Macro Exposure Issue

[Beauty Through a Lens]

I keep noticing that when doing macro photography that my images keep getting extremely overexposed even if it's cloudy. I've been having to fool around and change the exposure from 0 to -2.5 or -3 Is this common or am I doing something wrong? I can upload an example straight from my camera with all the information if needed.

Sorry if this forum is in the wrong place.

[pnodrog]

Are you using the flash?

Yes, do upload an example.

[jcuknz]

When you upload try not to let your editing process strip the EXIF info off ... I believe that posting via sites Facebook et al ] can do this also do not use "Save for the web" [Adobe] .... first reduce the pixel size to between 700 and 1500 across and then use 100% as the file size is not too important when using Tinypix if you have broadband, though if not, reducing the file size to around 100Kb still gives a quality result. My editors show me what is going on in the process of compression ...I hope yours does for you otherwise PaintdotNet. a free download, is very helpful in this direction. [ better than my regular editor ]

This over-exposure when taking close shots with flash was a common complaint in the early days of digital and my solution was to reduce the power of my flash and so I never suffered this problem My attitude was that over-exposure cannot be corrected in editing but under is a simple matter of raising the brightness so if my regular distance flash shots were a bit dark it was no great problem ... though some will argue both over and under are bad for different reasons.

[DanK]

Adrian,

No, it is not common.

In addition to uploading a few photos with exif information--in fact, more important than that--please explain what equipment you were using, whether you were using flash, and the camera and flash settings.

With natural light, metering for macro work is no different from metering for any other photography. The camera is measuring the light entering the camera, and assuming you are using appropriate metering, it should be fine. With flash, most macro photographers use E-TTL flash, meaning that the camera's meter controls the flash to get the right exposure. That's what I do. I use flash exposure compensation on rare occasions, but most of the time, I just set the camera in manual mode and let the metering take care of the flash.

We can get into finer points later, but to start, let folks know how you were shooting.

Dan

[chauncey]

Knowing you gear would help us as well...and your PP skills.

[Beauty Through a Lens]

I'll upload a photo tomorrow, my laptop isn't importuning the photographs correctly.

[DanK]

I'll upload a photo tomorrow, my laptop isn't importuning the photographs correctly.

A description of your equipment and how you metered may be the key. Your exif will show what you got; what we need to be helpful is also how you got it.

[rpcrowe]

I have an older Tamron 90mm f/2.8 AF SP Macro which works great on my Canon 40D. For some reason the exposure is all over the place when shooting with that lens on my 7D, especially with flash. I spoke to a Canon Rep who said "What do you expect from third party lenses?" Not a great answer! A Tamron Rep said " The older Tamron and newer Canon body might not be totally compatible.)

My solution is to continue shooting with the 40D or to shoot Manual exposure and manual flash (like I would with a studio strobe) with my 7D...

[Saorsa]

My flash is smarter than I am. WHen shooting macro I set the camera to maximum sync speed and the aperture to f16 or 22 depending on the camera and lens and my i-TTL flashes will do all the thinking while I get to concentrate on following the damn bug and composition.

[DanK]

My flash is smarter than I am. WHen shooting macro I set the camera to maximum sync speed and the aperture to f16 or 22 depending on the camera and lens and my i-TTL flashes will do all the thinking while I get to concentrate on following the damn bug and composition.

nice shot of a sweat bee. That's pretty much what I do, except mostly at 1/125 and f/13--but the same principle. The TTL metering normally works just fine.

[dasmith232]

And what kind of magnification are you trying to achieve? Extension tubes? How much?

Assuming a semi-automatic mode (like Aperture-priority), I've not ever had exposure issues with any of my Canon bodies and any of my macro and non-macro lenses. When using extension tubes, I've still had no issues with tubes that have the electronic contacts in them. (The tubes are marketed as auto-focus capable, but you shouldn't be trying to use AF with high-mag macro. But you *do* want control of the aperture.) I use Kenko tubes (only) and have never used another brand.

With flash, I have two different ring flash units (one by Yongnuo and the other by Vivitar) that both claim to do E-TTL (in Canon-speak, or iTTL for Nikon) and both overexpose noticeably. The Vivitar is worse and requires about -2 or -3 stops of FEC. The Yongnuo requires only about -1 stop FEC sometimes and is fine with zero on other times.

The first problem that I assume when I hear this is that someone is trying to shoot with a smaller aperture but using non-electronic tubes. The aperture won't close down and hence the over-exposure.

If any of this applies to you, then the EXIF data won't include some of those details (like flash power or extension tubes).

[Geoff F]

Depends a bit on how you are metering, Adrian. Full (evaluative etc) metering coverage can often get fooled by the background so I usually have to set around -1 to -2 exposure compensation. Spot metering is an alternative but that can go wrong if you recompose or your subject moves off the centre point.

If using flash I set the camera manually to suit the scene (typically 1/200 F14 Iso 200) then always use a bit of flash output compensation as required. How much is a matter of experimentation and experience.