new micro 4/3 camera and goes underwater

Please register or login

Welcome to ScubaBoard, the world's largest scuba diving community. Registration is not required to read the forums, but we encourage you to join. Joining has its benefits and enables you to participate in the discussions.

Benefits of registering include

  • Ability to post and comment on topics and discussions.
  • A Free photo gallery to share your dive photos with the world.
  • You can make this box go away

Joining is quick and easy. Log in or Register now!

m4/3 is like a dslr. If you chose Aperture, the camera correct exposure with shutter speed and iso. But iso first.

In full auto it goes with big aperture first then iso then shutter speed.
 
The sharpest point of any lens in general is between f9-f20, so this is where you really want to be when shooting macro at 1:1, there are no true macro 1:1 with a aperture bigger then 2.8.

I'm not realy sure that this is true, at least not for the Oly 50mm 4/3 macro lens.
Its sharpness is above the "Nyquist frequency" from F2.2 to F8. With the sweet spot at F4. This lens is prob still producing excelent results down to an aperature of F13 but after that it starts to show. At least in studio tests ;-)
Olympus Zuiko Digital 50mm F2.0 Macro Lens Review: 3. Test results: Digital Photography Review

At F20 you have half the sharpness compared to when shooting at F4.

The reason for people to shoot mostly at v high F-stops with macro lenses is that the DOF is to shallow to be usefull if doing close up subjects like nudis and anemone shrimps with an F-stop like F4.
 
for uw macro, you really can not hand hold for the higher aperture. But for topside macro with a tripod. You would want the higher f stop.
 
If you can't hand hold at high aperatures, then you need to buy a more powerfull strobe! Or use a higher iso setting....
 
For me that is just way to bulky to dive with. I dive more to visit nature, rather then for a underwater shooting day. I still dive with a compact point and shoot and simple housing.
 
I'm not realy sure that this is true, at least not for the Oly 50mm 4/3 macro lens.
Its sharpness is above the "Nyquist frequency" from F2.2 to F8. With the sweet spot at F4. This lens is prob still producing excelent results down to an aperature of F13 but after that it starts to show. At least in studio tests ;-)
Olympus Zuiko Digital 50mm F2.0 Macro Lens Review: 3. Test results: Digital Photography Review

At F20 you have half the sharpness compared to when shooting at F4.

The reason for people to shoot mostly at v high F-stops with macro lenses is that the DOF is to shallow to be usefull if doing close up subjects like nudis and anemone shrimps with an F-stop like F4.

I agree that optimal aperture for sharpness varies from lens to lens. Most lens are sharpest a few stops above wide open. The issue then becomes depth of field, so optimal for a large depth of field might be F8-f13 but you will sacrafice end-to-end sharpness. F4 on this 50mm is the best for end-to-end sharpness.
Here is a good sight if the lens you are interested has been tested. Click on the blur index and then you can dynamically scroll through the F-stops to see the impact on image sharpness. Notice that at F4, it is the best.

Olympus Lens: Primes - Olympus 50mm f/2 Zuiko Digital Macro (Tested) - SLRgear.com!

Below is the link to the 4/3rds 14-42 where you can look at sharpness over the zoom range and f-stops (remember to click on the blur index chart to make it interactive). Not too bad Olympus!
Olympus Lens: Zooms - Olympus 14-42mm f/3.5-5.6 ED M.Zuiko Digital (Tested) - SLRgear.com!
 
I agree that optimal aperture for sharpness varies from

Below is the link to the 4/3rds 14-42 where you can look at sharpness over the zoom range and f-stops (remember to click on the blur index chart to make it interactive). Not too bad Olympus!
Olympus Lens: Zooms - Olympus 14-42mm f/3.5-5.6 ED M.Zuiko Digital (Tested) - SLRgear.com!

I think this sort of review of the 14-42 shows the limits of studio tests.

There is an issue with the 14-42 lens where the vibrations from the E-P1 shutter at 1/100 to 1/200 cause the internal focusing mechanism to rattle around and lose focus, especially with the original firmware. If you put the camera on a tripod with a secure mount, you change the natural frequency of the camera and this problem goes away, so it doesn't show up in studio tests, just in handheld shots.

I've found that my E-P1 takes much sharper photos with third party lenses than with the Olympus kit zoom, even though the studio MTF tests show that the 14-42 is a sharp lens. Heck, even the 8mm four-thirds lens with the MMF-1 adapter looks sharper than the 14-42, and that's a fisheye lens.
 
One thing that these bench tests agree on is that the Olympus 50 mm macro is one of the sharpest macro lenses at any price. I use the lens all the time for underwater work and add the 1.4 & 2 X tele converters plus a +6.5 diopter. I us the lens in a range between F/14 to F/22 and in the field even with the added tele converters the images are very sharp.

Regarding hand holding the macro lens underwater at F/22 and beyond what some are failing to take into consideration is that most macro exposures are 100% flash exposures. At ISO 100, !/250th sec shutter speed and F/22 while the shutter may remain open for 1/250th or 1/160th (what ever your cameras top sync speed) the main light source, I.E. strobe flash lasts only about 1/1000th of a second freezing the motion of the subject. The idea that a tripod would need to be used for U/W macro is false unless you rely on AV light for the bulk of the exposure as you would with most video shots.

The attached images were all shot hand held at F/14 and well above using ISO 100 at 1/250th. Two use the 2 X tele converter in addition. All taken with Olympus E-3 or E-620.

More images in my E-620 review.

FourThirdsPhoto.com | Olympus E-620 and PT-E06 Housing

Phil Rudin
 

Attachments

  • -8054474-1.jpg
    -8054474-1.jpg
    355.4 KB · Views: 70
  • -8311292.jpg
    -8311292.jpg
    343.9 KB · Views: 70
  • -8311331.jpg
    -8311331.jpg
    80.1 KB · Views: 73
  • -9025591.jpg
    -9025591.jpg
    68.1 KB · Views: 74
If you can't hand hold at high aperatures, then you need to buy a more powerfull strobe! Or use a higher iso setting....

Like Phil said, sometimes a lower ISO setting is better to get rid of motion blur from hand holding, because a higher percentage of light will come from the strobe, and you'll get a Doc Edgerton style freeze frame.
 

Back
Top Bottom