Newb adjusting for reciprocity, Delta 3200

[tdemmz]

Hey guys, I'm going on a trip to northern California in a couple of days, and I'll definitely be trying my hand at long-exposure photos at night. I'll be using the praised Acros 100, and Delta 3200 to see what it gives me. I'll send out the film I shoot to a lab.

For the Acros, I'm going to put my faith in Fujifilm's claims that no adjustment is needed until 120 seconds. But for the Delta 3200, I've read that Ilford's chart is quite unreliable. I did a little googling and found most information to be difficult to understand. I read "LIRF is lurking at your F-stop" and found it to be confusing just after the formula "t=tm + tc" is introduced; I have no idea how to find "a" or "b" in tc = a*(tm^b) and the charts are awkward to me.

Can somebody help me out here in solving this math dilemma, or at least provide me with their adjustments when shooting Delta 3200? Thank you.

 

[summicron1]

i have been told that delta 3200 is really 1600 or so. I have managed to make it through 45 years of shooting film without ever learning, or understanding, what those symbols you used there are and I'm not about to start now, so I leave that to others.

on a broader note, the questions you ask are going to be hard to answer -- reciprocity seems to be one of those things that is pretty situational and best resolved by experimentation. It is a shame you don't seem to have time to experiment before your trip -- shooting "must have" images, or shots that are difficult to re-shoot, is not the time to play around with unknowns.

Having said that, go by the charts for long exposures and then take a second shot with double the time. Whenever I do that both shots end up looking about the same, but it pays to be careful.

 

[dasBlute]

I'd stick with acros for night work, very low reciprocity; I'd use 3200 for handheld or street or unless you are purposefully looking for grain

 

[Xmas]

Set the meter to 1000 ISO for 3200... If you might need to wet print.

 

[RobC]

The speed you get from D3200 is very dependant on which developer you use.

EI 3200 Microphen Stock 9 mins @ 20deg C
EI 1600 DDX 1+4 18 mins @ 20 deg C
EI 1000 ID11 Stock 10.5 mins

Which combination you use depends on what you want. 1000 with ID11 will be the least grainy, 1600 with DDX a tad more grainy and 3200 in Microphen very grainy.
The above will give normal contrast curves.
Obviously you can push more if you like but I can tell you that won't achieve more speed than you can with Microphen without using some hybrid developer.

D3200 seems to create more confusion than any other film.

It quite clearly states in Ilfords own datasheet that it is an ISO 1000 speed film. If in any doubt about the developer you will use then use EI 1000.

Important note: Microphen gives a greater speed increase with D3200 than DDX does. Hence above figures. Yopu can push more with either developer but you won't get metered value in middle of curve. i.e. the more you push the lower on the curve the metered value will be and that means you are pushing the highlights more than the shadows.

 

[RobC]

I have never used reciprocity with D3200. But I do use Ilfords own reciprocity chart with Ilford films and find they work well. This does depend on what you meter for. Often at night if you meter a highlight you will find that it doesn't require any reciprocity correction. But if you then meter a shadow in the same scene it does require reciprocity correction. Well obviously if you correct for the shadow you will completely blow the highlights. Since its night you should expect shadows to be extremely dark. I meter and place exposure on a highlight (usually zone 7) which will get me the correct expsoure (with reciprocity correction if required for the highlight) for the mid to highlight values which will be the most important part of your subject. If reciprocity has kicked in for the highlight then I apply the Ilford corrections.
I never use a formula or any of the many and varied suggestions posted on the web. i.e. I only use what the manufacturer suggests but based on a highlight reading. Works for me.

YMMV

 

[Stephen Benskin]

i have been told that delta 3200 is really 1600 or so. I have managed to make it through 45 years of shooting film without ever learning, or understanding, what those symbols you used there are and I'm not about to start now, so I leave that to others.

Delta 3200 would have an ISO of around 1000 if Ilford decided to test using the ISO standard. Everything else is EI. In fact, Ilford's Delta 3200 data sheet says "has an ISO speed rating of ISO 1000 to daylight." Kodak include a statement with P3200 that it's high EIs can be applied if the user didn't mind loss of shadow detail. Which means the higher speeds aren't achieved. TMZ would have an ISO speed of around 800. Ilford says about the same thing but it's more cloaked, "It should be noted that the EI range recommended for Delta 3200 Professional is based on a practical evaluation of film speed and is not based on foot speed, as is the ISO standard." In other words, it underexposing and over developing has an acceptable look to the user, then it has a practical EI for that speed rating. It's sometimes called pushing for speed.

 

[RobC]

Delta 3200 would have an ISO of around 1000 if Ilford decided to test using the ISO standard. Everything else is EI. In fact, Ilford's Delta 3200 data sheet says "has an ISO speed rating of ISO 1000 to daylight." Kodak include a statement with P3200 that it's high EIs can be applied if the user didn't mind loss of shadow detail. Which means the higher speeds aren't achieved. TMZ would have an ISO speed of around 800. Ilford says about the same thing but it's more cloaked, "It should be noted that the EI range recommended for Delta 3200 Professional is based on a practical evaluation of film speed and is not based on foot speed, as is the ISO standard." In other words, it underexposing and over developing has an acceptable look to the user, then it has a practical EI for that speed rating. It's sometimes called pushing for speed.

Ilford did do the ISO tests and it states the ISO speed is 1000 in the Ilford datasheet. The problem is that a few people who are blinded by numbers and refuse to accept that Ilford know what they're doing keep pertpetuating wrong information about the film.The film box says EI 3200 not ISO 1000.

Fact is D3200 is a low contrast high speed film designed to be used with speed increasing / push development. Hence why it works well with DDX and Microphen to give normal contrast.
The ISO speed, as with all Ilford developers I believe, uses ID11 in the tests as submitted to ISO. Hence the ISO speed of 1000 which is slower than DDX and especially Microphen which is Ilfords maximum speed/push developer.

 

[Xmas]

Ilford did do the ISO tests and it states the ISO speed is 1000 in the Ilford datasheet. The problem is that a few people who are blinded by numbers and refuse to accept that Ilford know what they're doing keep pertpetuating wrong information about the film.The film box says EI 3200 not ISO 1000.

Fact is D3200 is a low contrast high speed film designed to be used with speed increasing / push development. Hence why it works well with DDX and Microphen to give normal contrast.
The ISO speed, as with all Ilford developers I believe, uses ID11 in the tests as submitted to ISO. Hence the ISO speed of 1000 which is slower than DDX and especially Microphen which is Ilfords maximum speed/push developer.

Hi Rob

I set my meter to 1000 and meter using my normal technique.
I've not noticed any difference between ID11, ID68 or Rodinal in speed.
I like the option of wet printing easily.
I make enough underexposed negatives by accident without doing it deliberately.
It is way easy to print an overexposed negative.

Noel

 

[RobC]

Hi Rob

I set my meter to 1000 and meter using my normal technique.
I've not noticed any difference between ID11, ID68 or Rodinal in speed.
I like the option of wet printing easily.
I make enough underexposed negatives by accident without doing it deliberately.
It is way easy to print an overexposed negative.

Noel

It won't be underexposed using the figures I gave. You get an 8 stop range black to white with spotmetered value in the middle. i.e. 4 stops either side.

Sure you can always expose it at 1000 if you want to.

 

[Stephen Benskin]

Hey guys, I'm going on a trip to northern California in a couple of days, and I'll definitely be trying my hand at long-exposure photos at night. I'll be using the praised Acros 100, and Delta 3200 to see what it gives me. I'll send out the film I shoot to a lab.

For the Acros, I'm going to put my faith in Fujifilm's claims that no adjustment is needed until 120 seconds. But for the Delta 3200, I've read that Ilford's chart is quite unreliable. I did a little googling and found most information to be difficult to understand. I read "LIRF is lurking at your F-stop" and found it to be confusing just after the formula "t=tm + tc" is introduced; I have no idea how to find "a" or "b" in tc = a*(tm^b) and the charts are awkward to me.

Can somebody help me out here in solving this math dilemma, or at least provide me with their adjustments when shooting Delta 3200? Thank you.

It would help if you defined the variables in the equation. I'd suggest using the Ilford's chart. What people may have found "unrealiable" is that they are already underrating the film and over processing when rating it at over 1000. When shooting in extreme situations, there is less latitude for mistakes.

Delta 3200 can be considered a low contrast velocity, low gamma infinity film. The contrast doesn't build very quickly and it doesn't get too contrasty with extended development. This is the ideal pushing film as it gives more time for speed to build without excessive contrast. Notice how the time / gradient curve is leveling off around 0.80. That's only around a +1 2/3 push for contrast.



One thing to remember is EI stands for exposure index. This could mean the tested speed of the film, as in following the ISO standard, to simply how the meter is set. When EI is used, it isn't necessarily the actual film speed.

 

[tdemmz]

Thank you all for the information! So here's what I think I'll do: set my camera to 1000iso, use ilford's chart for the first exposure, and then double that for a second shot. Who's with me?

Also, I'd like to repeat that I will be sending my film to a lab; I won't be able to play with different developers.

 

[RobC]

What are you going to tell the lab? Do you know what the lab are going to use to develop the film? How do you know you will need to reciprocity corrections? How can say what your corrections will be before you have got there and metered the subject?
Some labs may use Microphen others may use their standard developer for D3200 depending on what you tell them you used as EI.

Assuming you're using your in camera with averaging meter, then your metering could be all over the place depending on the subject and any lights in it or not. So it is impossible to say what corrections you should use.

 

[Lee L]

Try these numbers for a start. Based on testing of 1990's Delta 3200 by Michael Covington and published in his film astrophotography book.

Lee