Flickr Album: https://www.flickr.com/photos/metadi...57664271821431
I use 40 ml Rodoinol in 1 gallon tanks. 4 sheets 8x10 or 16 sheets 4x5 max at once. More or less 1/100. Not critical to me. There is an 1/4" pipe with holes on bottom of tank for agitation bubbles from compressed gas.
Look here in DIY and Web for N2 Gas Burst, Kodak Gaseous Burst system etc.
I think your suggestion of a chemistry change with time causing a density change and thus settling has merit; surely even with stand development, most of the development of highlights happens in the first few minutes. The absence of a heating control should reduce the chance of thermal convection.
Am I correct in my assumption that the main purpose of stand development is to increase edge accutance by local exhaustion of developer? It's been a long time...
Neil
p.s. the diametric opposite of this technique which I have recently adopted with some success (for my work; I'm not suggestion you should use it) is continuous agitation in a flat tank: for 4 off 5x4 sheets I'm using only 3cc of R09 made up to 150cc - which is a tiny amount of developer - and getting good full-range negatives. Previously I was using the same time and dilution, but with a litre of final solution in a tank, with five seconds agitation every minute - and getting thin negatives which wouldn't scan well.
Bingo!
I've seen many reports from stand development users in all formats that are consistent with concentration-driven flow across the film -- what you're seeing in the middle/late part of development in the light is very much that sort of thing. During the early part of development, the developer is gaining density, either due to dissolution of something from the film or due to oxidation of the developing agent, and the denser (partly exhausted or bromide restrained by bromide from the emulsion) solution is dropping to the bottom of the tank. This concentrates unaffected developer at the top edge of the film, and could, in extreme cases, lead to flow marks, smearing at edges that are nearly vertical and similar effects. By the time the solution color has evened out, this effect should be finished.
A confirmatory experiment would be to find something you could suspend in your working solution (plastic beads, gelatin bits or similar, preferably small and close to neutral buoyancy in the solution) and watch for movement of the particles, most likely downward along the film surface, while developing in the light.
If a contact print at arm's length is too small to see, you need a bigger camera. :D
Along the same line but a little off.Has anyone tried stand or semi-stand development on their prints? Just curious as I'm enjoying shooting paper negatives in-camera and wondering if the print paper and developers would behave in a similar fashion.Guess there's always someone out there with another idea,LOL!
Sometimes you can control the contrast of a print by diluting the developer further.
Try it.
From reading old books, this may give an idea of how some people gave control to the negative 80 years ago:
I have read about using three baths ( 4 baths, but we haven't Pinacryptol these days for calming the negative);
- Rodinal 1:20, but well used, will slow down the development of the highlights
- Rodinal fresh 1:20 for quick shadows and middletones
- Rodinal fresh 1:30 and of 25 degrees C, for finest shadow details.
- Switching between the trays, if needed...
For me, it is worth a try, of course with orthochromatic film,
Ritchie
Well, that's amazing.
I left the film in the jug for 24 hours.
The solution was still homogenous to my eye in terms of colour gradation down the jug.
But the film has that tell tale dark edge at the top!
So there are some options to consider now with regard to seeing if this effect can be eliminated.
1. Gentle regular inversion throughout the first x minutes of development
2. The question as to whether step 1 will cause over development throughout and thus demand a compensatory further dilution of R09 coupled with a longer overall stand time
3. Some other step(s) to consider?
As an aside, this Ted Forbes video: http://theartofphotography.tv/episod...arkroom-guide/
shows exactly what I'm talking about with medium format film. He offers no solution other than temperature control. But I know now that's not going to make any difference to this specific effect. Temperature control may make a differnce to the overall development of the bottom half of the film but will not eliminate the differential development top to bottom.
This may also go to explain why slower film or other film brand may not suffer this effect as much or at all. A slower film may be able to continue the same pace of development regardless of the local concentration of developer.
It's interesting that this confirms why a deeper volume of developer makes no difference. It's related to the size (height) of the film standing in the bath. The effect is directly proportional to the face of the film being developed, not any additional volume of developer above the top of the film.
The 6x7 film in the video above shows this even-ish band of over development at the top, whereas 35mm film tends to show drags from the film notches.
Alan
Flickr Album: https://www.flickr.com/photos/metadi...57664271821431
Well I'll be damned!
It works!
There is absolutely no sign (to my eye) of uneven development in the above raw scan.
The finished product is here: https://www.flickr.com/photos/metadi...7664271821431/
So this was stand developed in R09
8ml in 1000ml
Temperature controlled in a bath at 20C
Gentle inversions every 2 mins for first 8 inversions. Then again at 1hr. Total stand time 2hr.
Fix and Wash method did not change.
I'm a happy photog again.
Alan
Flickr Album: https://www.flickr.com/photos/metadi...57664271821431
ALANMCD writes: The recurrent theme is that the negative is darker along the top edge corresponding to the film position in the MOD54 and paterson tank.
There may be no issue with stand development in other tank arrangements. So if you do not use this method and have no problem, your claim to that is moot at this point.
The light edge is not associate with the presence or not of a highlight on the edge of the photo in question. It is undeniably related to whatever edge is UP in the tank. The top edge is over-developed.
-------------------------------
Submariners know you get motion near the surface while going deeper means smooth seas even in monsoon conditions.
Maybe developing flat in a tray with more chemistry will make a difference?
What you describe sounds a lot like 'edge density' from sheet film in too small a tray - where the edges get more wave action than the interior area of the negative.
Bookmarks