Tri-x @1600 using Microphen, for how long?

[Yvon]

I've googled for the whole night since I came back from photo lab with my chemicals. Film market is shrinking as retailers told me they were afraid of stocking too much chemicals if the sales could not get better. So I didn't get my R09, instead, I bought Microphen for my Tri-x.

The reason I chose Tri-x is very simple. I got scared by someone saying HP5+ can easily produce grains comparing to Tri-x. I've previously used HP5+ and haven't noticed much else except the high contrast. Anyway, since I've doing well with Tri-x, so Tri-x it is, I brought it home.

Now I have a problem.

I've already pushed my film to 1600, and the only thing in hand right now and in a foreseeable future is this Microphen, good for pushing HP5+.

So I have to try this combination.

I found this page:
photo.net/black-and-white-photo-film-processing-forum/00BEhG

Stefano mentioned his specs at the bottom of the very nice photo. 16' in stock. I would like to try it as a start point for a series of experiment for this combination and optimize it if possible.

My question is, Has anyone done similar things before? Is it worth of trying at all? And, if there is a possibility that it can be optimized, must it be in stock solution?

Since this is my first time developing film and I am caught in this peculiar situation, please give me some hint.Your input will help me through this journey, and it is highly appreciated. Thank you.

 

[Colin Corneau]

Google the Massive Development Chart, punch in your film and developer and have at it. And stop getting alarmed so easily.

 

[Colin Corneau]

Here yah go:

http://www.digitaltruth.com/devchart.php?Film=Tri-X+400&Developer=Microphen&mdc=Search

 

[john_s]

..... I've previously used HP5+ and haven't noticed much else except the high contrast.......

Tri-X in Microphen is an excellent choice for pushing.

Your comment about your experience of the contrast of HP5+ indicates that development was possibly too long. Generally, films produce a wide range of contrast according to development time. You can get low contrast from HP5+ by giving generous exposure and just enough development (perhaps a bit less than normally recommended).

The issue is important when trying to achieve an exposure index of 1600. Either you overdevelop a 400 film, or choose one of the "3200" films which are actually more like 1200 films in reality. The former will give higher contrast (and smaller grain) than the latter. It's worth trying both approaches, and then you will know.

 

[ARCHIVIST]

Keep in mind that Microphen is designed to allow for a 1/2 stop increase in film speed.

For example that is why it suggests exposing FP4 at 200 ISO instead of its nominal 125 ISO.

I have always found Microphen to work well with most films at 1:3 - especially HP5 rated at 800 ISO.

Try and avoid processing times in excess of 20 minutes as you run the risk of chemical fogging.

Regards
Peter