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-- yee law (yands@vtcinet.com), December 02, 1997


Used the Combi Plant Tank for a 4x5 class that I took at community college. From my limited experience,

Pros: Allows you to work in daylight once you've loaded the film in the k, supposedly reduces scratching the negative, easy to use and load.

Cons: Cheap plastic construction, expensive (about $45 from Adarama and B&H), can only process 6 negatives at a time.

As I said, I used it (and purchased a tank) for use during my course and I only used it (I didn't do tray developing so I don't know what that's like). I will continue to use the tank when I process 4x5 negs. The tank can also be used for other negatives (smaller) but the size escapes me.

Feel free to e-mail me with additional questions.

-- Stuart Goldstein (satgre@worldnet.att.net), December 08, 1997.

I've received several e-mails about getting more information about the Combi tank, so I'm posting it here. Some of it, I'm quite sure, is redundant.

To the best of my knowledge, there's no information on the internet about the Combi Tank [other than this forum]. However, I didn't search for information.

As I may have mentioned in my postings, I was taking a LF course last fall at a community/junior college here in NJ. At that time, the instructor presented us with different options for processing the 4x5 negative. Of course he presented tray development. Like yourself, after seeing the demo for tray developing, I decided that I didn't want to process that way (besides putting your hands in the chemistry, there was also the chance of scratching the emulsion during tray dev).

He also showed us several tanks that we could use. I know that he showed us the Combi and the Yankee tank. Of all of the tanks that he showed us, the combi looked like the easiest to use.

You use the Combi in the same way that you use a 35mm daylight tank. The combi can process a max of 6 negatives at a time. It loads sort of like a toaster, three negatives on each side of the negative careier. I use my dev (D76) straight, agitate for the first 30 seconds, then 5 seconds every 30 secs. As I said, it's exactly like processing 35mm film.

I know nothing about the tube [somebody asked about a particular tube to do the processing]. I consider myself an advanced amateur. Somebody with more experience might have more info.

You can call HP Marketing directly (the combi distributor in the US) at 800-736-4373 (I think) or 800-735-4373, or 800-708-3713. Their toll number, if you're out of the US, is 201-808-9010 (the area code may have changed, if so try 973).

-- Stuart Goldstein (satgre@worldnet.att.net), February 24, 1998.

I've used the Combi Plan 4x5 film processor for several years. I bought it so I could process B&W film without a darkroom while on photographic trips. It does allow one to load up to six sheets of 4x5 film inside a dark bag, and process them in daylight--just like 35mm/120 roll film.

Pros: 1. Light, packs easily. 2. Relatively simple to load once you get the hang of it. 3. Inexpensive, so if you really don't like it you can give it away.

Cons: 1. It leaks at the lid and the screw-in drain spout. (this could be a problem with my tank only) 2. Loading sheets with the little, removable sheet film guide can be a pain; the little film hold-down clip is also a pain. 3. Pour-in funnel is too small, considering the amount of chemistry needed to develop film; it tends to spill and leak. 4. Tank requires too much chemistry (about 36 oz.) to fill tank. If you only have two or three sheets to process, it's not very economical. 5. Tank takes forever to fill and drain. It's difficult to be precise with development times with this system. 6. Lots of little, delicate, easily-lost parts. If you leave one at home, you're screwed. 7. Processing of film (IMHO the most important thing!) is just so-so. If you're not too fussy about precisely controlling each sheet of film's development, then this is the tank for you.

Tip: Get the BTZS 4x5 film tubes. I no longer use the Combi Plan system, these tubes are outstanding. I can load them in a dark bag much more efficiently. They are extremely well designed and manufactured--simple, no leaks, light tight. They require much less chemistry. They pack easily. No fussy little parts to lose or forget. Excellent results for those interested in precise zone system development. They do cost a bit more, but quality and good design always pays for itself in the end

-- Sergio Ortega (s.ortega@worldnet.att.net), March 30, 1998.

The combi does leak if YOU don't close the valves properly. I've never had problems with the lower valve if I've mounted it on the tank properly. The top valve has an "open" and a "close" setting. You turn the valve counter clockwise to pour liquid into the tank and to force air into the tank when you're emptying the liquid. Before you agitate, make sure that you turn the valve COUNTERCLOCKWISE to close the valve (I don't have leakage problems as long as I close the valve).

The funnel is small, but if the top valve is set to open and you pour the chemistry carefully, you won't spill. It does take some time to fill, but a larger funnel would probably change the center of gravity and cause the tank to tip over.

The Combi does have a lot of small parts. But like anything, if you pay attention to what you're doing, clean the unit after you use it (and then put the film hanger back together immediately so that you don't lose any parts), and then store the tank in the original box, you won't lose any of the smaller parts.

-- Stuart Goldstein (satgre@worldnet.att.net), March 31, 1998.

I have a combi-T tank and find that, when developing small batches of sheet film (1 or 2 sheets), the plastic part on the bottom of the tank (the one with all the "teeth" supporting the film) tends to scrape off some of the emulsion. I find this unacceptable and am looking for another daylight processing film tank for 4x5.

-- Robert Ruderman (ruderman@seanet.com), July 27, 1998.

I have processed 2 sheets (up to 6 per batch) of film as well, but I didn't get the scratching on the negative. It sounds as if you either didn't place the top clip on the film holder or that you didn't lower it far enough to hold the film in place. So what happens during the processing, the negative slides up and down along the groove causing the scratches.

Another possible cause is the grooves on the film holder. Also make sure that the curved groves are on the INSIDE of the holder and not the outside (the straight groves should be on the outside). I was told that the straight grooves are for glass negatives. If the straight grooves are on the inside, you might get the same movement of the negative.

-- stuart goldstein (satgre@worldnet.att.net), July 27, 1998.

The worst problem with the Combi Tank was fill and drain times. As a daylight processor, it was disappointing. If you buy several (they sell bare tanks) and line them up with the necessary chemicals, they can be excellent dip and dunk tanks.

The only satisfactory daylight process I've found are the BTZS tubes, IMHO.


-- Mike Long (mlafly@aol.com), July 28, 1998.

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