Emulate Xtol replished with one-shot--why not?

[radiant]

This website specifies one formula which should be in par with Ilford: http://bandicoot.maths.adelaide.edu.au/develop/develop.cgi - I found that the α is -0,1.

 

[radiant]

@vedostuu keep in mind that Ilford's table is built based on other Ilford's recommendations. Their table assumes Ilford's agitation: 4 inversions during first 10 seconds, followed by 4 inversions every subsequent minute. This is quite different from continuous inversions for first 30 seconds, followed by 2 inversions every 30 subsequent seconds (common practice, IIRC this comes from Kodak's data sheets?).

Oh wow. Ilford doesn't want to give good kick at the start? I've been doing first 30 seconds and agitations every minute.

Maybe this just gets way too complex..

BTW: Massive Dev uses also Ilford formula https://www.digitaltruth.com/devchart.php?doc=timetemp

 

[relistan]

I try to ask again: Is anyone compensating the development time based on developer temperature or is bathing the developer jug to 20degC only way to get to correct temperature before development?

I don't replenish, I just use stock one shot. It still takes me 6-7 months to go through a batch. I can afford €25 a year on developer. In Ireland it's hardly ever warm enough to just develop at room temp (chems sit in a less heated part of the house) so I usually use a hot water bath to get the developer up to 20C. But sometimes I adjust for temperature instead if it's already pretty close. Then I use the Ilford chart for that.

 

[john_s]

This website specifies one formula which should be in par with Ilford: http://bandicoot.maths.adelaide.edu.au/develop/develop.cgi - I found that the α is -0,1.

It's not hard to make the formula more specific to a particular developer and film combination if you have data points that someone has ascertained for two temperatures. I can post an Excel spreadsheet if anyone is interested.

 

[MattKing]

It seems unlikely to me that partially used developer that has development byproducts added to it would yield the same characteristic curve as fresh developer without byproducts, but as I don't own a densitometer, I can't supply data about that.
I believe I notice a difference between film developed in stock X-Tol and film developed in replenished X-Tol.
My eyeball comparisons are based on films where the mid-tone contrast appears to be the same, but as I said, I don't own a densitometer.
And I definitely recommend adjusting development time to the ambient temperature. I use the Development Dial in the Kodk Darkroom Dataguide, and it has always served me well.
FWIW, I like "38" for the T-Max 100 and T-Max 400 films in replenished X-Tol. After 30 seconds of continuous rotary agitation, I agitate 5 seconds each 30 seconds (inversion). I use 70ml per roll of replenishment.

 

[john_s]

Is it the case that replenished Xtol produces a lower film speed than fresh single use Xtol? Some replenished systems behave like that, and I'd expect Xtol to do so, especially as the replenisher for Xtol is just new Xtol. Many replenisher formulas include extra alkali and extra developing agents in order to keep the replenished system closer to new.

 

[Sirius Glass]

"Stock Xtol produces identical results to replenished Xtol". I disagree. Replenished XTOL gives much better tonality, tonality smoothness, and better sharpness. Otherwise I would not go to the trouble. Stock XTOL does not produce identical results to replenished XTOL.

I prefer to use XTOL replenished. All I could say that the image is "mellower". The contrast seems slightly different than one shot XTOL. I use HC-110 replenished. I got an old batch from Ebay. To me, film in seasoned developer looks better. It's more economical too.

It seems unlikely to me that partially used developer that has development byproducts added to it would yield the same characteristic curve as fresh developer without byproducts, but as I don't own a densitometer, I can't supply data about that.
I believe I notice a difference between film developed in stock X-Tol and film developed in replenished X-Tol.
My eyeball comparisons are based on films where the mid-tone contrast appears to be the same, but as I said, I don't own a densitometer.
And I definitely recommend adjusting development time to the ambient temperature. I use the Development Dial in the Kodk Darkroom Dataguide, and it has always served me well.
FWIW, I like "38" for the T-Max 100 and T-Max 400 films in replenished X-Tol. After 30 seconds of continuous rotary agitation, I agitate 5 seconds each 30 seconds (inversion). I use 70ml per roll of replenishment.

I am not the only one to see the difference. As in the Life cereal tv advertisement, "Try it. You will like it. Even Mikey likes it."

 

[radiant]

I don't replenish, I just use stock one shot. It still takes me 6-7 months to go through a batch. I can afford €25 a year on developer. In Ireland it's hardly ever warm enough to just develop at room temp (chems sit in a less heated part of the house) so I usually use a hot water bath to get the developer up to 20C. But sometimes I adjust for temperature instead if it's already pretty close. Then I use the Ilford chart for that.

I don't see any point either when shooting 135 or 120 films. But when developing 5x7" sheets in paterson, three sheets need 1.5 liters of developer. I don't count money in this (I'm not rich) but wasting such amount chemicals (and collecting those to recycling) is just crazy.

I think developers are holy grails to many and that's just fine. There are many other things to worry. If developer XYZ with method ÅÄÖ makes you achieve your goals, then there is should be no further questions.

 

[MattKing]

I don't see any point either when shooting 135 or 120 films. But when developing 5x7" sheets

If large format is part of your toolkit, it makes sense to use replenished developers with it. And if you use 120 and 135 films too, it makes sense to use the same developing regime for each format.
In my case, I just like working with replenished developer, and being able to easily work at ambient room temperature for everything I do.

 

[radiant]

It's not hard to make the formula more specific to a particular developer and film combination if you have data points that someone has ascertained for two temperatures. I can post an Excel spreadsheet if anyone is interested.

Well, it sounds hard but please share your method!

I use the Development Dial in the Kodk Darkroom Dataguide, and it has always served me well.

Could you check few times with that so we could see if there is difference to Ilford method?

For example 6 minutes 20degC -> 21degC and 20 degC -> 24 degC ?

 

[MattKing]

Could you check few times with that so we could see if there is difference to Ilford method?

For example 6 minutes 20degC -> 21degC and 20 degC -> 24 degC ?

I'll do this tomorrow morning.

 

[reddesert]

I've been using the developing dial calculator in the Kodak Darkroom Dataguide since my uncle gave me one when I was about 14, and I'm sure it is less variable / more accurate than other parts of my developing process. I live in a place where the tap water temp changes a lot over the year, so it's very helpful.

For 6 min at 20 deg C -> the Kodak dial says 5.5 min at 21 deg C, and 4.5 min at 24 deg C.

Bear in mind that timing development accurately so as to worry about the difference between 5:30 and 5:46 as mentioned above in post #36, would require strict control of matters like your pour-in and pour-out times. I develop in daylight tanks and don't think I can control this to 15 seconds, plus frankly I just don't care to. I prefer dev times over 6 minutes so I don't have to get stressed about matters like this and how long it takes to get the stop bath into the tank.

(I have about four Darkroom Dataguides now - some people collect Leicas, I collect Dataguides. The developing calculators are all the same AFAIK, but the stock photos on the delightful examples of long-discontinued paper surfaces are different.)

 

[radiant]

For 6 min at 20 deg C -> the Kodak dial says 5.5 min at 21 deg C, and 4.5 min at 24 deg C.

Ilford formula gives 4 minutes at 24 deg C. Which is bit weird because Ilford first agitation is so short..

I agree that 15-30 seconds might not make any visible difference at all. Most of the action happens anyways in first few minutes, then it slows down. I developed by inspecting (n IR light) and noticed this myself.

 

[Donald Qualls]

That doesn't seem to be in line with ilford graph (https://www.ilfordphoto.com/wp/wp-content/uploads/2017/03/Temperature-compensation-chart.pdf). For example 20degC 6 minutes in 21degC should be 5.5 minutes. If you reduce time by 4% you end up in 346 seconds or 5 min and 46 seconds. Ilford graph says it should be 5 min 30 seconds.

I'm just telling you what I've done. Pretty sure I originally got that figure from a Kodak document, but it might have been forty-plus years ago.

And honestly, the difference between 5:30 and 5:45 at the same temperature is negligible unless you're doing sensitometry. If you're printing, you'll never notice it; there will be more variation between one negative and the next on the same roll unless you're shooting something like product photography (which is almost never done on film any more) with 100% controlled lighting.

 

[radiant]

I'm just telling you what I've done. Pretty sure I originally got that figure from a Kodak document, but it might have been forty-plus years ago.

No no, don't get me wrong. Thank you for sharing. I was just writing aloud my observations. 15 seconds in development time doesn't change anything, you are absolutely right.

 

[MattKing]

Nothing like a photo...

 

[Mainecoonmaniac]

Nothing like a photo...
View attachment 273229

Timeless and useful tool. Take care of it. Now I gotta look for one on Ebay.

 

[MattKing]

Timeless and useful tool. Take care of it. Now I gotta look for one on Ebay.

Warning - many of them are in editions that include a whole bunch of different Kodak printing paper samples. Looking at them may make you weep!

 

[john_s]

...

Well, it sounds hard but please share your method!

....

This spreadsheet does what the Ilford graph does except that, unlike the Ilford graph where every line on the semi-log paper is parallel and the same for every film and developer combination, it takes time and temp figures at two known points (for example from a manufacturer's table for a film and developer combination) to calculate the theoretical gradient of the graph. You don't need to read the gradient though.

Then you insert your own previously ascertained time (possibly different to the manufacturer's time) and the temperature at which you determined that time, then insert the new temperature and the spreadsheet shows the calculated new time. This is merely a better method of interpolating than just doing it linearly.

There are a couple of extra bits on the spreadsheet that are not essential (degF to degC conversion, a display of the coefficient that's built into the equation)

There is an example in the spreadsheet. I wanted to use the Gordon Hutchings temperature corrections in his PMK book for my chosen film, but I had determined a different time. I had to develop at a different temperature so the spreadsheet adjusted my own personal time to a new temperature. So it was my time but adjusted using his correction figures.

This all assumes that the time varies exponentially and that is a safe assumption for our normal range. You could also use the formula to extrapolate but it might stretch the assumption.

 

[SchwinnParamount]

@Sirius Glass Here we go: Delta 400 scanned at the same settings. Half of these are replenished. Time to instantly recognize the superior tonality! Ready! Set! Go!

https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/maru-sushi.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/closer-portrait.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/deville2.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/hello-o-o.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/kids-and-cannon.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/reader.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/masked-dogwalker.jpg
https://d3ue2m1ika9dfn.cloudfront.net/xtol-test/on-the-edge.jpg

The ones with dogs. Yeah, that's it. Dogs are so replenishing so it must be them. Oh, and the one with the bridge.

 

[radiant]

This spreadsheet does what the Ilford graph does except that, unlike the Ilford graph where every line on the semi-log paper is parallel and the same for every film and developer combination, it takes time and temp figures at two known points (for example from a manufacturer's table for a film and developer combination) to calculate the theoretical gradient of the graph. You don't need to read the gradient though.

Thanks for sharing. That is the tool for finding the alpha for this formula http://bandicoot.maths.adelaide.edu.au/develop/develop.cgi too? I guess?

Nothing like a photo...

Does it come with instructions? I have to admit that I don't understand that at all

 

[mshchem]

Sorry, I was a bit unclear. I mean how do you bring the developer to that temperature before developing? Or do you all have darkroom with constant 20 degC temperature?

In the warmer months my darkroom stays 66 to 70° F. In winter I use a small electric heater on the lowest setting to help. I have thermostatic mixing valves. If the solution is too cold I use a microwave. It only takes a very few seconds.
There's Kodak published times for various film temperature combinations.

 

[mshchem]

What matters most is consistency. Standardize on a temperature that is relatively easy to maintain (barring extremes). For most B&W processing a temperature between 18C and say 24C should be fine, although it is generally/usually best to avoid developing times shorter than 5 minutes.

Particularly when developing film (as opposed to paper), try to keep the temperature of the whole process relatively constant if possible. This usually means standardizing on the wash water temperature.

This is the way I do things. Always have. It's good lab practice. Start to finish keep temperature constant.

 

[reddesert]

Does it come with instructions? I have to admit that I don't understand that at all

It's very simple in practice. Understand that the dial - the green part in Matt's photo - rotates with respect to the white page. You look up a development index in a table, such as 40 for Tri-X in D-76 1:1, or 33 for Panatomic-X in Polydol. Then set the "normal" arrow to the development index on the left, and read off time vs temperature on the right. If you don't know the development index but have a manufacturer's recommendation or a time for 68F/20C from the Massive Dev Chart or whatever, you can set that time+temp on the right and infer the development index, and read off different time/temp combinations.

There are some extra tables with numbers to add to the index to adjust time (basically, adjust contrast) for condenser / diffusion enlargers, paper grades, and so on, but I mostly use it for the time/temp adjustment.

 

[mshchem]

Warning - many of them are in editions that include a whole bunch of different Kodak printing paper samples. Looking at them may make you weep!

This is the truth. Opal, Ektalure, Medalist. 3 or 4 base colors, had to be close to a dozen different surfaces

Dbl. Wt. Ektalure G and K surfaces

I found my bottle of Kodak Developer Starter soln. Cat. No. 1466382, came in quart bottles. It's got two ingredients sodium bromide and sodium chloride, that's listed on the bottle. I've never used it. This is the original starter to make a fresh "tank solution", to season the developer to mimic replenished XTOL, mostly used in big operations along with, test strips densitometer, pH and specific gravity . I'm like you folks I just added 70mL per roll, tossed the excess.
The first couple runs you might notice a bit harder negative but nothing difficult to deal with when printing