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RodinalDuchamp
18-Apr-2015, 12:24
This will be a rather lengthy post so thank you to those who read it through.

I started using the 4x5 nearly 3 or 4 months ago. I know I know a veritable lifetime.

During this time I have experimented with several exposure metering techniques and combinations. However I have still not produced adequate negatives.

My negatives are thin even though I believe I am exposing adequately.

Here is a run down of my setup and an exposure example:

Tri-x 320 @ 200 developed 8 minutes in trays with D76

One of the more successful exposures I have attained was during morning light 9-10 am. The exposure was F32 1/4 sec @ 200

The negatives I am getting have been looked at by a couple of older wiser and much more informed people than myself and both have concluded they need more exposure to accentuate the tonal range/separation.

I have tried using a gray card, I have tried placing shadows in zone 3, I have tried metering for the shadows that is taking a reading at the darkest shadow and exposing for that as zone 5.

I'm determined not to give up but I need some help. Where might I be going wrong? Unfortunately I don't have a scanner to present my prints which are also sub par but more importantly the thin negatives.

Guys I'm ready to take any advice at this point. Too add one more piece of information, None of my negatives are overexposed, I'm not coming any where near overexposure.

Randy Moe
18-Apr-2015, 12:34
Check your shutter speeds. Buy the shutter speed app.

However most shutters run slow, so it must be something else.

So double and triple the exposure times. Do a test with dark slide being moved an inch every exposure, write it all down.

Jac@stafford.net
18-Apr-2015, 12:40
We do not know what lens and shutter you are using.
I have had a couple of lenses put into a shutter with
incorrect aperture markings. Perhaps your issue is the same.
.

Jon Shiu
18-Apr-2015, 12:45
Also, check your meter against other meters. Check your development. Make sure your thermometer is accurate.

Jon

RodinalDuchamp
18-Apr-2015, 12:49
We do not know what lens and shutter you are using.
I have had a couple of lenses put into a shutter with
incorrect aperture markings. Perhaps your issue is the same.
.
I can confidently state its probably not my lens or shutter as this has been consistent across all of my lens/shutter combos.

RodinalDuchamp
18-Apr-2015, 12:49
Check your shutter speeds. Buy the shutter speed app.

However most shutters run slow, so it must be something else.

So double and triple the exposure times. Do a test with dark slide being moved an inch every exposure, write it all down.
That has never occurred to me. I'm going to start by making that test on a single sheet.

Michael E
18-Apr-2015, 13:00
Expose for the shadows, develop for the highlights. If your shadows are too thin, you need more exposure, if your highlights are less than deep black (in the negative), you need more time in the developer. I usually rate my 100 speed (b/w) film at 25 to get what I want.

Ken Lee
18-Apr-2015, 13:36
All shadows are not created equal.

We may not want to place a white object on Zone III just because it's in the shade. We may not want to place a black object on Zone III just because its in the shade.

Why not find a test subject in flat light, where there are no shadows at all ? In flat lighting, you can safely place a middle gray item on middle gray.

No system is perfect or best. Each can be misused or misunderstood.

bob carnie
18-Apr-2015, 13:42
Switch from Spot Metering to Incident.. you may be over thinking your exposures a common problem

Also I have been making negs for a long while and I only use the sunny f 16 .. pretty dam simple and very reliable.

I will refer to a incident meter indoors and with hot lights.

expose for your open shadows if you are working outside.

jnanian
18-Apr-2015, 13:49
Switch from Spot Metering to Incident.. you may be over thinking your exposures a common problem

Also I have been making negs for a long while and I only use the sunny f 16 .. pretty dam simple and very reliable.

I will refer to a incident meter indoors and with hot lights.

expose for your open shadows if you are working outside.


+1

Merg Ross
18-Apr-2015, 13:51
I don't believe that you mentioned bellows extension. If any, have you compensated accordingly with an exposure increase?

Randy Moe
18-Apr-2015, 14:07
Switch from Spot Metering to Incident.. you may be over thinking your exposures a common problem

Also I have been making negs for a long while and I only use the sunny f 16 .. pretty dam simple and very reliable.

I will refer to a incident meter indoors and with hot lights.

expose for your open shadows if you are working outside.

+1 on Sunny 16. The exposure should make sense without meters, of course as Bob says, outside only.

I shot S-16 all my life. I bet a lot of us did, as 35mm came with those instructions printed inside the box. Never had a meter or camera with a meter for 40 years.

But I still compose lousy images. :)

Randy Moe
18-Apr-2015, 14:17
I also suggest to do what i often do.

Shoot a roll of 35mm using Sunny 16 in different light and aperture. Don't worry about composition or content, just check your Sunny 16 exposure judgement.

If you can shoot good exposures on 35 mm you can do LF the same exact way.

Richard Wasserman
18-Apr-2015, 14:23
I've found Sunny 11 to work better than 16....

I also suggest an incident meter, which you still need to learn how to use.

Bill Burk
18-Apr-2015, 15:06
RodinalDuchamp,

D-76 straight, or diluted 1:1? At 1:1 my standard time is around 13 minutes, several sheets in trays with constant shuffling.

My first thought is maybe you need longer time in the developer.

RodinalDuchamp
18-Apr-2015, 15:16
I have tried incident metering as well. I have even metered incident in shadow and in brighter areas and tried averaging them.

RodinalDuchamp
18-Apr-2015, 15:21
RodinalDuchamp,

D-76 straight, or diluted 1:1? At 1:1 my standard time is around 13 minutes, several sheets in trays with constant shuffling.

My first thought is maybe you need longer time in the developer.
D76 1:1 sorry for omitting that. I have a sloshed and use constant agitation. I thought it might be underdevelopment because I have tried every kind of exposure metering and I have even attempted overexposure and none of my negatives come close to being over exposed.

I think a good course of action will be an exposure test in shade removing the slide 1/4 out thereby stacking exposures to see where the good thick negative lies, this will determine if my meter is off and roughly how many stops.

Once I get that established maybe then try playing with Dev times again.

I get pretty decent results in other formats so I think it has to be something in LF that is variable, and that would be Dev.

RodinalDuchamp
18-Apr-2015, 15:22
I will run a test tonight if I can. A controlled lighting indoor shot. 2 shots both at the same exposure but developing one at 8 min and a second at 13 min to see what happens.

jeroldharter
18-Apr-2015, 15:31
You did not mention the dilution or temperature of the developer. Possibly both are too low.
You should do an exposure test with bracketed exposures and varied development times (fairly simple with tray development) to ferret out your problems.

RodinalDuchamp
18-Apr-2015, 15:32
You are right. 1:1 500ml h2O + 500ml D76 at 72* sorry I'm american I don't know what that is in C

Kevin J. Kolosky
18-Apr-2015, 15:35
how are you measuring your negatives to determine that you have incorrect exposures? Do you have access to a densitometer?

Merg Ross
18-Apr-2015, 15:36
D-76 straight, or diluted 1:1? At 1:1 my standard time is around 13 minutes, several sheets in trays with constant shuffling.



+1

Gary Beasley
18-Apr-2015, 15:42
How old is your film and are you sure you are not shooting through the base of the film?
I've had expired film that would not develop to full highlight density for anything.
Also have you tested your developer to be sure it's still good? One reason I like Rodinal, it's indestructible and you start fresh every time.

RodinalDuchamp
18-Apr-2015, 15:48
How old is your film and are you sure you are not shooting through the base of the film?
I've had expired film that would not develop to full highlight density for anything.
Also have you tested your developer to be sure it's still good? One reason I like Rodinal, it's indestructible and you start fresh every time.
I am holding the film in my right hand dropping it into the holder while I can feel the notches with my right index finger. I am almost certain thus is the correct way.

RodinalDuchamp
18-Apr-2015, 15:50
how are you measuring your negatives to determine that you have incorrect exposures? Do you have access to a densitometer?
No I do not have access to a densitometer.

This is being determined by visually inspecting the negatives which appear still about 1-2 stops thin on average. This is causing me to have to use too much contrast in printing leading to decreased tonal separation.

RodinalDuchamp
18-Apr-2015, 15:51
The film and developer are new stock. And this has happened across several batches of film and developer so that rules them out.

RodinalDuchamp
18-Apr-2015, 15:52
I am thinking the problem lies somewhere between a possible meter error/calibration since it is fairly old both of my meters are fairly old both spot and incidence or underdevelopment.

sanking
18-Apr-2015, 16:27
Can we assume that you are loading the film in the holders correctly, i.e. with the emulsion side up?

If you load it the other way the anit-halation backing of the film will result in under-exposure errors of up to 3-4 stops.

Sandy

RodinalDuchamp
18-Apr-2015, 16:34
I have watched videos, had someone check me using old film, and have been instructed on how to load so I am fairly certain to the point that this could not be a factor. It is more likely that I would leave a lens cap on. 132616

Kevin J. Kolosky
18-Apr-2015, 19:59
No I do not have access to a densitometer.

This is being determined by visually inspecting the negatives which appear still about 1-2 stops thin on average. This is causing me to have to use too much contrast in printing leading to decreased tonal separation.

You need to get one foot on a rock before you start worrying about printing contrast. restart by shooting one tone. Shoot a black card in shade and try to get your zone 1 exposure to be about .10 above film base plus fog. Once you get that you can start worrying about development length to control what you are getting at the other end of the scale.

Lenny Eiger
18-Apr-2015, 20:01
My negatives are thin even though I believe I am exposing adequately.
Tri-x 320 @ 200 developed 8 minutes in trays with D76

One of the more successful exposures I have attained was during morning light 9-10 am. The exposure was F32 1/4 sec @ 200


Coupla things....

f32 at 1/4 sounds a little on the "not quite so exposed" side for what you describe... probably not the issue.

What temperature are you using for developing?
How much developing solution are you using for how many negs in the tray?

Lenny

RodinalDuchamp
18-Apr-2015, 21:03
I shot these with my digicam held up to a light (not the best but im desperate)

Randy Moe
18-Apr-2015, 21:11
Where are you?

You need local help.

RodinalDuchamp
18-Apr-2015, 21:13
Where are you?

You need local help.
Miami or homestead.

RodinalDuchamp
18-Apr-2015, 21:16
Couldnt upload full test today will try tomorrow. All shot at f8 asa 200 3 second intervals, first processed 8 min second sheet processed 10 min.

RodinalDuchamp
18-Apr-2015, 21:24
I shot these with my digicam held up to a light (not the best but im desperate)
Meter told me 3 sec measured at the gray card on the table.

RodinalDuchamp
18-Apr-2015, 21:31
Coupla things....

f32 at 1/4 sounds a little on the "not quite so exposed" side for what you describe... probably not the issue.

What temperature are you using for developing?
How much developing solution are you using for how many negs in the tray?

Lenny
72* 8 min _d76 1:1

500ml d76 : 500 ml h2o

6 neg per tray at a time constant figure 8 agitation

Randy Moe
18-Apr-2015, 21:37
This reminds me of a stupid mistake I once did or found. I forget the details of how I did it.

But i remember taking the camera apart, back off, lens board off and looking at everything.

I somehow had a full piece of 4X5 film stuck inside, that must have come loose from bad loading of a film holder. I used to not get the film under both slots and one side would be loose and the DS caught it. I did that over and over again. I have very little feeling in my fingertips.

Do the DS put out trst an inch at at time, bigger steps of exposure. Do it wrong again but more wrong.

Take everything apart. hold the lens up to a light and fire it at all speeds while looking through all the possible apertures.

Aren't there any LF people in Miami?

RodinalDuchamp
18-Apr-2015, 21:40
Randy did you see the example I posted?

Randy Moe
18-Apr-2015, 21:41
Randy did you see the example I posted?

yes, it all looked the same

Randy Moe
18-Apr-2015, 21:43
and that 2.5 stops only, you need to try 10 stops difference

Randy Moe
18-Apr-2015, 21:44
wait only 1.5 stops

RodinalDuchamp
18-Apr-2015, 21:45
3 sec interval 4 interval. 4 stops.

Randy Moe
18-Apr-2015, 21:45
3,6,12, 24, 48. 96, seconds is 6 stops

Randy Moe
18-Apr-2015, 21:46
3 sec interval 4 interval. 4 stops.

3,6,9 is not 4 stops

RodinalDuchamp
18-Apr-2015, 21:47
Ah. Aha. So 3,6 9 12. Is the, 1 2 2.5 3

RodinalDuchamp
18-Apr-2015, 21:48
I believe we are making progress

RodinalDuchamp
18-Apr-2015, 21:49
I can re test
Tomorrow

Randy Moe
18-Apr-2015, 21:52
I can re test
Tomorrow

double the time each step

See you tomorrow, by then somebody will tell me i am all wrong too

:) Good Night!

jeroldharter
18-Apr-2015, 23:01
I am out of film now. However, part of the fun of film was learning where the mischief was and eliminating it. I hope you realize you are having fun figuring this out.

RodinalDuchamp
19-Apr-2015, 04:21
Well I just learned that at 13 minutes the negative appears much richer than at 8 minutes without detriment it seems

RodinalDuchamp
19-Apr-2015, 04:52
Well I just learned that at 13 minutes the negative appears much richer than at 8 minutes without detriment it seems
I will be posting the rest of the test when I get a chance, I am off to work soon. I placed a gray card in the middle of the scene with a white card behind it. It was exposed in the second frame so 6 seconds. That is the exposure which I believe looks the best. What do y'all think?

That means my meter reading is one whole stop too thin on the negative. I also like what's happening at 13min development.

Ken Lee
19-Apr-2015, 05:05
What do y'all think?

Tri-X in D-76 1:1 has been tested and documented ad nauseum. If you are having problems either you are metering wrongly, there's something in your water, or your thermometer needs calibration.

13 minutes at 72 degrees for D-76 1:1 is more an like N+1 time. It's not uncommon for those who underexpose their film to subsequently over-develop it.

If you want to use the Zone System you might find this article helpful: http://www.kenleegallery.com/html/tech/testing.php

RodinalDuchamp
19-Apr-2015, 05:18
My thermometer is not calibrated. I can only test it against others which seem to be fairly close to reading the same within a degree.

RodinalDuchamp
19-Apr-2015, 05:19
Tri-X in D-76 1:1 has been tested and documented ad nauseum. If you are having problems either you are metering wrongly, there's something in your water, or your thermometer needs calibration.

13 minutes at 72 degrees for D-76 1:1 is more an like N+1 time. It's not uncommon for those who underexpose their film to subsequently over-develop it.

If you want to use the Zone System you might find this article helpful: http://www.kenleegallery.com/html/tech/testing.php
I have been developing at 8 min. For the test I posted I developed to 13 min.

RodinalDuchamp
19-Apr-2015, 05:24
I use only VC paper. Wet printing. I don't have access to a densitometer, judging the old fashioned way looking at the negative which seems thin. The prints are requiring too much contrast which compresses the tonal range. Without enough contrast they become muddy the tones don't separate.

Ken Lee
19-Apr-2015, 05:28
Are you exposing your prints for the black film edge ?

How long do you develop your paper, in which developer at what dilution and temperature ?

We need a standardized approach - always the same - for testing.

What kind of light source for the enlarger ?

RodinalDuchamp
19-Apr-2015, 05:32
Ken I appreciate your help and feedback but we are now introducing a myriad of variables. I have had the negatives evaluated by other LF photographers and it was agreed the problem lies in the negative itself. I ran a test stacking exposures and developed at 2 times I will try to post both here in a few minutes. Hopefully something can be learned from that test. I am not ready to test other factors as the lab I have used is at a school where others are making good prints from good negatives. The difference is in their developing which differs from my own due to using different films/formats etx

RodinalDuchamp
19-Apr-2015, 05:41
Here are both tests.

Ken Lee
19-Apr-2015, 05:56
Just looking at negatives can be deceptive. Looking at JPG files of photographs of negative on a computer monitor can be even more confusing. We want to reduce the number of variables, not increase them :)

If we are trying to determine film speed or developing times, simply "eyeballing" the negatives is of questionable value at best.

If we are making negatives for darkroom printing, the best way to judge them is to print them, with all variables under control: Make a print on Number 2 paper (or with Number 2 filter) giving just enough exposure to render the film edge at max black. Be sure to develop all your prints for the same time, using the same brand + dilution of developer at the same temperature. If you are enlarging your negatives, then make your test prints at the same size, using the same enlarger lens etc.

RodinalDuchamp
19-Apr-2015, 06:10
The variables you mentioned paper, contrast controls, chemistry for printing has remained constant.

Unfortunately a densitometer is not available to me. I wouldn't say visually evaluating negative is questionable, especially when the changes are quite significant.

If I had other resources I would go to them, but I figured at the very least someone on the forum would be able to point me in the right direction.

This test was suggested by someone earlier in the thread and seemed like a sensible place to start.

Hopefully someone will try to interpret the test better than I can.

Gary Beasley
19-Apr-2015, 06:12
One thing I notice is no adjustments for reciprocity failure when metering. Have you checked for the adjustments for this film for long exposures? I have seen instances where a one stop longer exposure by the meter needs to be doubled or quadrupled to overcome reciprocity characteristics of the film. Thats one reason I love Acros 100 when I could get it, low reciprocity failure.

RodinalDuchamp
19-Apr-2015, 06:16
One thing I notice is no adjustments for reciprocity failure when metering. Have you checked for the adjustments for this film for long exposures? I have seen instances where a one stop longer exposure by the meter needs to be doubled or quadrupled to overcome reciprocity characteristics of the film. Thats one reason I love Acros 100 when I could get it, low reciprocity failure.
You are right. At 1 second Kodak recommends +1 stop = 2 seconds. So my 3 second exposure should have been 6 seconds, which is where I believed the best density occurred in the 13 min development.

However Kodak recommends only 6 3/4min Dev but this is at box speed

RodinalDuchamp
19-Apr-2015, 06:18
For what its worth I never trust box ratings.

Peter De Smidt
19-Apr-2015, 06:50
Don't do film development/exposure tests at times where reciprocity is a problem. The same thing applies to bellows extension. You have to nail down your base exposure and development first. After that, you can then do tests for reciprocity and figure out how to deal with bellows factor. In another thread, I told you how to do this. You're having all these problems because you seem reluctant to do basic, straightforward tests. Get a matte black card. Get a matte white card. Go outside. Focus your camera on infinity. Place the black card in open shade so that it is evenly lit. Point your camera at it. Do not adjust focus. (When you're focused at infinity there will be no reciprocity problems.) Set your meter for 1/4th the box speed, meter the card, and place it on Zone I, i.e. meter the card and give 4 stops more exposure, using a shutter speed in the 1/8=1/60 range. Shoot a series of 8 negatives, giving 1/3 less exposure for each one. This will match film ISO ratings. For example, suppose that your film is rated at EI 100. The first neg equals an EI of 25, the second 32.... Move the white card into sun such that it is evenly lit. Set meter to 1/4 the box speed. Meter the card and place it on zone VIII. Shoot the same series, each one with 1/3 less exposure. Develop the film at your best guess using a standard process.

Evaluation is easy if you use a densitometer, which someone near you will have. Zone one should be about .15 above film base plus fog, and zone VIII should be about 1.3 above film base plus fog. The nice thing about this is that there's no guessing. But if you refuse to find someone to read your negatives, then look at the Zone I series. Put them in order. Now look through them in good light. Find the first negative where you can clearly see that Zone I is different from film base plus fog. It'll be faint. If you look at negs where you gave progressively more exposure, the different will become greater. The properly exposed neg will be two or three steps from the one where you can just barely see the difference. So if you can see the difference first at EI 64, your true EI would be 40 or 32.

As said before, the Zone VI negs should be 1.3 or so above film base plus fog, a little less for a condensor enlarger. You can do what ken suggests, making what Fred Picker called "a proper proof", but this is much less direct than using a densitometer. The reasons are that grade II papers aren't necessarily grade II with your process. You determine this by using a step wedge and counting the steps. See Way Beyond Monochrome. The second reason is that it's hard for us to see just when the right black appears. In any case, you take a clear negative that's been processed. You Zone I series should have one. Print a test strip with 1/3 stop increments. Find the one that's the first maximum visual black in normal viewing light after the paper has dried. That will tell you your stand printing time for a proper proof. Now use the Zone VIII negative that pairs with the Zone I that you determined. Print this negative, making sure that half the printing paper sheet is covered. Process. Dry. You should see a fairly small difference in tone between the Zone VIII area and paper white. If there isn't a difference, then you developed to much. Make another Zone VIII negative, just one, and develop for 20% less. Make a proof and evaluate. If there's a huge difference between the Zone VIII and paper white, then you need to develop more.

Box speeds and development times are nothing more than starting points. My T100 and Acros EI is 80 for normal development. I recently tried Delta 100, which is labeled the same speed as the others, but it gives me a true film speed in Pyrocat MC of 25.

Michael R
19-Apr-2015, 07:01
For what its worth I never trust box ratings.

Why not?

Bill Burk
19-Apr-2015, 07:57
For what its worth I never trust box ratings.

RodinalDuchamp,

For what it's worth, I always do... For fresh film developed to the ASA contrast parameters.

What I never trust (beyond taking an initial starting point) is the development time recommendations.

Thank goodness Hurter and Driffield came along in 1890 to give us H&D curves... before then you really couldn't trust box ratings.

RodinalDuchamp
19-Apr-2015, 08:15
These are preferences everyone has. Mine is to rate this film at 200. As can be seen even rated at 200 the film has great latitude.

I'm thinking I have been under developing.

Bill Burk
19-Apr-2015, 08:23
RodinalDuchamp,

In my case, since I'm drawing curves, it's what the film "is".

Rating the film at 200, is a preference. But the film "is" 400.

My preference is to use 250, so I get what you are saying...

Now as for under developing... assuming that's the issue... we need to help you find your time.

You say you don't have a densitometer. Do you have a spotmeter and a light box? I often recommend shooting two shots - two f/stops apart in exposure - and then looking at the resulting two negatives with a meter. If the difference between them is one f/stop on the meter, then you have a 50% contrast... (two f/stops of exposure difference results in one f/stop of density difference) which is reasonably close to a normal contrast.

ic-racer
19-Apr-2015, 19:50
You can test your system for adequate exposure by exposing a sheet through the camera to a uniform target at zone 1. If the resulting negative has about 0.15 log d density (that is, it causes 1/3 of a stop decrease compared to a blank frame when placed over your light meter) you are exposing correctly.

Once that is sorted out you can expose a zone VIII frame and print it at the enlarger time required to make maximum black from the blank frame. The print should be just off white if development is correct for that paper.

jnanian
20-Apr-2015, 21:34
hi rd

is your film new / fresh film ?
aged film sometimes loses speed.

RodinalDuchamp
20-Apr-2015, 21:37
Still running tests this time in more accurate scenery with faster shutter speeds to eliminate reciprocity issues.

RodinalDuchamp
22-Apr-2015, 17:22
I think I should have mentioned I am using constant agitation for those 8 minutes.

I ran a test at school with a different negative and the results seemed to have greater density and overall more contrast at 8 minutes. Maybe my thermometers are to blame?

I'll have to pick up some new ones and start over.

Bruce Barlow
23-Apr-2015, 02:53
I've found Sunny 11 to work better than 16....

+1, especially if your negatives are thin. Try it versus an exposure you meter. They'll either be the same or different (I bet diffrent), and the difference will be a clue about what's going on with the metered ones.

bob carnie
23-Apr-2015, 06:17
Was there not a quote from Brett Weston something like ( what would happen if the damm thing broke)

Jac@stafford.net
23-Apr-2015, 06:53
I think I should have mentioned I am using constant agitation for those 8 minutes.

So much for stand development.

RodinalDuchamp
23-Apr-2015, 06:56
Well I was using stand Dev for times when o was working at night to try and get as much shadow development as possible while controlling the highs. I am now using D76 as my standard developer with a standard process. I understand some people follow an agitation schedule like 1 minute constant agitation then 5 seconds every 30 seconds. I found the latter to produce inconsistent sky tones and haven't had a problem since switching to constant tray agitation. Well other than thin negatives.