HDR techniques. When do we need those?

alaios

Hi all,
few newbie questions sometimes pop out in mind...
A.when do you think is the right time to HDR and
B.which are the cases that HDR would return worse results compared to a "normal" shot?
C. Is it possible to handheld HDR Shots and if yes what are your recommendation regarding the needed shutter speeds.

I would like to thank you in advance for your replies

Regards
Alex

pathfinder

Hi ALex,

There is no "right" time to do HDR, but any scene with a large dynamic range is a potential scene for HDR imagery. If you think you might want/need to use HDR, shoot a bracketed exposure, photons and megabytes are cheep these days. If you decide later you do not need HDR< just delete the extra files, they cost you nothing but a bit of temporary storage. SOme folks I know and respect always capture scenes with bracketed exposures, at least for landscapes and similar images. HDR is not really that useful for sports shooting and high speed brightly lit scenes.

When is HDR worse than a single file?? Depends entirely on how skillful you are with HDR processing. The key is that you have all the shades of tone you need for your image, and this depends entirely on how your image is rendered, constructed, depicted. You can always delete your over and under exposed frames, and just use your "properly exposed" frame is that will meet your needs.

Is is possible to handhold HDR shots? Yes, I do it all frequently. I prefer to have the longest exposure shutter speed shorter than 1/60th of a second, but am not a fanatic about this. With modern high ISO cameras, it is usually possible to keep your longest shutter speed high enough, if you are careful in your choice of aperture and ISO.

I would add that with Lightroom and other modern editors, that I find HDR less useful than I did a few years ago, since they are so capable of finding detail in the lower quarter tones…...

Richard

Good summary, Jim. Like you, I don't use HDR much these days because I can usually get the range I need in post if I get the exposure right to begin with.

I would add that HDR can be more trouble than it's worth if the subject is moving--Jim mentioned sports but the same may be true for street candids. While the software is very good at automatic frame alignment of static scenes, there's only so much it can do when there's motion. This can also be a problem with foliage on a windy day--you get the range but may lose sharpness. But again, it's not a hard and fast rule, and if your exposure is good you can always use the base shot and discard the over and under ones. In extreme cases (and if the shot warrants it) you can manually mask and combine separate frames as needed, which can add range without compromising focus or suffering compression flatness.

arodney

Actually I'd say there IS a right time for HDR, when the sensor can't record the entire dynamic range of the scene! If you have a 7 stop scene and a camera that records 8 stops, no need for HDR.

alaios

Thanks all for the nice answers. How do you know how many stop scenes do you have? What do you think for on camera hdr processing? My nex-f3 can do that to produce a jpeg directly.

arodney

alaios wrote: »

How do you know how many stop scenes do you have? What do you think for on camera hdr processing?

This piece might help (starts out covering the idea of dynamic range, then goes onto why you want to capture raw, especially if this range is important):
http://wwwimages.adobe.com/www.adobe.com/products/photoshop/family/prophotographer/pdfs/pscs3_renderprint.pdf

You can figure out the range using a spot meter set in the camera.

ziggy53

alaios wrote: »

... My nex-f3 can do that to produce a jpeg directly.

Specific to the NEX-F3 are both D-Range Optimizer (DRO) and HDR. In many cases DRO looks like it may be better to use if you don't plan on using RAW captures and post-processing. See the following review page for some examples of both:

http://www.dcresource.com/reviews/sony/nex_f3-review/page-0,1

If you "do" wish to use RAW captures and post-processing, tone-blending (tone fusion) is often more "natural" looking than HDR.

I typically use a combination of "Dynamic Photo HDR" (commercial software) plus EnBlend-EnFuse (open-source and free) plus EnfuseGui (also free) for my Windows machines.

http://www.mediachance.com/hdri/
http://enblend.sourceforge.net/
http://software.bergmark.com/enfuseGUI/Main.html

puzzledpaul

pathfinder wrote: »

... // shoot a bracketed exposure, photons and megabytes are cheep these days. If you decide later you do not need HDR< just delete the extra files, they cost you nothing but a bit of temporary storage //...

+ implications associated with shutter life / replacement cost, methinks?

pp

pathfinder

Paul, you are absolutely correct that shooting three or five frame HDR capture does use the shutter more than single frame exposures. But modern shutters are pretty durable.

My limited experience with shutter failures has been that they occur much earlier than one usually expects, long before typical expected shutter life expectancy, and mine were replaced under warranty by Canon. That is they were defective in some way to start with. I have had two shutters replaced by Canon Factory Service, but both were covered by warranty, even though one was past date. Generous of CFS in my opinion. I just don't worry about shutter life that much I guess.

So yes, you can indeed wear out a shutter, but modern shutters hold up to use pretty well, and most of my bodies have been replaced long before their shutters were near their life expectancy.

Now if you are shooting from the sidelines, every Sunday, for the NFL, in high speed motor drive all afternoon, then all bets are off, of course. But then someone else is probably buying your gear for you, or it is just a business expense.

I shoot far, far more frames in high speed frame rate (in non-HDR mode) when on Safari in Africa or out West, shooting wildlife, than I ever do shooting HDR frames of landscapes or people.