DPChallenge: A Digital Photography Contest You are not logged in. (log in or register
 
Challenge Entries
Portfolio Images
This image is not part of a public portfolio.
Introspection
Introspection
alfresco


Photograph Information Photographer's Comments
Challenge: Spots (Basic Editing)
Camera: Nikon D70
Lens: Nikon AF-S DX NIKKOR 18-200mm f/3.5-5.6G ED VR II
Location: Viva Las Vegas
Date: Nov 9, 2006
Aperture: f/5.6
ISO: 200
Shutter: 1/50
Galleries: Emotive, Animals
Date Uploaded: Nov 14, 2006

To appease the isotope geochemist in me, from the USGS

Isotope Terminology

In everyday speech, isotopes are still described with the element name given first, as in "oxygen-18" or "O-18" instead of "18- oxygen". And many texts, especially older ones that were typeset without superscripts, show the mass number to the right of the element abbreviation, as in C-13 or C13 for carbon-13. However, both in speech and in media, it is becoming more common to put the mass number before the element name, as is 15N.

The stable isotopic compositions of low-mass (light) elements such as oxygen, hydrogen, carbon, nitrogen, and sulfur are normally reported as "delta" (d) values in parts per thousand (denoted as ‰) enrichments or depletions relative to a standard of known composition. The symbol ‰ is spelled out in several different ways: permil, per mil, per mill, or per mille. The term "per mill" is the ISO term, but is not yet widely used. d values are calculated by:

(in ‰) = (Rsample/Rstandard - 1)1000

where "R" is the ratio of the heavy to light isotope in the sample or standard. For the elements sulfur, carbon, nitrogen, and oxygen, the average terrestrial abundance ratio of the heavy to the light isotope ranges from 1:22 (sulfur) to 1:500 (oxygen); the ratio 2H:1H is 1:6410. A positive d value means that the sample contains more of the heavy isotope than the standard; a negative d value means that the sample contains less of the heavy isotope than the standard. A d15N value of +30‰ means that there are 30 parts-per-thousand or 3% more 15N in the sample relative to the standard.

In ASCII-only media, the term delta is almost always denoted with the small Greek letter d. In media lacking this symbol, it is not- uncommonly replaced informally with the letter "d". The term d is spelled and pronounced delta not del. The word del describes either of two mathematical terms: an operator or a partial derivative.

Many isotopers are very sensitive about misuses of isotope terminology. Harmon Craig's immortal limerick says it all:

There was was a young man from Cornell
Who pronounced every "delta" as "del"
But the spirit of Urey
Returned in a fury
And transferred that fellow to hell

There are several commonly used ways for making comparisons between the d values of two materials. The first three are preferred.

* higher vs. lower values
* heavier vs. lighter (the "heavier" material is the one with the higher value)
* more/less positive vs. more/less negative (eg., -10‰ is more positive than -20‰)
* enriched vs. depleted (remember to state what isotope is in short supply; eg., a material is enriched in 18O or 16O relative to some other material).

Statistics
Place: 16 out of 175
Avg (all users): 6.3867
Avg (commenters): 7.1500
Avg (participants): 6.2206
Avg (non-participants): 6.4468
Views since voting: 2023
Views during voting: 381
Votes: 256
Comments: 24
Favorites: 1 (view)


Please log in or register to add your comments!

AuthorThread
11/29/2006 08:58:52 AM
Congrats on being in the top 20 :) Nice work to capture this majestic expression.
  Photographer found comment helpful.
11/23/2006 04:30:28 PM
Beautiful photograph, congrats on your high finish!
  Photographer found comment helpful.
11/22/2006 02:05:37 AM
Congratulations on your top twenty finish with this interesting capture.
  Photographer found comment helpful.
11/22/2006 01:26:07 AM
I still don't understand how this scored so well. Look at all the lost detail in the chest area, and the overall image is horribly oversharpened. The quality of the blurred background is so bad that it makes it look like the animal is cut out and pasted on to the bg.

I'm sorry, I just don't get it.
  Photographer found comment helpful.
 Comments Made During the Challenge
11/21/2006 09:13:57 AM
nice shot, a little over sharpened but a great capture
  Photographer found comment helpful.
11/20/2006 07:30:24 PM
The skin seems to have lost some texture from some type of Noise removal software, but I reall like the expression on the face.
  Photographer found comment helpful.
11/19/2006 07:09:00 PM
Very interesting to look at.
  Photographer found comment helpful.
11/19/2006 05:00:48 PM
It looks like you have a little sharpening halo on the right side, and he seems a little cramped in the photo. Some of your whites are just a wee bit blown out, but honestly that's all just fishing for something to improve on. You're still in my top 5 picks, heh.
  Photographer found comment helpful.
11/18/2006 07:06:49 PM
0-2 meets challenge = 2
0-3 creativity = 3
0-3 technical merit = 3
0-2 biased wow factor = 2
Total 10
Nicely done!
  Photographer found comment helpful.
11/17/2006 12:05:10 PM
fits the frame, and the challange, sharp focus, good exposure, well deserved 10
  Photographer found comment helpful.
11/17/2006 09:03:50 AM
nice clean sharp focus
  Photographer found comment helpful.
11/17/2006 05:29:51 AM
terrific sharpness. perhaps a bit too high the usm but 10.
  Photographer found comment helpful.
11/16/2006 10:26:13 PM
to many halos from sharpening ..
  Photographer found comment helpful.
11/16/2006 02:19:03 PM
Nice capture, although I think the PP lets it down a bit. 6
  Photographer found comment helpful.
11/16/2006 01:54:25 PM
beautiful shot and I can,t find fault in it 10
  Photographer found comment helpful.
11/16/2006 08:30:22 AM
A little too much noise reduction.
  Photographer found comment helpful.
11/15/2006 09:15:36 PM
great shot!
  Photographer found comment helpful.
11/15/2006 03:59:01 PM
Beautiful cat. I love the colors. Only improvement I would suggest is to not crop off the paws.
  Photographer found comment helpful.
11/15/2006 01:27:19 PM
Cool photo. Looks like something got lost in post-processing as this animal almost looks unreal in some places (interior of nose next to the eye, the outside left fur on the neck, and the white on the chest). Perhaps it's natural that way? The fur on the forelegs looks natural. Hmmm. I like how you've filled the frame with the animal. Good luck in the challenge.
  Photographer found comment helpful.
11/15/2006 12:32:59 PM
Looks a bit oversharpened to me - but I like the pose...
  Photographer found comment helpful.
11/15/2006 05:10:14 AM
too much softening for my taste
  Photographer found comment helpful.
11/15/2006 01:07:18 AM
LOVE IT! Super lighting.10
  Photographer found comment helpful.
11/15/2006 12:35:54 AM
Way oversharpened and neat imaged.
  Photographer found comment helpful.
11/15/2006 12:31:05 AM
Wonderful image here, excellent example of spots.....
  Photographer found comment helpful.


Home - Challenges - Community - League - Photos - Cameras - Lenses - Learn - Help - Terms of Use - Privacy - Top ^
DPChallenge, and website content and design, Copyright © 2001-2025 Challenging Technologies, LLC.
All digital photo copyrights belong to the photographers and may not be used without permission.
Current Server Time: 03/12/2025 06:21:36 PM EDT.