Sunday, February 20, 2011

HDR: 1st attempt

It was Friday as I was on my way to work in the early darkness. I take the northern route to work and noticed the snow clad mountains of the north shore. The sun was just starting to come alive and with the ambient light, and lights of the city blending together to form the most perfect scene for which I only had my P&S, not high enough quality for a large print. Overnight there was a slight dusting of snow which came halfway down the mountain. The light was perfect. I decided that on Saturday I would bring my dSLR and try and capture the scene. All day while at work I am trying to determine the best spot to take my photo.

My alarm goes off as usual around 5:30am and I get my camera gear ready. It is still an hour and a half before sunrise, dark and below freezing at around -2c . With frost on the windshields I decide to leave my bike at home and head down to false creek. I thought that I would get a city scene with a mountain backdrop. The light was a disappointment with the heavy cloud cover and the snow had melted from the spring-like temperatures of the previous afternoon. With my plans thwarted I thought I would just walk over the Cambie Street bridge and head downtown . I look over at Science World and capture a hint of sun coming over the horizon .

IMG_3735
(aperature priority, 0 ExP compensation)

This weekend I wanted to experiment with HDR photos. I am not sure whether any of you have tried to do HDR: High Dynamic Range photos. The human eye has a dynamic range of approx 15. A digital camera sensor can capture anywhere from 4-6 . From bright sun to dark shadows, your scene may have a dynamic range greater than what can be resolved from your camera's digital sensor. If you expose for the bright sun then you may not have enough detail in the shadows, from a single exposure.

IMG_3736
(aperature priority, -1 ExP compensation)

By bracketing your exposures you can take a series of photos above and below "normal" to get properly exposed pixels in differing light

IMG_3737
(aperature priority, +1 Exp compensation)

In this third photo it is overexposed to blow out the highs but get more detail in the shadow area.

For HDR it is recommended that you take a minimum of 3 exposures. Unfortunately for me, the Canon can only be set to take 3 shots in AEB mode. I did this series handheld in Continuous shooting mode, which means when set to AEB I click the shutter once, and it will fire 3 times, set to the range selected. I believe that my D80 can be set to take 3, 5, 7 or 9 shots in a sequence. My Manfrotto tripod is fairly heavy and since I was walking I decided to leave it behind. If I had my tripod with me I could have skewed the AEB in both directions and get 6 (or more) shots, but as I was shooting hand held there was no way I could get exactly the same perspective as I have to move the camera from my eyes to skew the AEB range.

Now here is the final result of blending these 3 exposures together to achieve a higher dynamic range that the sensor could natively capture. Of course, since this is my first attempt at HDR I tweaked the curves a bit, bumped up the contrast, played with the tint, and also altered the light balance and increased the saturation to about 120% . It is the first time I have used this software so I wanted to see its capabilities

IMG_3737-HDR
(HDR: overtweaked and oversaturated)

There were so many sliders and options so I just had to try them all to see what would happen.

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Later in the day after brunch I headed down to the harbour in the industrial area. I was walking over an overpass with train tracks below and noticed a scene brightly lit with deep shadows from the low sun angle of winter . It was just perfect for another HDR

IMG_3781
(perfectly exposed as viewed from histogram, Zero ExP compensation)

This is how most cameras would expose for this scene. Notice it is hard to see details in the shadows.

IMG_3782
(minus -1 ExP compensation)

Underexposure keeps the bright area from clipping and provides more accurate colour for the red buildings

IMG_3783
(plus +1 ExP compensation)

Overexposing blows out all the bright areas of this scene, but provides more details in the dark areas along the railway tracks.

The HDR merged image is below. Only slightly tweaked with; curves, slight oversaturation which made the red buildings "more" red, and a slight colour temperature change to a warmer tone, approximating late summer.

IMG_3783-HDR
(Final HDR image, Vancouver Harbour)

16 comments:

  1. Wow, the 3-layered False creek picture looks surreal, almost otherworldly and futuristic. Great work.

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  2. Wow, I have got to try this! What software did you use to blend them together? My Nikon D200 has exposure compensation, but you have to hit the shutter 3 times to get the 3 different exposures, or 5 times to get 5 etc. I have previousoly thought I might give it a try, but was put off by having to carry a tripod to get identical composition, but I do understand that some HDR software can also stitch slightly different (handheld) shots together seamlessly. When the sun eventually makes an appearance in the UK, I will go and give it a try.

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  3. I meant to say.... the harbour shot is, as you said, a little too over-tweaked, but unless you try those things you don’t learn the capabilities I guess. The way that you can now see into the shadows in the railway shot is impressive.

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  4. Stunning photos Bob! I see on one of our news sites that Vancouver has been voted as the world's best city to live in. I can see why!

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  5. Interesting results. I think that the Vancouver Harbour shot with the train tracks in the shadows looks pretty good. It really demonstrates the benefit of hdr. Colors seem "normal". Actually, the one of the science center looks pretty cool too. Like Sonja said, it looks kind of other worldly...

    I've been playing around with this just on the iPhone and have generally been dissatisfied with the results. They always look a little overexposed....

    Richard

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  6. SonjaM: The trick is not to overdue the post processing but I wanted to try out all the options. The second photo is more realistic

    Gary: You don't have your drive mode set to "Continuous" then One click will take all the shots. The software also autoaligns so you can shoot handheld. I sent you an email

    Jim: take it easy, glad you are still with us. Rest and snap your fingers for service. I tried to lift up my old CRT TV and strained my back. It's hard to think that we can't do things that we used to do in our youth

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  7. Geoff: Vancouver seems to come near the top of most recent surveys but it's becoming expensive to live here. We have the highest housing prices in North America, so monetarily it's getting more difficult

    RichardM: the harbour shot is precisely what HDR is for. It's for when you have a great contrast range in one scene. Handheld I can only do 3 shots AEB. But with a tripod I will shoot 6 shots at 2/3'rds F stop increments.

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  8. I do like the tweeks for the Science World shot. With the wonderful golds and blues it doesn't look realistic...but that is what I like about it, that surreal look and the sparkles!!

    Which software are you using?

    -Lori

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  9. Oh man, I should have waited to read this. It's late and I have a dozen questions! I've attempted a couple of HDR with disappointing results. (only have photoshop). I need to look into some other software, but haven't had time. I do quite a bit of hand blending with layers.

    I'm seeing more HDR images pop up in my camera club. People seem to have a love/hate relationship with the overcooked HDRs. I like the effect, but I tend to categorize it as photo art, rather than photography. For regular photography I like a more subtle HDR, where it's used as an enhancement to dynamic range. That's just me.

    I like the effect in the cityscape. It's more like photo art to me, but it looks really cool. I think over-tweaked HDR can be a fun effect with this type of scene.

    The last image looks more natural/subtle. This is what I prefer for straight photography, and seems to work best for natural scenes like landscapes.

    Which HDR program are you using, if you don't mind me asking?

    Awesome post Bob!
    Now I have to go get some sleep!
    ps -sorry for the long comment! :)
    Good night!

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  10. I liked the tweaking...some HDR's try to look natural, but actually look fake...the tweaking on the first one made it an interesting artistic statement...

    What HDR program are you using???

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  11. This is pretty cool, I'm really happy to have the info. I picked up a T1i recently since I was doing more traveling and writing, but it's difficult to master the complexities of a camera as such. I often run into the exact problem you're talking about. I had no idea this was even possible - without a group of camera-fiend friends it's tough to learn this.

    I appreciate this for being informative but not fanatic. And, like everyone else, I want to know what software are you using?

    Brady
    Behind Bars - Motorcycles and Life
    http://www.behindbarsmotorcycle.com/

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  12. BeemerGirl: The first one was oversaturated on purpose. The second was done more realistically. glad you liked them

    BlueKat: Great minds think alike, what a co-incidence you were attempting HDR at the same time

    ps: you don't need anymore beauty sleep

    Kathryn: thank you for stopping by, I left you a blog comment

    Brady: HDR is like compressing the dynamic range into an image which can be displayed on your standard monitor. Not unlike the Zone system of film days where you would "Pull" develop film. I found a great FREE program

    oloneo.com watch the demo video on the home page. It is also a great RAW converter which supports most cameras.

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  13. Cool, thanks. I'll definitely check that out.

    Brady
    Behind Bars - Motorcycles and Life
    http://www.behindbarsmotorcycle.com/

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  14. Oh, curse you! I've never heard of the whole HDR thing. Now I have something else to add to my list of things I gotta try! :-)

    I love the overtweaked & oversaturated science center shot.

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  15. Hi bobskoot,

    Thanks for visiting me on flickr. Re: you HDR question/suggestion there. Yes, I've tried it and it's a nice skill to know but I'd much rather get things right in camera and spend a minimal amount of time at the computer tweaking. I prefer realistic as possible images. As you know, lots of flickr folks are rabid HDRers. I do like some of the single file HDR (yes, you can apply HDR to one file) who tend to be less heavy handed; but, too much of HDR has, for me, become cartoonish.

    I do like your experimenting here. Just remember that little goes a long way. You might want to try single file HDR to see if you like that. Check out the many many HDR communities on flickr and you'll know what I mean. BTW, I really like your new header (new to me at least). Thanks again. It's always nice "seeing" you on flickr.

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