Overdeveloping?

Hi everyone!

 

So I have been getting some scans done and all the colour shots (lab processed) look great but the B&W ones (developed by me) look way too bright. I can make some improvements by fiddling around with my scanner settings but they are still too bright for my liking. All pics were taken on the same camera so if the colour ones are ok I think that the meter is not an issue (I also tried shots on another camera and same result.) So, I'm guessing that this is a development issue and that I've been probably overdeveloping? I thought my chemical temps were spot on and I don't agitate like a maniac. I also followed development times as shown on the Massive Development Chart. So for example HP5+ in D76 (stock) for 7.5 mins @ 20 deg. Maybe I should knock of some time? Can overdeveloping cause what looks like an overexposed pic?

I find that when I scan B&W negatives, I have to "enhance" most of them in a photomanipulation program - I use an ancient program called "Photostudio 5", that came with a Canon digital I bought years ago. I don't expect negatives to look perfect straight off the scanner (a Canon Canoscan).

I find that when I scan B&W negatives, I have to "enhance" most of them in a photomanipulation program - I use an ancient program called "Photostudio 5", that came with a Canon digital I bought years ago. I don't expect negatives to look perfect straight off the scanner (a Canon Canoscan).

Thanks for the reply John! I was wondering about that because I can use my Camera Raw and get the files to look great, good tones, contrast etc nothing blown out. I usually need to decrease exposure by about 2 stops though, is this normal? Is there some inherent difference between B&W and colour film besides the obvious? Not sure why only the B&W scans suck.

You need to check the density of the negatives to find if they're being overdeveloped. Scans tell you very little, since scanner software varies too much.

 

A well exposed and properly developed negative shouldn't exceed a density of 2.0 by very much, with a base level (transparent bits) of no more than 0.2D. This isn't easy to judge by eye without experience, but as a rough guide: When the negative is placed in contact with a newspaper or printed book page, you should be able to just read the text through the densest parts of the neg. While the lightest parts of the film should give no more than a very pale grey shading.

 

If you can't make out the printed letters at all in the densest parts, then chances are the film is overdeveloped.

 

It might help if you gave more detail. Such as: What are you using to measure the developer temperature, and which scanner are you using? What scanner software do you use, and at what settings?

 

Maybe posting some examples might help as well.

You need to check the density of the negatives to find if they're being overdeveloped. Scans tell you very little, since scanner software varies too much.

 

A well exposed and properly developed negative shouldn't exceed a density of 2.0 by very much, with a base level (transparent bits) of no more than 0.2D. This isn't easy to judge by eye without experience, but as a rough guide: When the negative is placed in contact with a newspaper or printed book page, you should be able to just read the text through the densest parts of the neg. While the lightest parts of the film should give no more than a very pale grey shading.

 

If you can't make out the printed letters at all in the densest parts, then chances are the film is overdeveloped.

 

It might help if you gave more detail. Such as: What are you using to measure the developer temperature, and which scanner are you using? What scanner software do you use, and at what settings?

 

Maybe posting some examples might help as well.

Thanks a lot Joe! So, it looks like I have indeed overdeveloped. Just tried the newspaper test and colour negs I can read a bit through darkest parts but with B&W negs I couldn't read through it whatsoever. So more developing practice needed :) Using a digital thermometer to measure temp and scanner is plustek 8200i, I'm still trying out different settings.

 

Thanks for your help!

Digital thermometers, especially cheap ones, can be very deceptive. Most of them read to tenths of a degree, but can be out of calibration by quite a few degrees.

 

Even checking it at freezing and boiling point isn't foolproof, since boiling point varies with altitude, and there's no guarantee that the readings are linear in between.

 

Glass - mercury thermometers are usually better calibrated around room temperature, but they're obviously much more fragile and a complete PITA to clean up if they get broken.

 

Medical thermometers have to be quite accurate, but only around blood-heat. So maybe buying a medical thermometer and checking your existing one against it in water at body heat might be a good idea.

 

You could then find out if your existing thermometer's reading low, and add a correction factor to it at 20 C. Or just cut your development time.

 

IME the amount of agitation makes very little difference to development density, but it does affect how even the density is, and can prevent streaks, air-bubbles and other nasties.

 

P. S. The Plustek 8200I uses Silverfast software I believe. My brief encounters with Silverfast didn't impress me at all. You could try Ed Hamrick's Vuescan and see if results improve. I think it's still available for free trial - with a watermark that gets removed when you buy.

Edited November 2, 2018 by rodeo_joe|1

Digital thermometers, especially cheap ones, can be very deceptive. Most of them read to tenths of a degree, but can be out of calibration by quite a few degrees.

 

Even checking it at freezing and boiling point isn't foolproof, since boiling point varies with altitude, and there's no guarantee that the readings are linear in between.

 

Glass - mercury thermometers are usually better calibrated around room temperature, but they're obviously much more fragile and a complete PITA to clean up if they get broken.

 

Medical thermometers have to be quite accurate, but only around blood-heat. So maybe buying a medical thermometer and checking your existing one against it in water at body heat might be a good idea.

 

You could then find out if your existing thermometer's reading low, and add a correction factor to it at 20 C. Or just cut your development time.

 

IME the amount of agitation makes very little difference to development density, but it does affect how even the density is, and can prevent streaks, air-bubbles and other nasties.

 

P. S. The Plustek 8200I uses Silverfast software I believe. My brief encounters with Silverfast didn't impress me at all. You could try Ed Hamrick's Vuescan and see if results improve. I think it's still available for free trial - with a watermark that gets removed when you buy.

So bought 2 different thermometers yesterday (medical) and they both exactly agree temp wise with each other. The thermometer which I've been using however shows a whopping 4 degrees less than the other 2 so I think this solves the problem. Thanks for your help and advice with this! Checked out vuescan, looks good! Definitely already prefer it for B&W but the colour scans look better on Silverfast imo but it is early days. Thanks again!

Good black and white negatives will normally have some parts that are easy to see through, others almost black.

 

Most films, though, are good with much more exposure (or development).

 

It might be that not all scanners can extract the image, though.

You might adjust the image with the scanner software, or with external software

after scanning.

 

If you can, try a different scanner.

 

Color negatives are different. The densities are compressed, making it harder

to judge looking at them. The compression, though, allows for good results, even

if overexposed (or overdeveloped).

The important detail in a negative should sit within a 1.8D range. Anything above 2.0D will be difficult to print or scan, and is in danger of falling into the non-linear part of the film curve where tonal separation is reduced.

 

A density of 2.0D is about the limit of being able to read print through.

 

It's a common mistake to think that a good 'thick' neg is what should be aimed for. With scanning, a bit of extra density isn't too much of an issue, since compressed highlights can be expanded with a tweak of the curves tool. But put the same neg into an enlarger and try to make a decent print.... that's an entirely different story!

The important detail in a negative should sit within a 1.8D range. Anything above 2.0D will be difficult to print or scan, and is in danger of falling into the non-linear part of the film curve where tonal separation is reduced.

 

A density of 2.0D is about the limit of being able to read print through.

 

It's a common mistake to think that a good 'thick' neg is what should be aimed for. With scanning, a bit of extra density isn't too much of an issue, since compressed highlights can be expanded with a tweak of the curves tool. But put the same neg into an enlarger and try to make a decent print.... that's an entirely different story!

 

I always thought that was what grade 4 paper, and grade 4 filters for variable contrast paper, were for.

 

Well, it seems that in the earlier days, which for me means more than 50 years ago, there was Farmer's Reducer, which is somewhat similar to the bleach used with color film. It partially, and hopefully uniformly, removes silver.

 

Not all scanners can deal with high density negatives, though. Especially ones designed for color negatives, which don't get as dense.

I always thought that was what grade 4 paper, and grade 4 filters for variable contrast paper, were for

 

- Huh? How does globally increasing contrast help with an over-developed negative that has too much contrast to begin with?

 

You'd have to do quite a lot of skilled split-grade dodging and burning to locally increase contrast in the highlights while softening the shadows and mid-tones.

 

Far better to simply get the developing right in the first place.

 

The same goes for reduction processes, which can be proportional or super-proportional. Neither will de-compress severely overdeveloped highlights.

 

"Not all scanners can deal with high density negatives, though. Especially ones designed for color negatives, which don't get as dense."

 

- I don't know of a single film-scanner that's designed specifically for colour negatives. Most of them boast of being capable of handling at least a 3.2D range or higher; needed for scanning colour slides. To get any standard B&W film to hit a density of 3.2 or above would need about a fortnight in Rodinal @ 1:25!

 

The reason for colour negative material not getting so dense is that the C-41 process is usually tightly controlled and standardised. But not always. I once had 2 rolls of Kodacolor returned from a so-called professional lab that had obviously been 'stewed' and overdeveloped. They were totally unprintable and barely useable even after scanning. I was not pleased!

In my experience, b&w negatives intended for scanning should be slightly thinner than those intended for darkroom printing. Negatives that are overexposed or overdeveloped can be very difficult to scan well. Scanners, unlike enlargers, have a fixed maximum exposure. I have made decent prints from very heavy negatives by using long exposures in the enlarger.

It is even suggested to expose or develop differently for condenser vs. diffusion enlargers.

 

i don't know if people actually do that.

 

Most films have more overexposure latitude, than underexposure, and a little more exposure,

maybe half a stop, is usually good. A lot, though, can complicate things.

It is even suggested to expose or develop differently for condenser vs. diffusion enlargers.

 

- The reason for that is the 'Callier effect', which increases contrast (non-linearly) when a collimated light source is used. The mechanism is that turbidity in the silver image scatters collimated light in proportion to the amount of silver, and the scattered light can no longer form an image. Diffuse light, OTOH, is effectively already scattered and passes through the emulsion unaltered.

 

In other words; some collimated light is lost in the highlights of the image and decreases their printed density, while shadows are largely unaffected.

 

The Callier effect is a bit overplayed, since most condenser enlargers don't use a true point-source, and therefore don't use collimated and coherent light. The usual combination of opal bulb + condensers results in a semi-diffuse source. With the result that the difference in contrast between a condenser and diffuser enlarger amounts to only about half a paper grade and is easily compensated in printing.

 

The idea that diffuser enlargers are less sharp than condenser types can also be seen to be mainly a myth.

 

It's worth noting, however, that colour and chromogenic negatives are immune to the Callier effect, since there's no silver in the image to scatter light.

 

Scanners almost never use a point source - drum scanners excepted. Therefore the Callier effect usually has no bearing on a scanner.

 

"...and a little more exposure,

maybe half a stop, is usually good. A lot, though, can complicate things."

 

- Yes. Slight overexposure is much more tolerable than over development, since contrast remains 'normal' and highlights don't become opaque.

Discussion about overdevelopment, reminds me that I was recently developing a roll of Verichrome Pan, likely not very new.

 

I have an old "Kodak Films in Rolls" which says 8 minutes, and the data sheet on the web says 5.

Times for other developers are the same for the two data sheets.

 

I don't remember which camera I used for it, though.

- Huh? How does globally increasing contrast help with an over-developed negative that has too much contrast to begin with?

 

You'd have to do quite a lot of skilled split-grade dodging and burning to locally increase contrast in the highlights while softening the shadows and mid-tones.

 

(snip)

 

Regarding grade 4 paper, I was more thinking of the case of overexposure, but either overexposure or overdevelopment gets you up to the top of the curve where contrast is lower.

 

Now, the complication is that only some parts of the scene will be so far up on the curve.

If those parts are such that dodging and burning-in can fix them, then do that.

 

There are also underexposed, or underdeveloped, negatives, at the bottom of the curve,

also with low contrast to extract with grade 4 paper.

I strongly encourage beginners (and all printers, really) to use a diffusion enlarger instead of a condenser enlarger. It's so much easier to make good prints. As Rodeo Joe explains, condenser enlargers distort the highlights. (They get brighter.) He recommends printing on lower contrast paper to compensate, but that will also lower the contrast of the midtones and shadows, which aren't distorted by the condenser. Underdeveloping the film to depress the highlights gives some relief, but it too depresses the midtones and shadows to some extent. Diffusion enlargers don't distort any part of the tonal range, so these attempts at corrections aren't necessary.

 

The simplest way to prove the superiority of diffused light is to compare a contact print with an enlargement of the same negative. Make a properly exposed contact print of the negative, then enlarge it on the same paper grade. (These should be straight prints; no dodging or burning, etc.) The diffusion prints will match tonality; the condenser prints won't. The condenser print always requires highlight and contrast corrections to approximate the tonality of the contact print. (You can perform this experiment using a condenser enlarger because contact prints always print undistorted, no matter what the light source -- there's no projection.)

 

However, I know from long experience that few people will believe the difference until they see it with their own eyes.