One file - HDR possible?

[RaymondC]

Hi, I have Photomatix and Redynamic (PS Plugin). When I choose one image and do

a HDR I get v grainy images - off scanned film (slow ISO). Is this technique

possible?

 

 

Also is it possible with digital SLR? Or would I get v grainy images?

 

 

Sometime I am walking around without a tripod, and multiple images are not

possible or that some places inside and outside prohibit tripods.

 

 

Thx.

[bryantan]

With a single image, all the dynamic range that exists is already present. Feeding different files from the same RAW file or film scan (assuming you captured the entire dynamic range on the film in one scan) into an HDR program will give you the appearance of a greater dynamic range, but the results are unlikely to look realistic. Burning/dodging or applying curves adjustments selectively to certain portions of the image achieves pretty much the same thing.

[peter_daalder]

Some of my (single shot) images are approaching <a href="http://www.photo.net/photo/7054687"> a kind of HDR effect. </a> Most of the work is done using a combination of RAW converter settings and a range PS CS2 adjustments, including dodging and burning.<br>I know that this doesn't answer your question, but as Bryan pointed out, all the dynamic range is present in a single exposure image. It is just a matter of extracting the maximum amount out of it. <br>Obviously, it doesn't work with all single shots...

[Ed_Ingold]

It is pointless (and futile, as you see) to stack up copies of one image in an HDR file.

 

If the scanner is set up properly, the histogram will be tapered, not jammed, at the ends of the scale. There's nothing more you can do. When in doubt, simply disable all the adjustment controls or scan in RAW mode. Turn off all real-time processing except Digital ICE.

 

To get the most complete (and generic) information at a time, scan the film as RAW files (Nikon NEF, Silverfast HDR, etc). Raw scans capture everything the scanner can see, but must be processed later using the scanning software. The advantage is that you can try different settings without repeating the scan itself.

[robert_fisher4]

There are a couple reasons why there's less noise in a muti-exposure, tonemapped HDR image. First, by increasing exposure in the shadow areas, you're automatically reducing noise in those areas to begin with. Then, when the images are merged, the averaging algorithms reduce noise in the entire image as well. It doesn't work with a single image, even tweaked to give different exposure results because all you're doing is brightening the shot which simply makes the noise in the shot more evident. The averaging that takes place during the HDR merge will help some, but not a lot.

 

Using just a single image and tonemapping it is going to show more noise, again, because all you're doing is brightening shadow areas and making the noise that's there more evident.

 

Could you do it with scanned film? Sure, but you'd need multiple shots at different exposure settings and you'd have to scan those. It's still not going to work quite as well as using RAW files from a digital camera because the scans you use will be cooked image files (TIFF, JPEG, etc) which means that you've already locked in certain results which reduces the amount of flexibility you have in the HDR process.

 

You can do it with a digital camera, which is what most people doing HDR do. For best results you want to shoot in RAW mode and use those RAW files in the HDR software. The alignment functions in the various HDR programs work somewhat well to not well at all. Handholding isn't ideal but if you've got a camera with a fast burst rate and can hold pretty steady, you can knock off at least 3 shots in pretty short order. There are some cameras now that allow for 5 shot bracket bursts and a couple that I think allow for even more but most are three. Personally, I like Dynamic Photo HDR for its manual alignment capability.

[beartooth1]

There are some images in my port that were done with the Redynamic Plugin in PP X2 then further Processed in CPP X3. All done with RAW files. Take a look if you like. This might give you some idea of the end result.

[mendel_leisk]

The purists will say no, but, you *can* milk extra range from a single exposure, and it is a lot more convenient and seamless compared to dealing with tripods, multiple exposures, issues of subjects moving. It's the only approach that is possible with transitory shots.

 

Working with DSLR files with the latest Adobe Camera Raw, the "fill light" slider is quite effective. Just allowing ACR to do what it can to retain higlights with it's "auto" adjustments, and then raising "fill light" to open the shadows (which tend to get pushed down by the "auto" process), and then raising "contrast" about the same amount as "fill light" works for me.

[matt_mcelroy1]

You can absolutley make an HDR image out of a single RAW file. One reason that I can think of that you would want to do this is to tonemap the image to give it a bit of a more artistic look.

 

Use your RAW software to create 3 jpegs of the original file, adjust the exposure settings as -1,0,+1 EV.

 

When using Photomatix you can combine the 3 images and then tonemap to condense the dynamic range.

[emre]

Matt: Tone mapping is not HDR. HDR by definition means more dynamic range than can be captured in a single shot.