Thoughts - Manual vs Av

[ann]

Have been following this thread with interest (at least in this one there is one intelligent discusion )
I have been using pure manual metering for 64 years, that is how i was taught and the only thing available at the time, so it is second nature to my process. Am more than familar with the Zone System , etc. And have also been there , done that with metering off gray skies, green grass, blue jeans, the palm of your hand etc.

I have also used other modes, as what ever it takes to get the shot is the best method .

Anyway, I understand all forms of metering, etc. but what caught my interest was clanthar and your use of gamma curves in raw. PS is not second nature for me, (think lower on the list). I plan on googling that technique, but do you have any links that would direction me to the site that is corrective. In otherwords people who can talk the talk and walk the talk. I do understand about using curves, but the question has more to do with using it in speicfic locations on the image. Would that be with the use of layers, or curves in each RGB channels?

Am checking on the Chambrige site, but so far they are just discussing standard curves.

 

[KmH]

You can select various parts of the image, using the selection tool of choice. You can save each selection too, and you can invoke the inverse of a selection.
With the selection active you can click on the 'make a new layer' icon at the bottom of the layers pallet, and the new layer will have that selection as a mask. You can then use any of the filters and they will only affect the selection you made. Or you can make an adjustment layer from that mask selection layer, and the adjustment will only effect what you selected.

 

[ann]

Thanks Keith, gives me a great starting point to consider, practice and think about

 

[clanthar]

Anyway, I understand all forms of metering, etc. but what caught my interest was clanthar and your use of gamma curves in raw......Would that be with the use of layers, or curves in each RGB channels?

Just got back from my afternoon walk.

Keith got you started with a simple description. Let me see if I can flesh that out some. First terminology; gamma curve is just fancy language for contrast. Think of it as #1 filter, #2 filter, #3 filter, etc.

So right after ranting about a weak analogy (somewhat my hang up -- I apologize) let's start with an analogy. You're in the darkroom and you've got a negative of a high contrast scene. You use a #2 filter and get a normal density print with good contrast. But the highlights are a white hole in your print. You look at the negative and there's plenty of detail there in the highlights. They'll probably print with a lower grade filter. OK -- you make the print with a #0 filter and sure enough some slight burning and the highlights are there -- but the midtone contrast sucks now.

You look at the print and notice that you'd like some additional shadow detail. There's at least a stop more detail down there if you dodge it out. But oops, the contrast in the dodged shadows is even worse. If only you could burn in the highlights through a #0 filter, print the midtones through a #2 filter and dodge the shadows through a #3 filter. You can! I've been there. That's why I use Photoshop now.

Next step: You have a 14 bit RAW capture. Think back about that extra stop of detail you could dodge out of that negative and add on at least 4 more stops of usable data. Ansel is peein' his pants at this point. The problem is it's more data than you can possibly use. Back to that darkroom print: white paper isn't going to get whiter and Dmax isn't going to get darker. You've got no room for all that data. When you switched out to that #0 filter the print got flat. You were trying to squeeze more data into a fixed space. So a modern RAW capture has more data than a print or even your display can hold without squeezing it to the point of total flat yuck.

Apply some kind of software algorithm to the data to try and normalize contrast and you'll get the camera JPEG -- crash and burn.

So here's where Keith's comment comes in. Before you let go of any of that data you've got to cheat and apply "different filters" (gamma curves) to different sections of the photo. Any time you raise contrast you are losing data so you've got to go carefully. I use layers and masks to apply changes to different sections of the photo locally. I will also paint right over a section of the photo to locally change contrast. And while we're at it of course you can locally change density and color as well.

Specifically: The first photo below is a very early stage of processing the image from my previous example. The second photo shows a first pass at modifying the sky. I inset the Layers palette so you can see I have two dupes of the original with masks for the sky and in this case blending modes to achieve the change I want. It's a fair amount of work but it's worth it to think of Ansel peein' his pants if he could see it.

Joe

EDIT: Get the light right in the first place and you don't have to do this stuff!

 

[The_Traveler]

But this must be in PS proper not ACR, yes?

 

[clanthar]

But this must be in PS proper not ACR, yes?

Absolutely. ACR and/or Lightroom can't do this and neither can GIMP because GIMP is 8 bit limited.

Joe

 

[The_Traveler]

But this must be in PS proper not ACR, yes?

Absolutely. ACR and/or Lightroom can't do this and neither can GIMP because GIMP is 8 bit limited.

Joe

There is a program called Perfect Layers that purports to be well hooked into LR and that will allow layering.
Since I don't need it, I haven't investigated byt for those who have only LR this may be a low cost avenue.

 

[ann]

Thanks, basically it was kind of you do sit down and write out all that information and you would have no way to know I understand the whole comparsion you have made, and certainly understand the last section , which is what i was looking for.

I am not a serious PS user and was not sure how you made all those changes to specific areas.

Have yet to figure out how to make the light do my bidding, but i am not alone there

 

[clanthar]

Thanks, basically it was kind of you do sit down and write out all that information and you would have no way to know I understand the whole comparsion you have made, and certainly understand the last section , which is what i was looking for.

I am not a serious PS user and was not sure how you made all those changes to specific areas.

Have yet to figure out how to make the light do my bidding, but i am not alone there

Hi,

I've seen enough of your posts to know you've taught and have for a long time -- so the darkroom analogy.

I have also taught for a long time; I was teaching the Zone System in a college class 30 years ago. The number 1 thing my students hear from me is this: Amateurs look through their cameras and see things, photographers look through their cameras and see how things are lit. See the light!

I'm retired now and getting lazier by the minute. I know I can do that kind of processing when the light is adverse but more often than not I never take the camera out of the case. I look at the scene, I "visualize" 45 minutes in Photoshop and I move on.

Joe

 

[ann]

Ahmen on that.

Yep, I have been doing this a long time, and altho, i no longer teach a Zone system class (not enough serious interested students these days) I harp on the only thing we have "light and form" that is what a photographer has and you have to learn how to use the light to your advantage, which includes moving your feet. Sometimes to walk on by.

Also my training and education is "get as much right in camera as possible", makes the darkroom work easier and more fun and for me, I want to use PS to be creative, not "fix something". My PS skills are pretty basic as I have to be in a certain mind frame to sit down and work at the computer and you give far more time than I
That is why what you did with the image caught my attention, as I would use curves for the contrast, but I wouldn"t think about applying that curve only to a specific area.

I am suppose to be retired, but............still love teaching so I suppose I will continue until I am off to the body farm. However, I know what you mean about getting lazier, my interest is highly reflective of how far I have to walk away from the car.

Take care

Ann