Determing normal development for film

All the techniques and equipment needed to develop film, create glass plates or print following traditional & alternative methods
Post Reply
User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Determing normal development for film

Post by Valerio Trigari » Mon Dec 05, 2011 2:37 pm Etc/GMT-1+01:00

Hi All,

I just wondered if you could explain the correct procedure for determining the correct normal development time, for a specific film/developer combination. Is the development time decided both on the density of the negative and the exposure of a test print? If so, how do you decide the correct exposure of the print, given a negative of the "correct" density? I read Ansel Adams' procedure, but I'm still confused... :?

Thanks for your help,

Val
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

gary mulder
Posts: 53
Joined: Thu Nov 26, 2009 6:33 pm Etc/GMT-1+01:00

Re: Determing normal development for film

Post by gary mulder » Mon Dec 05, 2011 5:53 pm Etc/GMT-1+01:00

There are a lot of ways leading to Rome. My current method is to put step wedge into my enlarger and determining the exposure that prints density 0,75 step on a grade 2 paper to a reflection density 0,75. Subsequently I print the negative I want to test with the same exposure. If the print has to much contrast shorten the dev. time. Not enough lengthen dev. time. If the print is to dark the film must have a lower asa setting. If to light, a higher asa.

User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Re: Determing normal development for film

Post by Valerio Trigari » Mon Dec 05, 2011 11:29 pm Etc/GMT-1+01:00

Thanks for your reply Gary. I suspected there was more than one way to do that. As soon as I will have a darkroom, I will do my own experiments, which is always a lot of fun! :)
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

zoikes
Posts: 32
Joined: Thu Feb 10, 2011 12:51 pm Etc/GMT-1+01:00
Location: Bristol

Re: Determing normal development for film

Post by zoikes » Tue Dec 06, 2011 8:46 am Etc/GMT-1+01:00

This must belong in the new wet processing forum!

I hadn't heard of that step wedge method...
I am fortunate (?) to have a transmission densitometer at work, so measure the densities. There are several ways of doing this (Adams, lambrecht...).

The most sensible way I have seen is Blakemore's method of taking pictures of a towel and working out times to give you texture at different zones. This isn't too technical and is tailored to your enlarger.

Ian

Paul Mitchell
Moderator
Posts: 491
Joined: Wed Dec 12, 2007 5:05 pm Etc/GMT-1+01:00
Location: Burnham, UK
Contact:

Re: Determing normal development for film

Post by Paul Mitchell » Tue Dec 06, 2011 1:37 pm Etc/GMT-1+01:00

zoikes wrote:This must belong in the new wet processing forum!Ian
Done!
When people ask what equipment I use - I tell them my eyes.

http://www.paulmitchellphotography.co.uk
http://www.arenaphotographers.com

gary mulder
Posts: 53
Joined: Thu Nov 26, 2009 6:33 pm Etc/GMT-1+01:00

Re: Determing normal development for film

Post by gary mulder » Tue Dec 06, 2011 3:26 pm Etc/GMT-1+01:00

There is a lot to find about the optimum development of the negative for further printing in the dark room. But not so much for scanning end post processing with PS. Is it possible to say how a negative should look like for scanning ? dmax - dmin ?

User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Re: Determing normal development for film

Post by Valerio Trigari » Wed Dec 07, 2011 12:15 am Etc/GMT-1+01:00

Paul Mitchell wrote:
zoikes wrote:This must belong in the new wet processing forum!Ian
Done!
Cheers Paul! I was going to send a message to you admins about this. :)
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Re: Determing normal development for film

Post by Valerio Trigari » Wed Dec 07, 2011 12:18 am Etc/GMT-1+01:00

gary mulder wrote:There is a lot to find about the optimum development of the negative for further printing in the dark room. But not so much for scanning end post processing with PS. Is it possible to say how a negative should look like for scanning ? dmax - dmin ?
I would love to do that, but I don't if there's a way to get actual density value from a scanner. Independently to what actual values of Dmin and Dmax are, the range is always normalised between 0 - 255 in a 8 bit grey scale. Does anyone know how to reverse that? Though I expect it to be scanner dependant.

Val
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

banana_legs
Posts: 46
Joined: Tue May 25, 2010 6:45 pm Etc/GMT-1+01:00
Location: North Wilts

Re: Determing normal development for film

Post by banana_legs » Wed Dec 07, 2011 9:55 pm Etc/GMT-1+01:00

Val,

If you have a step-wedge such as a Stouffer T2115 then you can scan that alongside the actual negative and then compare scanner readings in the negative to the scanner readings of the steps in the step wedge. I often plot a graph of the step values and their densities and then just use the graph to interpolate between the steps in the step wedge. If you have a reflective step-wedge, then you can do the same but for print density.

Best regards,

Evan
More mad ramblings at http://blog.concretebanana.co.uk

User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Re: Determing normal development for film

Post by Valerio Trigari » Thu Dec 08, 2011 4:27 pm Etc/GMT-1+01:00

Hi Evan,

thanks, that sounds like a very simple procedure. Where do I get a Stouffer step wedge from? I found their website, but I couldn't see it on any retailer in UK...

Cheers,

Val
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Re: Determing normal development for film

Post by Valerio Trigari » Thu Dec 08, 2011 4:51 pm Etc/GMT-1+01:00

Valerio Trigari wrote:Hi Evan,

thanks, that sounds like a very simple procedure. Where do I get a Stouffer step wedge from? I found their website, but I couldn't see it on any retailer in UK...

Cheers,

Val
I just ordered one from http://www.rhdesigns.co.uk. :)
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

banana_legs
Posts: 46
Joined: Tue May 25, 2010 6:45 pm Etc/GMT-1+01:00
Location: North Wilts

Re: Determing normal development for film

Post by banana_legs » Thu Dec 08, 2011 6:05 pm Etc/GMT-1+01:00

Val,

Yes I got my first step wedge from RH designs too, but recently purchased a 31 step transmissive and a 21 step reflective one directly from Stouffer in the US; I sent them an email to confirm the prices and then they can take the order by telephone.

Best regards,

Evan
More mad ramblings at http://blog.concretebanana.co.uk

User avatar
Valerio Trigari
Forum Hero
Posts: 164
Joined: Wed Aug 03, 2011 3:46 pm Etc/GMT-1+01:00
Location: Ipswich, Suffolk
Contact:

Re: Determing normal development for film

Post by Valerio Trigari » Wed Dec 14, 2011 11:11 pm Etc/GMT-1+01:00

I received the step wedge a couple of days ago. I didn't expect it to be so small, though it fits without any trouble in the film holder of my scanner. Hopefully it'll help me with my experiments.

Val
http://www.valeriotrigariphotography.com/

Proud owner of a Linhof Technikardan 45.

Post Reply