My Early Experiments in HDR

*From:* "Annika1980"
*Date:* 12 May 2006 03:08:04 -0700

Randy Howard wrote:

Also, while digital technology is advancing rapidly (while film
is,
well ..... dead there is some concern over whether today's file
formats could be read at all in 50 years.

Not by anyone with even a modicum of clue. The file formats are
well documented. Nevermind all of the open source code out
there that can do it.

This assumes you'll still be using the same Windows or Mac type box in
50 years.


No, but it does assume that you have a way to interface to whichever
medium holds the files.

This might be trickier - look at all the 8" floppy readers you can buy
nowadays.

At least successive media readers based on 5.25" optical media have so
far maintained backwards compatibility, a Blu-Ray or HD-DVD drive should
still be able to read the earliest kind of CD-ROM.

The cost of access to data on obsolescent media will steadily rise
though. To maintain cheap access over the years you really ought to
regularly copy everything you have onto newer media.

This raises its own problems, in regular media costs and time to do the
copying.

Compared to leaving some negatives in a folder for 100 years, it is a
problem, and one that will only grow with the volume of images on
digital media.

However, here's the flip side.

For a while I've had most of my possessions in storage. All my digital
pictures are still available to me on hard disc, but all my film ones
are in storage. Digital images can be easily copied, so they're far more
resistant to issues of losing access to or entirely losing the originals.

Dave Martindale wrote:
writes:

I wanted to make certain that is what he had in mind, because when he
states, "converting an HDR image into an 8-bit pc image renders a
rather washed out and grey result," his statement makes no sense.

It makes sense if you assume, like I do, that "8 bit" means 8 bits per
channel. That could be 8 bits total in a greyscale image, 24 bits total
for RGB, or 32 bits total for RGBA - they're all 8 bit images.

I understand you are referring to 8-bits per channel. That does not
explain how someone can claim that images that have 8-bits per channel
(total of 24 bits per pixel) are "rather washed out and grey." In
particular, where do you get grey out of neon?

Annika1980 wrote:
Mardon, you're photo is probably the best implementation of HDR that
I've yet seen.

Oh, I don't know... it seems cliche.

http://members.aol.com/pooua/Bright_...ight_Light.wmv

wrote:

[snip]

I still think you need to find a better subject for your photographs,
here's one of my favorites:

http://galleries.oomz.net/pub/clived...144856-HDR.jpg

Nice. But, I live in Texas, where the sun is often bright on cloudless
days:

http://members.aol.com/pooua/HDR/HDR...-001_small.jpg

In message .com,
wrote:

Nice. But, I live in Texas, where the sun is often bright on cloudless
days:

http://members.aol.com/pooua/HDR/HDR...-001_small.jpg

You need to clean your sensor, and learn to expose to the right.

There is no reason to under-expose an image in that kind of lighting.
--


John P Sheehy

wrote:
In message .com,
wrote:

Nice. But, I live in Texas, where the sun is often bright on cloudless
days:

http://members.aol.com/pooua/HDR/HDR...-001_small.jpg

You need to clean your sensor,

I think it was actually my lenses that had water spots on them. At
least, that is what I am hoping.

and learn to expose to the right.

As opposed to the left?

There is no reason to under-expose an image in that kind of lighting.

If that image were under-exposed, you would not be able to see the
facial features of the statue. If it were over-exposed, you would not
be able to see most of the background detail. A normal photograph
cannot capture both the detail of the statue's face and the background
details of the fountain, the traffic and the stores. But, the fact
remains, the photograph is not under-exposed.

Oh, and would it have killed you to acknowledge that I captured
distinct water drops in the air in an HDR image? You know that movement
does not normally work well in an HDR image.

wrote:
wrote:

In message .com,
wrote:


Nice. But, I live in Texas, where the sun is often bright on cloudless
days:

http://members.aol.com/pooua/HDR/HDR...-001_small.jpg

You need to clean your sensor,


I think it was actually my lenses that had water spots on them. At
least, that is what I am hoping.

It's dust on your sensor. You can get rid of 99% of it with just a blower.



and learn to expose to the right.


As opposed to the left?

Yes, right is generally the opposite of left.



There is no reason to under-expose an image in that kind of lighting.


If that image were under-exposed, you would not be able to see the
facial features of the statue. If it were over-exposed, you would not
be able to see most of the background detail. A normal photograph
cannot capture both the detail of the statue's face and the background
details of the fountain, the traffic and the stores. But, the fact
remains, the photograph is not under-exposed.

Oh, and would it have killed you to acknowledge that I captured
distinct water drops in the air in an HDR image? You know that movement
does not normally work well in an HDR image.


Wooohooo!

Greg

--
"All my time I spent in heaven
Revelries of dance and wine
Waking to the sound of laughter
Up I'd rise and kiss the sky" - The Mekons