Thoughts - Manual vs Av

[Robin Usagani]

This is what I was trying to tell people. That is not really a good way to do it. What are you shooting? A crow? White Dove? Blue Jay? You are better off using other metering but spot.

Lots of good info here.

When I shot my birds I almost always use Av and spot metering. No, the camera does not simply then get it right. I know from experience to dial in some compensation and this is always backed up by the histogram.

Each shooting situation will be different, however.

 

[clanthar]

Joe, I really dont understand your argument. How do you expect people to use spot metering correctly. Please explain. Where do they point it?

You don't need the Zone System or any modification thereof to use a spot meter. One good thing to do with a spot meter is to measure the diffuse highlight and then measure a shadow where you hope to retain detail and do the math to determine the scene dynamic range. This isn't using the Zone System it's using a spot meter. Once you've measured that dynamic range you're going to have to decide what to do. One option that you don't have is to N- or N+ your sensor development time.

Joe

 

[analog.universe]

You don't have control over development time, but you do have control over the gamma curve when you convert from RAW to JPG. It's not the same math, but the flexibility is still afforded. If you have a system for predictably placing different tones while shooting, you can make your work with the gamma curve that much more effective and straightforward.

 

[Augphoto]

Can't figure out how to quote from my phone, but anyway -

The crow or white birds for me are usually an anomaly. Most of the birds I shot are much more neutral in color. At any rate, experience guides me and I dial in my compensation. If I do get the occasional white bird, guess what, I still compensate.

Maybe there is a quicker way (if that is your point) but this usually works for me.

How would everyone else do it and why?

 

[Augphoto]

Wow! Just realized that there are two different debates going on in this one thread.

 

[analog.universe]

Yes! How to best use your spot meter is a tangent of whether to use your spot meter, is a tangent of how to meter in manual vs. av, is a tangent of whether to use manual or av. :lmao:

 

[clanthar]

You don't have control over development time, but you do have control over the gamma curve when you convert from RAW to JPG. It's not the same math, but the flexibility is still afforded. If you have a system for predictably placing different tones while shooting, you can make your work with the gamma curve that much more effective and straightforward.

No argument there. In fact you have much more control including local control over segments of that gamma curve. So it's really a different practice.

My biggest problem with retaining reference to the Zone System is this:

For a given film there's an ideal lighting contrast range, exposure and development that produces an optimum response from the film. Always make sure you have that lighting contrast range, expose and develop correctly for it and you get the best possible result. No need for any Zone System. This information was well known before the Zone System.

The problem: Ansel is set up in front of the Grand Tetons and the lighting contrast range is wrong. So he goes home with cr*p and he's unhappy. He goes to see his buddy Fred and says, "Fred, you're a techie, what can I do here?" Fred says, "Fix the lighting." Ansel says, "Bleep bleep bleepin' Fred! It's the Grand bleepin' Tetons. I can't fix the lighting." So Fred says, "Well you know how film density increase is non-proportional to development time. How about you get the exposure you need for those shadows and we'll yank the film early from the developer." Ansel says, "Won't that compromise the midtone response?" Fred says, "Yeah, a little but you can always pitch a cap full of potassium bromide into the print developer, hey, right?" Ansel says, "Fred you're a genius!"

And after Ansel passed the Zone System took on a life of it's own. And people forgot Fred's first answer: Fix the lighting. The Zone System was developed as a second best fit to get a usable photo when you couldn't do the best thing and fix the lighting. If you forget that then you may eventually forget to try and get it right first before giving in to a compromise. Like all compormises the Zone System came with a price to pay. It worked but the fim response was not optimal over the tonal range. Is that the practice we want to reference to digital capture?

I understand it's helpful to build on past practice. That's why Photoshop has burning and dodging tools named burning and dodging. Have you noticed that the burning tool in Photoshop won't burn in missing highlights? --works for film. Maybe we should get around to calling it something else.

Joe

P.S. Sorry about the two different discussions all.

 

[Augphoto]

All is good -

 

[analog.universe]

Yes, I agree with your assessment. However, situations still exist where you can't fix the light, (i.e. the Tetons), and a compromise is still better than not getting the shot eh? Pushing the gamma too far away from linear means you get a non-optimal sensor response in certain parts of the tonal range, as it was for film. I still feel that it's better to make these compromises and get the shot. You can't dim the sun, and you can't get a medium that captures 20 stops of range, that hasn't changed with the move from analog to digital. As there was a need to correct for it then, there is still, and the method for dealing with it bears a strong analogy to Ansel's system, so that ends up being a nice way of explaining it.

Of course you always try to get the light right, and of course you want to expose properly, but that's not always possible. These methods exist as a way of dealing with situations where you don't have enough control over the light for an ideal exposure.

With regard to photoshop's dodge and burn tools: whether or not it will burn missing highlights depends on how you've captured your highlight data and how you've adjusted your gamma curve. Lets say you have an image that requires a positive gamma correction in order for the overall tone to be correct... as a result your highlights get compressed and wash out. Provided you do your burning before you drop down to 8-bit, and provided you didn't blow the highlights during capture, that highlight information is still there, it's just compressed at the top of the curve. In this situation the burn tool will effectively expand that information back down. Once it's actually blown, it's gone, but careful capture and manipulation of gamma allow you to avoid that.

 

[clanthar]

Yes, I agree with your assessment. However, situations still exist where you can't fix the light, (i.e. the Tetons), and a compromise is still better than not getting the shot eh? Pushing the gamma too far away from linear means you get a non-optimal sensor response in certain parts of the tonal range, as it was for film. I still feel that it's better to make these compromises and get the shot. You can't dim the sun, and you can't get a medium that captures 20 stops of range, that hasn't changed with the move from analog to digital. As there was a need to correct for it then, there is still, and the method for dealing with it bears a strong analogy to Ansel's system, so that ends up being a nice way of explaining it.

I have a fairly strong studio background where you can always fix the light. And it's real important to me that everyone understand that that's the correct answer and only when that's not possible do you move on to a compromise. I do have this bit of a knee-jerk reaction to the Zone System because of that. I've had way to many occasions to watch a "zone systemer" calculating N- or N+ development times for a still life shot in a studio.

When you can't fix the lighting and you still think it's possible to get the shot with some skillful PP -- by all means you should proceed. I do not however see an analogy between the Zone System and how I would do that today. If the lighting can't be fixed then yes it's still a compromise. But right from the start I would meter and expose differently than I would if applying the Zone System to film. There's some huge differences. In the Zone System you could use an exposure that would push your highlights as much as two stops over normal. I expose my digital sensor to place my diffuse highlight. Any additional exposure is a disaster. The recovery slider in ACR only works to a point. I'm already exposing to the point where I have to apply it. I'm not going to expose beyond the point where it will do any good in order to place my shadows on III. In fact I do the opposite of what the Zone System taught. "Expose for the shadows and develop for the highlights." Is NOT what you want to do with digital. It's the opposite of what you want to do with digital. The digital mantra should be ALWAYS expose to place the diffuse highlight -- no analogy there for me.

Joe

 

[Trever1t]

Subscribed. Some really good info to absorb here. Thank you.

 

[clanthar]

You don't have control over development time, but you do have control over the gamma curve when you convert from RAW to JPG. It's not the same math, but the flexibility is still afforded. If you have a system for predictably placing different tones while shooting, you can make your work with the gamma curve that much more effective and straightforward.

No argument there. In fact you have much more control including local control over segments of that gamma curve. So it's really a different practice.

I had wanted to expand on this but it was too late last night, so here's an example today:

That's the RAW capture in ACR with no adjustments of any kind -- As Shot.

Metering: I pointed the camera straight up at the grey clouds over my head, pressed the AE lock, recomposed and took the shot. Spot metering, matrix metering, whatever metering would have all been the same. The camera was set to P mode and it stayed there. The ISO was set to lowest value, the WB was on auto and no exp. comp.

I got what I wanted: The one single MOST CRITICAL THING; I placed the diffuse highlight without blowing it. That highlight is the beginning of a sunset sky in the upper left. How did I know to meter off the clouds? Been there done that.

The scene is backlit. Needless to say the lighting needs to be fixed. I couldn't fix it. Therefore I applied the Joe System -- PLACE THE DIFFUSE HIGHLIGHT and get a RAW capture.

A little time spent in ACR and a 16 bit RGB transfer to Photoshop gave me this finished photo:

Back to the top of this post and gamma curves: I didn't just apply an adjusted the gamma curve to the RAW capture. I applied one gamma curve to the sky and another gamma curve to the dam and tailwaters and another gamma curve to the lock wall and water and another gamma curve to the boat, etc..

Digital capture opens up a whole new world of possibilities. Film technology no matter how it's manipulated simply couldn't have done this.

Joe

 

[Robin Usagani]

Joe, what you did is practically what I called "zone system". You pointed at something that you believe should be at 0 and lock the exposure. What i didnt recommend was for someone to use spot metering without AE lock and just snap happy. You could be pointing at the black, the white, shiney object, light source etc. You could probably also point it at the red stripe and set your EC to -1, or the white paint and set your EC to +1.

You know what I wish they have? An Av button that you can press while on manual. It will quickly set the shutter based on the aperture and ISO you have and you can adjust it like manual setting.

 

[Hardrock]

For birding and outside daytime sports I will usually use Av with spot metering. While using Av I will check the histogram and the image to adjust the exposure compensation. For almost everything else its M. I never use Tv or any of the other settings. I use spot metering due to I mostly use the center focus dot for those and the spot meter is reading off of the center. However for everything else thats manual I use evaluative metering set the exposure to 0 and adjust from there. Hope this helps and like others have said lots of great info here!

 

[kirbym2]

Great thread, great links, great info! Appreciate all of the insight everyone! Also appreciate not being referred to other threads (save for one exception) - I am always interested in different views, and seeing where a thread can go. I got a lot more out of this than my original question of Manual vs Av.

I know it can be a pain to re-explain - but honestly, I think the variety of explanations, insights, etc. are what made this what it became.

Thanks all!