Ilford Delta 100 Recipricol failure

Asha

Asha

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Asha
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Can anyone enlighten me as to the times for exposing Ilford Delta 100 for over a minute?

I have a potential shot which will require 64 seconds exposure ......the Ilford pdf doesn't state times in excess of 30 secs

I could shoot the frame on fomapan if I want to sit around for near on 20 mins!
 
64^1.48=471.136sec

64 is measured exposure in seconds
1.48 is Ilfords coefficient
471.136 is corrected exposure

I'd gone with a straight 10 in the field, forgoing science and sense but you could bracket ??
 
joxby said:
64^1.48=471.136sec

64 is measured exposure in seconds
1.48 is Ilfords coefficient
471.136 is corrected exposure

I'd gone with a straight 10 in the field, forgoing science and sense but you could bracket ??
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Bracket? Bracket?????? did that man dare say bracket to a filmie:mad::D

OK so I could but on 4x5 ( even fairly cheap b&w), I aint shooting 3 frames just for the sake of it.

I'll try your calculation, if anything I may open up an additional stop even if I reduce the developing time to keep hold of the highlights.

If it works then ace, if not I'll have a negative and results to assess to hopefully nail the exposure second time around.

It's a local scene so not like it's going anywhere;)
 
Do ya know, I'm not sure it matters a lot when you get to exposures of this length, the law of diminishing returns an all that.

If you shot it at 7.85 minutes and it came back under, I wouldn't be surprised
If you shot it at 10 and it hardly looked any different I wouldn't be surprised
Equally, if the both came back fine....yeah......me = not surprised

Its a bit of a suck it and see to some extent


I like that...:D
 
joxby said:
Do ya know, I'm not sure it matters a lot when you get to exposures of this length, the law of diminishing returns an all that.

If you shot it at 7.85 minutes and it came back under, I wouldn't be surprised
If you shot it at 10 and it hardly looked any different I wouldn't be surprised
Equally, if the both came back fine....yeah......me = not surprised

Its a bit of a suck it and see to some extent


I like that...:D
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Yeah the longer the exposure, the less differences in the actual luminosity on the negative ......for instanceif I use fomapan, the required time is 18 minutes for a 64 second exposure but I bet if I went for a snack and left the shutter open for an hour, there would be little difference overall in brightness.

.If upon my return the camera had disappeared ....I wouldn't be surprised either:D
 
I think your safe there, peeps don't want film cameras with light leaks and gunky seals *perception*, to pinch one with Dutch Elm disease would serve em right anyway....:D
 
H'mm why can't you buy the film in 35mm, then bracket your shots (say for six time exposures), then put the camera in a changing bag snip off the film then dev that strip in your soup... after, just trim the leader and that would be ready to use for the next test shots. So for 24 exp film you would have say three uses for testing. (y)
 
excalibur2 said:
H'mm why can't you buy the film in 35mm, then bracket your shots (say for six time exposures), then put the camera in a changing bag snip off the film then dev that strip in your soup... after, just trim the leader and that would be ready to use for the next test shots. So for 24 exp film you would have say three uses for testing. (y)
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It's an option Bri, but a bit of a faff tbh......If i'm going to take time out to do all that then return to the location with LF kit to get the shot that I want then I may as well shoot the one LF frame on fomapan for 18 minutes and be done.
 
Asha said:
It's an option Bri, but a bit of a faff tbh......If i'm going to take time out to do all that then return to the location with LF kit to get the shot that I want then I may as well shoot the one LF frame on fomapan for 18 minutes and be done.
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Will the moon be out as I've got shots that turn a scene nearly to day light @ 45 sec for 200 ISO and the colours were there as well.
 
Or just shoot it on acros and not even worry in the least about reciprocity! Happy to send you a few sheets of 5x4 if you're interested?
 
Woodsy said:
Or just shoot it on acros and not even worry in the least about reciprocity! Happy to send you a few sheets of 5x4 if you're interested?
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What a guy!;)(y)

It's to hope that your British 5x4 sheets fit our European 4x5 DD holders:D:D
 
No probs. I'm in San fransisco at the moment on a conference, so won't be able to send it for a while. Will keep you posted, so to speak :)

Also, should there be a realistic option of retaining EU citizenship after this clown show, I'll be first in line, so I'm pretty sure my DDSs will be European standard as well ;) :D
 
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Woodsy said:
No probs. I'm in San fransisco at the moment on a conference, so won't be able to send it for a while. Will keep you posted, so to speak :)

Also, should there be a realistic option of retaining EU citizenship after this clown show, I'll be first in line, so I'm pretty sure my DDSs will be European standard as well ;) :D
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Placedropper...... get you all up in that San Fransisco. :D
 
It's really not all that tbh mate. On the grand scale of conference locations, SF barely scrapes a 3/10 for me. I've been to one before where walking out of the conference centre, if indeed it can even be called that on account of being essentially one lecture theatre, presented you with Mont Blanc front and centre. This place is noisy, smelly and boring.
 
Woodsy said:
You spelt 'France' incorrectly...

:D:D
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I know, I know, but as a resident, one has to be discreet ( awaits visit from Gendarmerie with deportation order:confused:) :D
 
Woodsy said:
It's really not all that tbh mate. On the grand scale of conference locations, SF barely scrapes a 3/10 for me. I've been to one before where walking out of the conference centre, if indeed it can even be called that on account of being essentially one lecture theatre, presented you with Mont Blanc front and centre. This place is noisy, smelly and boring.
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Sounds just like my office :D
 
Asha said:
I know, I know, but as a resident, one has to be discreet ( awaits visit from Gendarmerie with deportation order:confused:) :D
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It's only a matter of time.
 
Woodsy said:
No probs. I'm in San fransisco at the moment on a conference, so won't be able to send it for a while...
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Some nice photo opps in and around SF if you've got an extra day or so, even an afternoon...
 
Asha said:
I know, I know, but as a resident, one has to be discreet ( awaits visit from Gendarmerie with deportation order:confused:) :D
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Can't you get dual nationality as you have lived in France for quite a while?
 
There are smartphone apps that allow you to calculate exposure times for reciprocity.

An Android one called Reciprocity seems to be the most accurate.
 
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excalibur2 said:
Can't you get dual nationality as you have lived in France for quite a while?
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Possibly, i'm not sure tbh.
There may be some strange French initiation process to go through for it......the mind boggles at what that may involve:runaway::D
 
Parlour???? s it still the 1960's in your head. We have a lounge and a study (but yes it does smell, a bit) :D
 
Andysnap said:
Parlour???? s it still the 1960's in your head.
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In my head was "Brothel":naughty: :D but I was attempting to be polite about it,......... for Janets sake not yours.:p:exit::D

..
 
Since when were parlour and brothel interchangeable?
 
donut said:
you seem to know a lot about theses places Andy ,,,,,,
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Rigorous intellectual study young Andrew, it means I know many things about many unsavoury places. :D
 
If I may hijack this thread a little - I shot some Portra 400 at 200 speed by mistake. Should I tell Filmdev to pull the film when they develop it, or will it not really matter?
 
mothdust said:
If I may hijack this thread a little - I shot some Portra 400 at 200 speed by mistake. Should I tell Filmdev to pull the film when they develop it, or will it not really matter?
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:bat: How dare you hijack:bat::D

Imo you could have shot it at 50 and the standard C-41 developing time would be fine.......The lattitude, on most colour negative film is more than capable to stand over exposure by at least a couple of stops(y)......fortuanetly so as I've made similar errors many times:rolleyes::D
 
mothdust said:
If I may hijack this thread a little - I shot some Portra 400 at 200 speed by mistake. Should I tell Filmdev to pull the film when they develop it, or will it not really matter?
Click to expand...

There's fairly often advice to over-expose colour negative film by a stop as a matter of course; I usually over-expose by a bit less than that, so shoot at 250 or 320, then get standard dev. Seems to work out fine.
 
Asha said:
Can anyone enlighten me as to the times for exposing Ilford Delta 100 for over a minute?

I have a potential shot which will require 64 seconds exposure ......the Ilford pdf doesn't state times in excess of 30 secs

I could shoot the frame on fomapan if I want to sit around for near on 20 mins!
Click to expand...

I just remembered (as I went out last night for some night shooting) that @steveo_mcg send me his exposure guidelines for night shooting, which includes "actual" times for Delta 100, presumably from his own testing. The key times are (meter vs actual):

60 to 93 secs
120 to 3:50
240 to 8:00
480 to 16:30
960 to 33:00 minutes

So that first time is a lot less than the time of 470 seconds that @joxby calculated for a 64 second exposure!
 
an1uk said:
There are smartphone apps that allow you to calculate exposure times for reciprocity.

An Android one called Reciprocity seems to be the most accurate.
Click to expand...

I've just downloaded this one, and I'm very confused about how it should work. The list of films covered is not huge (doesn't include Delta 400, for example). I've just put in Tri-X 400. I can choose a filter factor (chose 1) and a bellows extension (presumably relevant to LF only). Then I can choose an exposure time. I chose 8 seconds, and hit Calculate... nothing happens, AFAICS! Ooo, just found a little tick box down at the bottom "Prefer the Bond/Garner/Reeves data". Checking it doesn't seem to make any difference...

(If it's relevant, this is on a Samsung Galaxy S3 Mini, which does NOT appear to have working light meter capabilities.)
 
I've got that as well Chris and I really don't understand it at all. Where's @steveo_mcg when you need him? :)
 
Looks like this on my phone. Before it shows the time there's a note saying to hit calculate. Maybe send a note to the developer via Google Play. There's another app but that seems to make a guess based on extrapolating values.
Screenshot_2017-02-17-10-26-59-044.png
 
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