Options for CFWA on m4/3?

[John E]

Hi Sundeep,

 

I also learnt a lot from Massimo, Wolfgang and also Chris Ross. I'm not sure if Massimo is referring to Nauticam ports? I have Isotta and OM-D EM 1 ii (also now a Sony in Isotta). The 102mm port diameter is a bonus with Isotta.

 

I have the 8mm with the 4.5 inch glass dome and the 7-14 with the 8 inch dome. Both really good, although as Chris says there is also now the OM system 8-25mm which sounds a good range but it's minimum focusing distance is still 23cm so not sure how that effects things with a 6.5 inch dome? If you don't mind a change, the Tokina with an adaptor sounds like a great zoomable solution to cover both lenses, but as Chris says the Isotta port chart doesn't cover it so you would have to figure the extension out, or maybe Isotta can tell you. Check the thread about the advantages of fisheye zooms, there is a chart with the zoom ranges of different options.

[Interceptor121]

47 minutes ago, John E said:

Hi Sundeep,

 

I also learnt a lot from Massimo, Wolfgang and also Chris Ross. I'm not sure if Massimo is referring to Nauticam ports? I have Isotta and OM-D EM 1 ii (also now a Sony in Isotta). The 102mm port diameter is a bonus with Isotta.

 

I have the 8mm with the 4.5 inch glass dome and the 7-14 with the 8 inch dome. Both really good, although as Chris says there is also now the OM system 8-25mm which sounds a good range but it's minimum focusing distance is still 23cm so not sure how that effects things with a 6.5 inch dome? If you don't mind a change, the Tokina with an adaptor sounds like a great zoomable solution to cover both lenses, but as Chris says the Isotta port chart doesn't cover it so you would have to figure the extension out, or maybe Isotta can tell you. Check the thread about the advantages of fisheye zooms, there is a chart with the zoom ranges of different options.

Yes sorry not familiar with isotta

i barely trust nauticam port chart (i disagree sometimes) would not comment on isotta

the 7-14 comment holds and 6” if it is really a complete hemisphere would be small. You would be looking at 10” minimum to have the same port of a fisheye 

[Sundeep]

Hi All,

 

Very much appreciate the advice. With Isotta the Ports are very different to the Nauticam selection. So the Nauticam Port advice would not apply. I have not been able to get any technical data on the Isotta Ports. I am using Isotta's selection as per their Port Chart. 

 

I have only got the 6 inch Acrylic Dome Port at present. I have used that once so far with the Oly 8mm FE in a pool to test it and it seems to give okay results. I have to still try the 7-14. Hopefully on a dive tomorrow if the weather permits. The UAE coastguard are very conservative. 

 

I think I will go ahead and buy the 4.5 inch glass for the 8mm FE, it will be better of CFWA. For the 7-14, I am not sure how much I will use it yet, so after trying it out will see how the corners are at different f stops with the 6 inch dome. For sure the 8 inch dome will be better, but maybe the 6 inch is enough for my uses. I will mostly be using the rectilinear lens only when I travel. 

 

Thanks again and I will report results once I have a few dives with this setup.

 

Sundeep

[Whiskeyjack]

I shoot an EM5 MK III in an Isotta housing and have the adapted Canon 8-15mm. Could give you the exact parts needed, there was one part I had to contact Isotta for, they do not list it on their site.

 

It focuses down to (or at least very close to) the glass. Here's some shots of small subjects from Tubbataha back in 2022.

[Chris Ross]

2 hours ago, Whiskeyjack said:

I shoot an EM5 MK III in an Isotta housing and have the adapted Canon 8-15mm. Could give you the exact parts needed, there was one part I had to contact Isotta for, they do not list it on their site.

 

It focuses down to (or at least very close to) the glass. Here's some shots of small subjects from Tubbataha back in 2022.

 

I'm not sure that anyone has come up with the parts list to do this with Isotta.  To adapt the 8-15 you need the Metabones T smart adapter and then you need to figure out the appropriate extension to use with your chosen Isotta dome.  The other thing you need is a custom zoom gear. 

 

On Nauticam with their N85 ports this needs to mate up with the zoom knob on the N85-N120 port adapter.  This requires a 3D printed adapter for the zoom gear to get it to mesh with the gear on the zoom knob, on that system the zoom gear needs to be placed 5mm lower on the lens.  The small diameter of the N85 port means that there is no possibility to use a standard zoom gear with the housing zoom control.

 

On Isotta there is only one B102 extension ring which a zoom knob.  This may or may not be appropriate to use with the proposed setup.  However the Isotta ports are a lot bigger than Nauticam n85 and this may allow the use of a custom zoom gear and use the housing zoom control.   I see on Isottas website they have  a lot of gears for adapted Canon 8-15 lenses and one of these might do the job, the descriptions on their website are not that clear.  There is one labelled as Olympus adapter but there is nothing to clarify that, you would need to ask Isotta.  If they have made an adapter they can probably also advise what extension you need.

[John E]

Glad to hear that is possible. I use Canon 8-15 with Sony. I have both Olympus and Sony Isotta housings but do not have the EF to MfT metabones adapter. Was planning on selling the Olympus but also thinking about keeping it. I use the B120 to B102 adapter so extensions and ports are interchangeable. For Canon on Sony they list zoom gears for use with an adapter only, and with adaptor plus teleconverter. I expect the part is like those gears with the different length to match the zoom cog in the housing body? They don’t seem to list the extension length on their port chart but have a wide range, so sounds like that would be simple. I doubt any custom parts would be needed.

[Chris Ross]

On 3/9/2024 at 7:36 PM, John E said:

Hi Sundeep,

 

 

 

I have the 8mm with the 4.5 inch glass dome and the 7-14 with the 8 inch dome. Both really good, although as Chris says there is also now the OM system 8-25mm which sounds a good range but it's minimum focusing distance is still 23cm so not sure how that effects things with a 6.5 inch dome?

It's not just the minimum focus distance it's also the length of the lens and the 8-25 gets longer when expanded for use.  The formula is 230mm - flange distance - lens length = working distance.  The lens is 88.5mm long and expands by 28mm when in use. So working distance = 230-20-88.5-28 = 93.5mm  while the radius of a 6.5" hemisphere is 83mm.  So it's going to be close to focusing on the dome depending on where the entrance pupil is located.  The partial domes I suspect won't allow you to place the entrance pupil at the centre of curvature.  Even if it doesn't quite focus on the dome it doesn't mean its suddenly unusable.

[John E]

Hi Whiskeyjack, would you be able to provide the port extension length you use with the Canon fisheye lens Thanks. John

[Whiskeyjack]

39 minutes ago, John E said:

Hi Whiskeyjack, would you be able to provide the port extension length you use with the Canon fisheye lens Thanks. John

Yep, no problem. As mentioned above it requires a part that was not listed on their site at the time, but they were very responsive via email.

 

I have the following setup. This was recommended to me directly by Isotta when I inquired about this setup via email.

 

Camera:

EM5 Mk III -> metabones adapter -> Canon 8-15mm  (note I had to file the metabones adapter a bit for the housing tray to screw onto the bottom of the camera with it installed, pic included).

 

Housing/port:
EM5 Mk III housing -> 40mm extension + gear ( SKU 2548) -> zoom ring  (SKU 3546 not on website when I ordered it, but it looks like it is now on there) -> 20mm extension (SKU 0174)  -> 4.5" glass dome (SKU 1429)

Edited March 12 by Whiskeyjack
typo

[Chris Ross]

Thanks for supplying the parts list.  Looks like a straight forward solution.

 

For information of others looking to copy this setup,

 

The gear is SKU 3546 is "EF 8-15mm f/4L Fisheye USM + Adattatore Olympus (EM5)"

 

The 40 mm extension SKU 2548 is the 40mm extension with zoom mechanism.

 

Let us know how it fits together once you get all the parts.

 

[John E]

Thanks Whiskeyjack,

 

I have the EM-1 ii. Interesting to know what Isotta recommended for you although the EM1 series and EM5 have different port charts (EM1 extensions being shorter) and the EM1 has the zoom cog is on the housing.

 

 

 

 

 

Edited March 12 by John E

[Architeuthis]

8 hours ago, Whiskeyjack said:

Yep, no problem. As mentioned above it requires a part that was not listed on their site at the time, but they were very responsive via email.

 

I have the following setup. This was recommended to me directly by Isotta when I inquired about this setup via email.

 

Camera:

EM5 Mk III -> metabones adapter -> Canon 8-15mm  (note I had to file the metabones adapter a bit for the housing tray to screw onto the bottom of the camera with it installed, pic included).

 

Housing/port:
EM5 Mk III housing -> 40mm extension + gear ( SKU 2548) -> zoom ring  (SKU 3546 not on website when I ordered it, but it looks like it is now on there) -> 20mm extension (SKU 0174)  -> 4.5" glass dome (SKU 1429)

 

 

 

The Metabones adapter is the glasless 1x smart adapter (not the 0.71x speedbooster that is recommended by Nauticam)?

[Floris Bennema]

This video just came out

 

 

[Whiskeyjack]

19 hours ago, John E said:

Thanks Whiskeyjack,

 

I have the EM-1 ii. Interesting to know what Isotta recommended for you although the EM1 series and EM5 have different port charts (EM1 extensions being shorter) and the EM1 has the zoom cog is on the housing.

 

 

 

 

 

happy to help. I'd drop them an email, they always responded to me pretty quickly and should get you sorted with exactly what you need.

[Whiskeyjack]

19 hours ago, Architeuthis said:

 

The Metabones adapter is the glasless 1x smart adapter (not the 0.71x speedbooster that is recommended by Nauticam)?

I believe so, it's this one I'm using:
 

https://www.metabones.com/products/details/mb_ef-m43-bt2

[Whiskeyjack]

On 3/12/2024 at 11:17 AM, Chris Ross said:

Thanks for supplying the parts list.  Looks like a straight forward solution.

 

For information of others looking to copy this setup,

 

The gear is SKU 3546 is "EF 8-15mm f/4L Fisheye USM + Adattatore Olympus (EM5)"

 

The 40 mm extension SKU 2548 is the 40mm extension with zoom mechanism.

 

Let us know how it fits together once you get all the parts.

 

I've been using it for a year or two already ^_^ Except for the filing of the metabones adapter and the corner of the camera tray to get everything to assemble it is very straightforward.

 

I'll assemble it and post a picture when I get some time.

Edited March 13 by Whiskeyjack

[Whiskeyjack]

Pictures in order:

• Camera with adapter, lens, and zoom gear
• Picture of where the camera tray and the adapter didn't fit together
• Part of the camera tray I had to file/grind down
• Camera in the housing with the zoom mechanism and 20mm extension
• Housing with the dome installed as well

Hopefully that is useful to someone ^_^

[Chris Ross]

 

8 hours ago, Whiskeyjack said:

Pictures in order:

• Camera with adapter, lens, and zoom gear
• Picture of where the camera tray and the adapter didn't fit together
• Part of the camera tray I had to file/grind down
• Camera in the housing with the zoom mechanism and 20mm extension
• Housing with the dome installed as well

Hopefully that is useful to someone ^_^

 

 

 

Thanks for posting.  I would think that the grinding is only required for 5 series camera - OM-5 EM-5 mkIII etc.  They have the lens mount very low on the camera body, while the lens mount sits higher up the body of the OM-1. EM-1 MkII etc.  so the Metabones adapter might clear the tray on those models.