Copying B&W Negatives To Make B&W Positives

[Snapshot]

Hi All,

I have a question on copying B&W negative film to make B&W positives. Is it possible/feasible to copy a B&W negative using a slide copying setup to create a positive? The goal is to make B&W transparencies. I thought it might be possible to do so by copying a B&W negative to another negative to make a 'positive' image. I believe base fog would present itself to be a problem but are there any other factors that would prevent this from working?

Any thoughts or input?

 

[fschifano]

Instead of a slide copying attachment, you might want to consider making a contact print of the negative onto some graphic arts film. Almost non-existant base fog. Go over to Freestyle's or Ultrafine's websites and search for ortho litho film. Both firms advertise on this site. Lot's of choices and very low prices for the materials. Develop just like enlarging paper using very dilute paper developer to control contrast.

 

[Jim Noel]

I would just project the negative on lith film or TMax 100 using an enlarger set to give whatever size negative desired.. There are advantages and disadvantages to both.
Lith can be used with a red safelight, but must be developed in a very soft working developer. The results are very sharp.
TMax 100 must be used in total darkness, light source may have to be dimmed, very short exposures - but can be developed in normal film developers.

 

[Jim Noel]

SInce film developers are already softer working than paper developers, dilute film developers are best regardless of what one may read.

 

[Jordan]

I have made B&W slides using this method with great success:

(1) Load camera with Kodak 5302 "Fine Grain Release Positive" film (available from an electron-microscopy supply store like EMS for about $20 per 100-foot roll). Be careful when loading -- it doesn't have an anti-light-piping dye in it

(2) Attach slide duplicator with negative mounted in it

(3) Point camera at an evenly lit light source (like a light table) and try a few different exposures between 2 and 10 s, depending on your light source and slide duplicator

(4) Develop the 5302 in your favourite paper developer (I used working-strength Ilford Multigrade) for 3-5 minutes, then stop and fix as usual

Result: nice B&W positives, no darkroom required. You can give the resulting slides more punch by toning them in KRST if needed.

 

[gainer]

I think if you develop the copy to less than normal contrast, you will be disappointed. Normal contrast is already about 60% of what you see. Developing a copy of that to less than 60% will give you less than 36%. Usual practice is to make the gamma product somewhat greater than 1. This is what happens when you do reversal processing, which is an alternative if you do not already have the negatives.

 

[gainer]

While I was cogitating (old timer's lingo for "sleeping") Jordan told you how to do it when you do have the negatives. He can also tell you how to do reversal processing. And other things, too.

 

[Snapshot]

Thanks for your input everyone. Certainly, there is food for thought. Anyone have any success using Ilford's B&W reversal process?

 

[Konical]

Good Evening, Snapshot,

What you are suggesting is quite practical. In my view, the negative-to-positive copying approach is much preferable than messing with reversal processing. Reason #1: Reversal processing requires a special chemical kit, which, unless used regularly, will probably end up being partly wasted. Reason #2: Negative-to-positive allows for exposure bracketing when making the slides. Reason #3: Contact printing or direct reversal pretty much means 35mm only, while original negatives of any size can be used with the negative-to-positive approach. Reason #4: Negative-to-positive allows for easy cropping. Reason #5: Some control of slide contrast can be done with adjusted processing times, just as with standard film processing. Reason #6: Multiple copies, if needed, are easy to make.

Incidentally, B & W slides can also be easily made from color negatives.

Most of my experience with the negative-to-positive process came years ago, using the old Kodak High Contrast Copy film, processed in either D-19 or Dektol (can't remember the dilution, but it was probably 1:1).

(Many thanks, Jordan, for the info on Kodak Fine Grain Release Positive. I need to get some and try my hand with B & W slides again.)

Konical

 

[Jordan]

Reversal processing is certainly possible at home, but if your goal is merely to make copies of your B&W negatives for projection, the slide-duplicator technique is easier. There are a few other ways to make B&W slides -- I have them summarized in an article on my website, along with some reversal recipes and comments on the Ilford reversal process (which works, but needs modification for optimal results).

 

[Michel Hardy-Vallée]

Here's the long answer I wrote in the old articles section:
(there was a url link here which no longer exists)

Short answer: if you start from 35mm, contact print them on either 5302 or 2302, develop in Dektol stock, starting time 5mins.

The Leitz ELDIA is a great tool for doing B&W slides by contact printing, and it's the cheapest Leica you'll ever have.

 

[reggie]

I do this pretty often. I contact pring large format negatives onto ortho film. I then develop the ortho film in Dektol diluted about 1:9. I use the Dektol for one or two negatives and then throw it away. The negatives come out very very good this way.

I have recently run across a formula for ortho film that is made to develop ortho film in continuous tone just for this purpose. I have yet to try it, but I will the very next time I make some inter-positives. Here is alink to the article and formula:

http://members.aol.com/fotodave/Articles/LC-1.html

please let us know if you try this. It sounds promising.

I like using the ortho film quite a bit. It is easy to work with under safelight, very thin, no grain and it has a lot of density latitude.

You can also enlarge small negatives onto it very easily, just treat it as though it is paper.

-R

 

[Jim Noel]

LC-1 works very well. I use it for in camera negatives made on lith film.

 

[dr5chrome]

..if your goal is to produce this in your darkroom, graphic-arts film is the solution as most have mentioned. A reversal B&W process is not going to help you in this case. All you will do is create an interpositive from a negative [a negative copy]. In color there used to be VPF print film and i have seen this used successfully for B&W, though the results were not optimal.

We have had a better solution for this problem by using a film recorder. Depending on how much you want to spend the results can be just as good as the original. Today you can buy an 8K CRT film recorder for around 3500$ [with software]. if you have many images to produce this might be your best option.

dw

www.dr5.com
www.filmrecording.net

 

[Mike Wilde]

difficult is all a matter of resources

I regularly make masks to add a white text titles to photos when I am making up head shot prints for actor acqaintances from 35mm negs.

I too use 5032 fine grained positive release. It is ortho, only blue sensitive, so it can be handled under amber safelight (maybe red too -haven't tried it yet) It also has a very clear base.

I load it into my 35mm slr camera, set the shutter to B, aperture to 5.6 or so, and then mount the camera onto a tripod with the head reversed, to allow the camera to point down onto the material being shot, which in my case is a laser printer output, with 36 point text in the lower right corner.

I look through the viewfinder and adjust tripod height to have the draft untitled print fill the viewscreen. Then I lay the title sheet over it to put it in the right place to overlay the title text. Open the shutter, and give enouigh pops oin the ring flash or other falsh to get the exposure. This film has an asa of about 6, so dim ambient artificial lighting works out ok for the time the shutter is open.

I proceed to develop the film section I have just shot in the darkroom. I usually do one name per 4 frames to give me some extra film base to manipulate the film bit with without laying tongs onto the one frame I want.

First developer is D76 for pictorial contrast, or D-19 for high contrast. I add about 4g/l of thiocyanate (in my case sodium - I have it on hand) to this first developer. Then a rinse in water for a stop after the required development time (needs to be experimented with to find the right time in first dev to yield white highlights in the finished product).

Bleach in dichromate bath. Toxic, yes, but I use it many many times til it turns green and dies off, and then it goes to the hazardous waster depot.

Water rinse then clearing bath of weak sulfite. Then rinse and second developer in whatever paper developer I have at hand, rinse then fix til 2x clearing time.

Once dry I sandwich the mask in the negative carrier with neg from the head shot I producted the draft print for. The result is the black last printer text 36 point is now a black area where white text is to be printed , to come out very close to 36 point white in the final print.

To print these in 120 I use Kadalith, and if I want pictorial use, develop it in a very low contrast first developer, usally one called t/o xdr4.

 

[3Dfan]

Here's a resource you may be interested in - http://www.photosensitive.ca/wp/methods-for-producing-bw-slides