OCA Photography Blog: DPP-Part 2; Exercise 4

Tuesday, 12 February 2013

DPP-Part 2; Exercise 4

Exercise; Your camera’s dynamic range

I had to see how my camera copes with ‘dynamic range’, that is, how it deals with strong highlights and extremely dark shadows, even though you can adjust the camera aperture, it will read different level s across the frame.

The best dynamic range is when you have an image with bright sunlight, an area with deep shadows and a reflective surface, for this exercise I had to find such and image, keep my ISO low and turn off any noise reduction function which my camera may have (which is none).

Currently, it is quite difficult to find a sunny day; however, there was one cloudy one, where the sun came out occasionally, so I had to wait for the right moment.

When taking the photo, I used the overexposure function on my camera; to ensure there was no highlight clipping, here is the image that I took.

1/800 seconds at f/4.0 – ISO 100

Next, I then had to measure and take notes of the brightness of the white areas and dark areas, with my camera by zooming in to measure these areas, making notes of the aperture and shutter speed.

1/80 seconds at f/5.6 – ISO 100

1/25 seconds at f/3.2 – ISO 100

Then in Photoshop, I magnified the image to 100% in the highlighted area and checked with the pixel value sampler, to see what the value of the light part of my image was, the value in each channel is as follows;-

R; 236

G; 235

B; 233

Next I magnified the image again to 100%, but in the dark area, and adjusted the exposure so you could only just see the detail in the image and had to measured the area again, the value in each channel is as follows;-

R; 27

G; 17

B; 23

When lighting the shadow areas of the image, the noise was extremely apparent and did not look good, as stated in the course notes, the real detail and noise are competing with each other and there is a difficulty in telling which is which.

With regards to calculating my cameras dynamic range, I have been having a bit of trouble with this, I have used my lightest image and darkest image and calculated the f-stops in between, it seems no matter how many times I calculate this, I am coming up with is 3 stops, however, when I look at forums etc, it says that my camera has a dynamic range of 10 stops.

So on reflection, I did the experiment again, with a piece of white card and a completely black shadow, by doing this again, I came up with;-

Light; 1/500 @ f/22.0

Dark; 1/100 @ f/4.5

Which gives me a dynamic range of 7 stops, which seems more plausible, but still not correct, on this occasion, it will have to do!, on completing this again, I think I have at least tested it correctly.

I found this exercise both interesting and frustrating. Interesting to work out the dynamic range and understand my camera a lot more , but frustration due to the experiment not working correctly the first time, but as they say….if at first…..

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Books Used

Faking it: Manipulated Photography Before Photoshop
Portrait of a Young Girl by Mark Niemann-Ross
Photo truth or Photo fiction?: Ethics and Media Imagery in the Digital Age by Thomas H. Wheeler
The Art of Black and White Photography: Techniques for Creating for Creating Superb Images in a Digital Workflow by Torsten Andreas Hoffmann
Black + White Photography: all about modern monochrome by Elizabeth (ed) Roberts
Edward Weston (Photo Book Series) Terence Pitts
Ansel Adams at 100 by John Szarkowski
Understanding Exposure by Bryan Peterson
The Photographer’s Eye; Composition and Design for better Digital Photos by Michael Freeman
Mastering Digital Photography by Michael Freeman
The Digital Photography Workflow Handbook by; Juergen Gulbins and Uwe Steinmuller
The Elements Of Photography: Angela Faris Belt
Mastering Canon EOS Flash Photography: NK Guy
Light, Science & Magic: Fil Hunter, Steve Biver, Paul Fungua
The Photograph As Contemporary Art: Charlotte Cotton

Copyright

All images are owned by me, Miriam Perritt, any person/s who use my work without my authorization will face legal action.

Copyright Law
Issued: April 2000Last amended: 27th November 2009The UK copyright law fact sheet outlines the Copyright, Designs and Patents Act 1988, the principal legislation covering intellectual property rights in the United Kingdom and the work to which it applies.Introduction Copyright law originated in the United Kingdom from a concept of common law; the Statute of Anne 1709. It became statutory with the passing of the Copyright Act 1911. The current act is the Copyright, Designs and Patents Act 1988.Rights coveredThe law gives the creators of literary, dramatic, musical, artistic works, sound recordings, broadcasts, films and typographical arrangement of published editions, rights to control the ways in which their material may be used.The rights cover; broadcast and public performance, copying, adapting, issuing, renting and lending copies to the public.In many cases, the creator will also have the right to be identified as the author and to object to distortions of his work.International conventions give protection in most countries, subject to national laws.Types of work protectedLiterary song lyrics, manuscripts, manuals, computer programs, commercial documents, leaflets, newsletters & articles etc.Dramatic plays, dance, etc.Musical recordings and score.Artistic photography, painting, sculptures, architecture, technical drawings/diagrams, maps, logos.Typographical arrangement of published editionsmagazines, periodicals, etc.Sound recordingmay be recordings of other copyright works, e.g. musical and literary.Film video footage, films, broadcasts and cable programmes.The Copyright (Computer Programs) Regulations 1992 extended the rules covering literary works to include computer programs.When rights occurCopyright is an automatic right and arises whenever an individual or company creates a work. To qualify, a work should be regarded as original, and exhibit a degree of labour, skill or judgement.Interpretation is related to the independent creation rather than the idea behind the creation. For example, your idea for a book would not itself be protected, but the actual content of a book you write would be. In other words, someone else is still entitled to write their own book around the same idea, provided they do not directly copy or adapt yours to do so.Names, titles, short phrases and colours are not generally considered unique or substantial enough to be covered, but a creation, such as a logo, that combines these elements may be.In short, work that expresses an idea may be protected, but not the idea behind it.Who owns a piece of workNormally the individual or collective who authored the work will exclusively own the work and is referred to as the ‘first owner of copyright’ under the 1988 Copyright, Designs and Patents Act. However, if a work is produced as part of employment then the first owner will normally be the company that is the employer of the individual who created the work.Freelance or commissioned work will usually belong to the author of the work, unless there is an agreement to the contrary, (i.e. in a contract for service).Just like any other asset, copyright may be transferred or sold by the copyright owner to another party.Rights cannot be claimed for any part of a work which is a copy taken from a previous work. For example, in a piece of music featuring samples from a previous work, the copyright of the samples would still remain with the original author.Only the owner, or his exclusive licensee can bring proceedings in the courts.Duration of copyrightThe 1988 Copyright, Designs and Patents Act states the duration of copyright as;For literary, dramatic, musical or artistic works70 years from the end of the calendar year in which the last remaining author of the work dies.If the author is unknown, copyright will last for 70 years from end of the calendar year in which the work was created, although if it is made available to the public during that time, (by publication, authorised performance, broadcast, exhibition, etc.), then the duration will be 70 years from the end of the year that the work was first made available.Sound Recordings and broadcasts50 years from the end of the calendar year in which the work was created, or,if the work is released within that time: 50 years from the end of the calendar year in which the work was first released.Films 70 years from the end of the calendar year in which the last principal director, author or composer dies.If the work is of unknown authorship: 70 years from end of the calendar year of creation, or if made available to the public in that time, 70 years from the end of the year the film was first made available.Typographical arrangement of published editions25 years from the end of the calendar year in which the work was first published.Broadcasts and cable programmes50 years from the end of the calendar year in which the broadcast was made.Crown CopyrightCrown copyright will exist in works made by an officer of the Crown, this includes items such as legislation and documents and reports produced by government bodies.Crown Copyright will last for a period of 125 years from the end of the calendar year in which the work was made.If the work was commercially published within 75 years of the end of the calendar year in which it was made, Crown copyright will last for 50 years from the end of the calendar year in which it was published.Parliamentary CopyrightParliamentary Copyright will apply to work that is made by or under the direction or control of the House of Commons or the House of Lords and will last until 50 years from the end of the calendar year in which the work was made.Restricted actsIt is an offence to perform any of the following acts without the consent of the owner:Copy the work.Rent, lend or issue copies of the work to the public.Perform, broadcast or show the work in public.Adapt the work.The author of a work, or a director of a film may also have certain moral rights:The right to be identified as the author.Right to object to derogatory treatment.Acts that are allowedFair dealing is a term used to describe acts which are permitted to a certain degree without infringing the work, these acts are:Private and research study purposes.Performance, copies or lending for educational purposes.Criticism and news reporting.Incidental inclusion.Copies and lending by librarians.Acts for the purposes of royal commissions, statutory enquiries, judicial proceedings and parliamentary purposes.Recording of broadcasts for the purposes of listening to or viewing at a more convenient time, this is known as time shifting.Producing a back up copy for personal use of a computer program.Playing sound recording for a non profit making organisation, club or society.(Profit making organisations and individuals should obtain a license from PRS for Music.)Useful addressesIntellectual Property OfficeConcept HouseCardiff RoadNewportSouth WalesNP10 8QQTel: 0300 300 2000 begin_of_the_skype_highlighting 0300 300 2000 FREE end_of_the_skype_highlightingwww.ipo.gov.ukPRS for Music29-33 Berners StreetLondonW1P 4AATel. (0207) 580 5544 begin_of_the_skype_highlighting (0207) 580 5544 FREE end_of_the_skype_highlightingwww.prsformusic.comCopyright Licensing AgencySaffron House6-10 Kirby StreetLondonEC1N 8TSTel. 020 7400 3100 begin_of_the_skype_highlighting 020 7400 3100 FREE end_of_the_skype_highlightingwww.cla.co.ukFurther readingThe original text for the 1988 Copyright Designs and Patent Act can be found at the OSPI (HMSO) website, but should be read in conjunction with all the relevant updates and statutory instruments.To avoid confusion, we recommend a copy that includes the amendments since 1988, such as can can be found at the Office of Public Sector Information, http://www.jenkins.eu/statutes/copyright.asp or download as a PDF file directly from the Intellectual Property Office.This fact sheet is Copyright © The UK Copyright Service and protected under UK and international law. The use of this fact sheet is covered by the conditions of a Creative Commons Attribution-Non-Commercial-No Derivative Works License.This fact sheet is intended only as an introduction to ideas and concepts only. It should not be treated as a definitive guide, nor should it be considered to cover every area of concern, or be regarded as legal advice.

Tuesday, 12 February 2013

DPP-Part 2; Exercise 4

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