A Small Experiment

[RayintheUK]

I've been interested in HDR (High Dynamic Range) photography for a while, so I went to the south coast (Eastbourne) and took this (click to enlarge):



The downside to HDR is that any movement in the scene leads to a few "ghostly" artifacts, so on a public beach you've got to accept a few wispy seagulls and some faded people, I guess.

If you like it, a larger version (better quality) is here - help yourself.

Ray.

[cabinetman]

That's quite a picture Ray. Postcard quality or better (what do I know?). That shot is so clear. Did you use a tripod or a stabilizer?

I've only been using a digital camera for a couple of years, and it's a LOML hand-me-down. So, my experience with cameras has been with 35mm SLR's.

The trick with those was getting the speed and aperature right to create the depth of field. It was more about what was fuzzy, and what wasn't. Anyway, I got lucky more times than not, but never really nailed it down. Now with the digital, it works pretty good on AUTO, and I haven't experimented that much with it. I just found a little button for doing close-ups, called "macro".

Maybe when I get a windfall, I'll go for a digital SLR and feel more at home. I still have a variety of lenses for Canon, and Minolta, so maybe there will be a marriage possibility.
.

[RayintheUK]

That shot is so clear. Did you use a tripod or a stabilizer?

A sturdy tripod is essential, Mike, as the technique entails taking a number of (ideally RAW 32bit) images of exactly the same scene, but at differing shutter speeds - you just can't do that hand-held with sufficient accuracy.

You must alter only the shutter speed, because if you alter the aperture, you change the depth of field (the amount, front to back, that's sharp in the picture), which is a no-no.

Each picture needs to be of the same color temperature and tint, then they're combined into an HDR image. You can get software to help, such as Photomatix (however, this can give some "halo" effects, I've heard), but I use PhotoShop CS3 and the facility is built in - "File," "Automate," "Merge to HDR."

To produce a .jpg image means down-sampling to 8bit, so you can imagine the quality of the original is quite good! There are some really good examples here and a tutorial, showing the basics of how to do it, even with .jpg images, is here.

Ray.

[lrogers]

Very nice Ray. Those are some cool looking building. any idea how old they are?

[Popeye]

FYI Ray, I'm starting a folder just for your pictures. Pat

[bfrikken]

Real Nice! Ray - What is your camera?

Great timing on this topic, as I was jsut asked about HDR by my neighbor yesterday as he is messing around with it. He has a canon 40D that he is shooting with.

[RayintheUK]

Very nice Ray. Those are some cool looking building. any idea how old they are?

The pier was 1872, I think. Most of the current seafront buildings are circa 1880.

FYI Ray, I'm starting a folder just for your pictures. Pat

Make sure there's plenty of space in it, Pat, loads more to come!

Real Nice! Ray - What is your camera?

Great timing on this topic, as I was jsut asked about HDR by my neighbor yesterday as he is messing around with it. He has a canon 40D that he is shooting with.

I use a Pentax K10D, but any good digital camera that can shoot RAW (32bit) images will give good results. You can achieve similar results using only .jpg images, but you reduce the ceiling for adjustment from 32bit down to 8bit, so little tweaking possibilities. The 40D will shoot RAW images, so even though they take up a fair bit of room on the card, it's the way to go. HTH

Ray.

[cgallery]

Fascinating. Any chance you could post the best single shot (I guess the shot that had the most appropriate single-frame exposure time) that was used to make the HDR, so I might see the differences?

[RayintheUK]

OK, Rudy, just for you, here's a reasonably well-exposed one (click to enlarge):



The larger version is here. HTH

Ray.

[cgallery]

Thanks Ray. So the purpose of this technique is to guarantee that you don't blow out the whites and you preserve detail in the shadows?

If you take the HDR photo into PS and play with the curves, you can really reveal a lot of detail in the shadows. More so that I'd get if I tried to produce that level of shadow with a single exposure, I think.

Fascinating.

[RayintheUK]

So the purpose of this technique is to guarantee that you don't blow out the whites and you preserve detail in the shadows?

I'd say that, like any other photographic technique, there's just your imagination that puts limits on its use. Shooting in 32bit RAW gives such a wide range of out-of-camera possibilities that I doubt I'll ever do more than scratch the surface in my remaining lifetime. If you can do meaningful tweaks to a down-sampled (8bit) .jpg, I'm sure you get a hint of the possibilities. Overall, it's intended to replicate more naturally the tonal range that we can perceive, above that which center-weighted or averaged camera metering usually provides.

Ray.

[poolhound]

Nice shot Ray,

I may have missed it in the thread but how many brackets did you shoot to do this HDR?

Also Re: the seagul issue I thought HDR leaves all the layers for your to putz with afterwards so you can still do some duducious editing and fix any stray elements.

[RayintheUK]

... how many brackets did you shoot to do this HDR?

I shot five, used three.

Also Re: the seagul issue I thought HDR leaves all the layers for your to putz with afterwards so you can still do some duducious editing and fix any stray elements.

That's true, but I was so keen to merge them I wasn't really looking until I'd sampled down to the .jpg. That won't happen to the subsequent attempts.

Ray.

[Tom Slick]

That is neat! I've been reading about HDR but haven't tried it yet.
seagulls and people would be easy to "erase" in photoshop.

[poolhound]

I shot five, used three.


That's true, but I was so keen to merge them I wasn't really looking until I'd sampled down to the .jpg. That won't happen to the subsequent attempts.

Ray.

Dont you keep the orginal layered PSD file? I know they take up space but that way you can always go back and make adjustments.

A project I am working on as we speak has one thats now aproaching a file size of 150MBs and takes up way more than that when working in PS. Lucky I have lots of RAM