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peterbkk

Member Since 25 May 2005
Offline Last Active Aug 25 2014 09:34 PM
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Posts I've Made

In Topic: GH4 - Nauticam Macro Lens/Port Thoughts

25 August 2014 - 09:34 PM

Olympus lenses are not stabilised. This can be a problem at long focal lengths


Very true.

Lack of stabilisation can also be a problem for Close-Up wide-angle shots as the impact of any camera movement is obvious for any very close subjects, even against a wide background.

For underwater video, buffeted by water movement, stabilisation is always important, with the only exception being WA shots where the subject is more than a meter away, in which case, the relative impact of camera movement is much less. With WA shots of fish and people, often the subject is synchronised by the same water movement.

Regards
Peter

In Topic: GH4 - Nauticam Macro Lens/Port Thoughts

20 August 2014 - 11:50 PM

What about fitting the 12-35 in the special Nauticam 12-50 port? It's got a 77mm thread, so I'm assuming it's wider than the 65mm macro.

 

Without the special 12-50mm gear, it's $450--only $150 more than the 65mm macro port. http://www.backscatt.../na-36161.lasso

 

Of course,  it would mean getting the 77mm flip diopeter instead of the 65mm, but if it works with the quality of the 12-35, it might be a good trade-off.

 

Unfortunately I don't have that port to test the combination.


In Topic: GH4 - Nauticam Macro Lens/Port Thoughts

19 August 2014 - 12:20 AM

It is a shame as the 14-42 lens is not that sharp

 

I'm wondering why you'd say that it is not that sharp.  Have you used this lens and seen sharpness issues?

 

Most of the reviews seem to be positive on its optical qualities.  One of the reviewers that I tend to trust (because they do precise bench tests rather than subjective hands-on field tests) says:

 

"Sharpness 

The Panasonic 14-42mm ƒ/3.5-5.6 X is remarkably sharp, and a noticeable improvement over the existing 14-42mm kit lens. Used at its widest focal length setting (14mm) at its widest aperture (ƒ/3.5) the lens provides excellent results for sharpness in the center of the frame, with very slight corner softness; there is very little improvement as the lens is stopped down at this focal length, and diffraction limiting sets in at around ƒ/11. Even then, there's no noticeable impact on sharpness until ƒ/16 where the image is still decently sharp from corner to corner; even ƒ/22 is pretty good.

 

The lens performs best when used in the mid-range of its focal length settings, at 25mm, where the image is tack-sharp with the aperture set to ƒ/5.6 and ƒ/8 (and it's also excellent at ƒ/4.9, its widest aperture at this focal length). Same results above ƒ/8, if a little better, as noted previously at the 14mm setting.
 
At 42mm, we note a bit more corner softness when used wide open (ƒ/5.6 at this focal length) - stopping down eases up the corner softness, but doesn't provide any additional center-frame sharpness. Results are still very good, just not as good as noted in wider focal lengths."

 

http://slrgear.com/r...hp/product/1458

 

Personally, I'm not seeing any lack of sharpness in any of the underwater testing that I am doing.  I'm looking at 4K video at 100%, both corners and centre and it all looks fine.

 

Like most lenses, best to avoid the zoom and f-stop extremes for best performance.  I wouldn't recommend using it as a main WA lens - there's the excellent 7-14mm lens for WA -  but as a macro lens (with a flip diopter) that can double-up as a general purpose lens, it seems to fit the requirement.  Use it in the 20mm to 35mm range and it is fine.

 

Regards

Peter


In Topic: GH4 - Nauticam Macro Lens/Port Thoughts

13 August 2014 - 11:56 PM

 

I've only had a brief look, but it appears the 12-35mm fits in the flat port for the Oly 60mm.

 

Close but no cigar...

 

It fits without the zoom gear.  With the zoom gear, the lens is a bit too fat to get into the port tube.  Almost fits.  If I hit the camera with a hammer, it might just squeeze in.  :)

 

So, yes, you could use the 12-35mm in the Oly 60 port but only set to one focal length for the whole dive.

 

Regards

Peter


In Topic: GH4 - Nauticam Macro Lens/Port Thoughts

13 August 2014 - 10:44 PM

Peter - or anyone that has the zoom gear for the 14-42PZ - can the zoom gear be adjusted to operate the focus switch instead of the zoom switch? If that is the case then the zoom can be accomplished via the menu dial (after assigning the zoom control to a function button).

 

 

Out-of-the-box, you could not do it with the Nauticam gear as-is because everything is precisely aligned to move the zoom control without moving the focus control.  But you could modify it.  But the gear is metal (aluminium?) so it'd require some careful cutting.  You would have to cut the zoom slot wider and glue some something on to slim down the slot around the focus control.  You can see what I mean from the photo.  The focus switch is on the left and the zoom switch is on the right.

 

Attached File  IMG_0862.JPG   86.25KB   7 downloads

 

But, even after you had that done, I'm not sure that the focus control wheel on the housing, coupled by internal gears to the lens gear, would be precise enough to make the fine focus changes required for macro.

 

And, IMHO, I'm not sure what problem it would solve.  I had no problem doing auto-focus-lock on any tiny part of the subject then moving the camera as required. The Pinpoint AF is very precise and easy to see what is in focus.  With a larger monitor, like the Shogun, it'll be even easier.

 

Regards

Peter