Is my densitometer working properly?

[Brassolini]

Hi everyone!

Many searches has led me to this forum where I’ve come across lots of good info, interesting topics and a great body of accumulated knowledge. This is why I chose to register here and post for my first time ever in a photography forum.

Photography and darkroom work is a new hobby to me but after a year of reading up and experimenting with different BW films and darkroom processes, my limited time for darkroom work made me want to take away some of the guesswork and so I got a densitometer off of eBay to read my zone test negs.

I’m really not sure that it is functioning properly, but the dealer assures me it is. I have no reason to doubt him and hoping he is right, in which case reading the values isn't as straightforward as I thought.
I made a short video to show, rather than tell what the issue is and I’m hoping someone in this forum has experience with this and will be able to enlighten me!

Link to video: https://www.dropbox.com/s/2ewvhc9vqfeoiof/Fil 10.11.2017, 13 37 21.mov?dl=0

So to be clear, my question is:

“Is my densitometer working properly?”

Not

“In your opinion, do I need a densitometer?”

This is another question to which I already know that the answer is: No, probably not, but I like things and I’ve already got one 🙂

Anders

 

[Erik van Straten]

From what I see, is that your negatives are very thin. Maybe this densitometer is for more dense objects or the sensitivity is off.

I have an Epson v600 that has a digital densitometer on board. That instrument is of a great help for scanning. I do not see advantages for analogue printing, but I know that this is not what you ask.

Erik.

 

[Ronald M]

I would say not working. Maybe it is set up for reflection work and it needs to be changed.

No you do not need one unless you run test strips to check developer activity. Also with color neg, check middle grey exposure on red channel.

For scanning, use the histogram. I use a grey scale, black background, a doll with black textured & pleated skirt, white blouse with texture and fine detail. All this must print properly on #2 paper with no burn or dodge. Change exposure to control blacks and developer time to control whites. Poor mans densitometer. This is set up as desired and exposed with studio flash so it works any time.

 

[Glenn2]

The real problem is that you appear to have a reflection densitometer. It’s used for measuring prints and opaque objects.

You need a transmission densitometer, light on one side of the negative, sensor on the other side. Unless the unit you have came with another probe for transparent media I think you are out of luck using it on negatives.

Glenn

 

[PKR]

The real problem is that you appear to have a reflection densitometer. It’s used for measuring prints and opaque objects.

You need a transmission densitometer, light on one side of the negative, sensor on the other side. Unless the unit you have came with another probe for transparent media I think you are out of luck using it on negatives.

Glenn

Reflection densitometers use a mfg supplied control strip for calibration. We did a check of the calculation each morning before running Kodak control strips to test the EP3 line before running any paper through the machine.

Reflection devices are for paper, transmission devices are used for film.

Glenn has it right!

 

[Brassolini]

Thank you for your replies, I appreciate that!

Erik:
I don’t know exactly which zones the thickest I tested in the video were, but the first ones were my zone 1 tests so they ought to be thin.

This however doesn’t explain why one neg registering at approx 1.0 on the low setting wouldn’t jump to 1.0 when switching to the high setting.

Glenn, PKR:
That would explain a lot if true, but I’m finding I hard to believe as the light source is in the base of the unit and the probe arm fits right over the hole where the light shines through. After reading your reply I tested reading prints but that didn’t register anything.

Thanks anyway!

Anders

 

[Brassolini]

Also:
The one-page machine typed instruction sheet specifies that it’s for reading negatives…