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HDR test

PostPosted: Sat May 21, 2005 11:40 pm
by sirhc55
The new PSCS2 has the ability to produce a HDR (high dynamic range) 32 bit pic from a series of photos taken with varying EV values.

The first pic was taken in manual mode with +2EV compensation and the second with -2EV compensation.

I then combined the following to produce the last image: +2EV, +1EV, 0EV, -1EV and -2EV.

I apologise for the image itself, but it was an experiment. This shows great capabilities of CS2 and I will experiment more tomorrow night on the Sydney night shoot.


Image
Image
Image

PostPosted: Sat May 21, 2005 11:56 pm
by phillipb
Hi Chris,
The third picture looks very good, but I would be interested to see it compared to a straight 0EV photo.

PostPosted: Sat May 21, 2005 11:59 pm
by mic
Chris I'm sure this is great in your Techno Minded Mind, but next time get the Girlie
dis robe ing heee hhee

I'm sure Birddog will agree. :roll:

Good test.

Mic. :wink:

PostPosted: Sun May 22, 2005 12:11 am
by sirhc55
phillipb wrote:Hi Chris,
The third picture looks very good, but I would be interested to see it compared to a straight 0EV photo.


0EV :wink:

Image

PostPosted: Sun May 22, 2005 12:19 am
by phillipb
Thanks Chris, there's definetly a lot of benefit from using HDR. I'll look forward to seeing more of this from you.

PostPosted: Sun May 22, 2005 7:50 am
by mudder
G'day Chris,
Good experiment, thanks for posting... I'm particularly interested in this aspect of PSCS2, otherwise PSCS is fine for me.

How does it compare to just merging multiple exposures using masking?

PostPosted: Sun May 22, 2005 1:09 pm
by sirhc55
mudder wrote:G'day Chris,
Good experiment, thanks for posting... I'm particularly interested in this aspect of PSCS2, otherwise PSCS is fine for me.

How does it compare to just merging multiple exposures using masking?


Masking would be much more labour intensive and it would not (to my knowledge) be working in 32 bit.

This is how it is explained in the help menu -

The dynamic range (ratio between dark and bright regions) in the visible world far exceeds the range of human vision and of images that are printed or displayed on a monitor. But whereas human eyes can adapt to very different brightness levels, most cameras and computer monitors can capture and reproduce only a fixed dynamic range. Photographers, motion picture artists, and others working with digital images must be selective about what’s important in a scene because they are working with a limited dynamic range.

High Dynamic Range (HDR) images open up a world of possibilities because they can represent the entire dynamic range of the visible world. Because all the luminance values in a real-world scene are represented proportionately and stored in an HDR image, adjusting the exposure of an HDR image is like adjusting the exposure when photographing a scene in the real world. This capability lets you create blurs and other real-world lighting effects that look realistic. Currently, HDR images are used mostly in motion pictures, special effects, 3D work, and some high-end photography

PostPosted: Sun May 22, 2005 1:14 pm
by Alex
Chris,

Thanks for this very interesting experiment. I might get CS2 version when I get a faster computer :-)

I agree with Mic. Where is a woman??

Cheers
Alex

PostPosted: Sun May 22, 2005 6:12 pm
by mudder
G'day Chris,

Thanks for the info, very interesting...

Not sure how the performance/speed would be compared to PSCS, I'm running a 2.7G P4 with 1G of RAM, I assume I'd have to upgrade to run it with any speed?

PostPosted: Sun May 22, 2005 6:31 pm
by leek
mudder wrote:G'day Chris,

Thanks for the info, very interesting...

Not sure how the performance/speed would be compared to PSCS, I'm running a 2.7G P4 with 1G of RAM, I assume I'd have to upgrade to run it with any speed?


I'm running a 2.53 GHz P4 with 1Gb and its running perfectly well... As other people have said, in some respects CS2 seems faster than CS.

PostPosted: Sun May 22, 2005 6:34 pm
by mudder
leek wrote:
mudder wrote:G'day Chris,

Thanks for the info, very interesting...

Not sure how the performance/speed would be compared to PSCS, I'm running a 2.7G P4 with 1G of RAM, I assume I'd have to upgrade to run it with any speed?


I'm running a 2.53 GHz P4 with 1Gb and its running perfectly well... As other people have said, in some respects CS2 seems faster than CS.


Thanks for the info John, looks like I might try it after all...

Cheers.

PostPosted: Sun May 22, 2005 10:07 pm
by sirhc55
Screams along on a 1.25Ghz Mac running 1Gb RAM

PostPosted: Sun May 22, 2005 10:18 pm
by -=Monty=-
It's nice having an overclocked, watercooled, 3.9ghz computer :D

But yeah, there is deffiently a big difference of the photos.
Looks good.

PostPosted: Sun May 29, 2005 11:37 pm
by leek
Hey Chris,

Here's an article on the new HDR feature that seems to support your view that it is revolutionary:
http://www.earthboundlight.com/phototip ... 32bit.html

PostPosted: Mon May 30, 2005 12:16 am
by sirhc55
Spot on Leek - given this new method one should be able to get a tonally correct image from a selection ranging from underexposed to overexposed - exciting :D