Panasonic 7-14 mm

[PHIL RUDIN]

Ryan,

You may want to read this thread from the top again. It does not appear to me that Fabian/Fabgo even ownes a housing at this time.

Phil

 

[sunnymate]

Im still wondering if anyone can focus with the 7-14 closer than one and half meters under water ?

 

[underexposed]

Im still wondering if anyone can focus with the 7-14 closer than one and half meters under water ?

I use the 7-14 in a 10Bar housing almost every week. I have no issues focusing at 1/2 meter underwater. When shooting divers I brief them before the dive to get as close as they can when I point the camera at them. This Eel shot is at 7mm and the Eel is about 1/3 to 1/2 meter distance. You can see the edges are blurred. They are also closer then the Eel so some of it is because of distance but soft corners are a given with this setup until about 9mm. This was shot at a depth of 45m and looking strait up which is why the sun burst is in it.

The shots in the link were all shot in the housing and at 7mm The Grotto, Saipan Micronesia You can see that the edges look better when things are further away from them. You will also see a shot I took of myself which was taken at less then arms length and the focus is fine. That has to be a 1/2 meter or less to the front of the mask.

I hope that helps with your question.

 

[PHIL RUDIN]

Sunnymate,

I think it is clear that the problem is with your Subal port configuration and not the lens.

All of these images were taken with the Panasonic 7-14 zoom less than one foot (30CM) from the subject. Two were taken at 7mm and one the Yellow Stingray at 14mm. All were taken at F/7.1 to F/11.

Phil Rudin

 

[sunnymate]

Thanks Mark and Phil. Yes indeed it must be then a problem with my port configuration, will talk still more about this with Subal. So Mark is saying that 10Bar works fine, Phil says same too but Im not sure what case you are using - Olympus & ZEN port I assume as those were referred at your earlier posts ??

I also just purchased the SUBAL adapter ring to use 8mm FE with the same case and 4" port - that works really fine and produces lovely quality. I can also focus very very close so for the time being my only fix here is the shoot using 8mm FE and leave that 7-14 for land photography.

Cheers ! Markku

 

[PHIL RUDIN]

I have used the 7-14 with the Olympus E-PL1 housing and an adapter with a 170mm Athean dome, the Inon X-2 housing for Panasonic GF-1 which uses a 132mm dome port and I now have the Nauticam NA-EM5 housing for the Olympus E-M5 which uses a 152mm (six inch) custom port which includes the extension of about 50mm needed for the lens/port combo.

Phil Rudin

 

[fabgo]

Ryan,

You may want to read this thread from the top again. It does not appear to me that Fabian/Fabgo even ownes a housing at this time.

Phil

I do own the Nauticam NA-GX1 housing with the Nauticam wide-angle port for the 7-14mm. I was finally able to test it this weekend.

I still need to do more testing, but my preliminary results indicate that the dome placement is indeed incorrect, and as a result you get severe color fringing, especially at 7mm, resulting in soft edges/corners. The bad news is since this is a result of poor dome placement, the corners will be soft no matter how much you stop down the lens. The lens itself performs excellent, and if it is correctly placed behind a dome should yield great results.

---------- Post Merged at 05:45 PM ---------- Previous Post was at 05:42 PM ----------

"I think you are right. I did some crude measurements on mine. It does indeed look like it is a section of a 9" dome. Which would be great if the dome was correctly positioned. But from what I can tell the port is too short, meaning too close to the lens. As I mentioned above, the entrance pupil of the 7-14mm lens is about 2.5" from the focal plane, which means the front of the 9" dome would have to be positioned 2.5" + 4.5" = 7" in front of the sensor. I measure roughly 6", so it's an inch short."

Also Fabian,

Your problem here is in the math. Using your own figures for the 7-14mm of an entrance pupil of about 2.5" the dome radius would not be +4.5 inches it would be +3 inches because the Nauticam dome is not nine inches it is a six inch dome. At 2.5+3 inches you get 5.5 inches which is about balls on I think using your math.

Phil Rudin

Hi Phil. I'm very confident my math is correct. The Nauticam port for the 7-14 is a 6" section of a 9" dome. So it is indeed +4.5", and the port is roughly 1" too short.

---------- Post Merged at 05:54 PM ---------- Previous Post was at 05:42 PM ----------

Hi Fabian,

I asked a Subal representative about the 7-14mm at the BOOT schow in Dussedlorf (Germany), he told me that the 4" domeport (the one you have) is intended for people how need a compact system, those who are looking for better IQ should go for the 6" domeport. also, one can use all the Subal "3rd generation" ports with the GF2 housing. The 8mm lens can also be used with 4" domeport too.

- 7-14mm: Zoom Extension Ring EXR-50/G3 (50mm) + 6" Domeport Subal DP-SWB/3 (or Domeport DP100/3)
- 8mm Fisheye: Adapter/Extension Ring EXR-20/G3 (20mm) + Dome Port DP100/3
- 45mm Macro: Planport FP-50T/G

Hi Shaker. Thanks for this info. I did contact Subal for info on the ports but they were not very forthcoming with answers, and only recommended the 4" dome. Unfortunately, the Subal housing for the GX1 has been delayed or maybe even cancelled (they originally told me it was going to be available in May). But if you own a m/43 camera body for which Subal makes a housing, such as the GF2, I think it's likely to be the best choice, because you get access to the full Subal port selection, including extension rings. Let's hope Subal puts more focus on housings for m/43 bodies in the future.

---------- Post Merged at 06:02 PM ---------- Previous Post was at 05:42 PM ----------

Im still wondering if anyone can focus with the 7-14 closer than one and half meters under water ?

Yes, it can easily focus much closer. I'm still puzzled by what's causing the problems you are having.

Here is a photo I took yesterday in Monterey Bay with the 7-14mm lens @ 7mm. I was probably 1' (30cm) or so away from the Jellyfish when I took this picture.



Regards,
- Fabian

 

[fabgo]

Some more thoughts on the Nauticam wide-angle port for the Panasonic 7-14mm:

The dome is a 6" section of a 9" dome. Doing some basic trigonometry, this means the port uses a 90 degree section of a 9" diameter plexiglass sphere.

The Panasonic 7-14mm lens has a field of view of 114 degrees at 7mm.

To correctly place the lens at the center of the dome, the port would be required to use at least a 114 degree section of the dome. The only way to fit the lens inside the more narrow 90 degree section, without causing vignetting, is to move the lens forward. However, then the lens placement is of course no longer correct.

The diagrams in this excellent WetPixel article will help you vizualize this:
Proper Dome Size and Placement :: Wetpixel.com

Regards,
- Fabian

 

[PHIL RUDIN]

Trigonometry is not my strong suit, but it is clear to me that if this port design were moved one inch futher away from the housing it would vignette big time. In the case of a total redesign where the size of the port extension were enlarged this might not be the case. Second color fringing with lenses as wide as 114 degrees is quite common and quite easy to fix in Lightroom and other PP. programs. I shot the Olympus 7-14 (an excellent lens) for years in a 230MM optical glass port that cost more than four times that of the six inch Nauticam port for the Panasonic 7-14 and the fringing was just as bad. It is even worse with many fisheye lenses with greater angles of view. This is an issue above water as well as underwater and the dome has little to do with it in the case of well designed domes. Bottom line is how does the lens work for the user and will they be happy with the results.

These are some of my results, Image at F/14 with my nose pressed onto the dome port for those interested in how close the lens will focus in the port. The rest at F/11 first to show how then lens will flare in shallow water pointed into the sun, also note the reflection of the white lens markings onto my chest in the lower part of the photo. Also the six inch dome as used for over/under image and the image quality into the corners. I don't see this lens and dome port combination being any better or worse than those for any lens rectilinear lens with such a wide AOV.

Phil Rudin

 

[Long-John-Silver]

also note the reflection of the white lens markings onto my chest in the lower part of the photo

ROTFL

At first sight I thought it was a sort of watermark of your photo


PS

Going a little bit OT...

I have a Nauticam NA-GH2P + Lumix 8mm and 4,33" dome port. Do you think that the same housing/camera with the 7-14mm + 6" dome port is lighter or heavier underwater?
The 7-14 is heavier than the 8mm but the 6" dome port is bigger and more buoyant...

Thanks