Thenks for the info everyone. One more question, I have a set of extension tubes on the way, how does the extension affect metering and exposure?
If you are using an external meter, it does require additional exposure compensation to use extension tubes. If you are using an in-camera meter, extension tubes simply cause less light to reach the meter, just as less light reaches the film with the tubes, so while the exposure will change from what it would be without the tubes. The effect of the tubes is taken into account by the meter, so no additional adjustment is necessary.
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