Later E-100 Reciprocity

[Trail Images]

I'm sure this has been discussed but my searching here did not provide any discussions on the later E-100 Ektachrome reciprocity that I could find.
I've read where the first 10 seconds are not an issue. As a very long time Velvia 50 user I had made up a reciprocity cheat sheet years ago. Used the stuff for so long I memorized those time add on numbers. Which were required after 4 seconds. I think I read where Provia was as high as 3 minutes before failure started? Seems very high if so.
Anyway, does anyone have a cheat sheet of time additions for the later E-100?......thank you in advance.

 

[MattKing]

I too have found nothing about reciprocity failure with the new Ektachrome. The background information I've received about the changes that were included when it was recently re-engineered don't include anything in reference to reciprocity. Some of those changes were made necessary by changes in availability of constituent chemicals from 3rd parties, and of course the use of the Estar base is important because of the associated changes required in the emulsion.
The datasheet itself states that no reciprocity correction is needed for exposures up to 10 seconds.
I'll be watching this thread with interest.

 

[Trail Images]

I too have found nothing about reciprocity failure with the new Ektachrome. The background information I've received about the changes that were included when it was recently re-engineered don't include anything in reference to reciprocity. Some of those changes were made necessary by changes in availability of constituent chemicals from 3rd parties, and of course the use of the Estar base is important because of the associated changes required in the emulsion.
The datasheet itself states that no reciprocity correction is needed for exposures up to 10 seconds.
I'll be watching this thread with interest.

Thank you, Matt. The scarcity of V-50 after 30 plus years usage is forcing me to expand into other options. The 10 seconds is what I found also. Which is not bad when I'm use to 4 seconds. However, as I ALWAYS photograph in predawn & post sunset V-50 reciprocity was always an issue. I have one 4x5 image from the eastern sierras years ago that was 8 minutes on the original V-50.
I did send an email to Kodak-Alaris a couple weeks ago and heard crickets back.

 

[MattKing]

Kodak - either Eastman or Alaris - has always been reluctant to provide information on reciprocity failure outside the range specified in the datasheets. I expect that may be due to how subjective the evaluation is in that circumstance - due to the changed contrast one encounters arising from the fact that highlights may be affected by no reciprocity failure while shadows may be affected by a lot.
I'll try a flyer with another source - but no promises.

 

[Trail Images]

I'll try a flyer with another source - but no promises.

No worries at all Matt. Heck, all we can do is try to find someone who has worked things out. In fact, the chart I made up for V-50 years ago was taken from the Ken Rockwell site when he was into Velvia 50 usage. Although I still carry it I've memorized most of those numbers of normal usage of up to about 3 minutes.

 

[MattKing]

This site includes Ektachrome 100 in the list of films:
https://www.denisolivier.com/long-exposure-calculator/en/
I've not used it, but it seems interesting.

 

[Trail Images]

This site includes Ektachrome 100 in the list of films:
https://www.denisolivier.com/long-exposure-calculator/en/
I've not used it, but it seems interesting.

Thank you for sharing this Matt. I will play around with it tomorrow.

 

[MattKing]

I sent an enquiry to Denis Olivier at that site. He got back to me and confirmed that it was the new, current Ektachrome listed, that he had used that film and the calculator, and the results were perfect - for him.
Another bookmark for the library
I still have another enquiry out there, but progress has been made - thanks again for starting the thread.

 

[Trail Images]

I sent an enquiry to Denis Olivier at that site. He got back to me and confirmed that it was the new, current Ektachrome listed, that he had used that film and the calculator, and the results were perfect - for him.
Another bookmark for the library
I still have another enquiry out there, but progress has been made - thanks again for starting the thread.

Thank you for this follow up info, Matt. You've really provided some excellent information and now backed up by Denis' actually usage of the later E-100 too. I'm feeling much better about my move toward the E-100 usage overall. I've shot two rolls of 120 so far but have not processed them yet. I also have a couple of boxes of 4x5 as well. My overall long term need was due to the apparent impending demise of Velvia 50 in all LF sizes......


FYI: I played around with the calculator knowing the Velvia 50 reciprocity numbers and it is right on. So, I'll make another chart up for field usage for the E-100. I may not need it as much after all the 50 had a lousy reciprocity factor plus the stop slower than the 100 too. But it will be a sure help when needed in low light.......

 

[Alan Edward Klein]

Kodak Alaris just advised me the following: no compensation is required for EKTACHROME E100 for exposures of up to 10 secs. For exposures between 20 and 40 seconds he recommends adding ½ stop of exposure as a good starting point. For critical applications, make tests under your conditions.

He didn't say anything about any other published data.

 

[Trail Images]

Kodak Alaris just advised me the following: no compensation is required for EKTACHROME E100 for exposures of up to 10 secs. For exposures between 20 and 40 seconds he recommends adding ½ stop of exposure as a good starting point. For critical applications, make tests under your conditions.

He didn't say anything about any other published data.

Thanks Alan. I have been playing around with the calculator and it also seems to be a good item to test with. I base that on the fact while testing it with the Velvia 50 it was almost spot on with my many year cheat sheet I've used. I will also say that I played around with Provia and was truly surprised at that apparently not having compensations needed until between 2 to 4 minutes. I'd heard Ben Horne say upwards of 3 minutes. Quite impressive to say the lest.

 

[Denis OLIVIER]

Hello here, thank you for your interest
As stated, I used data from Kodak official source, applied curve computing with polynomial regression. I've done it on nov 2021.
Here are some results with it https://www.denisolivier.com/artwork/search/?q=e100 (converted to B&W).
Knowing me, I used exposure ranges from 2+ to 6+ minutes.

 

[Trail Images]

Hello here, thank you for your interest
As stated, I used data from Kodak official source, applied curve computing with polynomial regression. I've done it on nov 2021.
Here are some results with it https://www.denisolivier.com/artwork/search/?q=e100
Knowing me, I used exposure ranges from 2+ to 6+ minutes.

View attachment 314713

Hello Denis. Thank you for your post here. I'll admit I've not used any Ektachrome of any type since my military days in the late 60's. With that said the three e100 photos you have linked are B&W. Were those conversions from the Ektachrome color transparencies or was the link to some of your other fine art scenes?
Although the claim seems to be that E-100 needs compensation after 10 seconds using the calculator looked like it did not start until almost 30 seconds. In comparison to the Velvia 50 and my long time usage the calculator seemed spot on starting at the very low 4 seconds. What was a real surprise was the Provia 100 which was as high as almost 3 minutes. Which also seemed spot on with a comment I saw from Ben Horne sometime back now.

 

[Alan Edward Klein]

Thanks Alan. I have been playing around with the calculator and it also seems to be a good item to test with. I base that on the fact while testing it with the Velvia 50 it was almost spot on with my many year cheat sheet I've used. I will also say that I played around with Provia and was truly surprised at that apparently not having compensations needed until between 2 to 4 minutes. I'd heard Ben Horne say upwards of 3 minutes. Quite impressive to say the lest.

Are your results for Velvia 50 the same as the published data in the product sheet? If different, what times do you use?

 

[Denis OLIVIER]

Thank you for your feedbacks. The images linked are B&W converted.
The sources for Velvia 50 was a mix of official (forgetting the color compensating filters) and web sources.

 

[Trail Images]

Are your results for Velvia 50 the same as the published data in the product sheet? If different, what times do you use?

Alan, here is the cheat sheet I made up MANY years ago now. As I recall it was information I got off the Ken Rockwell site back in the early days of the original V-50. Most recent years I can't recall needing to correct beyond 1 minute.


Reciprocity Velvia 50
metered : corrected
4 sec > 5 sec
8 sec > 12 sec
10 sec > 16 sec
12 sec > 19 sec
16 sec > 28 sec
20 sec > 39 sec
25 sec > 49 sec
30 sec > 1 min
32 sec > 1 min 6 sec
40 sec > 1 min 28 sec
50 sec > 1 min 56 sec
1 min > 2 min 30 sec
1 min 4 sec > 2 min 38 sec
2 min > 4 min 50 sec
4 min > 10 min
6 min > 15 min
10 min > 25 min
15 min > 37 min
20 min > 50 min
30 min > 1 h 14 min
1 h > 2 h 30 min

 

[MattKing]

I've heard back from another source.
There is a reason why Kodak (neither Eastman, nor Alaris) never reports reciprocity failure data past 10 seconds of exposure. That reason is that all such Kodak data is based strictly on sensitometric measurements, and there are not in existence any sensitometers - old or current - that reliably and consistently supply light at-the-film that is sufficiently low to emulate those conditions.
Which means that all such data past that 10 second threshold must be based on the sort of real world testing and subjective evaluation that individual photographers often undertake. Neither of the Kodaks have gathered that sort of data. Ilford/Harman apparently have.

 

[Trail Images]

based on the sort of real world testing and subjective evaluation that individual photographers often undertake

Exactly, Matt.

Yes, not every calculation is the silver bullet so to speak. But some of the ideas as provided support more at this time than a SWAG. Especially for someone like me that MUST try to narrow the chances of lost exposures. I've had that success with fickle V-50 and will get there on the E-100 at some point too.

 

[Alan Edward Klein]

Alan, here is the cheat sheet I made up MANY years ago now. As I recall it was information I got off the Ken Rockwell site back in the early days of the original V-50. Most recent years I can't recall needing to correct beyond 1 minute.


Reciprocity Velvia 50
metered : corrected
4 sec > 5 sec
8 sec > 12 sec
10 sec > 16 sec
12 sec > 19 sec
16 sec > 28 sec
20 sec > 39 sec
25 sec > 49 sec
30 sec > 1 min
32 sec > 1 min 6 sec
40 sec > 1 min 28 sec
50 sec > 1 min 56 sec
1 min > 2 min 30 sec
1 min 4 sec > 2 min 38 sec
2 min > 4 min 50 sec
4 min > 10 min
6 min > 15 min
10 min > 25 min
15 min > 37 min
20 min > 50 min
30 min > 1 h 14 min
1 h > 2 h 30 min

Thanks for the info. Are these from the older Velvia 50 emulsions? How do these match up with Fuji recommendation for their latest Velvia 50?

 

[Trail Images]

Thanks for the info. Are these from the older Velvia 50 emulsions? How do these match up with Fuji recommendation for their latest Velvia 50?

Alan, I have used the same chart for both releases and can only say it seems to work well from my perspective. I never changed my field procedures between the two releases.

 

[Alan Edward Klein]

Ok thanks.

 

[Trail Images]

I finally heard back from Kodak - Alaris. A Thomas Mooney sent this email update.

Thanks for contacting Kodak Alaris
As you’ve noted, no compensation is required for EKTACHROME E100 for exposures of up to 10 secs. For exposures between 20 and 40 seconds I recommend adding ½ stop of exposure as a good starting point. For critical applications, make tests under your conditions.


Hope this helps,

 

[MattKing]

Thomas J. Mooney is the "Film Capture Business Manager" at Kodak Alaris, and has served as an excellent contact person over the years for a number of Kodak film related issues.

 

[brbo]

I've heard back from another source.
There is a reason why Kodak (neither Eastman, nor Alaris) never reports reciprocity failure data past 10 seconds of exposure. That reason is that all such Kodak data is based strictly on sensitometric measurements, and there are not in existence any sensitometers - old or current - that reliably and consistently supply light at-the-film that is sufficiently low to emulate those conditions.

Can someone explain this or try to explain what all this means? Sensitometers emitting light? At-the-film? What would non-sensitometric measurement (that other manufacturers are apparently using) look like...?

 

[MattKing]

Sensitometers have a calibrated light source in them. They expose film to a very precise amount of light, which permits a very accurate measurement of the film's response to that light.
The existing sensitometers - old and new - can't reliably and consistently expose film to the extremely low amounts of light that film is exposed to when light is so low as to require very long exposure times. The bulbs in them plus the modifiers built in them don't reliably and consistently go that low.
So instead, the only existing option is to do practical trials and come to conclusions about how the results "look".
That is a fairly subjective procedure, and gives results inconsistent from the data that one finds usually in a Kodak datasheet.
It might be possible to design and build an entirely new type of sensitometer that could supply those very, very low light levels. There has never been a business case for that for Kodak, because of the relatively small use of most films in those low, low, light circumstances.
Apparently they didn't even do that work when they were doing special large runs of film for astro-photography purposes, and their research and development dollars now are much more limited than back then.