@Cindy-Clicks wrote:
These two images were both taken with the 6D ev metering, f/13, ISO 800. They were taken seconds apart. The one on the left was 1/125 sec. and the one on the right was 1/25 sec. Why would there be such inconsistancy under the exact same conditions?
Let me guess...
Do you have Auto ISO on?
"These two images were both taken with the 6D ev metering, f/13, ISO 800."
That's completely impossible. Either something changed in the lighting from one shot to the other... Or, if lighting remained steady, one of the settings changed without you realizing it... Or, if lighting remained the same and the exposures were that different, the images were "corrected" in post-processing.
Using Evaluative Metering and any auto exposure mode in a situation like this can result in variances... due to the extremely dark background and bright subject. But in order for exposure to appear idential in two images - unless the lighting conditions changed or image brightness was corrected in post-processing - no single exposure factor can be changed without compensating for it by adjusting another exposure factore.
Also note that the difference between 1/125 and 1/25 isn't anywhere near 7 stops. It's actually only a difference of slightly more than 2 stops. (1/125 > 1/60 is one stop.... 1/60 > 1/30 is another stop... 1/25 is one third stop less than 1/30... so the exact differece is 2.33 stops).
Macro/close-up makes for very shallow depth of field. To increase depth of field it's often necessary to stop lenses down to smaller apertures... which in turn means either slower shutter speeds or higher ISOs or adding some additional light with a flash or some appropriate combination of the three.
If you want to keep ISOs moderately low, you'll have to deal with slower shutter speeds either by using flash or by using a tripod... or at least a monopod. A lot of macro shooting is done from a tripod or monopod, due to the slower shutter speeds that are often needed.
Macro flash is something you may want to look into, if you want to do a lot of handheld work. There are special, dedicated macro flashes (Canon MT-24 EX Twin Lite and MR-24 EX Ring Lite). For the type of subject you're shooting, I'd use a twin light. Or, there are ways to use a single, standard flash too, Just diffuse it so it won't overpower a close subject (there are diffuser accessories, but I often just use two or three layers of white gauze bandage, held in place over the flash head with a rubber band). Put the standard flash on an off-camera shoe cord and handhold it to have lots of flexibility where it's located.
One of the key advantages of the two Canon 100mm macro lenses. Unlike most (maybe all) other macro lenses in the 90 to 105mm focal length range, the Canon 100mm macro lenses can optionally be fitted with a tripod mounting ring. The 100/2.8 USM uses Tripod Ring B (which it shares with a few other lenses, including the MP-E 65mm ultra high magnification macro lens and the 180/3.5L macro lens) and the 100/2.8L IS USM uses Tripod Ring D.
Previous responses are correct... Exposure is exposure, regardless of sensor format.
But for various reasons, compared to a crop sensor camera a full frame camera generally can be used at somewhat higher ISOs before image noise becomes a problem. And, because there's less magnification needed to make a print of any given size from a full frame image, smaller apertures can be used before diffraction becomes an issue.
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Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7D(x2), 50D(x3), some other cameras, various lenses & accessories
FLICKR & EXPOSUREMANAGER
"I have heard that there is now a lens that is less than f/1"
Canon made a 50mm f1 lens. It is no longer made and has become ledgendary.
It is very expensive on the used market. Does this question have something to do with your issue or are you just commenting?
Saving as a jpg does not remove the exif. But saving for the web does (or I should say can.).
