wet mounting in a glass carrier

[jarred_mccaffrey]

Has anyone tried wet mounting negatives in a glass carrier for enlarging? As far as I understand, in the *gasp* digital world wet mounting negatives is standard practice for the highest quality scanning. Among many benefits it virtually eliminates dust problems, eliminates newton rings, confirms flat registration of the negative, and leads to a sharper, truer contrast read of the negative probably by somehow reducing spurious and imperfect light reflection/refraction (I think this has something to do with the perfect surfaces created by the mounting fluid and the glass).

Also, I haven't confirmed yet, but I believe it may slightly change the working density of the negative by swelling the emulsion and thus spreading the grain. This is the same effect that we see in a glistening wet print (which later dries down to something different than what we expected ;-) ). I'm not sure if this is a proportional, linear, or subproportional density change, but it might prove to be a useful tool for the printer's toolbox.

Anyone tried this? Any thoughts/experiences?

 

[David H. Bebbington]

It has always been standard practice to coat badly scratched negatives with glycerine and sandwich them between 2 pieces of glass, so the idea will certainly work in theory, it's just rather messy! The trend with scanners (Imacon Flextight) is to arc the scanned material for flatness rather than use liquid, simply to avoid cleaning afterwards.

Regards,

David

 

[L Gebhardt]

I have not tried this in an enlarger, but I bet it would give excellent results. If you use the Kami mouting fluid there should be almost no clean up as it evaporates completly. You would need to tape all the edges though to keep the fuid there. Next time I have a badly curled negative I will try this.

 

[Claire Senft]

Oiling negatives

I have some experience in oiling negatives. My results are mixed. All my experience is with 35mm. I have used both Kami SMF 2001 and Dow Corning 200 viscosity 100. The reason given for oiling negatives is varied. One source says that it changes the refraction index of the gelatin to match air or glass. The other opinion is that it changes the refraction of the air to match glass. I have no idea which opinion is correct. In the scanning industry the Kami fluid is used. The Dow Corning 200 fluid...viscosity 100 is the choice of Bob Pace. When I use the Kami, I get spots that have dried and this shows on the print. When I use the Dow Corning fluid...viscosity 100 I am always left with at least one tiny bubble on the negative. If you ever desire to see how sharp a circle can be on a print this will show you. The Kami is to be used with a special and pricey tape. This tape will not turn into goo as will other tapes when exposed to the Kami fluid. When you are done the negative can be lightly wiped with a Pec pad. If you use the Dow Corning 200 Fluid..viscosity 100 the reccomended cleaning is to dip the negative in three sequential baths of film cleaner and to hang up to dry. The negatives are handled with a tweezer.
If you have a negative that is used with either of theses fluids any marks or imbedded dust will most likely disappear.

For me this has been a technique that I have yet to master.

The fact that a printer of Bob Paces caliber recommends the Dow Corning 200 Fluid...viscosity 100 tells me right off the bat that it is capable of working well. I have used this in my Condit pin registered oil immersion carrier. I also have a matching punch and pin glasses..

 

[stevewillard]

In his book Post Exposures, Ctein oils in film for enlargements as standard practice. He uses Edwal No Scratch which is a transparent oil that has the same index of refraction as film and eliminates dust and scratches. He claims it is much quicker to oil and clean the negative then it is to spot each print.

From my own experiences I am in complete agreement. I do very big enlargements and small dust spots not visible on smaller prints become very noticeable on big stuff. It only takes about two drops of oil to coat the film. I clean the film after with PEC-12.

It will work with both color and b&w negatives and also helps minimize Newton rings.

B&H sells Edwal No Scratch, but cannot ship it because it is classified as hazardous material. Calumet sells it and ships it for about $10 a bottle plus shipping.

 

[clayne]

Thing is, in opposition to spotting - which is easy to reproduce - how much will negatives put up with this before they start to degrade?

 

[flash26c]

I've used Edwal No Scratch and it works really well. I had never thought to use it on all my negatives -----

 

[rmolson]

wet mounting

Years ago I used a liquid carrier on an 8x10 durst condenser enlarger to make color separations The carrier required a frame for the slide to rest in,. otherwise it would float. We would hinge the slide with a piece of tape and then carefully drop by drop fill the frame space .with the fluid . We used regular baby oil or glycerin in a pinch then drop by drop a light film of oil was placed on top of the slide and the cover glass gently lowered on the carrier. It was a messy process but at the time hide all the scratches on the base side of the slides. When we got scanners we still oil mounted them on the drums for the same reason. We never used it to hide dirt. Just careful cleaning and neutralizing any static took care of that. I have never tried it with B&W all my enlargers are equipped with cold lights negating the need to hide base line scratches.

 

[richard ide]

I regularly mounted negatives with mineral spirits in horizontal enlargers using only one piece of glass. It was very fast to change negatives.

 

[Peter De Smidt]

Be careful with flammable liquids and hi-watt enlargers.

 

[edtbjon]

Has anyone tried wet mounting negatives in a glass carrier for enlarging? As far as I understand, in the *gasp* digital world wet mounting negatives is standard practice for the highest quality scanning. Among many benefits it virtually eliminates dust problems, eliminates newton rings, confirms flat registration of the negative, and leads to a sharper, truer contrast read of the negative probably by somehow reducing spurious and imperfect light reflection/refraction (I think this has something to do with the perfect surfaces created by the mounting fluid and the glass).

Also, I haven't confirmed yet, but I believe it may slightly change the working density of the negative by swelling the emulsion and thus spreading the grain. This is the same effect that we see in a glistening wet print (which later dries down to something different than what we expected ;-) ). I'm not sure if this is a proportional, linear, or subproportional density change, but it might prove to be a useful tool for the printer's toolbox.

Anyone tried this? Any thoughts/experiences?

I havn't tried wetmounting in an enlarger yet, but I'm seriously going to try it out. While not discussing the howto's etc. of scanner wetmounting, the idea is to get the "hang of it" in terms of avoiding bubbles etc. The very same do's and dont's will of course apply to enlarger wet mounting.
My main reasons for wet mounting for scanner are flatness which give overall sharpness and dust/scratch supression. I will try wetmounting for enlargers for the very same reasons. Part of my decision process is of course the fact that both my enlargers are condensor light enlargers (A Leitz Focomat IIc and a Durst 138S with a 139 bottom) where I like the quality and inherent sharpness of the light, but I know better things to do with my time than retouching. I've tried several cold-light enlargers, where size does matter. I.e. cold-light is OK for larger formats, but I simply don't like it for 35mm. And I don't have the money to just try some other cold-light solution which will work with the VC papers I usually work with, as most soft/cold light heads doesn't work well with VC papers.

I'm sorry to say that your second idea about comparing with a wet print doesn't hold, as the wet vs. dry print issue is all about reflection. A wet (i.e. very flat and shiny) print surface reflects more light than a dry print surface. This is something which cannot easily be compensated with e.g. more viewing light. This phenonema doesn't happen when you compare e.g. wet vs. dry negatives, as you don't look at the reflection of them, you look through them.
But I give it to you that you did at least try to find a solution.

//Björn

 

[Dr Croubie]

So, rather than start a new thread, I'll resurect something 10 years old.

I just got my first glass carrier, the universal 6x7 for my LPL6700. Did one RA4 print and yep, the first thing I noticed was the newton's rings on it. (I've never had them on anything before, probably because all my prints thus far were glassless 135, and all my scans were either edge-holders or wet-mounted).
I'm well used to wet-mounting my BetterScanning holder on my v750, with Aztec mylar and Lumina fluid (can't get Kami fluid in Australia, some mailmen have a thing against delivering Petrol via airmail or something...)

So, in the intervening years since this thread first came up (glad to see I'm not the only one who's thought of it), has anyone else tried it?
Specifically I'm wondering about whether to just fluid both glass-holders and hope for the best in when sandwiching, or remove the lower glass and wetmount to the top glass with mylar just as I do with my scanner?
Do you have to physically cut the negative out of the strip to stop airbubbles coming back in? (I presume so but hope not). When I scan, the mylar goes all the way around the neg strip on all 4 sides, but a neg carrier is only 7cm long, not 25 like my scanner.

Any other pitfalls to watch out for?
Lumina isn't explosive like Kami but I still presume I'll have to work fast enough before it evaporates, especially near an enlarger head (at least it's colour diffusion, I presume they're cooler than condenser?)
Any other tips or experiences?

 

[chip j]

Carlwen, I believe used to make a"wet" negative carrier. I was always interestedin it but didn't find out much about it, except that the "fluid"as on both sides of the neg.

 

[Ian Grant]

Wet mounting was first recommended for miniature formats negatives around 1927/8, you overcome some of the issues of grain and graininess caused by processing issue usually due tom temperature variations affecting the gelatin super-coat. With wet mounting the apparent graininess of the prints can be reduced,

It's acontentious ussue not believed by one old man but surfaced recently in a post about HP5 where Ilford found slight reticulation which matched exactly what I've always said about Micro0reticulation.

Ian

 

[Mustafa Umut Sarac]

I wet mounted least ten thousand slides including 8x10s to larger sizes to small diameter and large diameter quartz drums for to scan with Crossfield 656 drum scanner. I think this is forgotten art , no more slides and drum scanners for printing industry and most easy way is to use vaseline. I was using 1 liter cleaning solvent everyday and I dont know its brand. It is the most important part of wet mounting , it easily cleans the film and extemelly fast evoprates. And lots of cleaning tissue is required. Best way to stop bubbling , is to use a loupe and spreading out the bubbles with pressing and sliding your finger on film. If you want to stop newton rings and not use any wet chemical , anti newton ring spray is your friend. I dont think you would neeeded to clean it. But 20 years ago ..

 

[Paul Howell]

I have printed from wet negatives when really pushed to meet a deadline, used a glass carrier. I dont recall differance in the quaility of the print, I may give it try just see what happens.

 

[DREW WILEY]

It's messy. The old Carlwen carriers come up for sale relatively mauled from time to time. Any decent machine shop with CNC could make something much better new nowadays anyway. Scanning fluid. I prefer just to use Antinewton glass on both sides of the neg. Doesn't affect
sharpness at all if you do it right and use a diffuse light source. AN sprays are a messy headache too. Basically, aerosolized corn starch. You
spray it in a little cloud, then swipe the neg through the cloud. Don't spray it onto the neg directly. And do it under a fume hood, cause the
propellants are not healthy to breathe. Same outfits that supply scanning fluid can sell you this too, if you choose to use it.