SEI Exposure Photometer

[NormaN]

I have a meter like this. It works as far as I can understand, except one filter disc (color matching disc?) is probably blocked. I tried it out a bit, fascinating but too difficult for me. That's why I'm sticking with my Seconic L758. I have 2 PDFs that I would like to attach here, but the files are too big. In one of these documents there is also a kind of repair manual.

If someone is interested I could send it by mail

I also share a link

http://www.robertsuomala.com/5.html

[ic-racer]

What do you hope to do with it?

Repair.

[tfb]

I have one of these which I spent some time understanding. I hope that this is still useful (I only just made an account)

There are at least several variants: older ones (mine is) use BSI for the film speed: BSI is DIN + 10.

You need to make sure it is calibrated using the galvanometer on the top, and this can be a saga of dodgy contacts. Once you've done that you need to set film speed with the knurled wheel at the bottom. Beware that the manual expects you to meter in a very specific way: for negative film (black dot for film speed) you're expected to meter the darkest point you care about and for reversal film (white dot) the brightest point. If you want to meter in between you need to offset the film speed.

Then there is a little wheel at the front of it which has three coloured dots on: blue, white and red. These put filters in place, blue being darkest and red probably being 'no filter at all'. The wheel at the back changes the spot colour to be right for incandescent light.

OK, so with the darkest filter you can manage make the spot vanish. Now, the aperture can be read upwards to one of the three scales. The three scales correspond to the three filter colours. When the meter was new the scales were coloured blue, white and red. On mine the blue one still is blue but the red background is barely detectable. The scale you read depends on the filter setting: blue dot means blue scale and so on. Blue is lowest, white is above it and red is at the top (there are some other scales above that which I forget what they're for).

[Peter Lovett]

I have one of these which I spent some time understanding. I hope that this is still useful (I only just made an account)

There are at least several variants: older ones (mine is) use BSI for the film speed: BSI is DIN + 10.

You need to make sure it is calibrated using the galvanometer on the top, and this can be a saga of dodgy contacts. Once you've done that you need to set film speed with the knurled wheel at the bottom. Beware that the manual expects you to meter in a very specific way: for negative film (black dot for film speed) you're expected to meter the darkest point you care about and for reversal film (white dot) the brightest point. If you want to meter in between you need to offset the film speed.

Then there is a little wheel at the front of it which has three coloured dots on: blue, white and red. These put filters in place, blue being darkest and red probably being 'no filter at all'. The wheel at the back changes the spot colour to be right for incandescent light.

OK, so with the darkest filter you can manage make the spot vanish. Now, the aperture can be read upwards to one of the three scales. The three scales correspond to the three filter colours. When the meter was new the scales were coloured blue, white and red. On mine the blue one still is blue but the red background is barely detectable. The scale you read depends on the filter setting: blue dot means blue scale and so on. Blue is lowest, white is above it and red is at the top (there are some other scales above that which I forget what they're for).

Thank you for the information. For the moment any action is on hold as I think the contacts for the galvanometer have gone on holiday. It has become a question of how much more I am prepared to spend for what return?

[mpirie]

While repairing my SEI, i found that using a D cell from a well known brand wouldn't fit.

The meter came with a sleeve for the battery compartment which looks like it's made of shellac. I assume this is an insulator from the meter body, so removing it allowed the battery to slide in. However, the meter still wouldn't work. I removed part of the plastic sleeve on the battery at the positive end as the electrical contact wasn't making it.

Once those mods were made, the meter worked fine. However, the weight puts me off using it!

Mike

[Bill Burk]

I've been using a cheap plastic D to AA battery shell converter with fresh AA battery that's enough to power the light bulb and I shaved off some of the shell to fit in the sleeve.

My understanding is that carbon D batteries came in paper wrappers and you were intended to unwrap the cell and put the core in the sleeve. Alkaline D cells have greater size and thinner wrappers so they can't be easily inserted if at all.

[Bill Burk]

Repair.

Missed your posts here. Are you still looking for a broken SEI ? They turn up on eBay for a good price once in a while. They're "all" broken because the selenium cell is always dead/weak. The filters are often deformed by moisture/age.