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RSalles
3-Aug-2015, 22:14
Hello,

I have developed some 4x5 negatives the last week-end, and unfortunately three of them had some uneven developed areas at open ski.
Film: Shanghai GP3, Yankee agitank, HC-110 dil H (1+63).
As my workflow has always been nearby the same for the last years regarding agitation with 4x5 film, I would ask what else can contribute to this unevenness in the negatives, restricted to the open sky area only:

https://farm1.staticflickr.com/561/20089862539_3eb6dcc126_c.jpg (https://flic.kr/p/wBgNdk)_MG_7743 - _MG_7748 (https://flic.kr/p/wBgNdk) by Renato Salles (https://www.flickr.com/photos/sallesrenato/), no Flickr


https://farm1.staticflickr.com/512/20250244936_9f33708ef5_c.jpg (https://flic.kr/p/wRrNj5)_MG_7736 - _MG_7739 (https://flic.kr/p/wRrNj5) by Renato Salles (https://www.flickr.com/photos/sallesrenato/), no Flickr

Cheers,

Renato

Randy
4-Aug-2015, 04:59
Any uneven development is not restricted to open sky only, it is just much more visible in the sky because there is no place for it to hide - no roads, rocks, trees, lakes, cows, etc. On my monitor I can not really make out unevenness on your samples, so I can't really offer a cause or prescribe a corrective measure, even though at present, I am the master of uneven development, especially with my 8X10 X-ray negs. I have been fighting with it for months now, trying different methods to correct.
The only thing I can suggest is to shoot a few test shots of scenes with mostly sky, or at least 1/2 the image being clear sky - try different agitation methods and frequencies to see what results in the smoothest sky's. For my 4X5 films, I have always processed in trays and have never gotten uneven development.

tuco
4-Aug-2015, 06:10
I see the density streaks just fine. Most likely you need to either increase your agitation or make the one you use more vigorous. Gently moving your sheets in a tray can yield laminar flow across the boundary layer on the sheet. The developer is working in this very thin layer against the film and gets exhausted quickly. So we agitate to replenish it. But if the fluid flow is laminar, it will "slide" over that thin boundary layer leaving the some of the exhausted developer in place.

Ken Lee
4-Aug-2015, 07:16
Another consideration: colder developer (or weaker developer) and longer development time. Use ice cubes if necessary to lower the temperature of the developer.

Jim Noel
4-Aug-2015, 08:56
When I was teaching at the college the most common reason for such streaks was overly gentle agitation. If developing in a tray, my favorite method, agitate by lifting 3 corners just to the point of sloshing the developer out of the tray.
If we think of the tray corners as 1,2 3 and 4, for the first agitation cycle lift corners 1, 2 and 3. For the second cycle corners 2,3 and 4, third cycle 3, 4, and 1, etc.
When I develop 4x5 film a cycle takes about 4 seconds. For 8x10 it takes 5-6 seconds and for 7x17 - 6-7 seconds.
Be sure to use a tray one size larger than the film.

Jerry Bodine
4-Aug-2015, 13:22
Another consideration: colder developer (or weaker developer) and longer development time...


When I was teaching at the college the most common reason for such streaks was overly gentle agitation...

FWIW, when I tested HP5+ / HC-110 for EI and contraction development down to N-5, I heeded AA's suggestion to ensure even development. I came up with EI=200, then for N-5 used 1+123 @ 20C, making two identically exposed negatives - one with 31-step wedge (in camera) and another w/o wedge to check for uniform density. Since total dev time would be quite long, I carefully placed the films in a 4-up hanger to keep them from floating in the 11x14 tray. After a 2-min water pre-soak (very controversial subject) with moderate agitation, I placed the hanger in the diluted dev (25ml concentrate + 3075 ml water) and agitated by slowly raising/lowering it while keeping it submerged (to prevent foaming and surge marks from dev squirting through hanger's edge holes). Total dev time = 20 minutes.

1st test: Agitate 1st minute, then 15 sec every 3 min gave even development.
2nd test: Agitate 1st minute, then 15 sec every 6 min gave uneven development.
3rd test: Agitate 1st minute, then 15 sec every 5 min gave even development.

Plotting the data showed that an additional stop of exposure was needed (beyond the EI 200 reading) to preserve shadow details for N-5 development. While this testing can be diagnosed as overly analytical, I found it to be an extremely educational process to go through at least once. It was a bit expensive too - I've only presented the final results here rather than every step of the way.

Jim Noel
4-Aug-2015, 15:19
The testing may have been "overly analytical", but you appear to have solved your problem.

axs810
4-Aug-2015, 15:26
Do you pre-soak before development? Maybe that would help

LabRat
4-Aug-2015, 16:48
Also, it might be an issue with the film stock... Shanghai often has quality issues...

Steve K

RSalles
4-Aug-2015, 19:07
Any uneven development is not restricted to open sky only, it is just much more visible in the sky because there is no place for it to hide - no roads, rocks, trees, lakes, cows, etc. On my monitor I can not really make out unevenness on your samples, so I can't really offer a cause or prescribe a corrective measure, even though at present, I am the master of uneven development, especially with my 8X10 X-ray negs. I have been fighting with it for months now, trying different methods to correct.
The only thing I can suggest is to shoot a few test shots of scenes with mostly sky, or at least 1/2 the image being clear sky - try different agitation methods and frequencies to see what results in the smoothest sky's. For my 4X5 films, I have always processed in trays and have never gotten uneven development.

Randy,

Saw that also, I sort of photoshoped a the sky area to try to "hyde" a bit the strikes but it didn't happen. I'll do some test shots to try to nail the problem - maybe lack of agitation, but I tough i had the same amount of it, let's see, thanks,


I see the density streaks just fine. Most likely you need to either increase your agitation or make the one you use more vigorous. Gently moving your sheets in a tray can yield laminar flow across the boundary layer on the sheet. The developer is working in this very thin layer against the film and gets exhausted quickly. So we agitate to replenish it. But if the fluid flow is laminar, it will "slide" over that thin boundary layer leaving the some of the exhausted developer in place.
Tuco, that's what I had in mind when looking at the negatives in the light table, maybe I had filled too much the tank and avoided to spill some developer, and agitated less then usual.


Another consideration: colder developer (or weaker developer) and longer development time. Use ice cubes if necessary to lower the temperature of the developer.
Ken, thanks, I used 15 minutes at 20ºC which is enough time IMHO, maybe I have to be a bit more aggressive in the agitation, I'll see,


Do you pre-soak before development? Maybe that would help
Yes axs810, pre-soaked for 2 min at 20ºC


Also, it might be an issue with the film stock... Shanghai often has quality issues...



Forgot to mention, 2 sheets of Shanghai and 1 sheet of Foma 100...

I'll give another try and see what happens, that's f* annoying, maybe it's time to test BTZS, dunno... For tray... fear to be 20 minutes in the dark and dye bored, maybe not,

But thanks guys, your help have been very much appreciated,

Cheers,

Renato

Old-N-Feeble
4-Aug-2015, 19:16
Are you absolutely positively certain the films were completely fixed?

RSalles
4-Aug-2015, 20:20
Yes, double fixed, BTW,

Thanks,

Renato

Jerry Bodine
4-Aug-2015, 22:12
...maybe it's time to test BTZS, dunno... For tray... fear to be 20 minutes in the dark and dye bored, maybe not...

The biggest hazard is not "death by darkness", but rather letting the mind drift and losing track of what you're doing when testing non-image negatives. Think how much more exciting it is when awaiting IMAGE results!

LabRat
5-Aug-2015, 00:57
I don't mind sitting in total darkness... I figure that my eyes see an overload of information (that I want to see or NOT)... Gives them a rest... And it connects me with my other senses (and stills my mind) in a different way... I think of a dark cycle as a form of rest and meditation... And it allows me to "place" where my hands are without visual cues, and develop a "sense memory"...

But back to agitation, non-inverting small sheet film tanks are dicey to get even developed film (on a good day)... It can be done, but I remember that some odd sheets would have some issue sometimes... High key areas were always hard to get even... Or some inner or outer sheet in the stack would have a different agitation pattern... More diluted developers (that didn't produce larger/denser "clouds" around high value areas) helped...

I have rack (dip & dunk) hangers that work well for multiples, but I tend to use a oversize tray for film, as my newer direction with LF is one shot/one sheet, and guide that single image through the process... (Something Zen-like about that...)

Steve K

jumanji
5-Aug-2015, 01:35
Could be due to insufficient minimum stock solution per sheet. Next time you may try more stock solution and agitate a bit more vigorously.

tuco
5-Aug-2015, 11:32
But back to agitation, non-inverting small sheet film tanks are dicey to get even developed film (on a good day)...


I develop my 4x5 sheet in a daylight tank with a machine to agitate it just like my 120 roll film. No problems with uneven development. In fact, I get better results than tray developing. Of course mileage varies for each individual in that department. I made that machine because I could not stand sitting in the dark doing tray developing.

Jerry Bodine
5-Aug-2015, 13:36
...I could not stand sitting in the dark doing tray developing.

Nor could I, a choice would have to be made - stand or sit. :)

RSalles
5-Aug-2015, 17:06
Nor could I, a choice would have to be made - stand or sit. :)

:D X2!

Cheers,

Renato

AtlantaTerry
6-Aug-2015, 00:59
Yankee agitank

Renato,

You just answered your own question.

To resolve your problem you will only need to throw the Yankee tank into your recycling bin. It is an awful piece of equipment which has a horrible reputation for exactly the problems that you are having.

My suggestion is to watch for people who no longer want their 4x5" stainless steel racks such as Kodak's #4A. Buy as many as you can find because as time goes by they will become more and more scarce since they are no longer being made.

Once you have some stainless steel racks you can look for something to use to hold your developing chemistry. I found some 106 ounce tubs at my local discount store for US $1 each. (Dollar Tree Stores) I find I can develop up to a dozen sheets of film at a time in a tub.

To prevent cross-contamination I marked each tub and lid for what they should hold: Wash, Developer, Stop Bath, Fixer, Hypo Eliminator and PhotoFlo.

These days I no longer have a "real" darkroom so use my bathroom sink. I line up the marked tubs then put about 105 ounces of water or chemistry into each. Then I place the lids on top. When I'm ready, I make sure the top of the counter has no spilled liquids on it that would contaminate my 4x5" sheet film holders.

I place the number of film racks I will want to use into an empty tub and have a second empty tub waiting where I will place each loaded rack.

After I empty both sides of each sheet film holder, I place it into a drawer under the counter.

When all of the racks are full I wrap a very large rubber band around them about half way up. I found this to be useful otherwise when I pick up the racks in the dark they tend to fan out then when I'm trying to insert them into the tubs it is a struggle in the dark. The large rubber band prevents this. I found the rubber band in a store where it is sold to hold plastic trash bags in place in trash bins. I remove it from the racks after developing is finished and before the racks go into the stop bath. Then I wash it well while the sheets of film are fixing and washing.

I pre-wash for about 5 minutes to remove most of the anti-halation dye this also helps eliminate any air bubbles between the sheets of film and racks. Then I develop in HC-110 dilution "H". About every 45 seconds, I lift the group of racks and tilt it to one side. Then 45 seconds later, I lift them and tip them to the other side. I repeat this until the developing time has completed. Then I place the racks into a very weak bath of water + distilled vinegar to both stop the developing and remove some of the work the fixer will have to do thereby giving it a longer working life. Wash, hypo eliminator, wash again then a PhotoFlo bath. Hang to dry over my bathtub. Leave the room for a couple hours.

With this process, I get no streaks or uneven areas in the sky, walls, etc.

Here are some Android cell phone snapshots of my bathroom darkroom:
137970 137971
Notice I tied simple knots in the poly rope every couple inches. These prevent the sheet film racks from sliding down the catenary which would run the danger of the wet film possibly being damaged while drying. Without the knots, all one would have is friction and hope.

If you are lucky you might find a used HP Combi set. I have one of those as well and use it for short runs. These are no longer made but parts are available. Watch eBay or Craigslist for a set which is at least 3 items: tank, adjustable sheet film rack and a film insertion guide. There were other accessories which are less important such as funnels.

tuco
6-Aug-2015, 05:55
The HP Combi Plan tank does okay. It could use a little improvement with a larger diameter fill/drain spouts, however. But otherwise it will get the job done. I use it for my development.

https://farm4.staticflickr.com/3341/3227435413_ea290b9719_z.jpg?zz=1 (https://flic.kr/p/5Vcs7a)

RSalles
6-Aug-2015, 09:29
Terry,

Yes, a Combi it's an option also, I was somehow surprised 'cause I use the Yankee there is 3 years already and never came across this type of problem before, rak dev would be an option too,

Tuco,

As I'm aware of the Combi tank capabilities, I could not take off my eyes from the Ag-O-Matic you've built. Saw the video also, just amazing,

Cheers,

Renato

tuco
6-Aug-2015, 10:40
Tuco, As I'm aware of the Combi tank capabilities, I could not take off my eyes from the Ag-O-Matic you've built. Saw the video also, just amazing,
Cheers...

Thanks. Yeah, my choice in tanks was decisively influenced by what was easily adaptable to Ag-O-Matic.

Peter York
6-Aug-2015, 12:30
Atlantaterry expressed my sentiments perfectly. The Yankee tank works well as a drying rack but not much else. When I obtained a very good scanner (Screen Cezanne) I noticed uneven development with virtually all negatives, to varying degrees, with my Yankee Tank. I switched to a unidrum (see the article on the LF Home Page) and the problem went away.

gsinico
11-Aug-2015, 00:36
Try another sistem: Jobo. Find out a tank whit reel, it holds 6 sheets of 4x5' and try rotary process. You can do it by placing the tank floating in the sink. Or you find some device joust to roll, I have a CPE Jobo. Here in Europe are very popular , I can do E6 and all kind of BN.

RSalles
12-Aug-2015, 21:59
Just an update for those who helped, I've made myself a number of BTZS-like tubes, developed 2 test negatives and all came fine till now - apart some light scratches on the acetate film side due probably by the raw material of the inner side of the tubes. But at least one walk with serious intentions in the landscape department with that great skyscapes that I love will confirm the success or not of this workflow - as soon as I have some samples it comes to this thread,

Thanks,

Renato