Support our Sponsors, they keep FADU free:   AG Photographic   Keyphoto   The Imaging Warehouse   Process Supplies   RH Designs   RK Photo   Second-hand Darkroom Supplies   Silverprint Ltd

Notices

Go Back   Film and Darkroom User > Chemistry > Manufactured brews

  ***   Click here for the FADU 2015/2014 Yearbooks   ***

Reply
 
Thread Tools Search this Thread Display Modes
  #1  
Old 16th May 2020, 12:16 PM
EdmundH EdmundH is offline
Friend
 
Join Date: Jan 2016
Location: North Norfolk
Posts: 325
Default Kodak Ektacolor confusion

I haven't done a lot of darkroom work over the last year due to work and other pressures. However I'm now ready to get the Nova tank running again, and received a box of Kodak Ektacolor RA4 developer from AG photographic this week.

This 20L kit comprises four sets of three components which each make up 5L (although I normally only mix 1L at a time. Now I have successfully used this product before, but I have just realised that I never followed the instructions properly. If you can read the attached photo of the (very minimal) instructions, it seems that the resulting mix is actually a stock solution which has to be diluted further (800ml per litre). Am I reading this correctly?

Also I'm now unclear whether starter has to be added just to the initial fill, or also to any further top-up mixture. Any advice would be appreciated.
Attached Thumbnails
Kodak.jpg  
Reply With Quote
  #2  
Old 16th May 2020, 01:57 PM
John King John King is offline
Friend
 
Join Date: Nov 2012
Location: County Durham
Posts: 2,133
Default Ra4

Hi Edmund long time no speak.

The RA4 is easy to mix by assuming the quantities of A, B and C are equal in proportion. The volume used to be printed on the sides of the bottle, at least they are on my last bottles. The small bottle 'A' holds 250cc Bottles 'B' and 'C' each hold 1 litre.

To make up one litre of prime developer with starter, use 1/5th of each bottle of the developer concentrate. The starter is different and I cannot recall how much is needed exactly but around 25cc per litre will not be far off. It isn't an exact science. As soon as you start developing, the chemical make up of the paper itself, will balance things out.

So for 1 litre of developer you need 100cc of 'B' and 'C' and 25cc of 'A' and 25cc of starter,

Fill a litre jug with around 700cc of warm water around 40 to 50 centigrade and first add the starter, then 'A' followed by the two other concentrates. The colour of the working solution will change as soon as you mix them, I think at one stage it goes greenish but as soon as you add the remainder of the water it should settle into a very pale yellow. Then top up to make the 1 litre.

The replenishment solution is the same quantities as the prime mix less the starter and still needs to be mixed at 40-50 degrees C.

Replenish at a rate of 10cc per each 8x10 or 100 cc for each 800 sq inches of paper including the sizes of test strips.

I hope that gets you going again.

Last edited by John King; 16th May 2020 at 02:06 PM.
Reply With Quote
  #3  
Old 16th May 2020, 03:24 PM
Mike O'Pray Mike O'Pray is offline
Friend
 
Join Date: Oct 2008
Location: Daventry, Northants
Posts: 7,448
Default

John, isn't that a tenth of each bottle based on your amounts in bold?

Thanks

Mike
Reply With Quote
  #4  
Old 16th May 2020, 05:43 PM
John King John King is offline
Friend
 
Join Date: Nov 2012
Location: County Durham
Posts: 2,133
Default Dilutions

Yes, my mistake the quantities should be twice that including the starter
Reply With Quote
  #5  
Old 16th May 2020, 09:08 PM
EdmundH EdmundH is offline
Friend
 
Join Date: Jan 2016
Location: North Norfolk
Posts: 325
Default

Thanks John, that clears up the question of starter and initial dilutions. However:

Referring back to the instructions on the box; if you read the lower line it definitely appears to indicate that this initial mixture needs to be diluted further. Could someone have look at the picture and confirm that I'm understanding this correctly?

I've never previously done this additional dilution, so I must have been using 20% over-concentrated developer?
Reply With Quote
  #6  
Old 16th May 2020, 09:45 PM
MartyNL's Avatar
MartyNL MartyNL is offline
Friend
 
Join Date: Sep 2010
Location: based in The Netherlands
Posts: 2,449
Default

Those instructions look terrible so I was wondering if kodaks tech pub. might be of any use?

Sorry I can't be of any greater help.
Attached Files
File Type: pdf j39.pdf (244.6 KB, 3 views)
__________________
MartyNL
Reply With Quote
  #7  
Old 17th May 2020, 09:37 AM
John King John King is offline
Friend
 
Join Date: Nov 2012
Location: County Durham
Posts: 2,133
Default

I have never diluted it further and have been using Ektacolour since 1992 (Except recently dallied with Tetenal) but will be returning asap.

The last lot of Ektacolour I had indicates on the bottles that it was made in China I wonder if something has been lost in the translation. I have come across this before. The dilutions are the same all the way through with the exception of the prime developer where there is less water because of the starter. I would just ignore this as it appears to be incorrect.


UPDATE


I have just looked at the diagramme and the 'extra' dilution is only the top up water to make the full volume. It is NOT extra dilution

Last edited by John King; 17th May 2020 at 09:41 AM.
Reply With Quote
  #8  
Old 17th May 2020, 10:15 AM
EdmundH EdmundH is offline
Friend
 
Join Date: Jan 2016
Location: North Norfolk
Posts: 325
Default

John, Thanks for the clarification. The instructions are very unclear.

One point in favour of the Tetenal RA4 kit is its relative lack of odour. I don't have a very good sense of smell, but I'm always sickened by the smell of the Kodak developer. Which is a shame, because for me, one of the attractions of B&W processing has always been the pleasant smell!
Reply With Quote
  #9  
Old 17th May 2020, 12:21 PM
Tom Kershaw Tom Kershaw is offline
Friend
 
Join Date: Mar 2009
Posts: 509
Default

Edmund,

I've been using the Tetenal RA-4 developer and have found it works very well. The instructions need reading carefully however to prevent one working with a double strength solution by accident. For my use in a Jobo drum "one shot" 200ml - for 12"x10" print, I dilute the developer 1+19.

Tom
Reply With Quote
Reply
Support our Sponsors, they keep FADU free:   AG Photographic   Keyphoto   The Imaging Warehouse   Process Supplies   RH Designs   RK Photo   Second-hand Darkroom Supplies   Silverprint Ltd

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Chemical Confusion! David Nimrod Darkroom 8 4th June 2014 03:05 PM
Free Ektacolor paper Brock Colour printing techniques 1 9th December 2013 10:37 PM
Confusion reigns or am I missing something John King Darkroom 22 23rd October 2013 05:31 PM
Using Ektacolor in bulk Bronnie Colour printing techniques 12 8th February 2010 09:13 PM
Kodak Ektacolor RA4 Bronnie Colour printing techniques 1 9th October 2009 11:16 PM


All times are GMT. The time now is 03:02 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.