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HDRI Photography - My new hobby

Posted: Tue Aug 05, 2008 2:35 am
by KiLlEr
Unbeknown to you all, I'm also an avid photographer (well, some of you may know) and lately I've been having fun learning about the HDRI photography technique. Below are some of my work.

These first ones are my initial attempts. They were more for playing with the multitude of HDR merging and tone mapping programs out there, in order to determine which one I liked best. I will only post the ones from Dynamic HDR otherwise it'll be too much. LOL

Image Image Image

I've tried Picturenaut, Dynamic HDR, Photomatrix, as well as others. I've since settled on Dynamic HDR and below are the more refined and practiced attempts. The last of which is the most recent, for which there is a "normal" or more natural looking HDR tone map, and the other is more extreme. Although there is a significant increase in noise with the extreme version, you will also notice far more clouds which are hidden to the naked eye. Well, in all actuality, it was so dark you couldn't see the sky anyway. LOL

Image Image Image


I decided on Dynamic HDR as it gave me the most flexibility, and really good results. :D

The HDR (High Dynamic Range) technique is quite simple. All you need to do is take multiple exposures of the same scene at different shutter speeds. The lower speeds captures shadow detail, and the higher speeds capture highlight detail. The trick is knowing how many exposures you need, and at what spacing. It takes a few attempts, but like with everything else, practice makes perfect. ;)

Then you import the photos into an HDR merging program (Photoshop CS2 and up has this as well). This creates a 96bit color image, which cannot be displayed. The next step is to Tone map the image back into 24bits. Photoshop CS2 can do this, but it sucks. Hence the need to hunt for a more capable program.

Anyway, I'll be posting more so be on the look out, ne? (^.^)

Posted: Tue Aug 05, 2008 3:48 am
by KiLlEr
Here are the 3 shots that went into the last sample. Keep in mind 2 things:

1 - the originals were 10x larger
2 - the originals were 32 bit RGGB images (i.e. Camera Raw)

so there is a lot more information in the original files than whats seen below.

This image captured the lamps and the stars (i.e. Highlights)
Image

This captured the colors, mid tones, and lighting
Image

This captured the shadow details and colors
Image

Posted: Wed Aug 06, 2008 4:02 am
by LeoXiao
The last two on the first post are the best.

Posted: Wed Aug 06, 2008 4:29 am
by KiLlEr
The best time for photos is the 30 mins after the sun goes down or the 30 mins before the sun comes up. Thats when you get that really magical light.

The first 3 were just to try out the software and were taken on a rainy day at noon when the sky was a solid grey. But it was enough to test the software. :)

Posted: Wed Aug 06, 2008 9:38 am
by HELLFIRE
:drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool: :drool:

Very nice work Killer. Maybe it is time to consider getting a DSLR and jumping further into photography...




Regards

Posted: Thu Aug 07, 2008 7:54 pm
by KiLlEr
If you decide on one, go for a Cannon. :)

http://www.dpreview.com is your friend.

I use an Olympus E520 . I started with an Olympus E500 kit with 2 lenses. The reason I got that was purely financial (The kit was a steal). Since then I added on 4 semipro lenses and a pro flash. Since I invested in them, I was reluctant to sell everything and start over and ended up with the E520. I made money on the E500 w the 2 lenses by selling it for 50 USD more than what I picked up the E520 body for. Its a great beginner kit (E500 + 2 kit lenses) which is why I was able to sell it. But the addons I have wold have put it beyond a beginners pricing, and a more pro user would rather buy a Nikon or Cannon.

But If I had the choice to start over, I would've gone for a Canon. Probably the Canon EOS 450D / Digital Rebel XSi

Just my 2 cents.

You don't need an SLR to do HDRI. all you need is a digital camera with arpeture priority mode and a solid tripod. If your camera has Auto Exposure bracketing with a 3 shot range of +2,0,-2 then you have an advantage. Otherwise you need to manually adjust the exposure, which takes longer.

The E520 has AE bracketing, but the range is +1,0,-1 which is not wide enough, so I have to do the manual thing.

Some tutorials on the web:

http://www.photoshopcafe.com/tutorials/ ... hdr-ps.htm
http://www.vanilladays.com/hdr-guide/
http://abduzeedo.com/how-create-hdr-pho ... x-tutorial
http://www.popphoto.com/howto/3038/how- ... mages.html

Posted: Fri Aug 08, 2008 2:32 pm
by HELLFIRE
// dizzy

....ohkay, time to dust up (literally) on what some of those terms mean...

I already have a Panasonic FZ7 which I'm quit happy with, stuff like this and
others just gives me the excuse to (waste) the money on something fancier :-D




Regards

More HDRI Images - Enjoy!

Posted: Sun Aug 17, 2008 9:59 pm
by KiLlEr
Image - Image - Image - Image
Image - Image - Image - Image
Image - Image - Image - Image
Image

Posted: Sat Aug 23, 2008 4:17 am
by KiLlEr
Image Image

These are alternate renderings from above.

Posted: Sun Aug 24, 2008 1:26 am
by LeoXiao
Hey those are actually pretty good. Are these photos unaltered?

Posted: Sun Aug 24, 2008 6:21 am
by KiLlEr
Unaltered? hmmm...... depends on how you look at it.

They're High Dynamic Range images. Basically, they are several exposures taken of the same scene, which are merged into an image that has floating point rgb values allowing for near infinite dynamic range. A 24 bit image has a dynamic range of 255. So, in order to be able to display the HDRI, you have to compress the dynamic range back down to 255 levels. This is called tone mapping. So, depending on how you tone map it (there are hundreds of different algorithms) it will have a different look.

The above 2 use an algorithm called "eye catching" which varies the compression based on how much the luminosity varies in a 10x10 pixel area, and an input curve (4 curves actually, one for luma, one for red,one for green and one for blue).

So these pictures are of an actual scene, and the images themselves where only edited for noise and dust specs. But the lighting is exaggerated, due to the tone mapping algorithm used.

But one can argue that the actual lighting in the scene cannot be viewed on a standard monitor, so the exaggerated lighting is an approximation of the actual scene. Hence, you can say that the images are in fact "unaltered" since the display device is incapable of rendering the real scene.

However, you can also argue that since they have to be processed to be viewed, they are therefore altered since the original photos donot look like the end result.

But I can also argue that the original photos are actually altered, since they have limited dynamic range and cannot capture the lighting as seen by the naked eye.

For example, in the batch of images above, the upper left one of my couch is a prime example of this. Sitting opposite of he couch I can clearly see the room, the couch, the window, and the view outside just as the image shows. However, there is no camera in the world that can take such a picture. If I expose for the room, the view from the window would be pure white, and the window would be washed out. If I expose for the outside view, everything else would be pitch black.

So, is the resulting Tone Mapped HDRI, which closely depicts what I see "unaltered"? Or is it considered "altered" because it is a processed image that cannot be taken normally with a camera? Depends on what you consider real, your eyes, or the limited abilities of a camera.

I choose not to dwell on such things. If it looks good. It looks good. Thats all that matters. I leave the rest to purists, politicians, theorists, and philosophers.. :)

Posted: Sun Aug 24, 2008 9:29 am
by Taurec
Bleeping hell they look cool.

I'm in the market for a dslr, and am thinking about a 450 with a tamron or sigma 18-200 lens (am a lazy dude so don't want to swap lenses often)

Posted: Sun Aug 24, 2008 8:11 pm
by KiLlEr
Tamaron and Sigma (Opteka, et al) are pretty crappy lenses. I had a few over the years and rarely do I get a good one. Even the same model has dramatic variation in quality since QA is something that they have no concept of.

I'd save my cash for better glass since you will always get better results with a semi-decent body and a great lens, than the other way around. The lens is the most important, which is why I tend to stick with Olympus. Zuiko makes the best lenses, hands down. I just wish they'd put a better sensor in the 4/3 cameras. The Cannon's have the best sensors on the market, but there is a limited selection of good glass. Although, Glass for Cannon's are cheaper than the rest, due to competition.

I'm assuming you're looking at:

http://www.popphoto.com/cameralenses/46 ... os-af.html

thats a pretty slow lens (3.5 to 6.3). You'll only be able to use the upper 2/3rds of the zoom outside on a sunny day.

http://www.dcviews.com/lenses/Sigma-lenses.htm

a good lens site

Posted: Tue Sep 16, 2008 2:05 am
by KiLlEr
Image

For some reason, the software was not bringing out the moon. But its an interesting pic. :)

Posted: Tue Sep 30, 2008 7:28 pm
by Taurec
Contrast goes wild .... :)
A little too much noise in the sky....
But this sure keeps interesting.