Single Exposure HDR?

[spacefuzz]

why the hostility?

No hostility. I just want to see it done.

Ok cool. Hard to tell tone on the internets.

Just like I've asked several members to tonemap a single image with digital black (0:0:0) and white (255:255;255) and magically produce the details.

Well you could pump it through photomatix and make it look so garish you dont notice the blown highlights....but you cant get them back.

Dont worry that wasnt what I was trying to say. I was saying in circumstances when you can use a GND, you can just compress the dynamic range using that so you dont have any blown highlights or shadows in a single exposure (whereas without the filter you would). Then normal processing commences.

 

[clanthar]

I think HDR should refer to a type of photo and not a methodology. If you have a functional method that permits you to capture a scene or create a photo that contains a greater than normal dynamic range then I think you can call it HDR. My film scanner has a 48 bit setting that allows it to scan a film original in one pass and record more tonal information than the "normal" setting. Silverfast, the company that sells the software, calls that setting HDR. They were using the term HDR for at least a decade before Photomatix existed.

30 years ago in the darkroom we would take a Kodachrome original (you'd be amazed how much is really there) and place it in a special negative carrier with a piece of photochromic glass. Using a small speedlite we'd flash the neg carrier from the film side and build up a functional highlight mask in the glass (think GND that would indeed work for the bike). We made HDR prints that way.

An HDR photo exhibits an extended tone range beyond what is normally possible and can be achieved via a multitude of methods including a combination of methods.

Joe

 

[spacefuzz]

30 years ago in the darkroom we would take a Kodachrome original (you'd be amazed how much is really there) and place it in a special negative carrier with a piece of photochromic glass. Using a small speedlite we'd flash the neg carrier from the film side and build up a functional highlight mask in the glass (think GND that would indeed work for the bike). We made HDR prints that way.

impressive!

 

[Bynx]

A GND is useless for creating an HDR image for all situations EXCEPT ONE -- if you are shooting a scene where you can exactly cover the brightest area with the GND thus reducing the exposure necessary and matching the camera settings for the darker, correct exposure for the rest of the scene. (50% open sky 50% earth). The motorcycle example has highlights throughout the image. How does a GND cover that situation? If there is hostility being shown spacefuzz its due to stubborn ignorance. An HDR is more than just cutting down the exposure on the high end, its also increasing the exposure on the low end. Now tell us how your GND is going to cover that?

 

[spacefuzz]

A GND is useless for creating an HDR image for all situations EXCEPT ONE -- if you are shooting a scene where you can exactly cover the brightest area with the GND thus reducing the exposure necessary and matching the camera settings for the darker, correct exposure for the rest of the scene. (50% open sky 50% earth). The motorcycle example has highlights throughout the image. How does a GND cover that situation? If there is hostility being shown spacefuzz its due to stubborn ignorance. An HDR is more than just cutting down the exposure on the high end, its also increasing the exposure on the low end. Now tell us how your GND is going to cover that?

I did tell you that, but I guess you were too high on your horse to actually read my posts

 

[clanthar]

A GND is useless for creating an HDR image for all situations EXCEPT ONE -- if you are shooting a scene where you can exactly cover the brightest area with the GND thus reducing the exposure necessary and matching the camera settings for the darker, correct exposure for the rest of the scene. (50% open sky 50% earth). The motorcycle example has highlights throughout the image. How does a GND cover that situation? If there is hostility being shown spacefuzz its due to stubborn ignorance. An HDR is more than just cutting down the exposure on the high end, its also increasing the exposure on the low end. Now tell us how your GND is going to cover that?

You're correct that a GND filter only works for landscape photos with a fairly straight horizon. It needn't be 50/50 sky/earth. Most GND filter rigs allow the filter to both rotate and move up and down. So a GND filter would also work for 15/85 sky/earth or 85/15 sky/earth or anything else in between.

As for increasing low end exposure, once the gap between the high and low ends is sufficiently compressed by the filter the exposure can be increased to include additional shadow detail -- kind of the point.

It's a limited technique and of course it wouldn't work on the bike. Just like multiple exposures wouldn't work on a flock of migrating birds. That's why it's nice that we have multiple techniques to achieve the same result when one or another variable throws in a wrench.

Joe

 

[Compaq]

Just because a scene includes both black and white pixels (in the best possible single exposure) doesn't mean that we need to bracket exposures and merge. Having black and white ares is beneficial. It adds contrast. I'm sure the motor cycle shot could work fine as a single exposure and some editing.

Some people believe, me included, that some tone mapping can make a photo "pop". That is not to say it's needed to cover the dynamic range in the scene. Wikipedia defines HDRI as a set of techniques that can be used to allow a greater dynamic range to be displayed in the final photo. Whether that's using GND filters (which affects highlights directly and shadows in directly (allows us to expose for shadows)) or adding exposures in different layers in PS and masking in or tone mapping in Photomatix or other SW, doesn't really matter. At the end of the day whatever technique you use to allow for a greater dynamic range than your sensor can capture could be looked on as high dynamic range imaging.

 

[Bynx]

Hey folks, there are always more than one way to skin the cat. And that goes to covering the range in a given scene. A GND is so limiting why even consider it? The technique of doing multiple exposures is so simple for all HDR situations why fight it and come up with some other very less effective way to cover a limited specific situation? Spacefuzz I think the definition for you is obtuse. But thats ok. Maybe some other people will understand whats being said and come out of this with a better understanding of what exactly HDR covering is and how to do it properly.

 

[480sparky]

So, let's hear all the possible solutions for this:

 

[Compaq]

Well, obviously, you cut holes in your ND filter to fit the windows, duh!

 

[clanthar]

Hey folks, there are always more than one way to skin the cat. And that goes to covering the range in a given scene. A GND is so limiting why even consider it?

Because it works when it works. Why exclude it?

The technique of doing multiple exposures is so simple for all HDR situations why fight it and come up with some other very less effective way to cover a limited specific situation? Spacefuzz I think the definition for you is obtuse. But thats ok. Maybe some other people will understand whats being said and come out of this with a better understanding of what exactly HDR covering is and how to do it properly.

It's October next week. The pelicans will be here soon. They migrate through in the tens of thousands -- in about 15 days. I try and get some shots but the weather doesn't always cooperate and the birds certainly don't. You have to get out on the river to get anything.

Had a bad day a couple years ago with really bad weather. Still I was there. Here's a straight out of the camera JPEG:

That overcast sky is of course a backlight and even though it's not sunny, backlight is high dynamic range. The opposite shore has green foliage and some trees starting to turn color.

Here's the same photo processed from the RAW file:

That's an HDR photo. The color and tone in the opposite shore really was there and a 16 bit RAW capture brought it home.

Your technique would be to set up a tripod in a moving jon boat -- seriously fun. Then take how many multiple exposures?

Given the circumstances we do what works. Why limit yourself? If a GND filter will work, I'll use one. You won't? A GND filter works when you have a moving subject -- multiple exposures doesn't. I've also used the multiple exposure HDR method when appropriate. I'll do whatever I can to capture a better photo.

Joe

P.S. I see no reason why spacefuzz's GND filter shouldn't be included as one of many techniques to approach HDR.

 

[spacefuzz]

Hey folks, there are always more than one way to skin the cat. And that goes to covering the range in a given scene. A GND is so limiting why even consider it? The technique of doing multiple exposures is so simple for all HDR situations why fight it and come up with some other very less effective way to cover a limited specific situation? Spacefuzz I think the definition for you is obtuse. But thats ok. Maybe some other people will understand whats being said and come out of this with a better understanding of what exactly HDR covering is and how to do it properly.

Heheh. I'm not obtuse, I just like trying to enlighten people when they are limiting themselves due to their own stubborness. Why hamstring your tool kit? GNDs are not less effective in all situations, just some (and it really depends what you shoot, I spend a lot of time shooting seascapes so GNDs work very very well. But like I said before I dont bring them to the mountains or when I'm shooting architechture). Its great to get everything in one shot, gives me a better indication of what the final image will look like and has the added bonus of allowing me to spend less time in post. But I know some poeple love post, so again it depends.

If you want to be obtuse Bynx thats fine, its your photography....but dont insult me just because I do things a different (and equally valid) way
(and I checked out your flickr, I understand why you dont use GNDs in your HDR shots but if you ever travel to the coast keep an open mind

 

[spacefuzz]

So, let's hear all the possible solutions for this:

In camera GND based on luminosity!

Adjustable neutral density filter ... - Google Patents

Honestly, I cant wait for something like this..... (although then everyone will have perfect images.....and there will be even more pro's!)

But sparky if I had to shoot that today? Definitely bracket and merge.

 

[480sparky]

......... Here's a straight out of the camera JPEG:

...........

Here's the same photo processed from the RAW file:

............

 

[Bynx]

A GND will probably work fine as long as the highlight area all falls within the ND area. Its not that it works for most of the time. It will work for a select few times. As I said more than one way to skin a cat and Photomatix isnt the only way to achieve HDR images. Seas where you have uninterrupted sky will be good for your GND. But the concept of using multiple exposures grew out of broader range of lighting situations. Now without jumping on me and what Im saying, how about just looking at the images posted by sparky and tell me how you would handle them with your GND. Under an extremely limited lighting situation where there is no dynamic range a good exposure can be had with a single shot. But it cant be done, for example, with any of those images posted by Sparky. If it can, please enlighten us.
Clanthars bird shot doesnt have a great dynamic range. Its pretty flat actually. So simply brightening it up globally produces the final image. Not rocket science there. Under similar situation where there is fast movement to capture I would do the same....shoot raw and tone map from the raw info. And clanthar, I didnt say GND wouldnt work at all. I did say it would work under a single ideal situation.