Open Photography Forums  
HOME FORUMS NEWS FAQ SEARCH

Go Back   Open Photography Forums > Photography Discussions > Studio, Portrait, Still Life, Lighting Equipment and Technique

Studio, Portrait, Still Life, Lighting Equipment and Technique Continuous and Strobe Lighting. (The Sun is considered continuous!) Great ideas are really ten a penny! Technique in setting up the subject is, of course, essential. However, the ability to bring out form, texture, tonality and color is where the skill in lighting provides all the keys to engraving one's ideas on the delivered picture.

Reply
 
Thread Tools Display Modes
  #1  
Old November 3rd, 2018, 08:09 PM
Doug Kerr Doug Kerr is offline
Senior Member
 
Join Date: May 2006
Location: Alamogordo, New Mexico, USA
Posts: 8,566
Default Still life with slide rules and reactance paper

From 2009:



Douglas A. Kerr: Still life with slide rules and reactance paper

The upper slide rule is my father's; it was this that he used to first teach me how to use a slide rule. It has little index marks scribed on it that were constants he used in his work for calculating the weight of steel that would be in large cylindrical parts and so forth.

The lower slide rule is the one I used in engineering school. My father actually bought it for me.

On the right is a sheet of reactance paper, a special graph paper that facilitates graphical determination of the resonant frequency of an L-C circuit and such. It is Bell Telephone Laboratories issue.

Best regards,

Doug
Reply With Quote
  #2  
Old November 3rd, 2018, 08:26 PM
Peter Dexter Peter Dexter is offline
Senior Member
 
Join Date: Nov 2016
Location: Colombia
Posts: 749
Default

Doug what a nice still life. My father, an electronics engineer also taught me how to use a slide rule. But now I've forgot!
__________________
Please do not edit my photos
Reply With Quote
  #3  
Old November 3rd, 2018, 08:44 PM
Asher Kelman Asher Kelman is offline
OPF Owner/Editor-in-Chief
 
Join Date: Apr 2006
Posts: 34,785
Default

In my days at school a slide rule was essential and there was the debate as to whether it was fair to exclude it from physics exams. Some thought it made us lazy, LOL. The paper I have never seen before. Log-Log paper was advanced as I got!

Asher
__________________
Follow us on Twitter at @opfweb

Our purpose is getting to an impressive photograph. So we encourage browsing and then feedback. Consider a link to your galleries annotated, C&C welcomed. Images posted within OPF are assumed to be for Comment & Critique, unless otherwise designated.
Reply With Quote
  #4  
Old November 4th, 2018, 10:53 AM
Doug Kerr Doug Kerr is offline
Senior Member
 
Join Date: May 2006
Location: Alamogordo, New Mexico, USA
Posts: 8,566
Default

Hi, Asher,

Quote:
Originally Posted by Asher Kelman View Post
In my days at school a slide rule was essential and there was the debate as to whether it was fair to exclude it from physics exams.
Yes, teh same was a concern when I was in engineering school.

When I was involved with a technical college (1973-1978), there was a debate as to whether hand calculators (typically the "four banger" type) should be allowed in class (for use in exercises, etc.) A related controversy was whether we should sell these in our bookstore, or whether a student with a scholarship should be allowed to spend any of it on a calculator.

Quote:
The paper I have never seen before. Log-Log paper was advanced as I got!
Yes, it is specialized to electrical engineering, and many never encountered it.

It has a basic log-log scale setup, the two axes being frequency and reactance.

Superimposed on that were diagonal lines (on a logarithmic spacing) that correspond to values of inductance and (in the opposite direction) capacitance.

If you wanted to know what reactance a certain capacitance would have at a certain frequency, you chose the capacitance line for that capacitance and then, from where it intersects the vertical line from the horizontal scale for the desired frequency, follow the horizontal line to the vertical scale and read the reactance.

It was a very clever tool.

Best regards,

Doug
Reply With Quote
  #5  
Old November 6th, 2018, 11:47 AM
Jerome Marot Jerome Marot is online now
Senior Member
 
Join Date: Jan 2011
Location: Munich, Germany.
Posts: 3,789
Default

I have two slide rules, from my late father. I never actually used a slide rule, when I started to learn about logarithms, the HP-35 was already a thing (although I never owned one).

Now, if I am allowed to make a comment: why the fruits on what is a picture of slide rules and reactance paper?
Reply With Quote
  #6  
Old November 6th, 2018, 12:25 PM
Doug Kerr Doug Kerr is offline
Senior Member
 
Join Date: May 2006
Location: Alamogordo, New Mexico, USA
Posts: 8,566
Default

Hi, Jerome,

Quote:
Originally Posted by Jerome Marot View Post
I have two slide rules, from my late father. I never actually used a slide rule, when I started to learn about logarithms, the HP-35 was already a thing (although I never owned one).

Now, if I am allowed to make a comment: why the fruits on what is a picture of slide rules and reactance paper?
Because it is a custom of artists to have fruit as the subject of a still life.

So this is sort of a joke.

It is not captioned as a "picture of slide rules and reactance paper", but rather "with slide rules and reactance paper".

Best regards,

Doug
Reply With Quote
  #7  
Old November 6th, 2018, 03:47 PM
Jerome Marot Jerome Marot is online now
Senior Member
 
Join Date: Jan 2011
Location: Munich, Germany.
Posts: 3,789
Default

Quote:
Originally Posted by Doug Kerr View Post
Because it is a custom of artists to have fruit as the subject of a still life.
Not as much as you would think.
Reply With Quote
  #8  
Old November 6th, 2018, 05:23 PM
Jim Galli Jim Galli is offline
Senior Member
 
Join Date: Nov 2007
Posts: 701
Default

Years ago when we were doing calcs and arguing digital vss film back in formative days, one of the engineers visiting from abq asked me if I had a calculator and I handed him my 1959 Post aluminum slide rule. He was not amused.
__________________
He is no fool who gives what he cannot keep..to gain that which he cannot lose. Jim Elliot, 1949

http://tonopahpictures.0catch.com
Reply With Quote
  #9  
Old November 7th, 2018, 01:43 PM
Michael Nagel Michael Nagel is offline
Senior Member
 
Join Date: Jan 2011
Location: Munich/Germany
Posts: 2,289
Default

Never used a slide rule in school, but learnt to use it anyway.
I still have a slide rule, the disc variant of it and I still have my logarithmic tables.
It was just the transition to widespread use of the electronic calculator in school for me (TI-30 to name one).

Best regards
Michael
__________________
I do not call myself an artist, I just try to capture what I see.
If you need many words to describe what your picture means, it doesn't speak enough for itself.
my photos on flickr - here is the portion posted in OPF.
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
slide shows to dvd sandy lankford Image Processing and Workflow 5 June 25th, 2013 06:52 AM
Fun: Still life with slide rules and graph paper Doug Kerr Studio, Portrait, Still Life, Lighting Equipment and Technique 11 March 29th, 2009 05:45 AM
Slide copying - adjusting in RAW Chuck Bragg Image Processing and Workflow 12 January 2nd, 2007 11:20 AM
Pro quality DVD slide shows for mac Paul Bestwick Macintosh 5 December 3rd, 2006 05:02 PM
Slide reproduction with 100mm macro. Don Finch Lenses: DSLR and Rangefinder, MF adaptions to 35mm such Zoerk 9 September 2nd, 2006 11:32 PM


All times are GMT -7. The time now is 01:19 PM.


Posting images or text grants license to OPF, yet of such remain with its creator. Still, all assembled discussion 2006-2017 Asher Kelman (all rights reserved) Posts with new theme or unusual image might be moved/copied to a new thread!