Question about Cameras

3 Answers

Need yellow dye for one step past traditional developing process.

My company develops its own photos for use in and for vision screening instruments that are sold all over the world. Once the process (using Ilford MGIV FB paper and Ilford chemicals) is complete, those photos that need yellow over white are dipped into auramine 130% yellow dye until they are the correct color and then rinsed one more time. This process has been used since the late 1940's.

The dye is very difficult to obtain and has, we are now told, some unfavorable qualities. I am looking for a safe, easy-to-purchase, quality dye to replace the old product, and one that will work well with the Ilford paper and chemicals. The dye must also have a long life without fading, just as the cartridge inks for most color printers have now.

Do you have any suggestions? Please!

Judy for Keystone View

Posted by on

  • judy296 Nov 20, 2008

    Dye manufacturers have been contacted. I am looking for an alternative to the previously-used dye. I apologize if I did not make that clear in the original posting.

×

Ad

3 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Cameras Master
  • 4,806 Answers

Try here also:

http://www.tradekey.com/ks-auramine-o/

regards and good luck

Posted on Nov 20, 2008

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 685 Answers

Http://www.freepatentsonline.com/4121932.html try this site

Posted on Nov 20, 2008

×

Ad
  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Sergeant:

    An expert that has over 500 points.

  • Expert
  • 276 Answers

Contacting a dye manufacture in your area or a regitered company of making dye and asking them to make a dye of exactly what type you required can be made.

Posted on Nov 20, 2008

×

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

What is Spiritual development. How can I develop?


Spiritual development is the process of becoming fit for a higher level in the spirit world. There are three areas of spiritual learning: skills, beliefs, and evolution.
Yes, it is possible to develop spiritual development strategy. For this, you need proper guidance and practice.

To develop spiritual strategy I suggest hermetik academy, this academy provides good knowledge about life, *****, ghost, God western tradition, spiritual and much more. I have learned a lot from this academy. They have varieties of plan with a very common charge.
spiritual-journey-2cygs5gwamm35wubvufr5d1r-3-0.jpg

Dec 26, 2017 | Computers & Internet

19 Answers

Can anyone recommend me a professional app developer of Australia?


Well you can find many best suited mobile app developer on research platform like clutch.co and Extract.co. However, I would like to suggest Octal IT solution as our system supports progressive mobile app development and swift prototyping that enable you for fast launching of the product in the market.

https://www.octalsoftware.com/mobile-app-development

Apr 17, 2014 | iPhone Apps

1 Answer

Pictures


It's quite complicated to explain in detail, and there are a number of different processes, but I can start by saying how the essential chemistry of B&W processing works.

A film emulsion contains tiny crystals of a silver halide (Silver chloride, bromide etc.) contained in a layer of gelatin, coated on a plastic backing. Silver halides are sensitive to light.

There are other layers such as an anti-reflection layer behind the light sensitive layer to prevent light being scattered back to produce a 'halo' around bright areas, (Anti-halation layer) and a scratch resistant layer on the front.

Additionally dye chemicals are added which enhance the halides sensitivity to red light, to which otherwise it would be insensitive. These are known as dye sensitisers.

Only imprefections in the crystals are actually sensitive, as these contain silver ions which are not fully bound to the halogen. When a photon interacts with the crystal near the sensitve site an electron is released which can reduce the ion to a single atom of silver.

These single atoms ar enot enough to produce a visible image, but comprise a latent image within the emulsion. In order to make the latent image visible we must amplify the latent image in some way. This is done chemically by a process known as development.

There are a number of chemicals formulations which can be used as developers (including urine!), but all are chemical reducing agents. (Opposite of oxidising agents.) These convert the silver halide to metallic silver.

It so happens that for many reducing agents metallic silver acts as a catalyst, so where there is silver the reaction proceeds faster than where there is not. Of course as more silver is produced the greater the catalytic action, so the develoment process accellerated as it progesses.

This forms clumps of silver around the original silver atoms. These clumps consist of very small grains of silver, finer than any powder and these appear black. These form a negative image. (Black where light fell on the film.)

(These tiny grains are not what photgraphers refer to as 'grain'. In fact the 'grain' in a photograph is more to do with the distribution of development sites, and the random nature of the arrival of individual photons.)

Most developers are realtively benign chemicals but some are toxic and carcinogenic. These are not used much these days but are still availble.

Unfortunatley this is quite a slow process, and there is a tendency to also reduce unexposed halides somewhat. This produces an overall 'fog' to the immage. To minimise this and speed the process up an accellerator is usally added.

Accellerators are alkalis. Some formulas use quite strong alkalis like sodium hydroxide, but others use rather innoccuos substances like borax.

Development continues until the developing chemical is removed or the chemicals are exhausted. If the film is developed too much than the silver clumps begin to overlap and you get a completly black area. Further development does not make those areas any blacker even if more silver is produced!


This process is of course conducted entirely in darkness.

Most formulations use both developer and acellerator together, but sometimes these are used separatley to give better controll of the negative density. Here the emulsion is soaked in the developer, and transferred to the accellerator bath. This limits the amount of developer in the negative so heavily exposed areas do not develop as much. This allow a scene with a wider range of brightness to be recorded.

(Note that the film itself can record a much wider range in the latent image, than can be developed.)

Normally development is stopped by immersing the film in an acidic bath, which reacts with the accellerator as well as washing away developer.

The anti-halation layer dyes are usually washed out during develpment.

Of course this still leaves undeveloped silver halides in the emulsion. These are removed by fixing the image.

This is necesary for two reasons. First in a film the halide crystals have a whilte milky appearance. You need light to shine through a film duing enlargement, so that's no good. Alxo the halide will eventually turn black on exposure to light.

Fixing the image usually is a matter of washing the negative in a soultion of sodium thiosuphate. (Comonly called 'hypo'.) Silver halides are only very poorly soluble in water, but sodium thiosulhpates affinity for soft metal ions overcomes this reaction with the silver, to produce sodium halide. If this is silver chloride you get salt!)

To get a print, you expose paper treated on one surface with an emulsion, to a projected image of the enlarger and develop that in a similar way.

So there you have it. Color is a bit more complicated involving layer with different sesitivity to colored light, and dyes which are produced by the action of delvelopers.

For more details start with http://en.wikipedia.org/wiki/Photography

Jan 13, 2009 | Fuji Endeavor 200ix Zoom APS Point and...

Not finding what you are looking for?
Cameras Logo

Related Topics:

31 people viewed this question

Ask a Question

Usually answered in minutes!

Top Cameras Experts

Donald DCruz
Donald DCruz

Level 3 Expert

17130 Answers

Marvin
Marvin

Level 3 Expert

81400 Answers

Brad Brown

Level 3 Expert

17441 Answers

Are you a Camera Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...