Help Please :I am a bit confused

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ujjwaldey8165

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Ujjwal
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I used 4 cameras in the last month or so : Voigtlander (Vitomatic); Contaflex, Rollei 35 and Yashica FXD. When I compared the exposure meter reading, all the four were different (for the same light condition). Indeed, the Conta and the Vito were 2.5 stops apart. Yet they all produce perfectly acceptable results. I used the same film (Kodak 400 ASA) and did no compensation to any of the readings. I did D&P at Tesco. The shots were simple stright forward shots of family, gardens etc


So what did the trick :

(a) Can these films accept so much exposure latitude; or
(b) Do the scanner/printer auto correct for under/over exposure; or
(c) something else, that I haven't figured

Also, I was thinking of buying a used exposure meter to calibrate the cameras. Is it worth it (i.e would it improve the exposure of my shots). Or would this simply add to the confusion; as the meter may not be calibrated correctly.

Is there a common and easy way of calibrating the camera meters?

Your opinions and advice please

Ujjwal
 
B/W, print or slide film ?
Are you looking at the negs or the prints ?
The prints should look fairly similar because the negs are scanned, auto exposed using software and then printed.
Tesco want you to have nice prints, they don't want to give you back prints that come directly from badly exposed negs.
B/W films are very forgiving, colour neg has a bit of latitude, slide is tight.
I'd say if the cameras are exposing correctly, and you can only tell that by looking at the negs on a light table, they don't need calibrating, I don't even know if you can calibrate them other than to use exposure bias control if they have it.
Slide film is a good test.
 
Thanks Joxby.

They are colour prints.

I thought that the exposure is correct merely by looking at the prints. i.e the prints looked properly exposed. I would not be able to tell anything from looking at the negative.

So as I understand : the negatives are autocorrected prior to printing. So, even if the camera is exposing wrong, the D&P machine is doing the correction. So; is there a limit of how much the exposure can be off before it cant be corrected at all.

I was thinking of calibrating using the ASA setting ( i.e change the ASA setting to the point there the exposure is correct; like its done when modern batteries are used as a replacement for old mercury batteries)
 
ujjwaldey8165 said:
Thanks Joxby.

They are colour prints.

I thought that the exposure is correct merely by looking at the prints. i.e the prints looked properly exposed. I would not be able to tell anything from looking at the negative.

So as I understand : the negatives are autocorrected prior to printing. So, even if the camera is exposing wrong, the D&P machine is doing the correction. So; is there a limit of how much the exposure can be off before it cant be corrected at all.

I was thinking of calibrating using the ASA setting ( i.e change the ASA setting to the point there the exposure is correct; like its done when modern batteries are used as a replacement for old mercury batteries)
Click to expand...

You'd have to look at the negs through a loupe on a lightbox, and have a rough idea what you were looking at.
The negs at places like Tesco and Asda/Click whatever, are totally automated, the machine corrects badly exposed negs to the amounts defined by average, some will be too far gone one way or the other, those are the ones you don't get back as prints, though the neg will still exist.
The limits of bad exposure vary from person to person, I don't want anything rough but some peeps are glad to get any old rubbish.
I think you're gonna have to prove that the meters are out, and by how far, before making adjustments.
 
Thanks again.

My plan was to buy a used exposure meter and ( assuming that the meter is giving correct reading) use it to calibrate the cameras by changing the ASA setting.

Of course the flaw in my cunning plan is the exposure meter may not be accurate in the first place.


The other possibility is to use a modern camera ( such as my F65) to be the reference meter.

The rough and ready way would be to use the sunny 16 rule.

But then, if the D&P machines autocorrect anyways, I guess its not worth fussing over the exposure inaccuracy.

BTW : does Jessops etc also autocorrect ( or do I need to specify that they do?) I noticed that Jessops offer hand correcting facilities. Is it better than auto correction, or is it another marketing ploy

Sorry for so many questions; I am aware I am using a few very old cameras (simply because thats the only way I can afford Zeiss or Leica lens) and want to make sure some thing as stupid as a wrong exposure meter undo the efforts of the good lenses.
 
S'ok, I saw it coming...:D...how are you going to prove the meter is inaccurate ?

Well, I dunno, you could use a camera you know to be accurate like the f65.

I was going to say, shoot some slide film, get them scanned to disc by Tesco or whoever, who will ofcourse adjust them and we'll see what your hit rate is by numbers.
Post them here, we have some verrrrry particular scan watchers who may be able to see or estimate just how much adjustment has been made to them.

If your hit rate is high, and we can't tell they've been adjusted from a very naff exposure.........heck, it doesn't even matter :lol:

All the high street labs adjust to their own taste, if you want control you need to scan them yourself.
 
Thanks Joxby.

I was getting a bit worked up in my mind over this issue the last few days; but the reality possibly is : If the prints are coming out OK, it possibly does not matter too much. Not to me anyways; I am just begining to learn the craft; and lack of 'perfect exposure' is possibly the least of my troubles.

Thing is, I just went through a book called "Perfect Exposure", and that kind of focussed my mind on this aspect. Goes on to show how dangerous it is to start reading up random books rather than going out and shhoting a few rolls, especially for a beginner.
 
In fact, if you sent the films to a pro lab, they'd still be corrected for any exposure inaccuracy, but manually, by someone who knows what he's doing, that's what you pay for.
 
I once sold a guy a Pentax LX body, and he was back the following day, looking pale from lack of sleep, complaining that he was getting a huge indicated exposure difference between the LX and his other camera body and wanting a refund.

I told him I was happy to give him a refund, but the problem was he was taking the readings from the LX with no film in the camera, and the the LX actually meters off the film during the exposure. With no film in the camera, the meter was reading off the black film pressure plate.

He wasn't happy till we we took it round to my tech guy who measured the exposures and found them bang on.
 
Ah..thanks CT. Thats a new one. I was measuring some with film in it, and some without. Maybe that could explain some of problem.

Do you know the measuring system of any of the cameras I mentioned in my first post
 
Well I'd doubt any of those cameras you mention, were that advanced, in fact, I'd think most of them had the old selenium cell type window on the outside of the camera?

I doubt it matters about film being loaded tbh, but I think you need to be careful to make sure you do the tests all at the same time under pretty stable lighting to be sure.

A stop difference between these cameras is nothing unusual at all and as long as they're producing decent results you're probably worrying too much, but I'd probably be the same. :D

A rule of thumb test for neg exposure is to place the neg emulsion side down on a sheet of newsprint and you should just be able to read the print through the densest parts of the neg. Don't use a thin night exposure neg obviously.

You should be able to calibrate a decent hand held meter, but I think you'd be struggling with these cameras, even if you could find someone to do it.

Once you're happy that your meter is accurate, the easiest thing to do is adjust the camera ISO (sorry ASA :D ) as you've suggested.
 
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