Exposure or Developement

[Gerry Harrison]

Hello,

This question may seem weak ( dumb )..yet I will continue. I am in the process of trying different films..I am doing this in 120 format for convience & practicality. I set the setting as per instructions ( iso ) and develope the same ( time , mixture, temp and agitations ). Sometiimes the negs are thin and sometimes too dense..is there any way to tell if it is a wrong iso setting or too much or little developement. Of course I can adjust the exposure or developement for the final result..but is there a clue or observation to guide ones direction.

Thanks Gerry

[Capocheny]

Hello,

This question may seem weak ( dumb )..yet I will continue. I am in the process of trying different films..I am doing this in 120 format for convience & practicality. I set the setting as per instructions ( iso ) and develope the same ( time , mixture, temp and agitations ). Sometiimes the negs are thin and sometimes too dense..is there any way to tell if it is a wrong iso setting or too much or little developement. Of course I can adjust the exposure or developement for the final result..but is there a clue or observation to guide ones direction.

Thanks Gerry

Hi Gerry,

Have you done any tests to determine your films true EI?

What films are you using?

I've started shooting Tri-X at 160; HP5+ at 240, and FP4+ at 80 with much better results!

Cheers

[Andrew O'Neill]

If your negs are "thin" but the shadows look fine, then it's under development. If thin and nothing or very very little in the shadows of the negative, then you are looking at under exposure....or underexposure and under development combined.
If you haven't carried out your own personal EI tests, then you must do so. Then do your development tests.
I think Capocheny HP5+ EI is 250...He must be thinking about a 240mm lens...have fun tomorrow, Capo at that weird coffee shop...At least you won't notice the brown water!

[Ted Harris]

It could also have something to do with how you are metering your scenes/subjets. Can you give us some more detail of your workflow as you setup and prepare to expose the film.

[Ralph Barker]

Gerry - as Ted mentioned, providing more specific details about your testing procedure would be helpful. As I read your initial post, however, it sounds like you are using the same development time/temp/etc. for all of the films. If so, that may be the source of the variations you are seeing, as few films require the same level of development. The Massive Developer Chart is a good starting point for development times, but doesn't replace personal EI tests, of course.

http://www.digitaltruth.com/devchart.html

Also, you don't mention if you are using a rollfilm adapter on your LF camera, or a MF camera to do the tests. Either way, the consistency of your shutter(s) can also affect the real exposure the various films are getting.

You should also be aware of the fact that the formulations for the rollfilm versions of some films are sometimes different than the sheet film versions of the "same" film. Plus, your tank-development of rollfilms may produce different results than the procedure you use for sheet films. Thus, while testing with rollfilm may seem convenient and practical, applying the results to sheets may be difficult.

[neil poulsen]

In my experience, ASA's test out at about half of what the manufacturer recommended, or maybe not quite half. For example, shooting a mfg 400 ASA rated film at 200 is a pretty safe bet. Maybe just over 200. This would work for HP5, in my experience. Similarly, ASA 100 films test out at about ASA 60 for me. 50 works, though.

What are you looking for in a film? What makes a good film and what makes a bad film for you?

[robc]

What Ralph and Andrew said.

Also, many claim that personal Exposure Index (EI) turns out to be approx half manufacturers rated ISO. This needs to be taken in the context of your subject brightness range and the developer you are using.

What this means is that a typical landscape scene with sky and clouds will have a much greater brightness range than for example, a studio subject such as a portrait, which may have 2 or 3 stops less subject brightness range. As a result, the studio subject may need more development and using more development will increase your personal EI. Also some developers will have the effect of reducing your personal EI and some will increase it. Ilford Perceptol (largely metol based) giving the former and Ilford Microphen giving the latter.

This means that the generalisation that personal EI is usually half manufacturers rated ISO is not a valid generalisation and should only be given with typical subject brightness range and developer used before it becomes meaningful.

[steve simmons]

Here are my thoughts on film testing.

Using a different format than what you really want is silly. Your agitation will be different and the film may not be identical.

Asking people for their development time is silly. Their water suppy is different and its chemical content may interact with the film deveoper meaning their time has no relevence for someone located someplace else. And, no matter how carefully we describe our agitation pattern no one else can replicate it exactly.

You have to do your own testing with the proper film and the process you want to use. There is a simple foolproof method described in the Free Articles section of the view camera web site

www.viewcamera.com

If you are not willing to do this work just follow the mfg's recommendations and have a good time and don't worry about it.

steve simmons

PS

You also have to make sure you know how to use a light meter. If you are using your 35mm camera and then exposing with a different film camera you don't have a chance.

[Gerry Harrison]

Gentlemen,

First thanks for all the great input.I also have discovered that my question was way to vague..I'm sorry and will fill in some of the blanks.
I am trying different films ( 100 & 400 ) and in 120 size using a Hasselblad...I was aware that there is some difference in developement characteristics between MF & LF but obvoiusly this is not the way to go to determine MY personal end results. New to Large Format..so I'm a sponge at this point. I feel I was spoiled in MF..I shoot Agfa APX100 and 400..followed their instructions to the letter and was very pleased with the results. eg. Apx100 shot at 160....Rodinal 1:50 yada yada ApX400 shot at 360 Rodinal 1:50...super results...the APX100 is great but abit contrasty on bright days. This contrasty characteristic..started me on my different film journey.
So the same reasoning has followed for new films I'm trying..follow the manufactures directions for a start...I have found though with the new films I am trying it is not as easy as my love affair with Agfa film.
I would like to use the same developer for now to test new films..would D76 be a good choice or Rodinal ( some like it some don't )..most films I come across mention these somewhere or Ilford ID 11 which I understand is D76 like.
I also need accurate procedure for EI testing...would a studio setup be idea.
The films I have on hand are in 4x5 Agfa APX 100 ( I know are no longer available ) , Arista Edu Ultra 100 ( fomapan ) and Forte 400. I am going to be ordering from Freestyle some Kodak Tri X 400, Efke 100, Ilford HP5+ and some Chinese Era 100 on Ebay.

I really appreciate all the help you guys have given me and I have noticed my Canadian BC brothers are always first to bat also nice to see the Moderator and Steve Simmons making time too.

Gerry

[scott_6029]

Well, what are you priniting on? AZO, Silver, platinum, palladium....multi grade, what type of enlarger..i.e. density do you need? How do you meter? incident, spot, zones, ave.? How do you develop? tank, drum, tray? How do you agitate? what dilution developer do you use? With pyro, you sometimes increase box speed...not cut in half...

I think it was said best earlier...there are so many variables it's best to test on your own....In the long run you'll save money, time and effort...