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View Full Version : How to make a BW copy negative from 4x5 Velvia transparency



robert taylor
23-Oct-2012, 13:51
I have a 4x5 Velvia transparency (positive) I want to make a 4x5 black and white negative from so I can enlarge it to make a black and white print in the usual way in my darkroom. I need some guidance on this as I've never done it before, and will be "totally in the dark"--no pun intended of course--regarding what black and white films are best for this, how many steps are required, what techniques give the best result, etc. I have no idea, w/o blind random testing, what exposure times at what f stop would put me in the ballpark for this either. I am hoping one or more of you may actually have done this yourself and can guide me away from the pitfalls that otherwise await me. If you have done this and would be so kind as to help me with it, I will be greatly appreciative!

Robert

Charlie Strack
23-Oct-2012, 14:07
Enlarge it or contact print it directly onto B&W negative film. Using the enlarger can allow for some dodging, burning-in, and cropping.

Slow speed film is very useful, as it's very hard to accuractely time the short exposures. The exposure time is determined by trial and error. Since you only need to develop one sheet at a time, tray development is the easiest--your regular print developer can be used, though you might want to dilute it more than usual.

If accurate rendition of color to gray is important, use panchromatic film; if it is not critical, you can use orthochromatic film with a red safelight. Reds in the transparency will come out very dark. Ilford still makes Ortho Copy Plus (B&H shows it in stock).

Note that you can use your color filters in the enlarger (if you have a color head), to adjust color contrast--just like on-camera filters.

None of this is hard--I did it years ago, but it is all trial & error--there's no magic formula I know of, but it is very easy. Use a Kodak projection print scale, if you have one, to get close on exposure, but cut the time from 1 minute to 6 seconds. Then the time you need will be 1/10 of what is indicated.

Charlie Strack

Drew Wiley
23-Oct-2012, 14:08
If you have a decent little contact printing frame you can contact the original and copy
neg together emulsion-to-emulsion. You can exposure with your enlarger colorhead and use
contrast filtration just like in outdoor scenes (just realize you are using a warmer light source in the enlarger itself). Films like FP4 and TMY do a nice job. You will need to experiment a little to determine correct exposure time and amount of development, but in
principle, this is easy. You might need some antinewton frame glass, or you can use frosted mylar between the glass and the shiny base side of the film to prevent rings.

Kirk Gittings
23-Oct-2012, 14:14
What kind of quality are you looking for? I have utilized internegs my whole career for a variety of purposes and I think the best are created these days by scanning, coverting to B&W (with tremendous control of tones) and then output to 4x5 b&w film through a film recorder.

vinny
23-Oct-2012, 14:51
are you open to the idea of using ilford direct positive paper and just printing it that way?
I've make b+w prints from slides with the efke stuff.

Drew Wiley
23-Oct-2012, 16:21
Ah Kirk, the "best" are done without all that intermediate quality loss. Internegs got a bad
name by clock-in/clock-out sloppy labs or automatic duping gear. There's nothing like an actual contact. But I won't complicate the tonality aspect other than to query just how long film recorders themselves will be servicable - and they seem to have format size limitations. Check with Jim Browning on that subject - there is a reason why he built his own 8x10 version rather than using something off the shelf. One more complicated gadget
dependent upon electronics and software. Life is so much simpler when we're kept in the
dark!

Drew Wiley
23-Oct-2012, 16:27
Robert - if you can latch onto what's called a masking registration frame and punch you
save a lot of headaches. Once in awhile a used Condit set comes up for sale. Otherwise
there are a couple of outfits who still make sets for up to 4x5 film - perhaps Inglis and
Radeka - check for ads on APUG or do a web search. You punch the film for registration
pins on the contact glass, so that they precisely overlap. Otherwise, you can just guess
using a larger piece of black and white film like 8x10 TMY,TMX, or FP4 - all of these have
a nice long scale suitable for interneg work. Then the same gear can later be used for
advanced curve control if you wish, like "unsharp masking" (which is probably the terminology you're most likely to find gear advertised under). Don't be intimidated. It's fun
if you gravitate toward darkroom projects.

Kirk Gittings
23-Oct-2012, 18:05
That's exactly what I am talking about. I had it done that way for 30 years. then in about 2004 a guy offered to do a scan/film recorder for me. I had them done by some of the best in the country, hand done, expensive and I did many myself-can't come close IME to a high quality drum scan, adjusted in PS and out put through a film recorder-no dust near total control of tonal relationships.

ic-racer
23-Oct-2012, 20:20
You will get the best results with the equipment you already have in your darkroom. When I do this I projection print it onto some continuous tone panchromatic film with the enlarger. I like to go one size up if possible (5x7 or 8x10) to give a nice big negative to work with. I process the films in a Jobo daylight tank that holds a single sheet of film.

sanking
23-Oct-2012, 20:38
I made enlarged negatives with analog methods (from B&W and color negatives, and from color transparencies) for more than two decades for printing with various alternative processes. Some 8-10 years ago I switched to scanning and printing digital negatives. For me the consistency, and the "near total control of tonal relationships" that Kirk mentioned, easily makes the digital work flow "best". Not even a close call IMO.

Sandy

BetterSense
24-Oct-2012, 07:33
I've done this both with the enlarger and contacting. Quality is excellent either way. It's one of the only reasons for me to shoot positive film for color, since I have to print color digitally anyway.

I prefer to use TMX. I use some scrap film or paper on top of the negative carrier to attenuate the enlarger light to get ~10s exposures while using a reasonable enlarger aperture. You can put a grey card on the easel and shoot it with a spot meter, using F/1 as an aperture. This will get you in the exposure ballpark.

It's just as easy to make a 4x5 interneg from 35mm or medium format slides. Medium format chrome film is cheaper and doesn't have as many dust problems as 4x5.

I've also used this to rescue under-exposed color transparencies. You can knock out a quite nice B&W interneg from a chrome that is very under-exposed. I suppose the same negs might be salvaged digitally as well, but I'm not sure about scanner DR on such dark transparancies.

Maybe people that already have super-good scanners and don't mind spending the time scanning and doing the digital thing might think that's easier, but to making an interneg is easier. In order to scan film well enough that it will truly beat out a contact-printed interneg in resolution, means you have to use a very good (drum) scanner. If you have that technology sitting around, great.

robert taylor
24-Oct-2012, 11:52
After all these years in the darkroom, it sounds like I owe myself the experience of doing this film-to-film, to pay my dues, so to speak. If that proves successful some of you will also have peeked my curiosity enough to try the digital route as well, as a point of comparison, as well as what for me would be an out of the box experience. Colorfolio (not far from where I live in Mendocino County)-Drew may know of it-does high quality drum scans and whatever else digital one may require. I am lost on the "film recorder" reference, however--don't know what that is.

From what you've so generously taught me collectively, it sounds like I could start by using my Radeka pin registration carrier (with anti Newton glass) as a contact printer, cut some 4x5 Tmax or TriX film into 3 pieces to use as test strips sandwiched individually under the Velvia, make a 10 second exposure at f 11 with the enlarger cranked way up for starters (with the option to attenuate the light further with a sheet of Duralar in the negative carrier), and then test develop to obtain a properly exposed negative. PLEASE reject, revise or otherwise tweak this basic plan for me if you find it flawed (my wife thinks I've become more generally flawed with the passage of time anyway, so I assure you your revisions, kind and impatient alike, will only be welcomed). As to a properly developed negative, do you agree with the suggestion to use a print developer (Dektol is my usual) or should I go with a film developer like Tmax Rs 1:4 or HC110 dilution B?

Finally, I thank you all very very much for taking the time to help me with this. It is wonderful, especially remembering how isolated we were in the pre-internet years, to have such a sage and sharing team as you are only a few clicks away. As a side note, only about 5 years ago, I "discovered" Sandy's pyrocat hd, and for that alone, I am forever grateful to him. Thanks again to all!

Robert

Kirk Gittings
24-Oct-2012, 12:17
my wife thinks I've become more generally flawed with the passage of time anyway

You are not alone in that brother......:)

Drew Wiley
24-Oct-2012, 12:53
Guess it's just what you like to do. There's tons of info out there on negs via scanning.
In the good ole days Kodak make a special copy film for just such a purpose, where you
could alter contrast by where you placed the exposure on the substantial curve variation.
I like straight-line films better. Eliot Porter would simply take red separation Super-XX negs
for his DT work and print them b&w, presumably because the scale was better than B&G
separations (which required tweaking in the next step). You want the final neg to be a
tad soft (because the chrome will itself probably be contrasty), and to have full shadow
value (generally won't be much there anyway). With modern VC papers you can just split
print and control the extremes, maybe easier than in PS (but my carpal-tunneled fingers
are already prejudiced against keyboards and mice - don't understand why my cats like
mice!)

LF_rookie_to_be
25-Oct-2012, 07:51
Emulsion-emulsion contact copying works wonderfully. If done properly, there's very little detail loss, probably mostly in the deepest shadows. Below are two 1:1 details of a drum scan of a 4x5" Velvia 50 contact internegative on Kodak 100T. Though not color-to-B&W, they may give you an idea of the level of detail possible. Scanner was carefully focused and negative scanned at 16-bits linear. No profile embedded either during scanning or PS cropping.

82533 82534

Drew Wiley
25-Oct-2012, 10:37
Per developer - I like HC110 for duplication work because it keeps quite well and is reliable
over a wide range of dilutions. But you can use ordinary film developers like #76 just fine
too for an application this simple.

BetterSense
25-Oct-2012, 20:24
I use film developer. Usually HC110 because it's easy, or whatever I have around that is getting long-dated.

robert taylor
25-Oct-2012, 21:56
I'll have a go with my HC 110, then. I have some Ilford Ortho copy film on the way from B&H. Thanks to all again for your guidance, and thanks too for the
attached detail images above.

Robert