Kentmere VC Select RC Paper

[Ryuji]

As most people who read my posts already know, I love AGFA MCP semi-matte and bought quite a bit of it before AGFA was gone. However, the problem is that I can no longer recommend other photographers this paper due to lack of supply. I was looking for a good RC paper that I can recommend.

My criteria are:

* must have good tonality with strong black
* the paper base must be bright white
* the developed image must accept toners very well

As you see in the title line, Kentmere VC Select in Fine Lusture surface was very good, and met all these criteria. I tested all paper samples in Silvergrain Tektol Standard developer diluted 1+9 (or DS-14 if you want to make it yourself).

The differences were:

* AGFA MCP makes image hue on the slightly warmer side of neutral
* VC Select makes neutral black
* AGFA MCP has significantly thicker paper base
* VC Select is slower to develop

For the toning test, I did the following:

1. develop the paper in Tektol Standard 1+9 until the development is complete. For MCP, it takes about 60-90 sec to complete, so I gave 90-120 sec dev time to be safe. For VC Select, development was a bit slower so I gave 2 minutes development. (When comparing for toning, it is very important to develop each paper to completion.)

2. stop in acetic acid stop bath

3. fix in Clearfix 1+4 for 1 min

4. rinse in water, and hold prints in water bath

5. tone in my polysulfide + selenium toner (similar to discontinuted Kodak poly toner)

6. wash aid, wash and dry as usual

Despite the difference in the image tone after development, both papers produced beautiful brown black after the toning stage. To the toner bath, I added one test print each 30 seconds and the samples were processed together until the first test print was considerably more brown than my taste. All samples were taken to washing aid to halt toning and washed for comparison. Both papers produced similar range of colors depending on the toning time, although with the Kentmere, visible hue shift was a bit slower to kick in than AGFA.

Since I tone all final prints, I find Kentmere VC Select to be an acceptable substitute for AGFA MCP.

Many other papers that produce neutral black image tend not to respond well to toners, or the process can take excessively long time. For example, many Oriental papers, Kodak Kodabrome papers, etc. do not produce beautiful brown black tone even when toned in my aggressive toner. AGFA MCP and Kentmere VC Select are exceptions in this regard.

Not yet done:

I haven't compared sensitometric curves.
I haven't run accelerated test of the images on Kentmere yet.
I haven't used other dilutions of the toner yet.
I haven't used bleach on Kentmere yet.

When I get more details, they will be posted on silvergrain.org website.

[pentaxuser]

Many thanks for this kind of sharing. It's members like you and posts like these that make my subscription to APUG so worthwhile. On one's own it would be near impossible to get this kind of info these days.

Looking forward to your other tests as mentioned in your post to be done in the future.

pentaxuser

[Bruce Osgood]

Thank you for your testing and shared results. Kentmere has been my replacement paper to Forte. I am surprised with your selection of the RC paper in place of the VC that I thought was the 'standard bearer' of fine print photography.

[Ryuji]

I do use FB and have no problem with them, but for the types of images I produce, RC works better due to brighter base. Seriously, many images I make look far better on RC than FB. The key is to select the surface texture carefully, and process and tone the RC prints with equal attention that you would give to FB prints. Another reason I don't post much about FB is that there are good info about them already but there is not much useful info for serious users of RC paper.

People are concerned about the longevity of RC, but with papers I tested (they are all made by AGFA or ILFORD after c. 1995) I haven't seen any problem that cannot be prevented by polysulfide toning, and indeed this is what I do anyway, so I am not concerned. Indeed, color papers on market today are also RC and they are also heavily tested by manufacturers and third party labs, and they conclude the limiting factor is the lifetime of the dye and not support. With b&w images the standard accelerated testing condition is high concentration of peroxide fume in high humidity as the silver image is the weakest point and this weakness is most accurately measured by peroxide fuming. Silver sulfide is very stable and extremely resistant against peroxide and other oxidative attacks. On the other hand, the color materials are tested with a host of compounds as well as lighting conditions because the color dyes can be degraded by several ways. Many of these testing conditons are also harsh to the paper base as well. It's worthwhile noticing that those tests of color RC papers didn't find problems that are fatal to the support. Silver sulfide is more stable than color dyes used in those papers, and the support is very durable. The choice between FB and RC should be made primarily based on the aesthetics not outdated opinions of poorer RC permanence.

[john_s]

.............
5. tone in my polysulfide + selenium toner (similar to discontinuted Kodak poly toner)
...............

Ryuji, is your polysulfide + selenium toner the formula given in the Kodak pdf link on your website? If so, do you start with a standard potassium polysulfide + sodium carbonate toner (more or less what Kodak Brown Toner was) and follow the Kodak instructions in CIS268.pdf?

[Dave Krueger]

5. tone in my polysulfide + selenium toner (similar to discontinuted Kodak poly toner)

Ryuji,

Where can I find out more about this toning scheme?

-Dave

[Uncle Bill]

Very interesting reading, I print both FB and RC, both have their pluses and minuses like any medium. To date my RC paper of choice is Ilford Multigrade IV Glossy and FB has mostly been hand me downs. I think the longevity issue is academic now. I use Sistan to treat my RC prints at the end of the process. I would like to know about other toning processes as well in case my supply of Sistan runs dry.

[Ryuji]

Ryuji, is your polysulfide + selenium toner the formula given in the Kodak pdf link on your website? If so, do you start with a standard potassium polysulfide + sodium carbonate toner (more or less what Kodak Brown Toner was) and follow the Kodak instructions in CIS268.pdf?

Oops, I missed your posting.

I started making my combination toner (a class of toner containing both polysulfide and selenium) BEFORE Kodak published CIS268, and the formulae differ. Also mine has an additive that reduces the odor (but it does not eliminate it) and the risk of stain with some paper (such as AGFA MCC). This additive is not offered by common photographic chemical suppliers (that is, there's no easy way to buy it). The compound itself is not that esoteric but none of the chemical engineers I work with seem to be able to find a source that's smaller than 220lbs (or something like that) drum. So in interest of saving myself some trouble, I'm not ready to described it much at this point.

You can make the toner described in CIS268 from raw ingredients. What you need to know is described in the obvious website:

http://wiki.silvergrain.org/wiki/ind...tle=Poly-Toner

With the other interesting thread in mind, I would say that the toner is the most rewarding area to make yourself because most of the good products are gone or never offered before. However, making toner from scratch is always associated with safety risk. Selenium dust, H2S gas, caustic ingredients, etc., and ALL of the strict darkroom safety precautions and more are in order. I've also got a few inquiries as to whether I'm willing to license my toners so that someone can make them, but the problem is that few chemical plants today are equipped with necessary safety features and contamination-free setup. (The concern is the manufacturing of the toner can contaminate other things they make in the same plant!)

[psvensson]

Thanks for the detailed test! I too loved Agfa MCP for its beautiful look in warmtone developer, so I'll probably be giving Kentmere a try.

[Matt5791]

Kentmere VC Select is my standard general purpose RC paper - I favour the snappy look I find easy to achieve with this paper.

Ilford MG IV is my favoured general purpose FB paper.

Matt