how to develop underexposed negs for better detailles

[AndreiF]

Hello! By mistake I underexposed some 4x5 foma (100 iso) negatives with 1-2 steps (depending on the case) Instead of 2 seconds for example I set half of the second on the dial(also a "2" number, that why the confusion, I was sleepy and in a hurry But I rated the film at 50 iso, so in theory it should be just one step. Are studio photos (portraits) with a dark background.

I would prefer to use hc 110 or rodinal (I can't buy other stuff) What do you recommend to adjust in this case? It is possible to compensate in some way?

Thank you very much!

 

[Gerald C Koch]

A one stop underexposure should be within the latitude of most B&W films. However be prepared to print on grade 3 paper. Develop the film normally in HC-110. Rodinal causes a further speed loss and in this case would not be recommended. Trying to "correct" the under-exposure by increasing the development time will result in an increase in contrast without any real increase in detail. The amount of detail in an image is determined by exposure and not development.

 

[marciofs]

I guess if you develop in a very diluted solution such as 1+75 or 1+100 in Rodinal, it will deliver a less contrasty negative where you culd possibly get more details from shadows.

An other safe option is semi stand development. 1 stop is almost nothing for most films anyway.

 

[AndreiF]

Thank you for the advice, to both of you. I think I will try the hc 110 suggestion, with H dilution. Even if are 2 stops underexposed it is ok with this film?
I can't do stand development as are plan films that i will develop in trays, will be to much time in my tiny, hot bathroom in the dark And actually I think that now I have normal to low contrast, with stand I will get even less contrast from what I recon..

 

[ic-racer]

ISO, of course eliminated the safety factor. So one stop under is ruined.

 

[RalphLambrecht]

Hello! By mistake I underexposed some 4x5 foma (100 iso) negatives with 1-2 steps (depending on the case) Instead of 2 seconds for example I set half of the second on the dial(also a "2" number, that why the confusion, I was sleepy and in a hurry But I rated the film at 50 iso, so in theory it should be just one step. Are studio photos (portraits) with a dark background.

I would prefer to use hc 110 or rodinal (I can't buy other stuff) What do you recommend to adjust in this case? It is possible to compensate in some way?

Thank you very much!

As Gerald already said, one cannot compensate with overdevelopment for under exposure.That would just raise the contrast and mke matters worse.You are better off to devevelop as recommended for this film and speed in HC110 and correct the rest with VC paper and D&B.start with Grade 3 and take it from there.Good luck

 

[RobC]

If you use HC110 do NOT use highly dilute because that will lose you more film speed. 1:31 or 1:15 would be better still.

HC110 has a long shallow toe which is made much worse by overly diluting it. Don't get me wrong, its a good dev for 4x5 film but only if you shoot at low EI and you have gone the other way.

Diluting most developers from stock will lose speed and put a longer shallower toe in the curve which is the last thing you want if you are trying to retrieve shadow detail from undersxposed negatives.

However, your best bet would be to use a speed increasing developer such as Ilford microphen. But you would probably need to do some dev tests to find out whats optimal with that film dev combo before committing your negs to it. And don't dilute it from stock.

 

[pentaxuser]

Diluting most developers from stock will lose speed/QUOTE]

Are there developers to which this doesn't apply such as Perceptol where a dilution of 1+3 seems to increase speed. Most responders here seem to state the opposite i.e. one of the consequences of dilution is to slightly increase speed

Is there a common link in terms of ingredients that needs to be looked for in terms of increasing/decreasing speed?

Thanks

pentaxuser

 

[Huub]

Try something like XTOL or Microphen as these developers make good use of the nominal film speed. Both Perceptol and Rodinal will make you loose at least a third a stop of speed.

 

[RobC]

Diluting most developers from stock will lose speed

Are there developers to which this doesn't apply such as Perceptol where a dilution of 1+3 seems to increase speed. Most responders here seem to state the opposite i.e. one of the consequences of dilution is to slightly increase speed

Is there a common link in terms of ingredients that needs to be looked for in terms of increasing/decreasing speed?

Thanks

pentaxuser

Diluting does NOT increase effective film speed. It increases acutance which makes it look sharper.

In this case the film is under exposed and diluting WILL make the toe much shallower. This is normally dealt with by reducing EI to give extra exposure which shifts the exposure up the curve and off the long/shallow toe. But the opposite is true in this case. The exposure has been shifted down the curve and possibly right off the bottom of it. Diluting developer WILL NOT help retreive the lowest values in that case, it will do the opposite.

Perceptol is just the same.

Phenidone seems to provide a speed increase of 1/3 to 1 stop of speed when used in correct formulation which I don't have a list of. Others here will know better than me.

I have never tested a film where I found the toe became shorter when the dev is diluted past stock but I haven't tested many compared to the possible combinations that are to be had if you want to try them.

If the argument is that the increased acutance makes it easier to pick out shadow detail then theoretically that may be true. The problem is that because the toe has been made shallower it will counter act any perceived extra detail right at the bottom end of the toe. So ask those who say diluting developer increases speed exactly how far down the curve it does that because I would strongly doubt that any of them will tell you it does it AT below 0.1 density and that is precisely where we are trying to retrieve information from in this case.

 

[pentaxuser]

Thanks for the explanation, RobC. My post was based on what I had seen or maybe had interpreted (rightly or wrongly) from posts here on APUG and also on what I had seen on the Ilford site about Perceptol, namely that Ilford gives times for HP5+ and I think D400 which list various speeds at stock and dilutions of 1+1 and 1+3. In both cases it lists times and speed at stock then higher speeds at 1+1 and 1+3 where there are no times at stock albeit all speeds are less than box speed.

It would look as if we or maybe it is just me, should avoid any inference that dilution in speed reducing developers is a way of increasing speed or more accurately reducing the reduction in speed compared to stock.

If I use Perceptol at stock and this reduces the film speed to say 200/250 from 400 then a dilution of 1+1 or 1+3 will achieve nothing in terms of a less reduction in speed.

So yes this is a kind of negative way of looking at film speed increases in that I had thought that dilution simply reduced the drop in speed but in fact does not

pentaxuser

 

[AndreiF]

Thank you RobC for the advice and very good info! Unfortunately I already developed when you left the comments. But it is good to know in the future! The negs got well, developed in HC 110 (9 min), dilution H with constant tray agitation.

 

[ic-racer]

Increasing development allows printing on conventional grade papers without the under-exposed negatives looking flat or gray. Unexposed shadow details are always unexposed shadows.