BLACK MAGIC - IT'S MAGICTechnical applicationA state of the art complete modular product system of liquid photographic emulsions
Table of contents:
OverviewWant to realize your individual imagination photographically? Your photographic ideas on the most unusual materials? No problem! ROLLEI BLACK MAGIC is a unique product system which makes it possible to coat light sensitive photographic emulsions onto almost any kind of surface:
BLACK MAGIC is probably the most comprehensive product system of its kind and thus offers advantageous features:
*special hardening additive 1. Safety firstIn all areas of life, any product may be harmful if not used properly. Of course this applies also to photographic products. We at MACO care about our customers and our responsibility in regard of environmental aspects.
Therefore we have kept any potential health hazards to a minimum. However
we urge you to use appropriate caution in handling our photographic
products.
See Safety data sheets above. 2. UsageThe use of BLACK MAGIC should take place in a black & white darkroom. The graded BLACK MAGIC emulsions RBM25 may be mixed together in any ratio.
3. What do you need - a checklistDepending on your goal, you should have all necessary components at hand. If you miss an important tool or material during your work it is too late. Most items are ready available in a well equipped darkroom - but some are special and have to be organised before your coating session: Checklist:
4. How much area can be coatedWith non-absorbent materials, you can coat up to 8 m², with absorbent materials you can coat up to 4 m². In practical use, this may vary due to the thickness of the coating and the absorbent properties of the chosen material.
5. How do you store BLACK MAGIC
The liquid emulsions RBM25 and RBM33 should be stored in the refrigerator
(6°C-8°C / 40-46 F).
6. How long is the shelf lifeIf stored according to our instructions, shelf life will be one year. If you deep freeze RBM25 and RBM33 at temperatures below -10 C° / 14 F shelf life will be extended by far.
7. What type of Safelight is suitable
Keep in mind, that silver halides collect light in difference to the human eye. Therefore, it is advisable to keep safelight exposure to a minimum. In reality no safelight is really safe - it's just a matter of exposure time. We recommend to do a fogging test under your own conditions - this is especially important if you want to coat large areas or many objects. Carry out a trial coating and let it be exposed partially by your safelight at the place you want to coat all other materials. Place a black cardboard on top and move it in a way that you have an exposure bracketing of 15 minutes/ 30 minutes/ 45 minutes and so on. Develop and see whether any exposure shows a gray fogging. If this is the case move or change your safelight.
8. What different approach is recommended for each type of material to be coatedDepending on the chosen material, the thoroughness of your preparation will be decisive for your final art work. All materials have to be free from dust and grease. If in doubt clean twice - any trace of grease will lead to adhesion problems. After you have selected a material to be coated, there is a different approach for 3 main groups of materials:
How to make a baryta solution: (this step may be carried out under normal lighting conditions) Warm up 1000cc tab water until 70°-80°C and dissolve completely 40 grms of RBM41 by continuous stirring, until free of lumps. To reduce surface tension you may add a few drops of wetting agent (with bactericide and fungicide additives) to your solution, this makes it easier to evenly coat smooth /hard materials. Coat your material directly afterwards. To improve hardening of the emulsion add 20 - 50 cc of BLACK MAGIC additive RBM52 to your solution. Since you coat under normal lighting conditions even coating will be much easier. Note about hardening: You can harden indirectly by adding BLACK MAGIC additive RBM52 to the baryta solution and harden directly by adding BLACK MAGIC additive RBM52 to the light sensitive photographic emulsion (in this case, please use the photographic emulsion within 2 hours). For better adhesion of the coating and to improve mechanical resistance of the surface you may combine both methods. Furthermore, you can add BLACK MAGIC additive RBM52 directly to the developer.
9. How do you combine the modular components of the BLACK MAGIC systemThe graded BLACK MAGIC emulsion RBM25 may be mixed together in any ratio, to achieve in between grades. For a wide range of contrast control use BLACK MAGIC RBM33. For absorbent materials use BLACK MAGIC RBM41, it is a purified photo gelatin, much cleaner than gelatin for food, and add for improved mechanical resistance BLACK MAGIC ADDITIV HD RBM52 instructions at the end of this manual, due to its special formula you can add RBM52 also to the emulsion itself and to the developer. Spirit (grain alcohol) is recomended in order to get rid of bubbles which almost always occur. Add 10-20cc of it directly into the liquified emulsion (amount based on 500cc). If you have a longer coating session, you can add spirit (grain alcohol) every 20 minutes.
10. How to achieve different image tonesIf you decide to precoat your material with BLACK MAGIC RBM41, you can add water soluble photographic dyes to the solution - add as much until you have the desired tone, usually a few drops will suffice.
11. How does the liquification take placeTake out BLACK MAGIC photographic emulsion of your refrigerator and... Carry out following working steps under safelight conditions ! Warm the bottle of emulsion by immersing it in a bucket or container filled with warm water (35-40°C).
If you want to coat larger objects (e.g. ceramics, stones) you may heat them in your oven (30-40°C /86 -104F) so your emulsion won't set while you are still coating.
12. What are the different ways of coating
If you have never worked with BLACK MAGIC photographic emulsion before, you can train the coating procedure with coffee cream since this liquid has a similar viscosity. You can coat your objects different ways:
* Use only spray guns with large jet opening, an air brush is not suitable.Wear protective clothing/mask to avoid inhaling spray particles. For most applications best results will be achieved by using a brush with natural hair (e.g. Japan brush). We recommend to coat test stripes at the same time for determining the correct exposure later on. Preferably of the same material or the backside of photographic paper). Excessive emulsion may be reused immediately.
Setting stage: Cooling and setting stage follows directly after coating. In this stage the coated surface is very delicate. Setting will take about 1 to 2 hours. You can speed up setting by storing the coated materials in the refrigerator for about 30 min. To avoid unwanted exposure either use a light-tight container or unscrew the bulb of your refrigerator. Drying stage:
Now you can dry the coated materials.
13. Exposure - what do you have to considerProcedure is similar to standard photographic paper, especially if you have coated flat materials. With 3-dimensional objects close down your enlarging lens to the maximum to reach maximum depth of field. (Note that by stopping down your lens, depth of field will be 1/3 before and 2/3 behind point of focus) Hint: With cylindrical or evenly formed objects you can produce a large halftone negative (or if you wish also a graphic negative without grey values) by using lithographic film. This negative can then be laid or taped onto your coated object (e.g. a bottle or a vase) and then turn it evenly under the enlarging light - by doing so a sharp and even exposure will be a lot easier !
14. Processing - what is important for good resultsDue to the high silver content, use high energy photographic chemistry only. BLACK MAGIC will work well with most standard darkroom chemicals; however, you should keep the working solutions at a maximum temperature of of 20°C/68°F or lower, to avoid damaging the emulsion. Washing times are dependent on the coating thickness and base material. We recommend the use of a neutral or alkaline fixer such as Silvergrain Clearfix to reduce emissions and shorten washing times. Selenium toner or Agfa Sistan can be used to increase image stability and longevity. If required, a hair dryer can be used to heat dry the final result
Hints for processing
15. Notes on special aspects
|
| Result | reason | remedy |
| Bubbles in the finished picture |
heavy stirring or shaking has caused air bubbles |
avoid heavy stirring or shaking add 10 - 20 cc of spirit (grain alcohol) for 500cc Black Magic by slowly stirring |
| uneven coating |
uneven storage during setting stage and coat several layers |
level out your object |
| Emulsion take off during processing |
grease or anti-adhesion agents on your object |
thoroughly clean your object or precoat with alkyde resin paint |
17. Support
If you have questions or any proposals after reading this manual, we are happy to receive your feedback under:
| HOTLINE: ++49-40 - 237 008 - 88 |
| Fax: ++40-40 - 23 35 77 |
| E-mail: PHOTO@mahn.net |
18. Hardening instructions
A short summary of the attributes of BLACK MAGIC ADDITIVE RBM52 for liquid B&W photographic emulsions:
- specially suited for the use in combination with B&W liquid photographic emulsions.
-
hardens the photographic emulsion and improves by doing so:
- the mechanical resistance of the emulsion
- the adhesion of the emulsion on the base material
- decrease of the drying time
- new and especially easy and elegant adding to the developing bath.
- different methods for applying.
- easy takeout and convenient preparation of partial amounts because of liquid concentrate.
- no increase of processing times.
Product description / general informations:
LABOR PARTNER BLACK MAGIC ADDITIVE RBM52 is a new hardener for use in combination with liquid photographic emulsions.
By the nature of liquid photographic emulsions following problems may occur:
- „Lift off" of the emulsion during the stage of wet processing
- damages of the coating during or after wet processing
- long drying times because of manually applied coating of large thickness
The old and now superseded methods of hardening are more painstaking, need a relatively long time of duration before hardening has been achieved. Moreover they have a low efficiency.
Based on new research the use of hardening fixers sometimes mentioned in photographic literature as well as in photographic magazines has turned out to be negative in terms of washing out long term damaging thiosulphate complex as well as silver compounds.
(Even Ansel Adams warned about the use of hardening fixers as archival quality can hardly be achieved).
Moreover, even the „best" hardening fixing bath cannot by nature avoid the „Lift off" of a liquid emulsion coated object in the developer or stop bath.
LABOR PARTNER BLACK MAGIC ADDITIVE RBM52 avoids these problems, because, and this is very convenient and successful, it may already be added to the developer.
By this application method the RAPID HARDENING is of great advantage.
Field of application
BLACK MAGIC ADDITIVE RBM52 is applied within the BLACK MAGIC Systems of liquid photographic emulsions (resp. comparable emulsions of other brands).
Safety advices
BLACK MAGIC ADDITIVE RBM52 is a very acidic concentrate with a pH value of 3.
Therefore, for your own safety, please follow the given advice while working
with the concentrate.
Follow strictly the described order of preparation !
- avoid direct contact of RBM52 with (alkaline) developer concentrates, because it may cause a chemical reaction thereby possibly producing poisonous and and pungent vapors.
- avoid direct contact with other acids (vinegar-, citric acid).
- avoid also direct contact with alkaline concentrates next to developers e.g. toners.
- handling of RBM52 concentrate should be done with special care.
- photochemistry should be, as with other chemistry as well, kept out of the reach of children.
- after direct contact to the skin or eyes, flush thoroughly with water. If accidentally swallowed induce vomiting. In both cases medical assistance is recommended.
For further inquiries regarding BLACK MAGIC ADDITIVE RBM52, an EU-Safety data sheet is available.
Use / Preparation
BLACK MAGIC ADDITIVE RBM52 may be applied by using different methods:
A: Direct adding while preparing b&w paper developer working solution:
125 cc |
developer concentrate | |
| + | 825 cc |
tap water |
| + | 50 cc |
BLACK MAGIC ADDITIVE RBM52 concentrate |
| = | 1.000 cc |
working solution |
This procedure is easy to use and efficient for application purposes. It takes advantage of the
RAPID HARDENING mentioned earlier.
It should always be applied (even if other described hardening procedures are additionally used).
or:
If a precoat with BLACK MAGIC RBM41 purified photographic gelatin will be applied; an indirect hardening can be achieved (hardening by diffusion).
Just prepare a working solution of ADDITIVE RBM52 and add it to your dissolved pure gelatin solution (quantity to be added depending on prepared amount):
B: Preparation of a working solution ADDITIVE RBM52 for adding purposes:
80 cc |
distilled water | |
| + | 5 cc |
RBM52 |
| + | 15 cc |
distilled water (stir thoroughly) |
| = | 100 cc |
hardening solution ready for use |
Per 1000cc of prepared RBM41 gelatin solution add 20 - 50cc of your working solution RBM52 and mix well. Coating should take place right afterwards.
and/or:
| C: |
If a precoat with RBM41 gelatin is not applied, a direct hardening can be achieved by adding working solution RBM52 directly to the liquified (warm) BLACK MAGIC photographic emulsion. Depending on field of application and thickness of coating add between 10cc and 25cc to 500cc of liquified photographic emulsion. Careful mixing avoids drawing air into the emulsion thus preventing unwanted bubbles. |
With smooth (polished or glossy) hard and non-absorbent objects, e.g. glass
or ceramic tiles, to be coated it may be advisable to combine all 3 methods
in order to avoid adhesion difficulties:
- adding ADDITIVE RBM52 directly to the developer ("A"),
- harden indirectly ("B") and
- the direct hardening ("C").
Generally one can rely on the convenient and effective method „A" alone.
Shelf life + yield
Shelf life:
BLACK MAGIC ADDITIVE RBM52 in originally closed bottles has a shelf life of at least 1 year, once opened approx. 6 months, provided normal storage.
Prepare only as much working solution of the hardener as needed directly.
If BLACK MAGIC ADDITIVE RBM52 is used as an additive to developers, shelf life will be according to the data of the developer itself. It's shelf life, especially in used condition, can be improved by far if kept in tightly closed glass bottles.
For direct application of BLACK MAGIC ADDITIVE RBM52 in combination either with BLACK MAGIC pure photo gelatine or with BLACK MAGIC liquid photographic emulsions, the question regarding shelf life is not relevant.
Yield:
Per 500 cc concentrate BLACK MAGIC ADDITIVE RBM52 you can prepare up to 10 liters of hardening-developer working solution.
Note:
The black 300 cc bottles have a special protection sealing ring around the cap, which should be removed before unscrewing. Opening then will be easy.
StorageBLACK MAGIC HARDENER RBM52, whether in original bottles, or added to developers, or as a working solution, should be stored at room temperature.
(temperature range between min. 5°C - max. 30°C)
Black Magic Manual, © Hans O. Mahn & Co. Kg, 2000 (special revisions to this version by Digitaltruth Photo, 2007)
Errors, or omissions regarding technical progress, remain exempted