A few questions/comments about RA-4
I appreciate that there have been numerous posts recently about RA-4 printing and apologize if this one seems to be an exercise in beating a dead horse. Your comments/suggestions would be very helpful. Thanks in advance.
I have just finished my first box of 8x10 Fuji Crystal Archive type C glossy paper and am not completely satisfied with the results. I was hoping to get as close as possible to the print equivalent of Velvia 100 film. I process in trays at room temperature using Kodak chemicals and a Saunders dichroic enlarger and the negatives were shot with a Hasselblad. I have no trouble with the process -- the outcome is always very reproducible and very robust against things like developing time and age of the chemicals (I got about 50 prints over 6 months with the last chemical batch and couldn't detect much change in the results).
First, is there any way to reduce the contrast in the print? Searching the archives, I didn't see any easy way to do this and the usual approach in BW printing of reducing the development time doesn't work (as I confirmed). The contrast with Ektar negatives is very high (less so with Fuji 160s negatives).
Second, I photographed a USAF resolution test chart (Ektar 100) and printed it. The resolution of the print was much, much lower than that of the negative. I am very careful in using a grain focuser and tested for errors in the enlarger focus by bracketing the focus and found none. I had heard (from the Ctein book "Post Exposure") that RA-4 paper should have 60+ lpm resolution and my results are very far from this (no better than about 20 lpm or less). The prints have a slightly unfocused appearance. I am using an El Nikor 4 element 80 mm lens.
Finally, has anyone experienced problems from breathing the chemical fumes? I have an exhaust fan (the darkroom is a converted bathroom and has no windows) and also wear a mask (a cheap one from home Depot) with which I usually can't detect any chemical smell (it is strong with the mask off). The mask might be losing its protection recently -- two days ago, I did detect chemical smells and was coughing after the ~2 hour darkroom session.
Good RA4 colour printing is about getting control of all the variables that impact upon what is primarily a process designed for machine processing. I can tell you with certainty because I have done the experiments that you will never get optimum results using Kodak RA4 chemistry at room temperature. The only other brand I have ever used was Agfa when it was still available and the results were pretty much the same so I expect changing chemistry would not help.
You can process the stuff in trays but you need to use a water bath or some other means to get that temp up to 37F/100F if possible or close to it and be able to achieve that same temp every time you process. I know that leads to very short processing times but that's one of the variables that needs to be managed. If I understand correctly you are reusing your chemicals in trays over a 6 month period. If so I'm surprised they remain viable for that time and IMO could not possibly give constant results from batch to batch.
Unsure where you are coming from in trying to match a Velvia 100 print since Velvia is a tranny film and prints from it would have to be made either from an interneg or digitally or on Ilfochrome - none of which produce a result comparable to a RA4 print from a properly exposed and processed colour neg.
I've not found that RA4 materials produce excessively contrasy prints unless the negative itself is very contrasty and that too is an uncommon situation because of the exposure latitude of most colour neg films. Are you processing your own negs? If yes, there could be a problem there. When trying to refine a colour printing setup it is wise to use correctly exposed test negs that have been professionally processed - again it is about controlling the variables.
I have never seen an example of a fuzzy image caused by a lack of resolution in the printing paper. Because colour paper is multi-layer I suppose it is arguable that it must lack resolution compared to say a single layer B&W paper but I've never noticed it. The lens you are using is not the best enlarging lens ever made but it's still pretty good and would be more than up to the task of printing say a 16x20 from a 6x6 neg. Sounds like a focus or paper flatness issue.
I've not experienced health problems with the fumes from RA4 chemicals but for what it's worth I once replaced an air conditioner in the darkroom and found that the copper tubes within were oxidized black and partially corroded, presumably from the chemicals in the atmosphere which would have been predominately RA4. OzJohn
Thanks for the response, OzJohn.
I was a little unclear about what I meant by the E6/C41 equivalence. What I mean is making the characteristics (color, contrast, resolution) of the print similar to those of an E6 transparency. I appreciate that one is a reflective medium and one is transmissive, but I wanted the print to look similar to the Velvia on a light table. To that end, I have been loading two backs with E6 and C41 film and making identical exposures with each (using Ektar and Velvia, even the speed is the same). I take mostly static subjects always using a tripod.
Using Ektar (store processed), the density range of the negative is definitely greater than that which can be handled by the print medium (Fuji CA). I can increase the aperture of the enlarger lens and get the highlights in range but not the shadows and reduce the aperture and obtain the reverse situation, but never both at the same time with Ektar.
I am not too bothered by the consistency or color of the prints. In fact, I am amazed by the robustness of the RA-4 process -- I have changed various processing times by factors of two with almost no visible change in the result. The changes in the print appearance were almost undetectable when I dumped my six month old chemicals and used fresh stuff.
After a few trials (and with the help of the Kodak viewing filter kit), I can get reasonably accurate color. I therefore don't think that the temperature is the problem, unless it affects the contrast also. By the way, numerous posters on APUG seem to have a similar experience as I have, reporting that the chemicals can be successfully used at room temperature for many more prints per liter of solution than Kodak recommends.
I do have a water bath with a very precise temperature controller for my E6 work, but it would be difficult to use for tray processing. (I have ordered some drums, mainly to reduce my exposure to the fumes -- I might try processing in the drum at 38C when I get them). I also find that my E6 processing seems to not be bothered by using older concentrates -- I just processed my fifth roll of E6 using chemicals (Kodak) which were first opened almost a year ago and the results were perfect, so far as I can tell and I examined the slides under a microscope).
Kodak Endura paper has a history of good results when processed from 68 F to 100 F with compensation in time and color balance. Fuji CA has had a checkered response under these same conditions. However, even with the Kodak paper, you must use RA-RT developer Replenisher with no starter!
I may be insensitive, but I notice no severe odor to any of the chemistry except a mild aromatic odor to the developer due to the DEHAO used in it and the blix due to the ammonia. Other than the color developing agent, the developer is remarkably similar to Dektol with a few added ingredients such as an optical brightener.
You can lower contrast by the use of Sodium SUlfite at 0.5 - 1.0 g/L when using Kodak paper. IDK about Fuji paper.
Thanks, PE. I will try the Sodium Sulfite addition.
Upon your suggestion, I have been mixing the RA-4 developer without starter.
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By the way, I assume that the Kodak Supra Endura paper is only available in rolls, not in cut sheets. I did see a roll of 600+ feet (8 inch wide) selling for ~$270, which is an amazing price, but one needs to cut it in total darkness. One advantage is obtaining 8"x8" squares without wasting paper (I prefer the square format).
I cut roll paper with a cheapish Dahle cutter.
I have a roll of 610'x10" Kodak Edge that was laughably cheap.
I avoid a safelight when cutting but use one when I'm printing in trays.
$270 for a roll? I've been buying even older paper, Kodak Ektacolor Supra III in 575' rolls for under $30! I'm crazy I know but I just cut it in the dark with scissors... should really work out something better (I waste a little paper but I have 575' feet so I'm not too worried). Still looks and works great, in fact the 2009 expired cut Supra Endura needs more yellow filtration to avoid being too warm so the older (can't remember how expired, years and years) Supra III lasts very well.
I process both the Kodak Supra III and Supra Endra and Fuji CA Type II at room temperature (22-24C these days, 18-19C in winter) in the Kodak Ektacolor RA RT replenisher (no starter) 10L kit and the matching 10L blix kit. I use a citric acid stop bath. I work under a Kodak #13 safe light with 15 watt bulb bounced off the ceiling, very little light but enough to see what I'm doing (by contrast I can easily read data sheets under the Ilford 902 for B&W work).
The Fuji CA Type II is higher contrast for sure but being newer requires normal color correction unlike the expired paper which needs extra yellow. I generally like contrasty prints so I don't mind it really, even with Ektar.
By overexposing Ektar (shoot at 50) you can get very dense negatives. The highlights will block but I find this compresses the contrast some. I develop my own C-41 so I can control the development there though I use my 1L JOBO Press Kits to 200% of capacity (24 rolls/litre) so I guess I'm not super picky.
Are you just making straight prints? To get the right highlights and shadows I find I need to dodge and burn, just like B&W. By stopping the enlarger lens down I can get 35s exposure times even for 5x7" prints which is enough time for me to dodge and burn.
Odors? B&W fixer is sharper and much more noticable. Low odor stop bath is fine.
The Ektacolor data sheet says it makes 16 8x10" prints per litre, or if you don't care about quality then up to 40 prints per litre. I'm getting about double that, 80 8x10" equivalent prints per litre. The Kodak data sheet also says not to use it in an open tray for more than 4 hours but I certainly use it for longer than that as I'm slow sometimes unless I'm making 50 prints of the same negative in which case I can use a print safe and process a group. I'll often have it in the trays all day and I'll use it another day or two if necessary. The developer turns into a disgusting brown soup when its really dead. The blix seems to last longer than the developer but I dispose of both at the same time.
On the topic of non-Fuji paper, does anyone know which Kodak RA-4 papers are currently being manufactured? I have noticed that a number of places still sell Ektacolor Edge and Ektacolor Endura papers both in sheet and in roll form. Also, I assume that one should avoid the Endura papers with a VC designation. Finally, although my Fuji paper is simply "type C", I have heard about "type C, type II" paper being sold. Is this very different from what is simply type C?
Finally, does anyone have experience with the "fine focus control" for LPL enlargers? KHB is selling them for about $100 and I am wondering whether this would be a good investment for someone who is interested in very high print sharpness?
Thanks very much -- this forum has been extremely helpful.
I've got that fine control for the LPL and I find it a really big help. Rather than getting it at KHB for $100, I found a fine focus wheel on ebay from a Philips enlarger which fitted perfectly and saved me a lot of money.