More on my underexposed M2 slides; meter problems?

[Ronald_H]

Got my first roll of slides back, shot with my 'new' M2. Most of them were severly underexposed. Used a Gossen Digiflash handheld meter in reflective mode. Battery was fresh.

I also had my Nikon FE with me, this generally gave readings about a stop lower than the Gossen. I elaborated this further and found out that the Gossen readings differ quite a bit from the Nikon in almost all cases. I realize that the metering pattern is different, but this much difference? It almost looks like the Gossen does not give an average reading, but a highlight reading.
But even when pointing it at the ground the readings are too high.

I shots slides with FM and FE's regularly, and they were all well exposed. To be honest, the slides from the M2 look so dark that it it is probaly more difference than one stop, so the shutter of the M2 is probably off too.
So, what's up? Is it me being silly, or is my meter not good? Is it too much to expect that a handheld meter would give me half decent slides?

 

[kipkeston]

Take it out on a sunny day and see what happens

 

[ChrisN]

Every meter will be different, and some are several stops out. Test your meter with an 18% grey card (get one from your camera shop) in full sunlight - you should get 1/100 f/16 @100 iso. Get close enough so the meter is reading only the card surface.

I tested my new Pentax Spotmeter this way - spot on. My Gossen Profisix is one stop out, but it easy to compensate.

 

[furcafe]

Aside from variations in sensitivity between manufacturer, the metering pattern is probably different from that in your SLRs.

IIRC, the Digisix/Digiflash's coverage in reflective mode is close to that of a 90mm lens (in 35mm format), so you have to be careful where you point the meter. If the Gossen was giving you a highlight reading, you may have been aiming it @ highlights.

I've used the Digisix & Digiflash for years & never had a problem. Is it possible your Digiflash is stuck in flash mode?

Did you try using it in incident mode?

Got my first roll of slides back, shot with my 'new' M2. Most of them were severly underexposed. Used a Gossen Digiflash handheld meter in reflective mode. Battery was fresh.

I also had my Nikon FE with me, this generally gave readings about a stop lower than the Gossen. I elaborated this further and found out that the Gossen readings differ quite a bit from the Nikon in almost all cases. I realize that the metering pattern is different, but this much difference? It almost looks like the Gossen does not give an average reading, but a highlight reading.
But even when pointing it at the ground the readings are too high.

 

[Bill58]

My used Gossen Luna Pro was one f stop off all the way across the range and Hollywood Meter CLA'd and adjusted it. It's spot on (pun intended) now if I can remember to keep the dome out of the way!!!

 

[spyder2000]

Yes, compare the meters in direct sunlight off of a large expanse of grass or concrete. Enough so so that the metering patterns will average out the differences between themselves. See how they compare and then compensate to bring them together.

In this case it won't matter if the average reflectance is 18% (or 75% for that matter) as what you are seeking is a comparison.

You may also want to compare shutter speeds by recording identical scenes simultaneously at identical settings to see if there is a noticeable discrepancy between the two shutter timings. This is less useful because of the tolerance allowed for shutter speeds (and more tolerance at the higher speeds) but may further assist you in refining your exposure.

 

[Rob-F]

Ronald, I think your Gossen meter is off. See my comments over on the photo.net Leica page.

 

[Sparrow]

You can test the shutter speeds with a TV tube, shoot each speed from 1/50 all at f2 or f2.8

I probably should have turned the TVs brightness down but you should get something like this

 

[Sparrow]

1/1000 = 14.4 lines, or 5% of the screen
1/500 = 29 lines, or 10%
1/250 = 58 lines, or 20%
1/125 = 115 lines, or 40%
1/60 = 240 lines, or 80%
1/50 = 288 lines, or 100%

 

[Ronald_H]

Don't you think it all slightly ironic that the fault lies in all likelihood with a two year old digital meter, instead of a 42 year old mechanical camera?

 

[ferider]

1) one stop should not give you severe problems in the final negative. I am guessing there is another issue with your camera. Use Stewart's method to check the camera's exposure times.
2) I don't think your Gossen meter is "wrong", just different from your Nikon. One might be calibrated to slide film, one to negatives. A digital sensor has other exposure requirements than slide film, which is again different from different negative films, etc.

Remember that many negative films benefit from half or a full stop pull. Learn the combo (film + meter), and how to correct it according to the final outcome you want.

 

[rtphotos]

Hi Ronald,

I think what some of us are trying to convey is that you may want to be more systematic and test your camera and meter independently. Right now you have too many variables going on at the same time.

In other words, first determine if your camera shutter speeds OR your light meter is off.

Test your camera's range of shutter speeds by running a roll of film on a static object. Then do a separate test (no need for the M2 here) comparing exposure readings of your Gossen and your FE.

rt 🙂

 

[Ronald_H]

Well, I am a tester by profession, so I should know something about isolating variables. The point is you would EXPECT an old, relatively cheap and battered M2 to be off. Not so with a digital Gossen meter.

The Gossen is a stop off in most cases, compared to my FE and D200. Also when I read off a white wall, where metering pattern is irrelevant. The meter is definitly wrong. More confirmation is that I got some negs back today, shot in a museum with my Canonet. I used the Gossen there in INCIDENT mode. You guessed it, underexposure.

The trick with the TV screen I haven't tried yet, will do that today. Slightly off-topic: Also found an ancient Gossen Lunasix on eBay for 25 euros and that will arrive this week. Also bought 9 rolls of film for 20 euros.

Analog photography, isn't it fun?

 

[Sparrow]

Not all meters are set the same by the manufacturer, if I recall correctly there is something called the K-factor which, as I understand it, allows you to compensate if the meter has been calibrated to anything other than 18% grey, but I’m not sure you need to go to that level of accuracy.

See if the meter reads Sunny f16 correctly, the back of your hand should read f16 at 1/film-speed in full sunlight, if you have a bit of a tan like I normally have, a stop lighter for the palm.

 

[rtphotos]

Well, I am a tester by profession, so I should know something about isolating variables. The point is you would EXPECT an old, relatively cheap and battered M2 to be off. Not so with a digital Gossen meter.

Hope you didn't take my suggestion as an insult. It wasn't meant as one.

Without knowing the background history of camera or meter, I'd not assume either to be working perfectly, nor one more likely to be working properly....

Good luck on your M2 and Gossen. I hope you get it all sorted out. Yes, I agree that analog photography can be FUN!

rt 🙂

 

[payasam]

If your meter is off by one stop and your slides are grossly under-exposed, it may be that the M2's shutter too is off. Age is only one factor which can lead machines and instruments to malfunction.

 

[Ronald_H]

Well gentlemen, the mystery has been solved!

The ugly truth is that BOTH the meter and the camera were off. This morning my M2 got into the hands of a respected Leica repairman. He assured me that the speeds were off.

What's more, he was so kind to have me check my meter against the calibrated light source on his test bench.

'Look, your meter isn't off at all, it reads 11 and 15 Ev spot on!'

'Well yes, nice to hear that, but I dialed in minus 1 1/3th of a stop compensation this morning...'

😀

CLA will take about a week, and then... I'm going to roam the streets! The FP4+ and Tri-X in my freezer shiver in anticipation!