Fabrice2
Established
I've read yesterday on a French forum, a guy with a canonet problem, in A mode, the needle shows 1,7 and the lens open to 2,8.
I checked one of my canonets and i got exactly the same problem, i noticed that this GIII QL17 is a different type from my other ones, it's written on the back "made in taiwan R.O.C" and there's a piece of plastic in the back, on my other GIII the piece is in iron.
May be this problem happens only with only those models??
There is a kind of delay (or decalage?sorry for my bad english) between the apertures and the meter, the meter is good but the aperture is wrong.When the needle say F4 it opens to 5.6, F11< F16, F16<~F16,2
The problem occurs only in A mode.
I though it was a meter problem, but the meter is accurate according to my leningrad 8.
There's not a lot of canonet specialist in France, so i ask for your help guys.
Got an idea?
I checked one of my canonets and i got exactly the same problem, i noticed that this GIII QL17 is a different type from my other ones, it's written on the back "made in taiwan R.O.C" and there's a piece of plastic in the back, on my other GIII the piece is in iron.
May be this problem happens only with only those models??
There is a kind of delay (or decalage?sorry for my bad english) between the apertures and the meter, the meter is good but the aperture is wrong.When the needle say F4 it opens to 5.6, F11< F16, F16<~F16,2
The problem occurs only in A mode.
I though it was a meter problem, but the meter is accurate according to my leningrad 8.
There's not a lot of canonet specialist in France, so i ask for your help guys.
Got an idea?
greyhoundman
Well-known
First. What battery are you using?
Second. Check it against a different meter.
Three. Just how are you determining that the aperture is wrong?
Second. Check it against a different meter.
Three. Just how are you determining that the aperture is wrong?
greyhoundman
Well-known
Huh?..........
Fabrice2
Established
1/i use a PX625 and i also try a wein air cell with a ring adapter.
2/The other metter i have is the one from an olympus xa.
3/i set the camera in B mode, point the camera to a bright object, when the needle is showing F4, i shoot, and watch the lens, i go on manual, put F4 and rewind,the blades opens to the real F4.
The needle shows the good aperture, but the lens wont open enough.
2/The other metter i have is the one from an olympus xa.
3/i set the camera in B mode, point the camera to a bright object, when the needle is showing F4, i shoot, and watch the lens, i go on manual, put F4 and rewind,the blades opens to the real F4.
The needle shows the good aperture, but the lens wont open enough.
greyhoundman
Well-known
Wrong on all counts.
You can't test a meter in B mode.
You can't test a meter in B mode.
greyhoundman
Well-known
You have to be in manual to get proper B operation. The aperture is designed to use manual in B mode.
And the meter does not work in manual mode.
And the meter does not work in manual mode.
Fabrice2
Established
The meter works in B pose in mode A, maybe it's because of the problem?
The needle moves in B.
The needle moves in B.
greyhoundman
Well-known
Set the shutter speed to 1/500, 400iso in bright sunlight in A mode. Also test at 100, 200 iso in A mode.
B is for bulb, you know like dim bulb. You are not going to be shooting B speed in A mode.
B is for bulb, you know like dim bulb. You are not going to be shooting B speed in A mode.
Fabrice2
Established
Yes i know the meter doesn't work in manual mode.
To resume, If i want to shoot at 1,7 in Automatic mode, using the needle at 1,7 the lens won't open to 1,7 but ~2,8, in any speed, even B.
To resume, If i want to shoot at 1,7 in Automatic mode, using the needle at 1,7 the lens won't open to 1,7 but ~2,8, in any speed, even B.
Fabrice2
Established
OK i'll do it, but now impossible, here it's night and rainy
greyhoundman
Well-known
If you are using a 625 alkaline battery, it will cause the meter to read high.
In manual, does the aperture open all the way to 1.7?
In manual, does the aperture open all the way to 1.7?
Fabrice2
Established
In manual everything works perfect.
I tried with a PX625 and the wein air A675, no real differences with the meter.
But the lens should do what the meter says, even if the meter reads high,isn't it?
The best way to use the camera is to read the meter in A mode and swith to manual and set the aperure to shoot.
I tried with a PX625 and the wein air A675, no real differences with the meter.
But the lens should do what the meter says, even if the meter reads high,isn't it?
The best way to use the camera is to read the meter in A mode and swith to manual and set the aperure to shoot.
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greyhoundman
Well-known
If the meter is showing 2.8 in A mode, but the lens won't stop down that far. It sounds like a backyard meter adjustment was made.
The needle was bent to say what they wanted. It is a trap needle meter system.
If it syas one thing and does another, time for a fix.
The needle was bent to say what they wanted. It is a trap needle meter system.
If it syas one thing and does another, time for a fix.
Fabrice2
Established
i 've checked the needle yesterday, it's straight.
and when it goes in the red zone i can't shoot.
i should have red zone then f1.7, i have red zone then f2.8(the arrow shows 1.7).
They used another method i suppose.The meter screw??
Is it the good way to calibrate the meter to the new batteries?
Because there's a kind of regularity between the needle/lens.
and when it goes in the red zone i can't shoot.
i should have red zone then f1.7, i have red zone then f2.8(the arrow shows 1.7).
They used another method i suppose.The meter screw??
Is it the good way to calibrate the meter to the new batteries?
Because there's a kind of regularity between the needle/lens.
greyhoundman
Well-known
There is no screw for adjusting the meter.
I don't have your camera in front of me. I can't tell what may be hacked on it.
The only mechanical way to screw up a meter is to start bending things.
But I know that unless a meter (handheld) has been verified against a known good source, it is worse than no meter.
If the meter is reading 2.8 and it is not at that aperture, something is bent. It is not an electrical problem.
I don't have your camera in front of me. I can't tell what may be hacked on it.
The only mechanical way to screw up a meter is to start bending things.
But I know that unless a meter (handheld) has been verified against a known good source, it is worse than no meter.
If the meter is reading 2.8 and it is not at that aperture, something is bent. It is not an electrical problem.
greyhoundman
Well-known
I don't normally blow my own horn. But right now there are at least 6 people on the board who are using GIII's I rebuilt. Try the search function sometime.
outfitter
Well-known
One little oddity I noticed: in A mode you can't see the iris stop down until you fire the camera; in manual mode if you don't re-cock the camera the iris will stop down as you go to smaller f-stops but if you go to a higher f-stops afterwards the iris wont open up again. Could this be affecting your tests? In other words before setting the f-stop in manual mode re-cock the camera otherwise you may not get a true picture. Of course it wouldn't hurt to take pictures in both manual and A mode and compare the results.
Spyderman
Well-known
My canonet does a similar thing: the aperture readout in VF is ok compared to a known good handheld meter, but in A mode the aperture stops down more than that.
The reason is, that someone recalibrated the meter to read good with alkaline battery. But there is more voltage 1.5 vs. 1.35 and the higher voltage causes an electromagnet in the diaphragm stop-down mechanism to set smaller (higher f-stop number) actual aperture.
Only way to overcome this is to use manual mode. Or recalibrate the meter back and solder a diode in series to the battery to drop the supply voltage.
The reason is, that someone recalibrated the meter to read good with alkaline battery. But there is more voltage 1.5 vs. 1.35 and the higher voltage causes an electromagnet in the diaphragm stop-down mechanism to set smaller (higher f-stop number) actual aperture.
Only way to overcome this is to use manual mode. Or recalibrate the meter back and solder a diode in series to the battery to drop the supply voltage.
greyhoundman
Well-known
There is no electromagnet stop down system. It is a purely mechanical trap needle system. It runs on springs and the meter needle.
Kat
Well-known
Hmm, this seems to be the same problem with my Canonet. Meter reads fine compared to other camera meters. However, in Auto, when it reads 1.7, apperture in reality won't fully open as it would in 1.7 manual mode. Otherwise, it works normally. The camera is with the repair guy for lens cleaning, I'll have to check again and verify if I have the problem when it gets back.