regards