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  #1  
Old 16th July 2010, 09:23 PM
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Default Increasing Negative Contrast

Hi Les

What methods can I use to increase contrast in my negatives?
I currently use Fotospeed FD10 developer for 8-10 minutes (times taken from the chart supplied with the developer) agitating for 15-20 seconds every minute, Fotospeed SB40 Stop Bath for 1 minute constant agitation, Fotospeed FX20 Rapid Fixer for 2 minutes agitating 15-20 seconds every minute and finally a 10 minute gentle rinse of constantly flowing cold water using a minute amount of washing up liquid as a wetting agent to finish off.
I use all the chemicals at 20 degrees as I stand the bottles in a monitored water bath.
I have even tried a longer than recommended developing time to no avail.
I have recently used Ilford Delta 400 Pro and HP5 but for some reason the negatives on both these film types are lacking in contrast almost to the point that a grade 5 print looks about right.
Printing onto Ilford Multigrade 8x10 Pearl paper.
I have checked my cameras exposure metering with a seperate light meter and it is accurate, so I am satisfied it must be something I am doing during the processing stage.
Any help would be much appreciated.

Thanks
Andy
 
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  #2  
Old 16th July 2010, 10:32 PM
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Hi Andy

First of all do you meter the contrast range of the subject?
How do you meter the subject? The accuracy of the meter is of no consequence if you are not metering the subject properly. Can you post that information here for it may provide us with part of the answer.

Increasing contrast by development can be achieved in several ways.

1) An increase of 25 to 30% developing time will give you about 1 stop increase in contrast. Be careful not to increase the time by too much as this will increase the grain. I usually only increase development by up to 60% at most.

2) Reduce your initial exposure and increase development as suggested above. This will make the shadows darker and the highlights brighter resulting in an increase in print contrast.

3) Use a different developer, for example Rodinal is a high accutance developer which will increase contrast.

4) You mention that you are using a 400 ISO film. This happens to be lower in contrast that medium or slow films so try FP4+ or Pan F.

5) When printing experiment with different papers for there is quite a difference in the contrast of say, Ilford Warmtone, a slow high contrast paper, and Ilford Multigrade IV, which is a faster but lower contrast paper.

I'd also suggest that you try using a gloss paper preferably fibre based which will also provide a higher contrast than a Pearl RC paper.

Please get back to me with the information I asked for and we'll sort out this problem quite quickly.
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Old 17th July 2010, 08:17 AM
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Hi Les

I use a Bronica ETRSi which is fitted with an AEII Metering Prism. The prism is an average meter.
The handheld meter which I used would have also metered on an average rather than spot metering.
I had considered the metering as a problem but when the readings from two meters were identical I automatically assumed it must be something else I was doing wrong.

Thanks
Andy
  #4  
Old 17th July 2010, 06:27 PM
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[QUOTE=HopALong;33212]Hi Les

I use a Bronica ETRSi which is fitted with an AEII Metering Prism. The prism is an average meter.
The handheld meter which I used would have also metered on an average rather than spot metering.
I had considered the metering as a problem but when the readings from two meters were identical I automatically assumed it must be something else I was doing wrong.

Hi Andy

Thanks for the information re metering. The description of your method of metering is, in my opinion, a large part of the reason for lack of contrast in your negatives. The fact that your meters both give the same reading is really not important. However what is important is where you take the reading from. You tell me that you use an average metering setting rather than spot matering and this I feel is your problem.

What an average reading does is to average out a number of pre set points to produce a reading of sorts but it is not specific for either shadows or highlights and therein lies the root of your problem.

I would suggest that you consider learning a little about the Zone System and feel that to do so would help you unfderstand more about the importance of correct metering and how it will ensure that you produce a negative that holds all the necessary information to make a print with the tonality that you saw when you made the exposure.

I'll also explain here how all camera meters work which will also help you along the way. It is generally accepted that meters are set to see all tones as mid 18% grey although there are photographers around who dispute that. As an example as to how a meter sees tones; if you photograph three cards, black, mid grey and white using the readings shown by any meter then make a print using standard printing time, all prints will be mid grey because that's how the meter sees them and provides an exposure reading that will produce a grey print.

To produce a black, grey and white image in print you need to interpret the readings given by the meter at the time you made the exposure as follows; Expose the grey card exactly as the meter indicates, for the black card under expose the reading indicated by the meter by 2 stops and for the white card over expose by 2 or even 3 stops. This method is standard Zone System practice and will produce negatives that show the contrast that is inherent in the subject you are photographing.

To transpose the above into making photographs in the landscape (who in his or her right mind wants to photograph black white and grey cards) Take you spot meter reading from the darkest shadow and under expose by two stops from what the meter says. I would always suggest you EXPOSE for the shadows for not to do so will produce a negative with little or no shadow information. Having said that there are times when you want a total black shadow in a very graphic image, this would be the only time I would not expose for the shadow.

Take a second reading from the brightest tone in the scene, beware here don't meter the sun or sunlit highlights in water, and calculate how many stops of contrast you are photographing. This is quite simple, by leaving the fstop as set for the shadow you will have to adjust the shutter speed to a faster setting to deal with the bright highlight. Count the number of stops between the two respective shutter speeds to arrive at the number of stops of contrast. This will tell you how to develop the film. Three stops to five stops of contrast is normal development, below three is plus development and more than five is minus development. You will recall that I suggested that 25 to 30% increase or reduction in development represents 1 stop of contrast so if you apply that to the plus and minus exposure you will have full control over contrast.

I'm sorry that what I have just written sounds quite complex but you have to work at it to master it. I have never forgotten my own struggle to understand it some 35 years ago. Practice and don't be afraid to make mistakes for you will learn from them and once you understand the principles you will always be very confident about dealing with exposing negatives in very difficult conditions and just as importantly making prints from those negatives will be relatively simple.

If you need further help please make a post and we'll continue until you are happy.

Best wishes

Les
  #5  
Old 17th July 2010, 07:21 PM
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Thankyou so much Les for your time and help.
Although complex I understand what you are saying.
I shall look into the Zone System in a bit more depth and then put it into practice.
No doubt there will be spectacular failures along the way, but where's the fun in getting it right first time.

Just one last question.
Which meter would you suggest purchasing/using as the two I have are not spot meters?

Thanks once again.
Andy
 
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