HC110- I made a mistake but everything was fine?

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Yesterday I mixed a solution of HC 110, what i thought was dilution B. I developed my 4x5 T-max 100 negs for the recommended time (9.5 min. at 68 deg)and my negatives came out much like I expected. Good contrast, nice grain. Pretty much how I expected them to come out. Today I was reading more about HC 110 and noticed that I accidentally mixed the solution wrong. I mixed 16oz. of HC with 112oz. of water. Now this is 1:7 ratio but certainly not dilution B. Dilution B is 1:31 from concentrate. Can somebody explain my rookie mistake and why everything came out great? I'm confused, thanks B.

-- Brian Bullen (ImABulley@aol.com), October 06, 1999


Two sources of confusion. When you say you mixed 16oz of HC110, is that 16 ozs from the liquid concentrate as it comes out of the bottle or is it from the stock solution you make by mixing the stuff from the bottle with water as suggested in the instructions? The 1:31 figure is for the slurry straight out of the bottle. The 1:7 is for the intermediate stock solution you prepare by diluting the concentrate (slurry) from the bottle with water. The two are identical and are dilution B. The only difference is that the concentrate is very concentrated i.e., active and that is why Kodak recommends the intermediate stock solution - small errors in making up your dilution B will not affect the activity as much if you use the stock solution instead of the concentrate.

If that is not the source of the confusion and you did make an error (i.e., you did make the mistake of mixing 1:7 from the concentrate instead of the stock solution), I'm guessing you still got 'good negs' because you're processing Tmax. I do not know what the recommended times are for T Max but I do remember that Kodak recommends a temperature of 75F. So, if you did mix the developer to a higher concentration (more activity), you also processed for the same time at a lower temperature (less activity) and I'm guessing those two errors cancelled each other out.


-- N Dhananjay (ndhanu@umich.edu), October 06, 1999.

Mr. Dhananjay I mixed 16oz. of HC110 concentrate to 112 oz. of water making one gallon of solution. I checked my times again and the Kodak Dataguide recommends the time and temp. that I used as the "ideal". I'm still confused because the solution I used was obviously too strong. I guess I owe this one to luck. Thanks for the response. B-

-- Brian Bullen (ImABulley@aol.com), October 07, 1999.

Have you printed the negs yet? I would guess that if all other variables were under control, you really have overdeveloped the film. You may very well find that you need to use a lower grade paper or filter to get a really nice print.

Overdeveloping is not usually the best idea, but unless you go WAY over, it's rarely a total disaster.

-- mike rosenlof (mike_rosenlof@yahoo.com), October 07, 1999.

I got back and checked the times last night. I'm afraid I was wrong - the 75F is the recommendation for using TmaxRS developer. HC110 is 68 F. However the recommended time is 7.5 mins (at least in my copy of the Kodak dataguide). So it sounds like you've used a higher concentration and possibly deeveloped for a longer time as well. I think I would agree with the previous post. Many of todays emulsions have very long straight line portions. This means that the neg will show nice separation of tones and can be mistakenly interpreted as looking OK and containing all the information you need but of is actually overscaled for the density range a paper can handle. I'm guessing your negs are either going to be difficult to print or you have compassionate gremlins in your darkroom... DJ

-- N Dhananjay (ndhanu@umich.edu), October 07, 1999.

If you are new to TMX, you may have also underexposed, which, coupled with the overdevelopment, would end up looking sort of normal.

Most of the people I know who shoot TMAX shoot it at 50. I gave up on the stuff entirely.

-- Erik Ryberg (ryberg@seanet.com), October 07, 1999.

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