Thin b&w negs.

[alexecho]

I feel rather embarassed having to ask this, because a few years ago I knew the answer. I guess that working in a darkroom isn't like riding a bike - you do forget.

I've just developed three rolls of negatives, I used fresh chemicals for each (I did them days apart, and don't like to keep the stuff once mixed), was very fastidious about temperature and quantity of chemicals, followed the rules to the letter and all three rolls have come out very thin. Very little black on them at all.

After the first roll I thought it was the camera because it was the first time I'd used a fully manual camera, but I used a light meter and all three rolls are the same, from three different (old, manual) cameras.

I do remember that I either need to adjust the shutterspeed/apperture on the camera, or do something different in the processing.

I used to have this problem - I obviously miscalculate something though I've never established what, and I changed the developing time which cured the problem, but I just can't rememebr if I need to increase or decrease the time?

Also, (whilst I'm here making a fool of myself) to deveop really thin negs, am I right in thinking that I need to stop the enlarger down more than ususal, and boost the contrast with the magenta filter to avoid really grey looking prints?

I am planning on re-shooting the images that I think might be decent, but I want to see what I can make of the 'ruined' negs first. Help!

 

[JC1220]

Somewhat hard to say, possibly the meter, or the camera but you said you had tried 3 different cameras... Did you have the meter set to the correct film speed? If so, you could do a test of exposures, 1st at the correct reading , 2nd plus 2 stops, 3rd plus 4 stops. Or if you want a series of plus 1 stop exposures which might help you get your meter tuned in to your film and developing times. But check the meter for the correct film speed setting.

JC

 

[alexecho]

Thanks for that JC. I'm know the settings were correct, you've just made me double check, but I was right. One of the camera's has it's own light meter on the top of it, and this is giving almost exactly the same readings as the other light meter, so it's not that.

I might try going up a stop or two on the manual camera, but I've shot with a fully automatic camera in the past (years ago) and had the same thin negs then I've processed them myself.

I'm positive it's my developing times that are out... Or my temps. If I developed my films a minute longer or increased my development temp by a degree, would that have the desired effect?

 

[JC1220]

What film, developer and time are you using now?

But, to answer your question, yes if you increase time it should help some, but if they are under exposed, you can only get so much from plus development.

 

[Hertz van Rental]

Have a look at the negs.
Can you see the edge markings down the rebates?
If they are very thin like the negs then you have a processing problem.
If they are quite dark - or darker than the darkest part of the neg - then you have an exposure problem.
All good quality films have edge markings - giving frame count and film type info - that are printed on with a standard exposure. Whenever you have problems like this they are the first thing to look at so you can determine the general cause.

 

[alexecho]

JC1220 I'm using Jessops own film, developer and fixer. I know that will mean nothing to Americans! It's actually what I used when I was doing photography in college, so I know the quality is OK. Not really brilliant but OK. It's just cheap stuff and I was only testing the old cameras out. The development time is 7 minutes at 20c, as listed both on the film box and developer bottle (and rattling around somewhere in the dark recesses of my mind too).
As I said in my last post I once had this same problem with a fully automatic camera - I'm sure those settings wern't out... I know changing development time can only adjust so much, but I am confident in my own mind that it is the development that is wrong.

Hertz, I knew I forgot to mention something! (Knew I'd forgotten more than I'd ever learnt.) The edge markings are there, but thinner than I would expect them to be, rather like the images themselves...

Thanks for the help guys.

 

[Hertz van Rental]

I believe that Jessops film used to be made by Orwo in E Europe. No idea who makes it for them now.
It's cheap but dependable.
Sounds to me like a processing problem.
If the dev is fresh, it's properly diluted and you have it to temperature* then it is most likely agitation that is at fault. Should agitate 5 secs every 30 secs.

*If the ambient temperature is more than a few degrees below 20C then the developer will lose heat, dropping it's temp and slowing development. You'd be suprised the difference a few degrees can make.

 

[alexecho]

The temperature was reading at 20 degrees just as the water came out of the tap which surprised me a little bit, but it was a warm day, so I thought it must be accurate. Maybe my thermomitor is out. I'll just add 30 seconds to the processing time and hope that improves things...