[alt-photo] Re: Ultra Long Exposure Reciprocity Failure?

[Diana Bloomfield]

Hey Francesco,

Maybe I'm still not clear on what you're asking, but I know they're  
have been a lot of pinhole photographers who have set cameras out for  
weeks and months at a time.  Greg Kemp, for one, has done that--  
months long exposures-- don't know if he used film or paper, though.   
I'm sure there are plenty of others out there (mostly pinhole  
photographers that I know of) who could give you their experience.   
Somebody here might have Greg's current email address, too.  The last  
time I wrote to him, the old email I had bounced back.  (And didn't  
the Ostermans just have their show at Tilt, from Lacock Abbey, where  
they had their cameras out for a long period of time (weeks?), or am I  
mistaken??

Diana
On Jan 20, 2012, at 9:49 AM, Francesco Fragomeni wrote:

> Hi everyone,
>
> Thanks for the information and insight. I wanted to offer a quick
> clarification so that everyone is on the same page as I am when I say
> "ultra long exposures". I'm talking about exposures well beyond  
> hours. I'm
> referring to exposures in the duration of weeks, month, and even  
> years. The
> extreme nature of such exposures is what led me to believe that  
> there may
> be a possibility that reciprocity failure behaves differently or  
> becomes
> irrelevant entirely with such long exposures. I've done pinhole  
> exposures
> and lensed long exposures into the hours before without much problem
> (mainly based on the times that others have provided or basic  
> guesswork
> based on manufacturer datasheet info) but I'm talking about going  
> into a
> whole different realm of long exposure.
>
> Michael Wesely's work work documenting urban development such as the
> re-building of the MOMA building in NY were indeed ultra long  
> exposures and
> not time lapse. The MOMA images were 34 month exposures through 4  
> pinhole
> cameras. MOMA invited him to do this project and authorized designated
> areas for his cameras so that they could be insured the cameras  
> would not
> be disturbed during the ultra long exposures. In some of the images  
> where
> the sky is visible you can see the progression of the sun. These  
> images
> would in fact be considered Solargraphs on film I suppose. The  
> progression
> of the sun's path is continuous and you can see the changes in  
> season as
> well as when weather was clear vs overcast. It is textbook  
> Solargraphy.
> Other images do not include a view of the sun and this confirms that  
> such
> long exposures can be made without view of the sun. Remember, in my
> original post I was wondering if the extreme brightness of the sun  
> played
> some role in the exposure of paper in Solargraphy. Wesely is using  
> film I
> believe but I haven't been able to confirm that. He might have used  
> paper
> which would have made reciprocity irrelevant but the images look  
> more like
> film then paper to me.
>
> -Francesco Fragomeni
> www.francescofragomeni.com
>
>
>
>
> On Fri, Jan 20, 2012 at 5:46 AM, Diana Bloomfield <
> dhbloomfield at bellsouth.net> wrote:
>
>> Francesco,
>>
>> I've only used very long exposures with pinhole cameras as well.  Of
>> course, there are published reciprocity charts out there.  (Check  
>> Eric
>> Renner's 'Pinhole Photography: Rediscovering a Historic Technique').
>> Although his published charts include only pinhole F-stops, I still  
>> think
>> you could glean something from them.  And I do think that the  
>> information
>> that comes with film (or used to?) is fairly accurate-- at least  
>> for me.
>>
>> But from my experience, I agree with Gord here that some films  
>> "don't seem
>> to vary significantly past a certain duration of exposure."  That's
>> certainly been my experience (and not just with this high contrast  
>> film).
>>
>> I will also add that the published reciprocity charts I used never  
>> seemed
>> to offer all that much help to me.  I typically base my long  
>> exposures on
>> the type of film, the type of (pinhole) camera I'm using, and the  
>> available
>> light-- basically calculated guesswork, erring on the side of
>> over-exposure.  (Quite scientific!).  But with the right  
>> development,  I
>> never seemed to have a problem.
>>
>> Diana
>>
>>
>> On Jan 19, 2012, at 11:53 PM, Gordon J. Holtslander wrote:
>>
>> I can't offer any mathematical insights,  however the pinhole  
>> camera on
>>> film work I have done usually involves long exposures.
>>>
>>> I started doing pinhole work with large format high contrast contact
>>> printing film and processed it with Dave Soemarko's LC1 developer  
>>> mixed to
>>> minimize contrast in order to get a continuous tone negative.
>>>
>>> When used with this developer the film has an effective ASA of 1.   
>>> Shots
>>> taken outside on a cloudy day would need an exposure of 1/2 hour.   
>>> I also
>>> took a series of indoor photos where the exposure time as in the  
>>> range of 6
>>> to 8 hours.  As long as I metered accurately my exposures were  
>>> consistent
>>> regardless of the exposure time - from 15 minutes in full sun to 8  
>>> hours
>>> inside.
>>>
>>> Used in this way the film (at the time Kodak CGP) did not seem to  
>>> exhibit
>>> any reciprocity failure, or perhaps the reciprocity failure did  
>>> not vary in
>>> the range of exposure I was working with.
>>>
>>> My point is that perhaps with extremely long exposures the  
>>> sensitivity of
>>> this film is consistent, and does not vary significantly past a  
>>> certain
>>> duration of exposure.
>>>
>>> It was possible to get reciprocity compensation data for certain  
>>> film. I
>>> don't think is was calculated, but done by empirical testing of  
>>> each type
>>> of film.
>>>
>>> Try doing some empirical testing and see if your film shows a  
>>> continually
>>> increase in reciprocity failure, or if it stops or decreases after a
>>> certain.
>>>
>>> Photograph a grey scale in dim conditions and increase the  
>>> exposure time
>>> and see what effect it has.
>>>
>>> I also read that when electronic flashes were first used, some films
>>> suffered from reciprocity failure due to extremely short exposure  
>>> times.
>>>
>>> Hope this helps.
>>>
>>> Gord
>>>
>>
>> ______________________________**_________________
>> Alt-photo-process-list | http://altphotolist.org/**listinfo<http://altphotolist.org/listinfo 
>> >
>>
> _______________________________________________
> Alt-photo-process-list | http://altphotolist.org/listinfo