Kentmere 100 & 400 in 120 format

[Andrew O'Neill]

Although I'd rather see Delta 400 in sheets again. They have the conventional films covered with HP5, but Ilford doesn't have a tabular film in 400. I'd rather buy a 400 sheet film at the Delta price point than TMY.

Well, if Ilford introduced D400 in sheet sizes, I would be very happy...but, I believe Simon Galley years ago, explained that if they did that, it could impact on sales of HP5. I guess the same could happen with if sheet sizes of Kentmere were brought to market.

 

[Dusty Negative]

I have gone back to my files and dug up an Ultrafine Extreme 100 negative in 120 size. I checked the B+F density, and it is 0.28 (developed in D--76), so it looks like it is a very similar base to that of the Kentmere 100. I suppose there was some consensus at the time that Ultrafine Extreme was Kentmere, or at least similar to it.

When did Ultrafine Extreme completely cease distribution again?

Inquiring minds want to know!

 

[MattKing]

....maybe.....i still don't get the obscure connection to foxholes.....

It is where one might shelter when the fireworks (Photrio argument about Kodak) commence.

 

[GregY]

It is where one might shelter when the fireworks (Photrio argument about Kodak) commence.

It wouldn't be an argument.....just a back & forth between Sirius G & Drew W..... both south of the border.....
& just to start it off, if i had to choose one film across all the formats i use, I'd choose FP4+ over Tmax100......(allowing for the fact i really like TMX for certain things)........ & Plus X and Verichrome Pan no longer exist so they don't enter the equation. ......nor does cost IMO.

 

[aparat]

I have a couple of curves that simulate capturing the "normal" subject luminance range of about 7.3 stops (or LSLR = 2.2) for people who are interested in photographing such scenes. These are hypothetical curves based on the curve families for Kentmere 100 and Kentmere 400, respectively. The parameters of interest are listed in the left upper corner of each plot. Flare-corrected CI is listed as "Aim CI."

 

[GregY]

I have a couple of curves that simulate capturing the "normal" subject luminance range of about 7.3 stops (or LSLR = 2.2) for people who are interested in photographing such scenes. These are hypothetical curves based on the curve families for Kentmere 100 and Kentmere 400, respectively. The parameters of interest are listed in the left upper corner of each plot. Flare-corrected CI is listed as "Aim CI."

View attachment 324277 View attachment 324278

Aparat....for those of us who can read negatives & print...you know...practical application...but don't do graphs.... can you offer an interpretive meaning in a few sentences.

 

[aparat]

Aparat....for those of us who can read negatives & print...you know...practical application...but don't do graphs.... can you offer an interpretive meaning in a few sentences.

My usual disclaimer is that those are the results that I found using my testing conditions. The results are meant to be only starting points for further personal testing of the materials.

These "normal" curves are meant to represent a "normal" scene where the difference between shadows and highlights that one wants to capture is about seven stops. In such a situation, I would look up the Effective Film Speed (EFS, similar to Exposure Index) value (for Kentmere 100 it is around ISO 80, for 400 it is ISO 320), use an incident meter or measure off a grey card (or whichever surface one wants to measure off), and take a picture. Then, I would develop for 4:75 minutes (K 100) and 7:30 min (K 400) in D-76 stock at 20C in a rotary processor. That would result in a negative that should be fairly easy to print using a diffusion enlarger. If I was using a flare-prone lens, I would probably increase development time a little to compensate for the loss of shadow contrast. Here are two plots that summarize the relationship between Contrast Index (CI) and developing time for each film. I find that these plots are very useful and do not require any further abstraction (like the Zone System) to to interpret.

 

[wahiba]

What purpose will these new films serve if there are no medium-format cameras being currently produced? My Mamiya is getting very old and to replace it I see no alternative but another very old Mamiya...

I pensioned off my Rolliecord II a few years back. I reckon it was over 70 years old by then. I reckon it was half that age when I bought it so had a useful life of well over 30 years.

Diana with a glass lens is a good deal (better than the Belair).

 

[GregY]

miha said:
What purpose will these new films serve if there are no medium-format cameras being currently produced? My Mamiya is getting very old and to replace it I see no alternative but another very old Mamiya...

The whole 'camera store' gig is a business. They've got you convinced that you need to buy new cameras. I could recite a list of existing medium format cameras as long as my arm. Most of them work, or will with some periodic service (you know like an oil & filter change on your car). Plenty of cameras that take 120 film ready to produce the goods.

 

[removedacct1]

My usual disclaimer is that those are the results that I found using my testing conditions. The results are meant to be only starting points for further personal testing of the materials.

These "normal" curves are meant to represent a "normal" scene where the difference between shadows and highlights that one wants to capture is about seven stops. In such a situation, I would look up the Effective Film Speed (EFS, similar to Exposure Index) value (for Kentmere 100 it is around ISO 80, for 400 it is ISO 320), use an incident meter or measure off a grey card (or whichever surface one wants to measure off), and take a picture. Then, I would develop for 4:75 minutes (K 100) and 7:30 min (K 400) in D-76 stock at 20C in a rotary processor. That would result in a negative that should be fairly easy to print using a diffusion enlarger. If I was using a flare-prone lens, I would probably increase development time a little to compensate for the loss of shadow contrast. Here are two plots that summarize the relationship between Contrast Index (CI) and developing time for each film. I find that these plots are very useful and do not require any further abstraction (like the Zone System) to to interpret.

I printed one of my Kentmere 100 negatives the other day, and it printed surprisingly easily on a grade 2 paper. (Beseler 23C II with a condenser head)

 

[Craig]

Aparat....for those of us who can read negatives & print...you know...practical application...but don't do graphs.... can you offer an interpretive meaning in a few sentences.

As a simple summary, the curves he presents where there are multiple developing times show the exposure ( amount of light) the film received on the bottom and the corresponding density built on the negative on the vertical axis. A straight line means that there is a direct correlation between exposure given and resulting density of the film. Suppose you increase the exposure from one point to another by a stop, in the straight line portion the resultant change in the negative will also be one stop (if it is a 1:1 relationship - the important thing is it's a constant relationship). If the curve is more of an S curve, then there isn't that direct relationship anymore, so a stop more exposure might only increase the negative density by 1/2 a stop - you'd have to know exactly where on the curve you are to know the relationship. Depending on where you are on the curve, it can result in highlight tones being compressed together for example, or poor separation in the shadow tones. So if you see a long straight line portion of the graphs, it should be an easy film to work with for most circumstances. It will be a predictable film.

The slope of the line in the straight portion represents the contrast index. For a normal scene, you are looking for a contrast index of about 0.58 to be able to capture both highlights and shadow detail and be able to print them on a normal grade 2 paper. From the family of the curves, you can then determine a "normal" developing time to give a 0.58 contrast level. In this way you can determine a custom developing time for any film and developer combination, developed the way you develop film - either in a jobo, small tank, trays when doing sheet film etc.

If you shooting a low contrast scene - overcast, fog etc, then you can determine what contrast level you need to bring your image highlights and shadows onto a printable range and choose a developing time and film speed to suit your scene. Effectively, you will likely be pushing the film - underexposing and overdeveloping, in order to steepen the line, which means to raise the contrast level. That will separate the small range of tones in a foggy scene and expand them to suit the paper.

In a "normal" scene, you take a light reading and expose the film, that exposure point should fall in the middle of the curve. The shadows will be near the bottom, but hopefully still on the straight line portion, and the highlights will be near the top, but also on the straight line portion. Then you have captured the full range of tones availble to be captured in your original scene, and it will be a printable negative. If you overexpose, you shift to the top and some highlight tones may fall beyond the range the film capture, so those are lost. If you underexpose, the shadows will be down in the toe ( or below it) and the film will not receive enough exposure to capture any information and you lose shadow detail.

If you are consistently getting negatives that are flat for example, then you can do these tests to find the optimum developing time. From these tests you can also determine the effective speed of the film. The way the slope of the curve in the bottom of the curve ( the toe) changes can be used to determine film speed. There is a lot of literature on determining film speed, it's a complicated subject. So by exposing and developing 5 test sheets of film you can determine both your developing time and film speed for your processing style and conditions.

More than a few sentences, but I hope that helps your understanding a bit of the charts that are being presented. There is a lot of information you can extract about how the film will behave if you can read the charts.

 

[GregY]

Craig, Thanks for the interpretation..... pretty much what i've always done without reading charts. I've always preferred the practical approach. Expose, develop, print..... tweak when/where necessary. That's why in the long run I've used the same few films and the same developer.
That doesn't mean that i didn't read Ansel's The Camera, The Negative, The Print.....or other tomes.....
Personally I get the picture from the photo in Paul's post in #106.....& later where he said his negatives printed well on grade 2.

 

[Craig]

For me I was always getting flat negatives with HP5 when following the recommended developing times. So I decided to apply a bit of science and did the tests to generate those curves that Aparat did. I found that for HP5 in Xtol -R I needed to use the 1 stop push times to obtain a normal contrast. I went from a developing time of 7:30 to 9:30

All of a sudden I have much nicer negatives that print much easier, but more importantly for me I was able to do it with not much film ( 5 sheets of 4x5), but I also know why my negatives were flat, rather than guessing and hoping I stumble on something better. I was under developing, rather than underexposing. I'm not a fan of trial and error and hoping I can come across something that works, rather than doing focused testing that will lead to predictable results.

If a film or developer is discontinued, or I want to try a new film/developer combination I also know I can find the new developing times and film speed with relatively little effort. I'll also have a good idea of how the film will behave when I use it and what it will be good for, and perhaps more importantly what scenes it won't be suitable for.

 

[GregY]

Craig I'm glad that worked for you. I'm in the "a picture (or negative) is worth a thousand charts" group. I did tests years ago...so i'm not really shooting in the dark so to speak. My main developer is Pyrocat, so if for some reason I can no longer buy it....i can make it.
Different approaches for different folks. But i'm not an eternal tester.

 

[Craig]

Personally I get the picture from the photo in Paul's post in #106.....& later where he said his negatives printed well on grade 2.

That photo has great tones doesn't it?

 

[GregY]

That photo has great tones doesn't it?

For a photo on a monitor....it was enough to entice me to order some.....

 

[ags2mikon]

Paul did a very nice job with that film. The tones are very rich. And it was a very simple process. Thanks Paul.

 

[aparat]

Craig, Thanks for the interpretation..... pretty much what i've always done without reading charts. I've always preferred the practical approach. Expose, develop, print..... tweak when/where necessary. That's why in the long run I've used the same few films and the same developer.
That doesn't mean that i didn't read Ansel's The Camera, The Negative, The Print.....or other tomes.....
Personally I get the picture from the photo in Paul's post in #106.....& later where he said his negatives printed well on grade 2.

I should have spent a bit more time writing my response, but, fortunately, @Craig explained it perfectly. What you describe is a very effective, practical way of perfecting one's exposure and development. The "expose, develop, tweak" method has worked for thousands and thousands of photographers over the years and continues to be an excellent method of getting to the ultimate destination, i.e., the fine print (or electronic image).

I agree that @paulbarden did an amazingly good job with his photograph. The tonality is gorgeous.

 

[Donald Qualls]

obscure connection to foxholes.....

Likely to protect you from the fierce battle that will ensue...

 

[pentaxuser]

I always thought that the word and meaning of " foxhole" was part of U.S. parlance. I am sure I have heard it much more often in Hollywood war films that in comparable U.K. produced films

pentaxuser

 

[Sirius Glass]

I always thought that the word and meaning of " foxhole" was part of U.S. parlance. I am sure I have heard it much more often in Hollywood war films that in comparable U.K. produced films

pentaxuser

You are probably correct, but do you really want to walk through that mine field?

 

[redbandit]

I always thought that the word and meaning of " foxhole" was part of U.S. parlance. I am sure I have heard it much more often in Hollywood war films that in comparable U.K. produced films

pentaxuser

Us poor colonials in the states learned after world war one, hiding in the ground from artilery and machine gun fire was much preferable to marching INTO it.

 

[Donald Qualls]

hiding in the ground from artilery and machine gun fire was much preferable to marching INTO it.

And individual hidey holes were preferable over trenches that gave anyone successful in crossing the gap access to all defenders, hence foxholes vs. trenches.

 

[aparat]

I finally got around to developing a roll of Kentmere 400. XTOL-R, 12 minutes in a Jobo. It could have used 30% more development, as the Holga is inherently lower contrast than a modern conventional lens. I keep forgetting that. Digitized with my phone.

 

[GregY]

Thank you aparat.... As always, a picture is worth a thousand words, dozens of graphs or references to holes in the ground...
Looks like a fine film