呵呵，把老辣的真身勾出来乐。

老辣兄，请教一个问题，为什么D76的PH值要定在8.6左右?而D23的PH值则只有7.8左右？ph值高低对显影有何影响？确定PH值高低的理论依据是什么？

[shhgl 编辑于 2005-06-04 11:08]

冒昧越俎代庖一把。。

2％溶液应该是2克无水亚硫酸钠＋98毫升水。

谢谢辣兄，俺现在配D72和定影已经用娃哈哈了，胶片显影液还坚持用蒸馏水，重新玩黑白以后，俺一直坚持从难从严要求自己。
现在回头看学生时代的老PP，不少内容还是很打动自己，品质可就差太多了，记得那时老用一种绿白袋的菲尼酮增感小包药，流程也是似是而非，呵呵，要是早些严格要求自己就好了。

山河好大兄

用多层离子膜反渗得到的纯净水配药，没有问题。我现在基本上就是这样用娃哈哈之类的纯净水（别用含矿物质矿泉水）

“工业用的蒸馏水，我买过几次，效果不好。请朋友一测：铁离子超标”，
－－－－－－－－－－－－－－－－－－－
好多地方都是用碳钢大锅炉烧水制蒸馏水，管道和容器都不是不锈钢。

[老辣 编辑于 2005-06-03 21:00]

值得收藏的好帖子，谢谢。

老辣兄
在D76D的硼砂-硼酸16G的基础上改变配比的方法，是很早前坛子里的“大拐扯”编译的一篇日本人的文章中提到的。要不是您的这个贴俺都忘了，呵呵
PP是39MM罗口的老徕茨5CM头拍的，感觉灰度比现代头好得多。

用马甲上张：PH值=厂家药的D76D冲的PP

柯达回答“为什么柯达的T-MAX胶卷不用于电影摄影机”

Why doesn't Kodak finish and spool B&W T-MAX Film for use in motion picture cameras?
The following information is posted to address the frequently asked question "Why doesn't Kodak finish and spool B&W T-MAX film for use in motion picture cameras"?

History
Photographers familiar with the speed/grain relationship of T-MAX technology in the still film market often question the feasibility of using T-MAX products in a motion picture system. The Professional Motion Imaging (PMI) Business Unit requested we evaluate both T-MAX 100 and T-MAX 400 as a potential motion picture film several years ago.
Kodak personnel from the Systems Group originally evaluated T-MAX in 1990 using the "standards D-96 process chemistry. Projections indicated T-MAX did NOT offer the expected speed/grain relationship. The T-MAX products did not show a significant grain improvement relative to current motion picture camera negatives, 7222 and 7231. Although we were unable to explain why T-MAX did not show the expected results, project priority did not warrant further investigation at the time.
A subsequent investigation began in 1992 after PMI personnel learned new information from Kodak B&W / T-MAX experts. The experts suggested us may need an "optimized" developer to obtain the desired speed/grain relationship. PMI personnel developed a new test plan to include D-76, which is a recommended developer for T-MAX products. Although still a low priority, Kodak pursued a partnership with Ryerson Polytechnic University in Toronto, who agreed to execute the test in their facility. The advantages to this partnership included: strengthening our relationship with film Schools; minimizing the strain on Kodak resources; and, evaluating the T-MAX product in a customer motion picture lab.

Evaluation
Kodak and Ryerson Film Institute partnered in the venture and agreed on appropriate process and exposure conditions after running time of development series and determining approximate EI ratings for the T-MAX films. The team used the "standard D-96 and Ryerson's" modified D-76 process chemistries.
The team discussed and defined five different scenes with varying lighting ratios. T-MAX and Eastman camera negative stocks were processed to the same contrast and printed onto Eastman Fine Grain Release Positive Film, 7302.
Film students and faculty from Ryerson viewed the final projections and rated each scene for granularity, sharpness and contrast.

T-MAX 100 and T-MAX 400
Conclusions:
1. The EI rating of both T-MAX 100 and T-MAX 400 in a motion picture system could be either 64 or 100. Current motion picture products are sensitometrically faster than the T-MAX products tested (See curves 1-4).
2. There is NO SIGNIFICANT granularity improvement using the T-MAX products in either the D-96 or "modified" D-76 process chemistries. This statement is supported by Kodak personnel and survey results from Ryerson students and faculty.
3. The T-MAX 400 provides greater under-exposure latitude those results in more detail in the shadow areas. However, this is achieved at the expense of "Smokey blacks".
4. T-MAX products require increased fix times (i.e. five to six minutes) to remove silver and sensitizing dye. This requirement will probably not be easily achieved with most B&W processing machines as they are currently designed.

Recommended Path Forward
PMI will not pursue further testing of T-MAX 100 or T-MAX 400 as replacement products for either EASTMAN Double-X Film (EI 200) 5/7222 or EASTMAN Plus-X Negative Film (EI 64) 5/7231 stocks. This recommendation are based on the fact we were not able to achieve the original program objective of replacing current product with off-the-shelf camera negative stocks that exhibit significantly improved granularity.

感谢老辣兄！

有没有谈谈显影液腐蚀性的？

晚上放片时不小心撒了一点D72到地上，结果地砖留下了永久的印记。

老辣兄，关于保存的经验太有用了，非常感谢。
我就一直纳闷了，又一次发现一灌三年前剩下的小瓶D76，居然用起来一点问题都没有！

还有拜托您能回答一下我前面的问题么？

SB-1a 28%醋酸水溶液配制需要把水温升高到50摄氏度，好奇怪哦。。。

F-5定影液配方：
水（50摄氏度）－－－－－－－－600毫升
硫代硫酸钠（海波）－－－－－－240克
无水亚硫酸钠－－－－－－－－－15克
28％醋酸－－－－－－－－－－－48毫升
硼酸（无水）－－－－－－－－－7.5克
硫酸铝钾（又称钾矾、明矾）－－15克
加水至1000毫升

SB-1a停显液配方：
水（50摄氏度）－－－－－－－1000毫升
28％醋酸－－－－－－－－－－125毫升

青萍：

给你贴一份原汁原味的柯达F-5定影液和柯达SB-1a停显液的配方，最常用的。
既可用于胶卷，也能用于相纸，

关于28％的醋酸溶液配置方法：3份冰醋酸（98％以上醋酸）＋8份水。