A observation about reading newsprint through highlights

[rpavich]

Another thing... You've proved that the manufacturers do actually know what they are doing! Their recommendations, film speed and development times, generally work out OK... So, if we rely on their suggested settings we can concentrate on the art of photography while applying the craft as we understand it should be... Fred

I was sort of surprised myself. I think the reason that I started shooting so much over exposed was that I was so erratic and uneven when I first started shooting that I needed a lot of cushion, a lot of room for error so that i wouldnt grossly under expose, but now im less inclined to underexpose and so my exposures have all been several stops over consistently.

 

[Ozxplorer]

I don't really think exposure do add density to negatives. Its the development time and agitation that adds the density. Temperature do play a role too.

Agreed, temperature does make a difference... to contrast but not density. But I beg to differ about your view regarding the relationship between exposure & density. It is very easy to confuse the terminology used concerning the cause & effect of density and that of contrast. If you have a look at images in post #21 - a contact print, you will notice the detail becomes less obvious the more the film frame is over exposed. i.e. The film rated @ ISO 400 yields detail of the target whereas the same film frame over exposed by 2 stops - ISO 100, does not. Thus, it can be seen that exposure changes density all else being the same. Also, it will need a longer print exposure time for the ISO 100 rated negative to achieve the same reflectance outcome compared to the time used for the contact printed ISO 400 negative. Careful control over the development process allows one to control the overall contrast range of the negative so as not to lose detail in the highlights - the exposure being made for the shadow detail. Fred

 

[rpavich]

Well, that was interesting though I don't know what it means but I'll give you some numbers anyway and you can fill me in.

I took a reading from the "good" negatives that you say in the contact sheet exposures that I printed at grade 2 for Dmax. They would be(with their density readings):

Box speed developed at manufacture's time. (1.67 for the brightest highlight / .29 for the deepest shadow)

1 stop over developed at 15% less than M-time. (1.76 for the brightest highlight / .23 for the deepest shadow)

2 stops over developed at 30% less than M-time. (1.61 for the brightest highlight / .5 for the deepest shadow)

I also went back to a set of negatives that I knew printed nicely on grade 2 and did a density reading there also.

It read 1.07 for the brightest highlight / .12 for the deepest shadow

Like I said, I haven't the faintest idea what these numbers should be nor what they imply but I can say that the negatives where I strived to limit the development to bring in the contrast didn't print nearly as well, it was a struggle. In contrast to the older negative which basically printed itself.

 

[Ozxplorer]

Hello again... I would interpret your data as follows: a 0.3 density approximates 1 stop thus if you divide the low reading into the high reading of each test then then you arrive at the brightness range of the negative in "stops" of exposure. So, at box speed, normal development, the range is around 6 (5.76) stops which is perfect for printing on a mid grade paper. The next test, 1 stop over & under developed 15% yields in this instance a 7.65 stop range - a negative with clearly a longer tonal range with more shadow and highlight detail. And, the 3rd the result a much longer mid tonal range. Probably tests 2&3 will need to be printed on harder paper grades. This is my take on the information. Maybe one of our still asleep experts will chip in tomorrow.
Lastly, if you can for each of the tests measure the density of only the grey part of your "grey card" for both the 400 and 100 ISO exposures then with this information it will be possible to calculate a "ball park" contrast index - a measure of your development process. Fred

 

[rpavich]

Hello again... I would interpret your data as follows: a 0.3 density approximates 1 stop thus if you divide the low reading into the high reading of each test then then you arrive at the brightness range of the negative in "stops" of exposure. So, at box speed, normal development, the range is around 6 (5.76) stops which is perfect for printing on a mid grade paper. The next test, 1 stop over & under developed 15% yields in this instance a 7.65 stop range - a negative with clearly a longer tonal range with more shadow and highlight detail. And, the 3rd the result a much longer mid tonal range. Probably tests 2&3 will need to be printed on harder paper grades. This is my take on the information. Maybe one of our still asleep experts will chip in tomorrow.
Lastly, if you can for each of the tests measure the density of only the grey part of your "grey card" for both the 400 and 100 ISO exposures then with this information it will be possible to calculate a "ball park" contrast index - a measure of your development process. Fred

Ahh...very good! Thanks so much for explaining that.
I'll do that today.

 

[rpavich]

Ok...here goes.
Grey card numbers for each ISO at each dev time.

Box speed at stock dev time
1.3

ISO 200 at stock dev time
1.46

ISO 100 at stock dev time
1.7

---------------------

Box speed at -15% less dev time
1.31

ISO 200 at -15% less dev time
1.49

ISO 100 at 15% less dev time
1.7

-----------------------

Box speed at 30% less dev time
.89

ISO 200 at 30% less dev time
1.08

ISO 100 at 30% less dev time
1.28




There they are in all their glory. As I said, they don't mean much to me at this point, I welcome your observations.

 

[RalphLambrecht]

I don't really think exposure do add density to negatives. Its the development time and agitation that adds the density. Temperature do play a role too.

of course exposure adds density;so does extending dev time and raising temp.expose for the shadows and dev for the highlights;

 

[RalphLambrecht]

Ok...here goes.
Grey card numbers for each ISO at each dev time.

Box speed at stock dev time
1.3

ISO 200 at stock dev time
1.46

ISO 100 at stock dev time
1.7

---------------------

Box speed at -15% less dev time
1.31

ISO 200 at -15% less dev time
1.49

ISO 100 at 15% less dev time
1.7

-----------------------

Box speed at 30% less dev time
.89

ISO 200 at 30% less dev time
1.08

ISO 100 at 30% less dev time
1.28




There they are in all their glory. As I said, they don't mean much to me at this point, I welcome your observations.

the negative density target value for Zone V is 0.72

 

[RauschenOderKorn]

It read 1.07 for the brightest highlight / .12 for the deepest shadow

1.07-.12 equals an overall contrast of about 0,95.

If this printed nicely on your grade 2 paper, then things are "just all right", beause grade 2 paper is intended to print a negative with a contrast of 1 nicely.

 

[Arvee]

Wow, them's some bulletproof negs!

Gray card readings want to be between .65 and .75, depending on whether you use condenser or diffusion enlarger. Highlight densities typically shouldn't exceed 1.15 to 1.20 for 35mm negs

As Ralph noted, I think you have some exposure issues (meter or shutter problems). Could also be densitometer is not reading properly. Have any 21 step Stouffers transparency strips? I think you definitely need one for reference.

Or you're agitating "cocktail shaker" style, but I don't even think that would give you numbers like you're seeing..

Get Ralph's book "Way Beyond Monochrome" or Horenstein's "Beyond Basic Photography;" both are excellent.

 

[rpavich]

the negative density target value for Zone V is 0.72

Thankyou.

1.07-.12 equals an overall contrast of about 0,95.

If this printed nicely on your grade 2 paper, then things are "just all right", beause grade 2 paper is intended to print a negative with a contrast of 1 nicely.

Well, that gives me something to aim for.

Wow, them's some bulletproof negs!

Gray card readings want to be between .65 and .75, depending on whether you use condenser or diffusion enlarger. Highlight densities typically shouldn't exceed 1.15 to 1.20 for 35mm negs

As Ralph noted, I think you have some exposure issues (meter or shutter problems). Could also be densitometer is not reading properly. Have any 21 step Stouffers transparency strips? I think you definitely need one for reference.

Or you're agitating "cocktail shaker" style, but I don't even think that would give you numbers like you're seeing..

Get Ralph's book "Way Beyond Monochrome" or Horenstein's "Beyond Basic Photography;" both are excellent.

But thats the thing...they arent at all bulletproof, you can see through the highlights and there isnt any contrast. I'm sure that im probably measuring something wrong.
I'm using my analyser pro to measure through the edge of the neg to get base+fog, then measuring the highlight or whatever.

I have a tiny step wedge, yes

Maybe it would help if i took a picture of my negatives and posted that.

 

[Arvee]

Something's definitely not kosher!

If using a proper gray card set up in good light and you are using the reflected meter reading that does not include any specular reflections or glare (reading taken at a 45 or so), with manufacturer's recommended development and ISO rating, you should be seeing around .25 - .30 film base + fog, .70 - .75 for middle gray, depending on the film manufacturer. FB+F should be measured between frames or on the unexposed leader.

Visually, how do the gray card renditions on your negs compare with the Stouffer step wedge? You should be able to make a pretty good eyeball comparison on a light table.

 

[rpavich]

Something's definitely not kosher!

If using a proper gray card set up in good light and you are using the reflected meter reading that does not include any specular reflections (reading taken at a 45 or so), with manufacturer's recommended development and ISO rating, you should be seeing around .30 film base + fog, .70 - .75 for middle gray. FB+F should be measured between frames or on the unexposed leader.

Visually, how to the gray card renditions on your negs compare with the Stouffer step wedge? You should be able to make a pretty good eyeball comparison on a light table.

Ahh! Good question, ill get to checking, it shouldnt be too long

 

[Arvee]

If I remeber correctly, step 6 is .75 and each step is .15 on the 21 step wedge. Check to see how close your gray card renditions on the negs are to step 6. Step 9 is 1.20 and this is what you are shooting for as a max highlight reading. See if you can read newsprint through step 9.

When in school, if I turned in an assignment negative with a highlight density reading greater than 1.20 (not including speculars), it was an automatic 'F' for the assignment!

 

[rpavich]

If I remeber correctly, step 6 is .75 and each step is .15 on the 21 step wedge. Check to see how close your gray card renditions on the negs are to step 6. Step 9 is 1.20 and this is what you are shooting for as a max highlight reading. See if you can read newsprint through step 9.

When in school, if I turned in an assignment negative with a highlight density reading greater than 1.20 (not including speculars), it was an automatic 'F' for the assignment!

Ok Here is the first strip put on my iPad as a light box next to the step wedge. I took the picture with my iPhone and brightened it up in lightroom because it was a bit dark.

I cut and pasted the step wedge portion and moved it around to make it easier to judge what tone the grey card matched on the step wedge.

To my eye, it's about a dead perfect match with the #9 step.

This strip is the normally developed strip. I chose the normally exposed shot to match it to.

 

[Arvee]

Xlnt, we can now see what you have. I'm thinking the negs are overexposed. Can you provide exact details for exposure and development? Rebate also looks a little hot compared to my test negs.

 

[rpavich]

And for referene, here is the

Xlnt, we can now see what you have. I'm thinking the negs are overexposed. Can you provide exact details for exposure and development?

Ok.

The exposure was taken by filling the frame with the grey card only and then centering the meter as well as I could and then setting the camera accordingly. I don't recall what it was though, sorry.

The film is HP5.
The dev time is 12 minutes at 20c.
I agitate for 1 minute and then for 10 seconds every minute thereafter. As I recall, the temp of the dev and water and fix was a degree or two lower so I slid up the scale in the massive dev chart. I think that it was about 18.5c or there about, I don't remember.


The next two pictures are the exact same (because they were taken from the same roll of film) and then just cut short in development by 15% and then by 30%.


Here is the 15%. The #8 step seems to correspond to the grey card.

Here is the 30% less dev time strip compared to the wedge. It appears that the #6 matches.

 

[rpavich]

So my question is; How do I move zone V up the scale to where it needs to be while retaining the ability to print at grade #2 or 2.5?

I gotta say, these negs aren't even close to the density that printed at grade 2 perfectly today. Here is a comparison of what printed perfectly at grade 2. I can see it's a lot different than these. It was HP5 at 800 in microphen. It seems to be a LOT more contrasty (it printed on grade 2 and these print at 5 or 4 at the least to get anything like blacks)

The two shots I printed were 36 and 37. On 36 I metered on the deepest part of the shadow on the table and on the very light highlight that you see (it's just about pure white in real life.)

The comparison negative in the photo is the -30% one.

 

[Arvee]

Okay, been puzzling the data provided. I'm going to assume that the Microphen was diluted 1 to 1; that's the dilution for 12 minutes. That said, having to reduce development by 30% to get the gray card on zone V tells me you are overexposed by about two stops. The gray card test exposure should be 16/500 when photographed in clear sky sunlight. Have you checked your meter in the camera? Is the exposure compensation dial moved off zero?

If you didn't dilute the Microphen 1:1 and developed 12 minutes you would get results close to what you are seeing.

Edit: I did notice in your last post that when I zoomed on the iPad the rebate info is darker on the gray card strip vs. the non-test strip. The top strip rebate info looks like my Ilford film; the test strip appears to be developed more.

Edit 2: I perhaps made an incorrect assumption that Microphen was the developer used. Please clarify.

 

[rpavich]

Okay, been puzzling the data provided. I'm going to assume that the Microphen was diluted 1 to 1; that's the dilution for 12 minutes. That said, having to reduce development by 30% to get the gray card on zone V tells me you are overexposed by about two stops. The gray card test exposure should be 16/500 when photographed in clear sky sunlight. Have you checked your meter in the camera? Is the exposure compensation dial moved off zero?

Ahh..I should have said it was XTOL 1:1, sorry.
Also, I checked my meter and it's dead on. (checked it with a sekonic meter) However that doesn't mean I metered it as well as I could I guess. I should have verified it with the sekonic at the time.

If you didn't dilute the Microphen 1:1 and developed 12 minutes you would get results close to what you are seeing.

Edit: I did notice in your last post that when I zoomed on the iPad the rebate info is darker on the gray card strip vs. the non-test strip. The top strip rebate info looks like my Ilford film; the test strip appears to be developed more.

Ok...something is really wrong.

I got to thinking that I'd also shot a few test shots of Bergger film that someone gave me during this time frame and so I thought I'd take a look at those negs with the step wedge also, just for reference. Well...that's weird. It looks much different.

I'm sure that I shot it at box speed and dev'd it per directions because I was testing it. I also metered it using the sekonic meter.

When I did the density check I got .67!

I shot the same target as with the Ilford film and also put a piece of white notebook paper and my black laptop case next to it for reference. Not only does it look much different (not nearly as dense in the zone V) it printed beautifully at grade 2 with the time for Dmax (maybe a slight bit too long but really nice.)

The grey target looks like it corresponds to #6 on the step wedge too. (with a box speed shoot and manufacturer's time/temp for dev)

So I guess my question is: are my other shots just grossly overexposed even though I THOUGHT that they were correctly exposed? Is that the basic issue?

 

[Arvee]

Anytime you have to reduce development by 30% to get middle gray on Zone V, that tells me that the film was overexposed by two stops or the developer wasn't diluted properly. That's the only conclusion I can reach with the current indications.

 

[rpavich]

Anytime you have to reduce development by 30% to get middle gray on Zone V, that tells me that the film was overexposed by two stops. That's the only conclusion I can reach with the current indications.

OK...thanks. That's what appears to be happening.

I really appreciate all of you bearing with me on this investigation. Thank you very much. I really learned a lot because of this.


Incidentally, I ran out of HP5 (go figure) and so when I get more in, I'm going to re do this test and double check the exposure with my sekonic meter while I do it.

 

[Arvee]

I would suggest at this point that you repeat the test with D76 undiluted. Film manufacturers base their specs on how the film behaves with this standard developer. All other developers will introduce some variables which can throw off results.

 

[rpavich]

I would suggest at this point that you repeat the test with D76. Film manufacturers base their specs on how the film behaves with this standard developer. All other developers will introduce some variables which can throw off results.

Ok. I happen to have a fresh bag of D76, I'll mix up and use that.

 

[Arvee]

Previous post deleted.

Edit: actually, I am mistaken in the deleted post. The step wedge is calibrated in 1/2 stop increments. So the white paper and the black laptop are actually about 1 stop away from middle gray.