Thread subject: Diptera.info :: Flash Macro Photography
Posted by crex on 19-11-2007 08:14
#1
Ok, I start a thread here to continue the discussion from
this thread.
In the Sigma EM-140 DG it is possible to adjust the two lights individually. I think Rafael Estevez mentioned to me that he use this to get a more mellow lighting. I also think he doesn't use the ETTL/TTL, but uses manual settings. When I use ETTL I think the photos are almost always too dark. I'm not sure if this is because of the ringflash or the camera.
Posted by Krister Hall on 28-11-2007 18:48
#2
This is best corrected by the Flash Exposure Compensation (FEC) on the flash, by setting this to +1/3 for normal situations you should get good results. Normally you should use the ETTL, manual mode is not recomended except for studio photography.
Posted by crex on 28-11-2007 19:08
#3
Yeah, I've also tried FEC, but it didn't do much good as the photos still were underexposed. It's a tricky business using flash.
Posted by Krister Hall on 28-11-2007 19:37
#4
Using flash is supposed to be the non tricky business. I can only see two other explanations:
1. The flash is not strong enough, decrease distance or open up the aparture to test.
2. If you are not softening the flash enough you will get small parts that gets overexposed and when the camera measures the ligth it will compensate for this. Then the rest of the image will be underexposed compared to those highlights.
I?m using E-TTL all the time and do not experience those problems.
/Krister
Posted by miked on 24-01-2008 20:49
#5
Are you using canon camera? I have used a variety of canon cameras with nearly all their flash units over many years and almost all combinations can give under-exposure, sometimes to an extreme degree. It is a 'known issue' and many people have tried over the years to get canon to sort it out but with limited success. the last time i sent a camera/flash combination to the canon repair people they said everthing was working within normal parameters "but you may want to try using exposure compensation", i.e. they knew full well that their system sometimes does not work properly.
Having said all of this, the current canon setup I have (400d+mt24+sigma180mm) is working more or less ok most of the time, it does still have its off days where it will require up to +2 stops for no apparent reason but can live with this on digital so long as the insect has not vanished!