Light Meter Troubleshooting - extremely low readings

[Kevin Marshall]

I just snagged an L-398M off of ebay. When checking/testing the meter, I've been getting really low readings, especially when compared to spot metering off my gray card. For example - putting the meter about 6 inches away from 3 26W daylight CFLs (about 100W tungsten equivalent each) gave me 15fc - about f/2+2/3 at 800ASA according to the meter. Spot metering the gray card with a canon DSLR and Cinemeter gave me around f/11. Also, checking outside today - fairly overcast at around 2pm - the l-398 gave me 40fc, or around an f/4.

First - no, the High slide isn't in. I tried working the zero adjust, but it seemed to be zeroed okay. I'm just wondering if anyone knows any other maintenance/cleaning I could try before I call it a dud and start emailing the seller.

I've read that the selenium cells in these had the possibility of losing sensitivity over time, but more research seemed to show that this was on the order of a tenth of a stop or so over several years of use. This unit looks pristine - not a single scratch/dent/wear mark/etc on it. It looks like it's been barely - if ever - used.

I'd greatly appreciate any insight.


EDIT: Just went to compare to my gray card again - the incident meter is showing about 5fc (~f/1.4) outside, with the gray card spot metering at f/32....

 

[Michael Notar]

i always calibrate a new meter to my old one since i did exposure tests with the older sekonic one (tests done about 7 years ago). i use the 0 adjust to match them. i had a 558 i think and the spot meter (reading a grey card) had to majorly adjusted to the incident by like a 1.5 stops. so there is no correct for a meter. i dont believe a brand new latest and greatest swanky meter is any better than an older modern one. i always calibrate my incident meter to sunny 16 readings under appropriate light.

 

[Kevin Marshall]

Unfortunately, even at the maximum it would let me adjust it to, the meter is still reading at an f/2.8 where my gray card gives f/8. Note also if I take off the dome, and cover the port with duve, I will also get an f/2.8 reading at this calibration, which is obviously incorrect.

 

[ericyoung]

Silly question - is the battery low?

 

[Christopher Mills]

L-398m model does not use a battery.
Not sure what would cause the symptom you describe

http://www.sekonic.com/support/faqs/sekonic-l-398a.aspx

I note that thye say that storage in a humid climate may shorten selenium lifespan to 10 years, though many 40+ year old l398ms work fine.

I used to consider these a very safe meter to buy used.. perhaps I will reconsider.. as they are very inexpensive new.

 

[Kemalettin Sert]

silly question whats the lowest t stop can 758cine can measure?

 

[Kevin Marshall]

L-398m model does not use a battery.
Not sure what would cause the symptom you describe

http://www.sekonic.com/support/faqs/sekonic-l-398a.aspx

I note that thye say that storage in a humid climate may shorten selenium lifespan to 10 years, though many 40+ year old l398ms work fine.

I used to consider these a very safe meter to buy used.. perhaps I will reconsider.. as they are very inexpensive new.

This is what had me puzzled. Everything on the unit, even the lanyard and the case, look pristine. Though I did make one error - on second look, it's not a L-398M, but the slightly older L-398 - meaning it's from somewhere between 1976-1988. Either way, the original owner apparently took very good care of this thing for 25+ years, and I find it odd that it would be off by 6 stops or so. Not to mention I remember my school having several light meters from the Norwood family - all of which still work fine after untold years of near-daily use by students.

 

[Peter Borosh]

Kevin,

Correct me I'm wrong but the Selenium photocell does have a shelf life of a few decades. I've recently purchased an old "new" stock Weston Master V. Unfortunately the photocell was dead even though it was unused. I was able to get the photocell replaced and it works as new.

 

[Kevin Marshall]

Yeah, my worry is that the selenium cell is basically dead. Sekonic's generalized repair form gave estimates on the L-398 as Minor Repair: $85, Major Repair: $125. I'm not sure which category cell replacement would fall under, especially since you can't legally make selenium cells any more. Either way, it's around half the cost of a brand new L-398A, which may be my next option.

 

[Peter Borosh]

Kevin,

I got the Weston repaired at Quality Light Metric. They quoted the price over the phone without seeing the meter and they did a quick turn over. They maybe more competitive than Sekonic in pricing.

Quality Light Metric
(323) 467-2265
7095 Hollywood Blvd Ste 550, Los Angeles, CA

 

[Kevin Marshall]

Thanks Peter - I've read some good things about them. The ebay seller I bought from doesn't accept returns, so QLM may be the best way for me to salvage the situation.

 

[Kemalettin Sert]

ı uploaded sekonic camera profiles on my 758Cine and still it doesnt match with Red Epic and 5D mark III.i measure 1.2 Fstop on Sekonic and 1.4F on 5D mark III.