Internegatives. Learning...

[lhalcong]

Ok. I think I'm on my way to understanding internegatives now. I printed a fuji Velvia slide on Kodak Portra Endura paper. It looks like a giant "negative" but on paper.

So the purpose of internegatives of course is to reverse the slide so it can be printed on negative paper, and reversed once again. Just like making multiple photocopies of an original, I'd imagine there is loss of quality throughout the process, not to mention how cumbersome it must be to get the internegative exposure right..

- What are the pros and cons of using this technique and why was it invented ?

- How was it done in the past ? And how would someone do it today without the special internegative film from Kodak ?


I'm going into two years of darkroom now, and it is still just as exciting as day one. !




Sent from my iPhone.

 

[Photo Engineer]

You print the slide onto Portra film using daylight filtration in your enlarger. My typical exposure is 1/2" at 100C, 50M.

You then pull process at 3" to reduce contrast.

The reason is that printing slides is not as accurate in tone or color reproduction. Printing negatives is better due to the long straight line of the curve.

PE

 

[jbrubaker]

In my days as a photo tech. I regularly made intenegs by projecting transparencies onto 4x5 sheets of Kodak or Fuji interneg film. Prior to digital scanning, either you made an interneg or you needed to print your transparency using a direct positive material. Since we can now scan the transparency, and make a digital print, there is really no need for internegs. I know this is an analog forum, but the scanning process is really much better at retaining all the information in the original transparency. regards ---john.

 

[flavio81]

I'd imagine there is loss of quality throughout the process,

I guess that if you use a larger format than the source (i.e. medium format for a 35mm slide), loss of quality might be minimized.

 

[flavio81]

Since we can now scan the transparency, and make a digital print, there is really no need for internegs. I know this is an analog forum, but the scanning process is really much better at retaining all the information in the original transparency. regards ---john.

For 35mm, i'm not so sure, in terms of details (resolution and sharpness). Calling Henning Serger here...
I would guess that regarding tonality, considering that there are no more interneg film available (correct me if i'm wrong), the digital system would be better.

 

[Photo Engineer]

Flavio, please see my post! Portra serves just fine as an internegative. There are small errors in the toe region of the slide, but other than that it does a fine job.

PE

 

[bvy]

I do wish we could stay on topic. Anything in the world could be slapped on a scanner and printed. There's no satisfaction for me in an inkjet print of a scanned chrome. I'd like to see the conversation and experimentation around making internegatives evolve. I think it has promise.

 

[Bill Burk]

The loss of quality comes if you think of putting 35mm Portra in your camera and shooting on a copystand using a 35mm to 35mm slide duplicator.

Once you make a 4x5 or larger internegative, you make the "generation loss" less significant, and the internegative becomes a high quality negative for making final prints.

My talent? No, but I had some 35mm slides printed large and the lab I took it to made internegatives on 4x5 - whether in a special camera with copyboard - slide duplicator - to 4x5 setup... Or if like PE said, just enlarge onto the film. It's not like you have to get a special camera in that case... You just have to get a box of film.

 

[Bill Burk]

I suffered lost quality making copy negatives from family wedding album prints... The originals were 4x5 and the prints were 8x10 and my 35mm negatives, even though on Panatomic-X, did not give me high quality negatives for making copy prints from.

I learned then, that to make internegatives, you really should make big negatives.

 

[Newt_on_Swings]

I've also had problems making 4x5 internegatives. I was trying to contact print film and retouch on the internegatives so I wouldn't mess up the originals. I always hit a barrier with contrast even when pulling. It always came out looking pretty bad. Looking back maybe I should have tried harder at it, but at the time I was pretty stressed about the photograph and ended up dropping it and using another image for the project.

 

[lhalcong]

Uhmm ? I don't have a 4x5 enlarger. So that leaves me contact printing at 8x10 as the possibly only option I think. Box of 10 sheets of 8x10 Portra runs for aprox $150. Ouch. ! Plus the purchase of a 8x10 tank. Scanning is looking more promising but I agree with bvy , I want the pleasure of producing my own analog work. My enlarger takes up to 6x9 film but I can't see myself duplicating to a 6x9 roll of film.

 

[Bill Burk]

What size enlarger have you got? Suppose it can handle 6x7, you could enlarge onto a sheet of 4x5 film but only use 6x7 image area, then cut the developed interneg to fit your negative carrier.

 

[Photo Engineer]

I don't enlarge to 4x5. I do smaller sizes, but larger than 35mm.

I might also point out that there are attachments that replace the lens on a camera and which can make very high quality internegatives. I have 2 different styles.

PE

 

[StoneNYC]

You print the slide onto Portra film using daylight filtration in your enlarger. My typical exposure is 1/2" at 100C, 50M.

You then pull process at 3" to reduce contrast.

The reason is that printing slides is not as accurate in tone or color reproduction. Printing negatives is better due to the long straight line of the curve.

PE

Ron,

For us laymen...

1/2" means? Is " seconds?
100C?
50M?

Are those color filters?

So you then pull 3 seconds? Seems too short to make a difference... So I must not be reading it right.

I thought you needed to use Tungsten films for copy work? What about using Portra100T? Or is that not made anymore?

Which Portra were you referring to? 160 or 400?

I tried to ask this at school but everyone said they hadn't done it in a decade and didn't think it was worth learning. But I want to learn just like the OP.

 

[Truzi]

Ron,

For us laymen...

1/2" means? Is " seconds?
100C?
50M?

Are those color filters?
comment
So you then pull 3 seconds? Seems too short to make a difference... So I must not be reading it right.

I thought you needed to use Tungsten films for copy work? What about using Portra100T? Or is that not made anymore?

Which Portra were you referring to? 160 or 400?

I tried to ask this at school but everyone said they hadn't done it in a decade and didn't think it was worth learning. But I want to learn just like the OP.

I think the " is minutes, while ' would be seconds. At least where the processing is concerned. Three minutes instead of three minutes and fifteen seconds (if I understand correctly).

I've no contextual knowledge of exposure to comment on that part.

 

[Photo Engineer]

It should be 3' not 3" pull. My bad.

The 100C and 50M refer to a typical enlarger CC filter pack to give the right "daylight" exposure to Portra. There is no Tungsten film.

Sorry.

PE

 

[flavio81]

Flavio, please see my post! Portra serves just fine as an internegative. There are small errors in the toe region of the slide, but other than that it does a fine job.

PE

Thanks PE. I thought that the linearlity errors were in the mid-tone region.

Stone,

PE recommended Portra 160. But IIRC both Portra 160 and 400 have similar contrast and color response.

 

[Truzi]

Oops, I got it reversed with the prime symbols in my post; that's embarrassing. Sorry.

 

[StoneNYC]

Thanks PE. I thought that the linearlity errors were in the mid-tone region.

Stone,

PE recommended Portra 160. But IIRC both Portra 160 and 400 have similar contrast and color response.

Thanks, but the times he gave would change from 160-400 so that's why I was confirming.

FWIW I find the shadows in 400 "yucky" with scanning, I haven't printed so it could be different but 160 surely is best.

Thanks!

 

[lhalcong]

I don't enlarge to 4x5. I do smaller sizes, but larger than 35mm.

I might also point out that there are attachments that replace the lens on a camera and which can make very high quality internegatives. I have 2 different styles.

PE

can you point me out to where I can find these. ? What to look for ? Used on eBay perhaps. I wouldn't know how they look like.
Thanks.

 

[Photo Engineer]

I have no photos of them and they are put away right now as I am not making any internegatives.

However, one is made by Acall. It looks like a 12" long tube with a lens mount at one end for the camera and a 35mm frame opening at the other end. This 35mm opening has an attachment for either slides in mounts or unmounted, uncut rolls. Either one can be snapped into the end and then you point the camera at a white card in sunlight and do some trial exposures to get the right "centered" result. This way BTW, you can even dupe slides although the results are not very good due to duping pos-pos systems.

There is no meter coupling, and this is the reason for trial exposures. But, once established, you can use the same exposure over and over as the aperture does not change, just the sunlight, and if you meter that you just can't go wrong.

I'll try to post a photo when I can get back into the darkroom on some regular basis. I have been quite ill lately.

PE

 

[darkroom_rookie]

Here is an example of a contact internegative. In-date Velvia 50 and its interneg on Kodak 100T dated 2002 (these were shot and contact-printed in 2012), both on the same lightbox, shot with the same digital camera:



The transparency was developed in FujiHunt Chrome6-X kit. 100T in Digibase C-41 kit (said to be re-bottled FujiHunt - has separate bleach and fix) and pulled to 2:55.

 

[darkroom_rookie]

And the scans - one from the original and two 100% details of the internegative. Velvia was scanned on an Epson flatbed, 4990 I think, and is a little more magenta than the original, which has a slight bluish-greenish colour cast, most likely from the mid-day Summer light and the tree. Interneg was drumscanned at 3000dpi on a Scanview scanner and inverted/levelled in PS:



Internegative was printed to 16x20" Ultra Endura N and the print looked surprisingly good. There were a few other from the same session which looked even better printed.

Since making these, I met a former owner of a pro lab with over a decade of experience working with internegatives. He found that tungsten films aren't as good for internegatives, as, according to him, are more contrastier than daylight films and have worse keeping properties. Judging from the grain in 100T, probably true. Also, he used Kodak Commercial Internegative film extensively and found it to be a nightmare to work with, even in-date. So I have to side with PE here, and suggest fresh Portra 160, it should be a great film for interneg work.

And a question for PE - is there any advantage to using 80A or 80B filters in the light path (in a negative carrier) over using enlarger's filtration? Even more detailed, any difference if the filters used are resin, gel or glass?

Thanks.

Marin

 

[Photo Engineer]

Filtration is filtration if it gives a neutral balance with the light source you are using. Use what works for you. My filtration is unique to my enlarger just as yours will be.

And, very nice results!

PE

 

[darkroom_rookie]

Thanks, they were indeed something of a revelation. In fact, I have since done more contact printing than any other darkroom printing technique, both colour and black&white.