NYT article on HDR

I don't get it. What am I missing? I was not moved either way. From what I gather on the internet, folks have been creating composites of multiple bracketed exposures in Photoshop for awhile. HDR just automates the process somewhat. HDR seems like a better solution than a stack of very expensive graduated neutral density filters.
 
Perhaps. My only exposure to the process is what I've seen on the web. On the other hand, I have oodles and oodles of the opposite: single exposures suffering from dynamic range that was too high. Somewhere there must be an acceptable middle ground.
 
Yeah, I think that the problem is that most people overdo it, I mean really overdo it.
Have you seen the Hollywood blvd. pic in the article?! Beurk.
 
Unless I am mistaken; part of the problem (or the main problem) with HDR is the fact that there are NO monitors or vid cards out there that can handle the full range.

Therefore, creating such images, currently at least, isn't going to do any good unless you can VIEW said images on a compatible monitor/vid card (of which there are none).

Again, this is just my understanding of it and people can feel free to denounce my statements :D

Dave
 
HDR is very popular in Flickr. The Explorer page (the page that anthologises the most popular photos of the week) is awash with HDR manipulated images. Whatever its merits and demerits people seem to like it. But it does give me the impression that it is an one year gimmick, and that its popularity will diminish when viewers get used to it. Or perhaps it wont and it will be a new kind of "sunset" snapshot: beautiful to look at but not particularly thought-provoking.
 
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Not only are monitors lacking the ability to display the full 32-bit HDR range, so do printers. What photoshop or the photomatix pluggin does is squash (or cherry-pick) that dynamic range, via a curve or some other fancy input parameters... into a 16-bit image. If you're careful with you adjusments you can get some very acceptable, real looking results.. if you abuse the settings, well you get those surreal looking images. I wouldn't write off HDR as flavor of the month, as with all digital (or dark-room) processing techniques, when done tastefully even highly processed images have artistic merit.

I haven't seen any b&w bracketed film exposures processed with HDR. In theory it should work exactly the same as digital capture. Hmm.. could be an interesting experiment.
 
how is hdr different from burning and dodging a print under enlarger, so you'll get there everything from the negative (and scene) while maintaining good local contrast?
 
Here's exactly the type of scene I routinely encounter. Anything I can do to improve the photograph would be a benefit to me. If the HDR feature of Photoshop works, I'll be using it.


52802687.52802687.OakCreekSunset.jpg


Stock photographs were first good photographs.
 
My understanding is that a digital exposure on a modern day SLR has more dynamic range than film, depending on the sensor size. 32-bit-per-channel HDR is a floating point format, it is nearly inifinite in the dynamic range it can represent. I can take 5 or 6 exposures 2 or 3 stops apart, and combine them via HDR to an image that exceeds the range the human eye can even see. Hence the problem with squashing it to a viewable/printable mode.

The details of how floating points are used to reprsent this giant range currently escapes me.. even with a CS degree, I'm sure I can dig up some papers on the painful details.

If you're interested in the technique, at least how I've been doing it:
1) setup my 20d on a tripod,
2) dial the camera into the exposure I belive to be correct
3) take exposure at -2 stops,
4) another at -4 stops (from original)
5) go back to the original exposure +2 stops
6) then another at +4 stops

Only adjusting the shutter speed, messing with the aperture will affect the DOF, this no good for HDR combining. I have gotten good results by hand-holding when auto-bracketing my camera at +/- 2 stops. Your shutter speed has to be pretty quick and you camera has to be super quick at snapping all the exposures, too avoid any hand motion.

As a side note. I don't recommend seeing Miami Vice in general, but from a technical perspective they used digital HD cameras for the explicit purpose of higher dynamic range.. which translates to smaller f-stop, less bokeh, more background details.. while shooting at night.
 
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michael.panoff said:
My understanding is that a digital exposure on a modern day SLR has more dynamic range than film, depending on the sensor size. 32-bit-per-channel HDR is a floating point format, it is nearly inifinite in the dynamic range it can represent. I can take 5 or 6 exposures 2 or 3 stops apart, and combine them via HDR to an image that exceeds the range the human eye can even see. Hence the problem with squashing it to a viewable/printable mode.

The details of how floating points are used to reprsent this giant range currently escapes me.. even with a CS degree, I'm sure I can dig up some papers on the painful details.

If you're interested in the technique, at least how I've been doing it:
1) setup my 20d on a tripod,
2) dial the camera into the exposure I belive to be correct
3) take exposure at -2 stops,
4) another at -4 stops (from original)
5) go back to the original exposure +2 stops
6) then another at +4 stops

Only adjusting the shutter speed, messing with the aperture will affect the DOF, this no good for HDR combining. I have gotten good results by hand-holding when auto-bracketing my camera at +/- 2 stops. Your shutter speed has to be pretty quick and you camera has to be super quick at snapping all the exposures, too avoid any hand motion.
Click to expand...
Not my idea of a good time out with my cameras, but an interesting technique nonetheless.

As a side note. I don't recommend seeing Miami Vice in general, but from a technical perspective they used digital HD cameras for the explicit purpose of higher dynamic range.. which translates to smaller f-stop, less bokeh, more background details.. while shooting at night.
Click to expand...
The New York Times' senior film critic, A. O. Scott, actually had a few nice things to say about the big-screen Miami Vice, the cinematography being merely one aspect (and I'm not yet a fan of digital filmmaking, at least from what I've seen). I might see it just for a hoot, as well as out of digital curiosity.


- Barrett
 
My understanding is that a digital exposure on a modern day SLR has more dynamic range than film, depending on the sensor size.
Click to expand...

As slide film, possibly, but not by much as they are both required to make positives. As negative film, digital is not even close.
 
Digital still cameras actually have less dynamic range than film - with 16 bit depth. HDR allows you to go to 32 bits by combining the two images.

On the other hand, HD Video has a HUGE amount of dynamic range. When I do photoshoots for my company, we usually hire a multimedia company to shoot HD video alongside of the stills that I shoot. It's incredible - the same shots from two different cameras are completely different. HD is usually much more saturated and can handle at least two stops more of contrast.

I second that vote to go see Miami Vice, not only for the technical aspect (Michael Mann also shot Collateral with HD cameras at night), but for the stylistic and creative aspects of his cinematography. Mann's films are always give me new ideas for dramatic lighting and camera angles.
 
SuitePhoto said:
Digital still cameras actually have less dynamic range than film - with 16 bit depth. HDR allows you to go to 32 bits by combining the two images.
Click to expand...

????

Dynamic range is the luminous difference of the scene recorded between the black point and white point. Bit depth is just how many levels that range is divided into. One is not related to the other. Combining two different images is a method of compressing scene contrast to fit in one image file, not for changing the dynamic range of the camera - there is a difference.

The same goes for film. Printing a negative on a piece of paper using dodging, burning, or different contrast indices does not change the density range of the film, nor that of the paper. Those methods simply control the density range of the film to fit the paper.
 
I agree, speaking in RGB terms, there are only 255 points on the scale, no matter what the bit depth is. HDR images have a 'larger' dynamic range because they allow you to combine highlight and shadow details that normally would not be recorded in a single 'normal' exposure.

Bit depth has more to do with flexablity than it does with dynamic range. A 32 bit image will allow for more colors to be used in the image. The image can undergo large adjustments in PS, which would leave holes in the histagram of your standard 8 bit image (manifests itself as 'banding' in the final print). You can apply extreme curves adjustments to a high-bit file, and then down convert the image to 8 bits (which is all your standard off-set press can handle). A 32 bit image that has holes in the histagram (missing colors), will have a nice and smooth histagram after you down convert to 8 bits - or will have nice smooth graduations of color.

Finder said:
????

Dynamic range is the luminous difference of the scene recorded between the black point and white point. Bit depth is just how many levels that range is divided into. One is not related to the other. Combining two different images is a method of compressing scene contrast to fit in one image file, not for changing the dynamic range of the camera - there is a difference.

The same goes for film. Printing a negative on a piece of paper using dodging, burning, or different contrast indices does not change the density range of the film, nor that of the paper. Those methods simply control the density range of the film to fit the paper.
Click to expand...
 
SuitePhoto said:
Digital still cameras actually have less dynamic range than film - with 16 bit depth. HDR allows you to go to 32 bits by combining the two images.

On the other hand, HD Video has a HUGE amount of dynamic range. When I do photoshoots for my company, we usually hire a multimedia company to shoot HD video alongside of the stills that I shoot. It's incredible - the same shots from two different cameras are completely different. HD is usually much more saturated and can handle at least two stops more of contrast.
Click to expand...
Wow, that's really interesting. I wonder what kind of sensors those HD cameras use.

I take back my previous statement about flim vs digital DR, sorta. The top end Canon 1Ds supposedly has somewhere between 11 and 12 stops.. and the fancy Fuji S3 captures 14-bits/channel, which translates to 14 stops. Although this is the very, very top end of the digital SLR market, costing some serious bucks.

What is the dyanmic range of B&W negative film? 12 stops?
 
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