HP Combi-Plan 4x5 tank and agitation

[younghoon Kil]

I recently got 3 HP Combi-plan 4x5 tanks and I'm going to use this tank mainly for semi stand development.
I learned how to agitation when using this tank as a daylight tank on YouTube.

By the way, I wonder how high the film carrier should be lifted when initial agitation in the darkroom.
And do I need to tap the film carrier against the inner wall or top outer border after the initial agitation?
Also, I'd like to know the internal thread size of the outlet at the bottom of the tank.

I would really appreciate your advice.
Thank you.

[Per Madsen]

I always use pre-flush with water for a couple of minutes to remove air bubbles and anti-halation.

[younghoon Kil]

Does pre-flush mean pre-soak?

[Per Madsen]

Yes.

[younghoon Kil]

Thanks. I'll try presoak too.
I wonder how to agitate in the darkroom. :confused:

[Corran]

Put the lid on and invert several times just like a tank for roll film. Rap the tank on the counter after initial inversion to dislodge bubbles. I use this exact method in an HP Combiplan for both regular and semi-stand developing. It's just a tank, nothing special - I don't even use the fill/drain mechanisms.

[younghoon Kil]

Thanks for the input, appreciated.
The solution filling/draining time was slow, so I tried to agitate with the lid open.

[Tobias Key]

The way I have seen it done is by filling the tank with developer and then loading it in darkness, putting the lid on and then continuing in the light with normal agitation. Repeat for each step. That would fix the problem with the fill/drain times and ensure proper agitation .

[younghoon Kil]

I see your point. Thank you.

[younghoon Kil]

226790


I attached a CatLABS compensating development timer to the lid of the Combi-Plan tank.
I wanted to be less concerned about temperature changes in hot summer or cold winter. :rolleyes:
I'm only going to use this tank for semi-stand development.

[younghoon Kil]

I developed films using a CombiPlan tank as a daylight tank, but got poor results.
So I'm going to try the dip-and-dunk method described in this article.
- https://www.largeformatphotography.info/alternative-developing/

But in the bathroom with the lights off, how can I check the development time?
Can I use the darkroom timer(red and very dark screen) app for smartphones?

[Sal Santamaura]

I developed films using a CombiPlan tank as a daylight tank, but got poor results.
So I'm going to try the dip-and-dunk method described in this article.

But in the bathroom with the lights off, how can I check the development time?
Can I use the darkroom timer(red and very dark screen) app for smartphones?

I don't know the brightness or spectral characteristics of that app on your phone. I'm lucky enough to have a Zone VI Compensating Development Timer. I place its probe in the water jacket tub my three Combiplan T tanks are sitting in, and select "Film" on the timer. That renders the digital display very dark, but still visible after my eyes have adapted to conditions. It's also supplemented by an audible beep every 30 seconds. I suggest you try a bit of rubylith over your phone's screen and see whether any fogging results.

[paulbarden]

Can I use the darkroom timer(red and very dark screen) app for smartphones?

Yes, you can. I've been using the Massive Dev Chart timer for a decade and it works. (Turn your screen brightness all the way down and use the red screen)

[younghoon Kil]

Thanks for all the replies. :)
If I use a smartphone app, I would place the phone lower than the tank.

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[Daniel Unkefer]

https://live.staticflickr.com/65535/53482635296_f38fc1a514_b.jpg (https://flic.kr/p/2pu5uaE)Dip N Dunk Combiplan set up for Panchro Work (https://flic.kr/p/2pu5uaE) by Nokton48 (https://www.flickr.com/photos/18134483@N04/), on Flickr

This is my present Combiplan three tank setup, getting ready to run six sheets of 4x5 Shanghai. Will use my liter of Replenished D23. Middle tank is Wash Tank, for presoaking (haven't been doing that), water stop, and final washing too. Raising the tanks on a plastic box puts them at a good working height. I processed some Ortho film by inspection, but I am just getting going with this.

[younghoon Kil]

Looks good! :D

[monochromeFan]

Thanks for all the replies. :)
If I use a smartphone app, I would place the phone lower than the tank.

245801

I concur, film is rather sensitive to light at the wrong moment. I started my PAPER developing in the bathtub with open trays, and i used a cell phone timer app, and cell phone on the edge of the tub, and every piece of paper was ruined until i went with a regular kitchen timer in an upside down box. Then switched to paper tubes.

[seezee]

Dip & dunk is the way to go. Just make sure your darkroom is really light-tight, or use a changing tent.

[younghoon Kil]

I appreciate everyone's advice! :)

Currently I don't have a darkroom timer like Gralab timer. First, I'm going to try it with a smartphone app.