is there a percentage increase on Ilford and Kodak times to aim for such as 10%
With something like this, I assume?
https://www.ebay.com/itm/160Pcs-PH-...078395?hash=item5d86d535bb:g:GTMAAOSwBLlVNLg5
That type sucks. I've tried a few and variations between individual specimens were huge; as large as 1.00. (Referring to the yellow or blue stick-like instrument. The cylindrical type is better)
That type sucks. I've tried a few and variations between individual specimens were huge; as large as 1.00. (Referring to the yellow or blue stick-like instrument. The cylindrical type is better)
I'm sorry, I'm not sure I follow. Does this graph mean that, let's say, what can be achieved with D-76 in 8 minutes, takes up to 14 minutes with HC-110? Or am I missing something?Kodak tells it in the datasheet, they plot contrast index vs development time. You have graphs for different processing conditions: small tank, large tank, trays and rotary:
View attachment 248098
With that you get a good guess for kodak products. Some graphs are a bit inconsistent, but still it shows how the CI grows with development time for each film-developer.
With ilford you have to experiement a bit, no problem.
Yeah, I see.Yes... this was a "search". One has to read opinions from customers to find a good model.
Yeah, I see.
My experiences so far with this type are good. It's fast, seems consistent and measures some more things besides pH:
https://www.wish.com/product/5e09e123672a5555d28ab1bb
It's available from a variety of sellers, but in the end it's apparently just a fairly generic Chinese consumer product that happens to work OK.
I'm sorry, I'm not sure I follow. Does this graph mean that, let's say, what can be achieved with D-76 in 8 minutes, takes up to 14 minutes with HC-110? Or am I missing something?
I was double-checking, because D-76 seems to achieve same contrast index as other developers, but does it faster. My thought (apparently incorrect one) was that D-76 is a neutral developer.Yes... some developers are faster than other, also see that Xtol sotck is faster than 1:1, not a surprise.
Reading that graph is quite straight, first you have a graph for each "tank type", so first you have to look at the right plot. Then the thing is easy, just take the curve for your developer and for each development time it says what Contrast Index you will get.
Remember that those graphs are starting points, developer age, particular agitation, temperature precision... all that has an influence, mostly those graphs show how CI grows with extended developer time.
I was double-checking, because D-76 seems to achieve same contrast index as other developers, but does it faster. My thought (apparently incorrect one) was that D-76 is a neutral developer.
Thank you! I read it but my mind is not clear enough right now. I'll get back to it when I'm off duty. Either way it seems I'll have to sacrifice a couple of rolls.
To my mind, wimpy negatives are under-exposed negatives, not under-developed ones.At last someone who prefers healthy negatives (versus wimpy negatives)
I'm not sure what would make a developer "neutral".I was double-checking, because D-76 seems to achieve same contrast index as other developers, but does it faster. My thought (apparently incorrect one) was that D-76 is a neutral developer.
Sure, I have this non-inversible tank which has a wiggly thing in the middle and it doubles as a thermometer. It's not the best solution, but it gets the job done. I always develop at 21-22 celsius, that would be a little more than 68F. Tank is plastic and it keeps the temperature quite well as long as ambient temperature is adequate.Are you developing with some form of temperature control? Lower than 68F can result in some underdevelopment and flatness/lack of contrast. I have no problem getting good contrast negatives with stock D76 at the recommended times and agitation, shooting box film speed, and using a simple system of temperature control with a small insulated cooler.
Everything is "relatively useful" in this life, once we learn how to do things by the book, we start thinking outside the box. At least now I know what to do with my next roll and I'll be more prepared for surprises.Yes... the graph shows that you can reach any C.I. with any developer, but each developer does it with a particular speed.
In fact developer makes several things, but each soup makes each thing at different speed. First a developer has an "induction time" before a significative development starts. Later developer has to start developing exposed crystals which takes place more or less faster depending on agents REDOX potential and etc, but another process we call "infectious development" that develops non exposed crystals that are close those developed yet, pH is an important factor for that infectious developing speed. The silver solvent also has interactions with all that...
Well, with all developers we may obtain a low or a high C.I. , the question is about the nuances, some will show more or less grain for the same C.I. or more or less fog...
Those graphs in the Kodak datasheets are only relatively useful in practice, but the important thing is that they conceptually show how processing can be adjusted and what C.I. sensitivity we have to development time.
I got lost in translation. I meant it's a "leveling developer", which has relatively low pH and ensures a "leveled" contrast for sake of pulling out shadow detail. In other words, "not a high contrast developer by default". I don't know if it makes sense, most of my literature is in Яussian.I'm not sure what would make a developer "neutral".
All developers are different. Each developer will have standard times for particular films, and those times will be dependent on a bunch of criteria, including the desired contrast.
And if a combination of film, developer, scanner and scanner software combination doesn't typically give you files that look pleasing to you, check to see whether your scanning software allows you to record a set of standard adjustments in a profile. Then make those adjustments, record them, and use that profile for that combination.
I have read how dilution affects sharpness and grain, but I had no info about contrast. That is why I opened the thread about contrast, not about sharpness or grain, both of which I can control.
Doremus, this is right, but extending development time also affects the appearance of the grain, coarser.
To my mind, wimpy negatives are under-exposed negatives, not under-developed ones.
Under-developed negatives are just quiet.
If that is so, then I'm afraid I'm a complete dunce in this subject.Adjusting contrast with a change in developer dilution or development time is basic to analog photography. I assume that anyone who is developing his/her own negatives has learned this already. If you hadn't, then I apologize for the incorrect assumption.
If that is so, then I'm afraid I'm a complete dunce in this subject.
If that is so, then I'm afraid I'm a complete dunce in this subject.
Scanning throws a whole bunch of other variables into the mix in the form of automatic adjustments by the scanning software, etc.
Adrian, can you amplify what you have quoted in my first two sentences above. What is the standard by which you are judging the high side i.e high side of what as you then go on to say that both are below ISO contrast
I checked your times on your website and for HP5+ in replenished Xtol at 75F you quote 7 mins which is a 10% increase on what Kodak gives for 75F as it quotes 6 mins 15secs so I can see that your times will give a greater contrast that Kodak's own times. I am assuming in this that replenished Xtol for the purposes of time comparison is the equivalent or as near as damn it the equivalent of stock Xtol
The puzzle arises when we look at Ilford's times for Xtol. Ilford's time is 8 mins Xtol @ 68F which on Ilford's temperature compensation chart drops to about 5mins 30 sec. Ralph Lambrecht's chart show it as 8 mins to 5 mins so a slight further reduction. However what stands out is that the Ilford time for stock Xtol at 75F is actually less than the Kodak time by 45 secs which at the time quoted is appreciable.
So based on these times it would appear that Ilford's time should result in a lower contrast than Kodak's which seems contrary to the point you makes when you say Ilford tends to be on the high side
Finally can I ask what is ISO contrast compared Kodak or Ilford contrast in terms of numbers and if users want to aim for ISO contrast how is this worked out and for those not able to do the maths is there a percentage increase on Ilford and Kodak times to aim for such as 10%
Thanks
pentaxuser
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