The Zone system & alternative processes

[dustym]

I have read quite a bit on other sites about negative density for alternative process. Does anybody have any insight on zone placement to achieve the higher contrast negative in order to only produce negatives for say Van dyke
rather than employing inter positive or print through methods.
Where would you place darkest shadow shadows in the zone to achieve high contrast negatives or do you just over develop say 75 % from a normal scene reading

rgds
Dusty

[Ole]

You don't want more density in the shadows, just a lot more difference between shadows and highlights.

So I expose normally, and develop more (or use a staining developer).

[Donald Miller]

As Ole said, you don't want more density. You do want more density range. Where conventional silver may require a 1.00 or 1.10 density range, you will want to be up into a density range of 1.65 and higher (depending on process). This is accomplished by developing longer along with proper exposure.

In fact the common Zone System practice of placing exposures on Zone III or even IV may be counterproductive since films, by and large, have a maximum attainable density range. These elevated exposures intrude into the attainable density range. Furthermore, not all films can attain the required density range.

[dustym]

As Ole said, you don't want more density. You do want more density range. Where conventional silver may require a 1.00 or 1.10 density range, you will want to be up into a density range of 1.65 and higher (depending on process). This is accomplished by developing longer along with proper exposure.

In fact the common Zone System practice of placing exposures on Zone III or even IV may be counterproductive since films, by and large, have a maximum attainable density range. These elevated exposures intrude into the attainable density range. Furthermore, not all films can attain the required density range.

Thanks chaps

rgds

[noseoil]

Use efke 25. tim

[ann]

i used a N+1 as a guide line for processing some negatives .

In fact i ran a series of test, from N-1 to N+2 and N+1 is working out vetry nicely .

[Ole]

I'm almost sorry to say that APX100 is possibly the best film I've ever tried for getting those ultra-long density scales for the low contrast processes.

Fortunately FP4+ is also great - as is EFKE PL25.

[Donald Miller]

Tmax 100 and 400 will both give the density ranges that you need...but be advised that Tmax 100 is useless for processes that are exposed with UV because it effectively shields UV in it's base. Beyond that Efke PL 100 will provide densities of adequate scale and I have heard that Efke 25 will too.

Ilford FP4 and HP 5 are both acknowledged to provide the scale required. Bergger BPF 200 will not provide the density range required...especially when one is needing expansion of a flat scene.

The most reliable way to determine the development time as it applies to the density range is by testing with a transmission densitometer...especially when one becomes involved with some of the more costly processes.

[donbga]

I have read quite a bit on other sites about negative density for alternative process. Does anybody have any insight on zone placement to achieve the higher contrast negative in order to only produce negatives for say Van dyke
rather than employing inter positive or print through methods.
Where would you place darkest shadow shadows in the zone to achieve high contrast negatives or do you just over develop say 75 % from a normal scene reading

rgds
Dusty

You may want to start out increasing your film development time by 40 to 60% more than what you use for silver gelatin, VDB requires a contrastier negative than say palladium.

You may also find that you do need to increase exposure a bit if you do not have adequate or pleasing shadow detail in your prints. Try 1/3 to 1/2 stop more exposure if you think you need better shadow details in your VDB prints.

Unfortunately people are often advised to make large exposure increases for alt prints which is usually not necessary.

Each alt process has it's own characteristic printing curve so some testing of one kind or another will be called for.

Good luck,

[sanking]

You may want to start out increasing your film development time by 40 to 60% more than what you use for silver gelatin, VDB requires a contrastier negative than say palladium.

You may also find that you do need to increase exposure a bit if you do not have adequate or pleasing shadow detail in your prints. Try 1/3 to 1/2 stop more exposure if you think you need better shadow details in your VDB prints.

Unfortunately people are often advised to make large exposure increases for alt prints which is usually not necessary.

Each alt process has it's own characteristic printing curve so some testing of one kind or another will be called for.

Good luck,

As Don suggests, if you do not have adequate exposure to get good shadow detail in your prints you need to expose more.

However, my experience is that it is more common to over-expose than under-expose when exposing and printing for alternative processes. The fact that you need a much higher contrast negative (requiring longer development time) can increase effective film speed by as much as a full stop. When I plan to develop negatives to a DR of 1.8 or higher I always use a meter reading that is 1.5X the nominal film speed. Although I use an incident meter and take my readings in the shadow I think it might be about equivalent to placing your shadow values on about Zone II. Remember, the additional time in the developer is going to increase shadow density.

If you place your shadows on Zone III, or Lord forbid, Zone IV, this will have negative consequences for shadow separation, especially with print out processes that are self-masking, such as Ware-Malde POP palladium, Ziatype, VDB, albumen and salted paper.

Sandy King