Contact printing frames for ULF

I am preparing for contact printing of 12X20 camera negatives. I

understand that probably the finest means is with a vacuum easel. Is

it necessary for me to look towards a vacuum easel for this format?

I use a conventional printing frame for my 8X10. Will a frame of that

type work for 12X20? Will it give me good enough contact? Thanks for

all responses.

I have been using 2 sheets of 1/4 inch plate glass for my 8x20 negatives, one on top

and one on bottom. Works well for me with Agfa MCC Fiber paper. Set me back

about $17.

There are vacuum easels and vacuum frames. I believe that you would want a vacuum frame. I have a 17 x 22 I bought used for about $175 that I use for platinum printing. The vacuum frame has a hinged glass cover over a flexible rubber bed. An electric vacuum pump pulls a vacuum of about 25 inches of Mercury. That much even pressure gives superb contact between negative and paper.

 

I would advise using this for the ULF negatives to get solid contact between negative and paper. It will avoid blurs and weak highlights with the big film.

 

Check used printing equipment houses for this type of equipment.

I use both a vacuum frame and a contacting printing frame for 12X20 negatives. You can get acceptable results with a printing frame if you exercise care in maintaining even contact across the entire area of the film but this can be very difficult with negatives as large as 12X20, and even in the best of cases your results may be inconsistent. However, there is no question but that the vacuum frame is superior, and I can visually see a difference with comparison prints made both ways. Prints made with the vacuum frame simply have a snap to them that those made with the printing frame lack. The difference ranges from very slight to considerable but the advantage always goes to the vaccum frame.

 

Sandy King

Yup. What you want is a vacuum frame, not a vacuum easel. And

there are used ones at Graphic Arts supply houses that sell

used equipment. Working with one is quicker than working with

a contact printing frame or with anything else. Other things will

work, but, heck, if you can afford it go with the right thing the first

time.

 

Michael A. Smith

Our NuArc will hold up to a 35x45" item; and has two different light sources way above it; which move on a track. This is to position the lamp directly over the item; which maybe an odd size. The vacuum frame is also used to spraymount foam core; with a giant spraybooth nearby. For small 12x18" negatives that are contact printed; sometimes a large piece of glass is used; thick enough to make the negative and paper always in contact. A dual usage vacuum frame gets crud from inkjet; paper; foam core; and dust; and must be cleaned on a regular basis. A small piece of glass maybe kept in a giant envelope; and used only when needed. The vacuum frame must be clean; the work inserted; and the glass hinged down and clamped; then the unit takes many seconds to pump down; then the exposure is made.

Greetings,

 

While I only do 11x14 at the moment, the vacuum frame is the way to go. You might be able to find one cheaply, by searching the printing (not photography) categories on eBay. NuArc, as well as others made these devices. The one I use is built in to the NuArc UV exposure unit and it only takes a few seconds (5 or so) to pump down.

 

Regards, Pete

I will agree with the other respondant that I prefer a vacuum frame for 12X20,

and have experienced poor contact with contact printing frames in this size.

Another point worth mentioning: one of the big advantages of 12X20 and

other ULF negs is the ability to do alt process. If you do Pt or other alt

process, a plate burning unit like a NuArc (which is what I use as well) allows

you to see you neg (as opposed to the cheaper "pizza oven" design with

fluorescent tubes where the neg goes in with a contact printing frame and is

not visible). A plate burner (light source above, vacuum frame below

integrated into a single unit) thus allows dodging and burning. Though all

agree that Pt/Pd is much more forgiving of contrasty negs than silver, I don't

know many serious Pt/Pd printers who don't eventually want to do some

dodging and burning. You can do that with a plate burner but not a "pizza

oven" design. That's a critical advantage to me, though it may apply to fewer

than 25% of he negs I print.

 

Good luck,

Nathan