niall_church Posted March 5, 2007 Share Posted March 5, 2007 what would the effect be on a roll of film developed on warm chemicals,if one did not lower developement times! Link to comment Share on other sites More sharing options...
Craig_Cooper11664875449 Posted March 5, 2007 Share Posted March 5, 2007 hmmm... over development.... Link to comment Share on other sites More sharing options...
carl_bretteville Posted March 5, 2007 Share Posted March 5, 2007 Depends on what 'warm' means. A few degrees above 20c/68F primarily speeds things up. As long as you stay above +/-5 minutes development time it should be OK and have a good chance of evenly developed negatives. I often use 21 or 22C as thats the ambient temperature in the room I use for neg development. On the other hand if warm means a lot warmer you can end up with the film being cooked and emulsion crackled or separating from the film base. Link to comment Share on other sites More sharing options...
Craig_Cooper11664875449 Posted March 5, 2007 Share Posted March 5, 2007 <i>...21 or 22C ... I use for neg development. <p> On the other hand if warm means a lot warmer you can end up with the film being cooked and emulsion crackled or separating from the film base.</i> <p> It would need to be a <u>lot</u> warmer... I live in Singapore and the cold tap water is 29C. A number of people here develop at that temperature regularly with no ill side-effects. However, personally, although I have developed at 29C previously, I prefer to work around 25/26C primarily to get times above the 5~6 minute mark and have never had film issues from development temperature. Link to comment Share on other sites More sharing options...
ronald_moravec1 Posted March 5, 2007 Share Posted March 5, 2007 Film grain is larger the higher the temp even if you compensate time to achieve the same gamma or contrast. The change is small and requires careful looking witha grain mag under the enlarger, but it is there. I went back to ice and the refrigerator to cool things down before developing in the summer. 15 minutes will get the developer and fix down if in small bottles. Link to comment Share on other sites More sharing options...
raymond_tai Posted March 5, 2007 Share Posted March 5, 2007 I also like in a city where the room water temperature is very warm. Lets say it is 29C. Is there a time adjustment formula if the table on the film box or developer only has times for 18C and 22C? Link to comment Share on other sites More sharing options...
raymond_tai Posted March 5, 2007 Share Posted March 5, 2007 ...live in a city...(sorry for typo)... Link to comment Share on other sites More sharing options...
Craig_Cooper11664875449 Posted March 5, 2007 Share Posted March 5, 2007 Raymond, Somewhere on the Ilford site there are/were times for temp adjustments. Once upon a time I made a graph out them which is what I use to make adjustments - see the attachted spreadsheet. Link to comment Share on other sites More sharing options...
wigwam jones Posted March 5, 2007 Share Posted March 5, 2007 The answer is that it depends. Just about every film manufacturer and every developer has a temperature compensation chart, with reciprocity numbers above and below certain points. Some developers are panthermic and will work within a range of temperatures without changing their qualities. Beyond this, if the chemicals are sufficiently hot, they will dissolve the emulsion, ruining the film. If there is sufficient difference between temperatures of say, developer and rinse, your film could suffer reticulation. Therefore, it is best to follow manufacturer's recommended guidelines, unless you are sure of the ground on which you tread. If you must depart from the recommended temperatures, use the charts provided online by most manufacturers to alter the dev times accordingly. Most of this has been thought of and worked out for you over the years, and the information is easy to obtain in most cases. Link to comment Share on other sites More sharing options...
skygzr Posted March 5, 2007 Share Posted March 5, 2007 Craig - Won't exposing film to durian vapors also cause the emulsion to crack? :-) Link to comment Share on other sites More sharing options...
chris_waller Posted March 5, 2007 Share Posted March 5, 2007 As a rule of thumb development increases by 10 percent per degree C increase in temperature. Once upon a time when emulsions were softer, if the temperautre strayed above 25 C, the emulsion would buckle and even detach from the base. Modern emulsions are much harder and will take higher temperatures - but devving at 29 C - wow! Link to comment Share on other sites More sharing options...
roger krueger Posted March 8, 2007 Share Posted March 8, 2007 Depends on the film. When I tested Ilford Delta 3200 in warmer temps I found it started losing shadow speed into fog past 22C. Whereas TMZ was fine up to at least 32C. Whatever temp you develop at, be sure the fix is at a similar temperature. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now