Pinhole photography light metering - Sekonic Blog

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Modest article on measuring light with a metre.
Sekonic blog

I think he can't spell "meter

No, he knows how to spell.

Yes, the wrong meter is annoying, especially for us metric folk... Otherwise, the article is interesting!

Marc!

pdeeh said:

I think he can't spell "meter

Click to expand...

Hi pdeeh,
you're wrong: Bob's Sekonic is a French model, see: http://www.sekonic.com/downloads/C-500_Operating_Manual_French.pdf
Also called: "un instrument demesure de la lumière".
And a beautiful language it is, French! I'm still sorry I didn't learn it properly in High School.
If you don't know what French sounds like, watch the movie "Intouchables" (French version with English subtitles). You'll laugh your "chaussettes" off.


Hi Bob,
I like your conclusion in the article: "Even with metering, pinhole photography is not an exact process, which makes it somewhat artistically unique, challenging but enjoyable. I believe there is something significant to be said for the immediate unknown … for patience … for critical thinking … for anticipation when waiting for paper or film to be processed."
I totally agree. Using digital aids isn't forbidden (not even for artists) but in the end, it still is only an end to a mean (or whatever the phrase is...). Pinhole is a way of live, not an technique.

My only problem with (most of) the light meters is being unable to set for ISO 1 and f/512, thus having to make do with tables, calculating, etc.
I now use a simple app (see also: (there was a url link here which no longer exists)) or even better: guestimation. If you use your pinhole camera often enough, you'll get the hang of it.
It worked well (there was a url link here which no longer exists).

But it is always nice to be able to measure with a proper light meter, especially when I use a camera like my Leica III (1936) or my Bronica SQ-B.
Every photographer should have a handheld light meter, just for the sake of it....
I myself use Gossen light meters. The Gossen Digisix is very small and can even be attached onto your camera.

It's amazing what people will overlook.

Here is his first paragraph, quoted directly :

Bob St. Cyr said:

Even before I added pinhole imaging to my fine-art photographic practice, I saw the value in having a handheld light metre. My first light metre was the Sekonic L-408, which is a great metre with a fixed 5° spot as well as the incident dome. Some of the things I like about this metre ...

Click to expand...

That is not how you spell "meter" when referring to a measuring device.

A "metre" as the rest of us Europeans know, is a measure of length

In his next paragraph he reverts to conventional spelling of "meter", however, but then goes on to use "meter" and "metre" indifferently throughout the rest of the article.

Meter

Why is there such a fuss over one single word.

Unfortunately, you are missing the point about the article.
It was about one man's experience measuring light for making pinhole exposures.

Sorry for spelling one word wrong ... does it affect the content of the article?

Maybe Bob should just keep all his experiences, skills and knowledge to himself ... silence is golden I guess.

Hi all,

I do it (maybe) in a little more practical way:

- My pinhole camera (Zero 45) has many different focal lengths and pinhole diameter combinations, and
- My meter measures up to F32. (Sekonic L-208)
Therefore,
- I meter for F32 then multiply this with a factor determined before (more on this below), and then
- If the resulting exposure time exceeds 1 sec. I further adjust it for reciprocity failure using this (Ilford) formula: New time = Calculated time ^ 1.48 or in Excel notation: New time = POWER(Calculated time, 1.48)

It's hard to remember and calculate each factor, therefore I prepared a simple Excel chart, printed it, and had it laminated with PVC. I keep this chart (and a scientific calculator) with the camera all the time...

See the chart (and the two formulas that I've used) below:

Formula #1:


Formula #2:


Hope this helps if you ever need to make your own practical exposure calculation charts,
Loris.

P.S. Beware, the reciprocity failure correction formula applies only to Ilford B&W films!

I can't see how one little word could be so annoying ... I just don't get it.
Is there no substance to the article.
Is this forum part of the issue I wonder.

I think it come down to the fact the basically people are rude. It doesn't matter what work somebody put into some thing people will find the smallest issue and harp on it.

Hi Bob,

I'm sorry to see that your link disappeared from your original post, but tracked the article down via your blog site anyway. I found your article really interesting, concise and easily understood - not just the how, but the why of using a light meter for pinhole work. Thanks for taking the time to write up the article and also for sharing it with those of us who enjoy learning new things and hearing about how others work.

Thank You SM Booth ... that is a very sad commentary on human nature
On the other hand, I have mitigated the word spelling, so it should be okay now.

Ignoring the pedantry --- in attempting to view this article, the intro (and apparently link) to it on your site is obscured by a redbubble slide show that I can't seem to get around?

(Running Firefox 21.0 on Win7 64bit for the 2 cents that may be worth.)

Although pinhole is not my primary interest, I have participated in WPPD every year since 2005 and keep using it as an excuse to indulge in some crazy craftsmanship on cameras!

Similar to what Loris describes, I normally make myself a pocket sized chart that goes from an exposure time for f/22 to what's needed for the specific film and camera; using reciprocity compensation if needed. The program Pinhole Designer can actually produce an Excel spreadsheet table** using readings at f/22 and has compensation for a few films built in. I usually reformat and truncate the chart, as a compensated exposure of 1795 hours seems unlikely, since I don't normally add a folding cot to my gear!

** The latest updates of Office 2007 grumble about possible security risks when opening said table, no doubt because the program dates back to the start of the millennium.