Jump to content

The Leica Forum uses cookies. Read the privacy statement for more info. To remove this message, please click the button to the right:    OK, understood.

Photo
- - - - -

Dr5 reversal processing


  • Please log in to reply
9 replies to this topic

#1 astavrou

astavrou

    Neuer Benutzer

  • Members
  • Pip
  • 4 posts

Posted 12 July 2018 - 18:51

Advertisement (Gone after free registration)

Hello all,

 

Long time listener, first time caller :)

 

I was curious about your experience with this reversal process. I'm considering it, but would like to hear pro/cons and images if you have any--and if so, what film are you using? I'm thinking of shooting Rollei RPX 25 in Greece this summer. Thank you so much.

 

Alex


Edited by astavrou, 12 July 2018 - 19:22.


#2 Michael Hiles

Michael Hiles

    Erfahrener Benutzer

  • Members
  • 9,922 posts
  • LocationMontreal
  • City / Ort:Montreal

Posted 12 July 2018 - 22:27

Just curious - do you intend on projecting B&W slides?


Michael

I would like to manage to prevent people from ever seeing how a picture of mine has been done. What can it possibly matter? What I want is that the only thing emanating from my pictures should be emotion. - Pablo Picasso

#3 astavrou

astavrou

    Neuer Benutzer

  • Members
  • Pip
  • 4 posts

Posted 12 July 2018 - 23:37

Just curious - do you intend on projecting B&W slides?

No, I don't. Scanning and printing.



#4 250swb

250swb

    Sponsoring Member

  • Premium Member
  • 7,857 posts
  • LocationPeak District, United Kingdom

Posted 13 July 2018 - 07:54

As the Dr5 'film review' page suggests the speed of RPX25 stays the same as does the inherent qualities of the film I'm not sure what you gain by reversing it?



#5 astavrou

astavrou

    Neuer Benutzer

  • Members
  • Pip
  • 4 posts

Posted 13 July 2018 - 16:05

As the Dr5 'film review' page suggests the speed of RPX25 stays the same as does the inherent qualities of the film I'm not sure what you gain by reversing it?

I'm not sure either, that's why I asked the question towards folks who have used this process. It just seemed interesting to me.



#6 adan

adan

    Erfahrener Benutzer

  • Members
  • 7,560 posts
  • City / Ort:Denver

Posted 13 July 2018 - 21:17

There was a time in the early era of scanning software, when scanning a positive (color or B&W) gave better fidelity than scanning a negative and "flipping" the tones.

 

Straight out of the scanner, I got better tonalities scanning Velvia or Provia as B&W than scanning equal-speed negative film (Ilford Pan F, Delta 100), in, say, 1998. That has improved a lot for most B&W films today (less so for color neg, which still requires a bit of noodling, since the orange base mask is not always consistent - cyan highlights with some films, violent blue shadows with Ektar 100, etc). Grain tends to image a bit finer from a positive - not sure if that is due to actual finer grain, or the electronic tonal reversal needed in scanning negatives,

 

Thus there was a "boom" in direct-positive B&W products and processing around the year 2000± (Agfa Scala, Dr5). Although Kodak had made direct-positive chemical kits for decades previously (for their own Direct Positive film and later for TMax 100)

 

Generically, the usefulness of direct-positive B&W processing is for: portfolio consistency, if one is showing "slides" and wants to include both B&W and color work; for projection presentation, or, less so today, for easy of scanning. One of my grad school "student jobs" was shooting copies of photos out of books for classroom lecture slides, long before PowerPoint and digital projection, using Kodak Direct Positive film and Kodak's chems.

 

Except for those purposes, there is not much value in reversal B&W processing (a bit finer grain, perhaps), and a possible downside: clipping of either highlights or shadow detail, since a "good-looking slide" that includes both pure black and pure white may block up at either end compared to a negative that is all grays (more detail, less "pretty" until scanned).

 

Dr5 does have the ability to tweak their developer to get different color tones to the "grays" - sepia, etc. Although that also varies with the film type used. Dr5 used to have more samples of all major available films in their process - can't see the link on their site at the moment.

 

If you really want to see how they do with your film, send them a couple of test rolls to see the real thing.


  • astavrou said thank you to this

"Art is not what you see, but what you make others see." - Edgar Degas

Andy Piper
http://andrewpiperphotography.com/
http://www.coloradoseen.com/


#7 astavrou

astavrou

    Neuer Benutzer

  • Members
  • Pip
  • 4 posts

Posted 13 July 2018 - 22:42

There was a time in the early era of scanning software, when scanning a positive (color or B&W) gave better fidelity than scanning a negative and "flipping" the tones.

 

Straight out of the scanner, I got better tonalities scanning Velvia or Provia as B&W than scanning equal-speed negative film (Ilford Pan F, Delta 100), in, say, 1998. That has improved a lot for most B&W films today (less so for color neg, which still requires a bit of noodling, since the orange base mask is not always consistent - cyan highlights with some films, violent blue shadows with Ektar 100, etc). Grain tends to image a bit finer from a positive - not sure if that is due to actual finer grain, or the electronic tonal reversal needed in scanning negatives,

 

Thus there was a "boom" in direct-positive B&W products and processing around the year 2000± (Agfa Scala, Dr5). Although Kodak had made direct-positive chemical kits for decades previously (for their own Direct Positive film and later for TMax 100)

 

Generically, the usefulness of direct-positive B&W processing is for: portfolio consistency, if one is showing "slides" and wants to include both B&W and color work; for projection presentation, or, less so today, for easy of scanning. One of my grad school "student jobs" was shooting copies of photos out of books for classroom lecture slides, long before PowerPoint and digital projection, using Kodak Direct Positive film and Kodak's chems.

 

Except for those purposes, there is not much value in reversal B&W processing (a bit finer grain, perhaps), and a possible downside: clipping of either highlights or shadow detail, since a "good-looking slide" that includes both pure black and pure white may block up at either end compared to a negative that is all grays (more detail, less "pretty" until scanned).

 

Dr5 does have the ability to tweak their developer to get different color tones to the "grays" - sepia, etc. Although that also varies with the film type used. Dr5 used to have more samples of all major available films in their process - can't see the link on their site at the moment.

 

If you really want to see how they do with your film, send them a couple of test rolls to see the real thing.

Thank you so much for your response. The change in curve was one of the things I was wondering about in addition to ease of scanning. I most definitely will run test rolls, but if I don't, I'm comfortable developing films per my usual method. To be honest, I've never had any B&W positives made. My only reference is to that Scala craze in the 1990's as you pointed out (the examples looked wonderful). May I assume the film will therefore respond to highlights and shadows the same as color slide film? If that's the case, would you then expose for your most important highlight? I realize I would need to run my own test, just asking the hypothetical question.


Edited by astavrou, 13 July 2018 - 22:46.


#8 bruscwillis

bruscwillis

    Member

  • Members
  • PipPip
  • 13 posts

Posted 22 August 2018 - 19:54

I was just thinking about this Dr5 secret recipe to reverse films.. I mean, they are quite expensive. And nobody knows how they are doing it. Almost like magic. Almost anytime where you see something magic, actually it's just a simple trick. I mean, a roll of reversed HP5 is about 18 USD, right? What if they are just developing as black and white your film with a large dynamic range, then copying on another roll of HP5 and developing again with more contrast? I mean, with few bucks you can make a very nice reproduction of a negative, using the right developers. 



#9 adan

adan

    Erfahrener Benutzer

  • Members
  • 7,560 posts
  • City / Ort:Denver

Posted 23 August 2018 - 00:32

No "secret recipe" or "magic" to reverse-processing B&W film. As I said, Kodak sold kits over-the-counter to reverse process B&W films, until the market got too small. Foma still sells one.

 

All you have to do is process the negative, then bleach away that negative image with a chemical, fog the remaining unexposed (positive) silver, and re-develop. Then fix the result as normal.

 

Dr5, Kodak, Agfa Scala, Foma, Photographer's Formulary - all use the same basic process. Dr5 just has two optional developers for the second development, for neutral-gray or brown images.

 

Bleaches can be potassium dichromate + sulphur, or potassium permanganate. Kodak's kit was permanganate.

 

A whole lot cheaper, and sharper results, than making a "dupe" onto another roll of film.

 

https://www.freestyl...BSABEgJAV_D_BwE

 

https://www.freestyl...or-Fomapan-R100


  • Lukas F. and bruscwillis said thank you to this

"Art is not what you see, but what you make others see." - Edgar Degas

Andy Piper
http://andrewpiperphotography.com/
http://www.coloradoseen.com/


#10 bruscwillis

bruscwillis

    Member

  • Members
  • PipPip
  • 13 posts

Posted 23 August 2018 - 11:33

Foma kit is so expensive in US. Here, in Europe is abut 35 EUR




0 user(s) are reading this topic