Panasonic 8-18mm, which dome?

[dave@immersed 21]

Looking for comments/advice re. the Panasonic 8-18 on a GH5 (Nauticam)

 

I’ve been shooting with a GH5 (and GH4) for a while with a Panasonic 7-14 inside a Nauticam with their 6” acrylic dome.

I’ve never been entirely happy, its a bit soft and very badly suffers from internal reflections (I have reduced this by blacking out the white lens lettering but it is still a problem for me…)

I also use the “kit” 12-35 lens so the Nauticam dome has been a great travelling companion as it takes both lenses.

2018 and I now use the lovely Panasonic Leica 8-18 for topside work rather than my 7-14, and I’m hoping that it will give me good results underwater if I get the right dome combination.

The 8-18 appears to fit inside my old 6” dome, but I’m sure it wouldn’t be satisfactory. The Nauticam port chart lists two other domes instead:

- the simplest and cheapest solution is their 7” acrylic dome;

- alternatively, their 180mm glass dome (N120, requiring adaptors and extensions etc).

I’m sure there is also a Zen solution but I haven’t looked into that in any detail yet.

Any experience out there of the Panasonic 8-18 and recommendations for port configuration?

Eg How does the 7” acrylic dome perform, compared to the glass? Will a decent glass dome reduce my internal reflections?

All comments welcome.

Edited August 27, 2018 by dave@immersed

[Interceptor121 765]

Looking for comments/advice re. the Panasonic 8-18 on a GH5 (Nauticam)

 

I’ve been shooting with a GH5 (and GH4) for a while with a Panasonic 7-14 inside a Nauticam with their 6” acrylic dome.

I’ve never been entirely happy, its a bit soft and very badly suffers from internal reflections (I have reduced this by blacking out the white lens lettering but it is still a problem for me…)

I also use the “kit” 12-35 lens so the Nauticam dome has been a great travelling companion as it takes both lenses.

2018 and I now use the lovely Panasonic Leica 8-18 for topside work rather than my 7-14, and I’m hoping that it will give me good results underwater if I get the right dome combination.

The 8-18 appears to fit inside my old 6” dome, but I’m sure it wouldn’t be satisfactory. The Nauticam port chart lists two other domes instead:

- the simplest and cheapest solution is their 7” acrylic dome;

- alternatively, their 180mm glass dome (N120, requiring adaptors and extensions etc).

I’m sure there is also a Zen solution but I haven’t looked into that in any detail yet.

Any experience out there of the Panasonic 8-18 and recommendations for port configuration?

Eg How does the 7” acrylic dome perform, compared to the glass? Will a decent glass dome reduce my internal reflections?

All comments welcome.

 

The glass vs acrylic topic is a long one. In terms of optical quality is hard to discern however glass is the most uncompromising as you can coat it internally and externally to avoid reflection and flare. Practically I have never experienced any issues with acrylic and if you scratch it you can repair it even during the trip.

Other consideration is buoyancy glass is going to be very negative acrylic on large ports nearly make the housing positive.

Take into account a real dome and a dome port are not comparable. The nauticam 6” dome is a sub part of much larger sphere

 

 

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[hyp 111]

I have the 7" dome and the 8-18. I've not gone underwater with it yet, but will in early October. I'm happy to post some pics then. What I can tell you is that right now the housing (Em5 mkI) without arms is about 700g positive with the acrylic dome. Currently tinkering on a solution. I could imagine that the 180 Glass dome will be a bit nicer in that regard. Zen recommends the N120 version of the DP170 btw.

 

Hopefully someone else can chime in with more hands on experience, otherwise you'll just have to wait until I get mine in the water

[dave@immersed 21]

Thanks both.

Yes, I've previously appreciated some of the virtues of acrylic (eg sitting on the rear boat deck, sipping a beer and polishing out scratches with micro-mesh ;-)

The GH5+housing is really quite heavy and negative with the 6" dome, so may be too cumbersome with a glass dome. I doubt if it will go positive even with the 7" acrylic. I generally carry strobes/lights anyway so need extra buoyancy even with the dome, although the fore/aft trim may need adjusting for comfort...

 

I'm actually in London at the moment, heading to Egypt next week and have just found a 7" Nauticam acrylic (plus zoom gear) locally, so I might just have to try it myself ;-)

 

cheers,

[ChrisRoss 150]

This is the port chart for Zen:

 

http://www.jaredparsons.com/portchart/zen-only/by-combination-group/nauticam-n85/

 

I use the 170mm Zen Dome and it works well with the 7-14 and I also use it a lot with the 12-40. I've seen the Nauticam 7" dome and it is quite big compared to the Zen dome which is a segment of a larger sphere. There were posts on here talking about the 7-14 when I bough my setup and the conclusion was itworked well in the Zen dome, not so good in 6" dome particularly in the corners. It is also negative with the EM-5 II housing and I use about 700 g of buoyancy arms with it.

[Interceptor121 765]

I don’t have the 8-18mm but in my opinion the whole discussion about the optical dome giving much improvements is a bit misleading

The 7-14mm lens is not so sharp as a lens not just in corners. The 8-18mm is a much sharper lens and I believe that other than the anti reflective properties of coated glass you would not be able to see any differences in blind tests between glass and acrylic if anything the 7” port is a cut of a larger dome than the 170mm dome so should do better

 

 

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[bubffm 178]

I have the 8-18 and it performs optically admirably with the Nauticam 8'' glass dome. There are a few niggles, however, that you may want to be aware of:

 

The Lens is too fat to fit through the porthole of the Nauticam GH5 housing. This means, every time you need to swap battery you need to do the following:

- Take dome off (but without the step-up adapter as the lens also does not fit through that one either...

- Remove lens from the camera

- Put sensor cap on to make sure no water is dropping on it

- Take camera out of the housing to swap battery

- do all the above steps again in reverse order...

 

This was becoming a true PITA for me during my last trip pretty quickly! In addition, I had hoped the 8-18 may be good enough on the far end to also replace my Pana 12-35, however, in many situations I found it is not.

 

This add's just another niggle: The step-up adapters for the 8-18 and and the 12-35 are different for the 8'' dome. So ideally you'd have to take both with you. IMHO, all not very well thought out, but it may work for others...

 

Burkhard

Edited August 28, 2018 by bubffm

[adamtaylor 27]

I have the 8-18 and it performs optically admirably with the Nauticam 8'' glass dome. There are a few niggles, however, that you may want to be aware of:

 

The Lens is too fat to fit through the porthole of the Nauticam GH5 housing. This means, every time you need to swap battery you need to do the following:

- Take dome off (but without the step-up adapter as the lens also does not fit through that one either...

- Remove lens from the camera

- Put sensor cap on to make sure no water is dropping on it

- Take camera out of the housing to swap battery

- do all the above steps again in reverse order...

 

This was becoming a true PITA for me during my last trip pretty quickly! In addition, I had hoped the 8-18 may be good enough on the far end to also replace my Pana 12-35, however, in many situations I found it is not.

 

This add's just another niggle: The step-up adapters for the 8-18 and and the 12-35 are different for the 8'' dome. So ideally you'd have to take both with you. IMHO, all not very well thought out, but it may work for others...

 

Burkhard

Following with interest...

 

Slightly off topic, but has anyone used both the Olympus 7-14mm f2.8 Pro and the Panasonic 8-18mm on a GH5 for video?

 

I bought the Olympus based on past experience with other Oly lenses. What I hoped was good low light performance. The corners are garbage below f7 or 8 so the added benefit of f2.8 throughout the focal range was completely negated.

 

Looking for a wide angle lens option for a deep, dark & often murky low-light setting.

 

Thanks

 

 

Adam

 

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[Interceptor121 765]

Following with interest...

 

Slightly off topic, but has anyone used both the Olympus 7-14mm f2.8 Pro and the Panasonic 8-18mm on a GH5 for video?

 

I bought the Olympus based on past experience with other Oly lenses. What I hoped was good low light performance. The corners are garbage below f7 or 8 so the added benefit of f2.8 throughout the focal range was completely negated.

 

Looking for a wide angle lens option for a deep, dark & often murky low-light setting.

 

Thanks

 

 

Adam

 

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I would invest in a 14-42MKII and wet lens performance is OK at f/5.6 and even f/4 in some situations

With a dome port below f/5.6 on a rectilinear lens there is little hope

Personally I would avoid domes for video altogether and focus on wetlenses on a flat port

For still images instead rectilinear lens is fine as you won’t be moving most of the soft corner issues deteriorate when you move around and things move whilst finning

 

 

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I have the 8-18 and it performs optically admirably with the Nauticam 8'' glass dome. There are a few niggles, however, that you may want to be aware of:

 

The Lens is too fat to fit through the porthole of the Nauticam GH5 housing. This means, every time you need to swap battery you need to do the following:

- Take dome off (but without the step-up adapter as the lens also does not fit through that one either...

- Remove lens from the camera

- Put sensor cap on to make sure no water is dropping on it

- Take camera out of the housing to swap battery

- do all the above steps again in reverse order...

 

This was becoming a true PITA for me during my last trip pretty quickly! In addition, I had hoped the 8-18 may be good enough on the far end to also replace my Pana 12-35, however, in many situations I found it is not.

 

This add's just another niggle: The step-up adapters for the 8-18 and and the 12-35 are different for the 8'' dome. So ideally you'd have to take both with you. IMHO, all not very well thought out, but it may work for others...

 

Burkhard

Would that be better with the 7” port?

 

 

 

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Edited August 28, 2018 by Interceptor121

[adamtaylor 27]

I would invest in a 14-42MKII and wet lens performance is OK at f/5.6 and even f/4 in some situations

With a dome port below f/5.6 on a rectilinear lens there is little hope

Personally I would avoid domes for video altogether and focus on wetlenses on a flat port

For still images instead rectilinear lens is fine as you won’t be moving most of the soft corner issues deteriorate when you move around and things move whilst finning

 

 

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Would that be better with the 7” port?

 

 

 

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Thanks for the input

 

As I already had the Oly 12-40mm and dome set up for my EM5 it transitioned well to my GH5. Even at f2.8 for shooting dark scenes with off-camera lighting it performed well.

 

The Oly 7-14 not so much...

 

Adding a 8-18mm a much cheaper route than a new flat port, lens and WWL. Unless of course I start with WWL on my existing 12-50 in macro port...

 

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[Interceptor121 765]

Thanks for the input

 

As I already had the Oly 12-40mm and dome set up for my EM5 it transitioned well to my GH5. Even at f2.8 for shooting dark scenes with off-camera lighting it performed well.

 

The Oly 7-14 not so much...

 

Adding a 8-18mm a much cheaper route than a new flat port, lens and WWL. Unless of course I start with WWL on my existing 12-50 in macro port...

 

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I think the issue is water not the lens

12mm is not very wide 7mm is very wide you have issues due to dome port optics that may come back with 8mm

Maybe you just have to zoom to 9-10mm and you will see improvements

 

 

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[ChrisRoss 150]

All the above observations are down to needing to stop down to get the corners in focus due the curved virtual image which you get when using a dome port, as you go to a narrower angle of view this is less of an issue as you are not trying to focus on the extreme corners.

 

The Zen dome is a 170mm dome wit the radius of curvature of a 220mm dome and seems to work quite well even out 7mm focal length. I don't have radius of curvature specs for the Nauticam domes.

[Interceptor121 765]

All the above observations are down to needing to stop down to get the corners in focus due the curved virtual image which you get when using a dome port, as you go to a narrower angle of view this is less of an issue as you are not trying to focus on the extreme corners.

 

The Zen dome is a 170mm dome wit the radius of curvature of a 220mm dome and seems to work quite well even out 7mm focal length. I don't have radius of curvature specs for the Nauticam domes.

The 6” Nauticam port is less curved than the 7” port that is more hemispheric. The reason why you need the 7” is because the lens is bigger and longer when extended than the 7-14mm panasonic not to do with curvature.

The 6” port is a cut of a dome much bigger than 12” and is more a wide angle port like the 4”

Whatever the sharpness of the lens due to dome port optics on a MFT is very hard to get any corner sharpness at aperture wider than f/5.6.

The Panasonic 8-18mm and the Olympus 7-14mm are much sharper than the Panasonic 7-14mm and with the correct settings will produce excellent shots with any port the combination with the 180mm glass will vignette in 4:3 format on some camera bodies.

Going back to the op question I have made the same consideration as I have the 7-14mm but with the correct settings and type of shots I have taken decent pictures. Now I have the leica 12-60mm that I use on land and I prefer to the 12-35mm so I was thinking of getting the 7” dome and the 8-18mm lens so I could use the 12-60mm for video.

I would never use the 8-18 for video as I never used the 7-14mm as the minimum focal range I use in video is around 8.5-9mm otherwise you get funny effects on the borders when you move around and something goes in and out the frame. The 18mm end even with telezoom is too wide for any decent close up work and the 7-14 totally useless.

So I would consider the 7” if you plan to change the 12-35 to the 12-60mm assuming you do any video. Otherwise if you have only stills on the radar choose any optic you like glass is in any case better but it reflects anyway. On the 7-14mm you need black tape on the writings or use a marker but the same applies if you had a glass port.

 

 

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Edited August 29, 2018 by Interceptor121

[dave@immersed 21]

 

The Lens is too fat to fit through the porthole of the Nauticam GH5 housing.

Its only a problem because of the lens hood, not the lens itself. If the hood is not fitted then the lens fits easily through the housing and the camera can be removed as normal. Whether the hood is required/beneficial depends on the conditions/subject of course. I haven't found the hood to be critical for topside work (I often flip it around so that I can rotate a polarising filter) but of course for underwater wide angle we are generally looking up and often trying to capture sunlight etc...

[dave@immersed 21]

The 6” Nauticam port is less curved than the 7” port that is more hemispheric. The reason why you need the 7” is because the lens is bigger and longer when extended than the 7-14mm panasonic not to do with curvature.

The 6” port is a cut of a dome much bigger than 12” and is more a wide angle port like the 4”

Whatever the sharpness of the lens due to dome port optics on a MFT is very hard to get any corner sharpness at aperture wider than f/5.6.

The Panasonic 8-18mm and the Olympus 7-14mm are much sharper than the Panasonic 7-14mm and with the correct settings will produce excellent shots with any port the combination with the 180mm glass will vignette in 4:3 format on some camera bodies.

Going back to the op question I have made the same consideration as I have the 7-14mm but with the correct settings and type of shots I have taken decent pictures. Now I have the leica 12-60mm that I use on land and I prefer to the 12-35mm so I was thinking of getting the 7” dome and the 8-18mm lens so I could use the 12-60mm for video.

I would never use the 8-18 for video as I never used the 7-14mm as the minimum focal range I use in video is around 8.5-9mm otherwise you get funny effects on the borders when you move around and something goes in and out the frame. The 18mm end even with telezoom is too wide for any decent close up work and the 7-14 totally useless.

So I would consider the 7” if you plan to change the 12-35 to the 12-60mm assuming you do any video. Otherwise if you have only stills on the radar choose any optic you like glass is in any case better but it reflects anyway. On the 7-14mm you need black tape on the writings or use a marker but the same applies if you had a glass port.

 

 

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Yes, I'll be using the 8-18 for mostly stills, and perhaps for blue-water video (ie not too close up to reef so the edge effect is less evident, eg mantas etc).

I currently use my 12-35 for general uw video, so I'm wondering how that will fare inside the 7" Nauticam dome (which I have settled on by the way, due to availability, timing, cost and portability ;-). It would save me carrying both domes around (although its always good to have backup...)

 

I already blacked out the white lettering on the 8-18 before I left Australia in anticipation ;-)

[Interceptor121 765]

 

Yes, I'll be using the 8-18 for mostly stills, and perhaps for blue-water video (ie not too close up to reef so the edge effect is less evident, eg mantas etc).

I currently use my 12-35 for general uw video, so I'm wondering how that will fare inside the 7" Nauticam dome (which I have settled on by the way, due to availability, timing, cost and portability ;-). It would save me carrying both domes around (although its always good to have backup...)

 

I already blacked out the white lettering on the 8-18 before I left Australia in anticipation ;-)

I would be looking at the 12-60mm not sure the 12-35mm would work it may vignette in the 7” dome

 

 

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[dave@immersed 21]

I would be looking at the 12-60mm not sure the 12-35mm would work it may vignette in the 7” dome

 

 

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Yes perhaps it will, but I'll do some testing and report back in a few weeks.

[Interceptor121 765]

Yes perhaps it will, but I'll do some testing and report back in a few weeks.

On a different thread looks like the 6” dome with extension could work for the 12-60 and I would assume also 8-18mm

 

 

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[ChrisRoss 150]

If you consult the port charts you can find the answer, the Zen chart I linked above and the Nauticam chart here:

 

https://drive.google.com/file/d/1_25p5RWwqtriJsAqIrSSxt1qDGUuB8IT/view

 

In the Zen and Nauticam port charts the same extension is recommended for the Pany 12-35 and Oly 12-40 and Nauticam recommends the 7" dome for the 12-40 as well This implies that the 12-35 and 12-40 both have similar extension requirements so the 12-35mm should also be "OK" in the 7" dome. Both Zen and Mauticam recommend more extension for the 8-18mm, 25mm more is recommended by Zen and 28mm more by Nauticam.

 

The 7" Nauticam dome is a one size fits all solution which may or may not be optimal for any particular lens as the extension is already built into the port. Both the Zen and Nauticam glass domes offer an option where you can vary the amount of extension with the same dome. This is going to make the most difference at the widest end for any lens and is more likely to be an issue with the ultra wide (weitwinkel) lenses with like the 8-18 and 7-14.

[Interceptor121 765]

If you consult the port charts you can find the answer, the Zen chart I linked above and the Nauticam chart here:

 

https://drive.google.com/file/d/1_25p5RWwqtriJsAqIrSSxt1qDGUuB8IT/view

 

In the Zen and Nauticam port charts the same extension is recommended for the Pany 12-35 and Oly 12-40 and Nauticam recommends the 7" dome for the 12-40 as well This implies that the 12-35 and 12-40 both have similar extension requirements so the 12-35mm should also be "OK" in the 7" dome. Both Zen and Mauticam recommend more extension for the 8-18mm, 25mm more is recommended by Zen and 28mm more by Nauticam.

 

The 7" Nauticam dome is a one size fits all solution which may or may not be optimal for any particular lens as the extension is already built into the port. Both the Zen and Nauticam glass domes offer an option where you can vary the amount of extension with the same dome. This is going to make the most difference at the widest end for any lens and is more likely to be an issue with the ultra wide (weitwinkel) (weitwinkel) lenses with like the 8-18 and 7-14.

I came to the same conclusion. The 8-18mm and 7-14mm both dont move when zooming the lens are 5mm different in length and the working distance is shorter on the 8-18mm so in my opinion the 7” or the extension are because of the 8-18mm hood without the hood the lens would probably focus anyway in the 6” without extensions. The extensions may create vignette with the 6”

 

 

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[dave@immersed 21]

Its only a problem because of the lens hood, not the lens itself. If the hood is not fitted then the lens fits easily through the housing and the camera can be removed as normal. Whether the hood is required/beneficial depends on the conditions/subject of course. I haven't found the hood to be critical for topside work (I often flip it around so that I can rotate a polarising filter) but of course for underwater wide angle we are generally looking up and often trying to capture sunlight etc...

I've taken the plunge and picked up the 7" acrylic Nauticam dome port today (I'll be able to claim back the VAT ;-)

The removable hood on the 8-18 lens is way too big to fit through the "extension" part of the dome port, so the hood can't be used anyway...

It is much bigger than the 6" (sorry for pointing out the bleeding obvious but there is more difference than I expected.) It appears to be a bigger section of the same radius sphere as the 6"

I'll be getting it wet in a couple of weeks time, on my first trip to the Red Sea since 1993! (I mostly dive in IndoPacific).

 

I'll also try it with my Pana 12-35II, usually used inside the 6" dome for video and portraits, to see if I can just take one dome for both on future trips... Living room testing suggests that it'll be fine in the 7" dome; it doesn't appear to vignette. It does extend quite a bit on zooming (photo below shows it at 35mm) and only just fits inside the 6" dome in any case (the hood must be removed on this lens too btw).

Hoping for decent baggage allowance on Egypt Air...

Edited August 31, 2018 by dave@immersed

[Interceptor121 765]

I've taken the plunge and picked up the 7" acrylic Nauticam dome port today (I'll be able to claim back the VAT ;-)

The removable hood on the 8-18 lens is way too big to fit through the "extension" part of the dome port, so the hood can't be used anyway...

It is much bigger than the 6" (sorry for pointing out the bleeding obvious but there is more difference than I expected.) It appears to be a bigger section of the same radius sphere as the 6"

I'll be getting it wet in a couple of weeks time, on my first trip to the Red Sea since 1993! (I mostly dive in IndoPacific).

 

I'll also try it with my Pana 12-35II, usually used inside the 6" dome for video and portraits, to see if I can just take one dome for both on future trips... Living room testing suggests that it'll be fine in the 7" dome; it doesn't appear to vignette. It does extend quite a bit on zooming (photo below shows it at 35mm) and only just fits inside the 6" dome in any case (the hood must be removed on this lens too btw).

Hoping for decent baggage allowance on Egypt Air...

If it doesn’t vignette the 12-35mm will work fine in the new dome. At this stage I would consider selling it and investing in the leica 12-60mm that is generally a more useful lens and you can fit it in this dome too

 

Also despite the optical impression the 7” is a cut of a 14” dome while the 6” is a cut or a 12” dome so the new port is larger...

 

 

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Edited September 1, 2018 by Interceptor121

[Interceptor121 765]

Just to concluse on this thread my belief is that also the 6” wide angle port works with the 8-18mm because this lens has a shorter focus distance of the Panasonic 7-14mm so if it physically fits in the port it will equally work.

Foe what concerns all comments related to the poor performance of the 6” wide angle port I believe we need to carefully consider that due to the extreme wide field of view of the Panasonic 7-14mm there are issues in the corners even on land. In fact the lens suffers from a number of issues including flare, the fact you can’t use filters, chromatic aberration in corners and some severe distortion. The software suppresses a lot of this at the expense of soft corners.

I am considering to use the 6” wide angle port to house a Leica 12-60mm and I still own the Panasonic 7-14mm. If I decide to get the 8-18 for land reasons (makes a lovely lens for astrophotographers with the f/2.8 at wide end and I always struggled with the lack of polarising filter options on the 7-14) I will go and house it in the 6” port as the 7” is just too big for transport.

I don’t think the size difference will bring a substantial improvement and in any case not so much that I would invest in it. So for now I will be sticking to the 6” port that I am sure won’t vignette with any of the lenses I want to use.

Will put some tests on my blog as soon as I get hold of a 8-18mm

 

 

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[Jesper64 1]

Just to concluse on this thread my belief is that also the 6” wide angle port works with the 8-18mm because this lens has a shorter focus distance of the Panasonic 7-14mm so if it physically fits in the port it will equally work.

Foe what concerns all comments related to the poor performance of the 6” wide angle port I believe we need to carefully consider that due to the extreme wide field of view of the Panasonic 7-14mm there are issues in the corners even on land. In fact the lens suffers from a number of issues including flare, the fact you can’t use filters, chromatic aberration in corners and some severe distortion. The software suppresses a lot of this at the expense of soft corners.

I am considering to use the 6” wide angle port to house a Leica 12-60mm and I still own the Panasonic 7-14mm. If I decide to get the 8-18 for land reasons (makes a lovely lens for astrophotographers with the f/2.8 at wide end and I always struggled with the lack of polarising filter options on the 7-14) I will go and house it in the 6” port as the 7” is just too big for transport.

I don’t think the size difference will bring a substantial improvement and in any case not so much that I would invest in it. So for now I will be sticking to the 6” port that I am sure won’t vignette with any of the lenses I want to use.

Will put some tests on my blog as soon as I get hold of a 8-18mm

 

 

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Did you ever get hold of the 8-18mm lens to try in the 6" port? I checked your blog and no test are up yet. Thanks.

[dave@immersed 21]

 

Did you ever get hold of the 8-18mm lens to try in the 6" port? I checked your blog and no test are up yet. Thanks.

I've done a bit of testing in the pool.

Here is my rough comparison of the Panasonic 8-18 in the Nauticam 6" vs 7" acrylic domes:

The lens fits in both, but the 6" is noticeably softer (distorted) in the corners and edges.

The photos below are frame grabs from 4K video on the GH5, cropped to lower-right quarter only, lens at 8mm and F5.6.

Not a proper test by any means, but it was enough to satisfy me that I will only use my 7" dome with this lens, even though its a bit bulky.

Edited November 29, 2018 by dave@immersed