tech pan, apx25, and tmx100 ??

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Wondering if anyone has carefully compared APX25 with TMX100? Where does APX fall between tech pan and TMX with respect to grain and contrast? The reason I ask is because I have been doing portraiture with Tech pan (35mm) and getting a very good result. However, I could do without the special developing and the filtering (cyan) necessary to correct for the extra red sensitivity.

-- steve vancosin (steve1chsn@aol.com), January 10, 1998

Answers

Tech Pan has an RMS grain rating of "5," APX 25 is a "7," and TMX is an "8," so Tech Pan has the edge in grain. It has an even greater edge in resolution: Tech Pan has a low contrast (1:6) rating of 200 lp/mm vs TMX's 125. At high contrast (1:1000), TMX and APX 25 both claim 200 lp/mm while Tech Pan is at 300.

Regarding contrast: developed in Photographers' Formulary TD-3, Tech Pan gives very smooth results at an ISO of 50. APX 25 is very close developed in XTOL 1:3. For me, TMX (in XTOL 1:3) is a definite third. While grain is similar to APX 25, TMX seems to have less exposure latitude and a bit more contrast, making it touchier to work with.

-- Brian Hinther (BrianH@sd314.k12.id.us), May 22, 1998.


Tech Pan has the finest grain processed in Technidol, with good but not excessive contrast. Because of its red sensitivity the tonality in portraits can be odd. The discontinued APX25 has excellent resolution. I have processed it in Rodinal 1+25 and TMax developers. As you would expect, Rodinal gives a slightly grainier, but very sharp negative with excellent detail, fine for scenic work. Overall, for general photography, I prefer TMX100. The grain is fine, and the tonal range outstanding. It develops very well in TMAX developer, which gives similar results to XTol.

-- Fred Rupert (frupert@prodigy.net), June 18, 2001.

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