Primer on pushing film

Hello all. I got back into photography a year ago after a very long hiatus. I used to know the basics of pushing film, but that was one thing I did not retain.

Any where I can get a primer on it? I shoot 100 speed usually (generally Fuji Arcos), and want to push it to 400 or so.

Try a speed developer like Acufine or Microphen, and you can usually get one or two stops of additional speed measured as shadow detail. These developers will increase shadow detail with underexposure without letting the highlights get out of control. Compensating developers and techniques like stand development or reduced agitation can also increase speed.

The common belief that you can increase film speed by as many stops as you want just by extending development in any developer isn't really correct. Extending development will increase contrast, but not real film speed.

There are some pretty nice 400 speed films out there. Might give those a test.

As David suggests...pushing Acros doesn't seem all that logical considering the existing 400 speed options out there.

Getting 2 whole stops out of Microphen seems like a lot to me. I get a usable 560 out of TXT in Microphen, maybe 640, so that's only 1/3-2/3 of a stop. But I shoot TXT at 1600 and 3200 all the time. The nice thing about Microphen is that it doesn't build contrast as quickly as you'd think, so you can extend development quite a bit.

In fact, I accidentally mixed up my tanks of TXT @ 6400 and Delta 3200 @ 3200 and souped the latter in Microphen for 35 minutes. Yet...amazingly...the images from the Delta 3200 is quite manageable, contrast-wise. Grain is really big, even for Delta 3200, but contrast is okay.

allan