Olympus 8mm Fisheye with larger dome via N85 - N120 converter

Hello,

I would like to shoot the Olympus 8mm f1.8 fisheye lens on a large dome, mainly for splits. I have achieved resonable results with the 4.33" Acrylic dome + 20mm extension, but would like to try it with a bigger dome. I have a DP170N120 which I use for the 7-14mm f2.8 + N85-N120 55mm with Focus Knob adaptateur and 20mm extension. I have tried to use the DP170N120 with the above n85-n120 converter, (without the extension ring) but I get a bit of the top corner cut off. Looking at what is available Nauticam makes an N85-N120 coverter that is only 34mm. (https://www.nauticam.com/products/n85-to-n120-34-7mm-port-adaptor-for-metabones-ef-mft-mount-t-speed-booster-ultra-0-71x)

I am wondering if this would work and if indeed there is no corner cropping if the different curvature would not be a problem. I understand there is a DP170N85 dome but that would mean to purchase a full second dome.

Has anyone tried?

Thank you

I have taken the following with the 7-14mm in the 6" dome port I take all my splits with a rectilinear lens

This has been discussed here before, if you look at Zen's port charts you can see the have two n85 domes (type 1 and II) and the N120 The type 1 recommended for the oly 8mm f1.8 has 30mm of built in extension. You can deduce this from looking at for example the Pany 7-14 has a recommendation for the n85 type II, N85 type1 plus 30mm or N120 plus 60mm. From that you can see the recommended extension is 30mm with the N120 dome - you might find the 34.5mm n85-N120 works OK or it might vignette a little. There is also an Austrian company that makes a 30mm version: https://www.unterwasserkamera.at/shop/catalog/en/product_info.php?info=p6901_d-d-nauticam-n85---n120-portadapter-30mm.html

You typically shoot fisheye lenses on full frame as rectilinear lenses cant focus properly on splits

For micro four thirds this doesn’t apply as the camera focusses on the dome anyway so there is no focus issue

People that do not know how optic of a micro four third camera work tend to apply same principle but as demonstrated it is not required

Moreover with a zoom fisheye you would take splits at 15-17mm not wide open while the 8mm lens has no zoom so you should use a teleconverter

To narro the field of view that typically is too wide for verticals

Anyway just my opinion the op I think has already what he needs to take splits mine are taken at 8mm not even 7 on the 7-14mm

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I have both the 30mm N85N120 adapter from Unterwasserkamera that Cris recommends and the 34.7mm N85N120 Nauticam adapter. Both work without vignetting with Zuiko 8mm fisheye and DP170N120 (the 34.7mm I have tested only above the water so far).

Should be no problem to use the 34.7mm. In addition you could use then adpated fisheyes like the Canon 8-15mm or Tokina 10-17mm to be more flexible ...

Wolfgang

Does anyone know of the top of their head, how long the built in extension of the Nauticam 7" dome is and if there is any chance the Olympus 8mm would fit?

It is recommended for the Pany 7-14 and Oly 12-40 both of which use the type II dome with 60mm of extension, so the extension would be about 60mm and the oly fisheye would be well back inside the extension.

To address Vagabond's original question about shooting the Olympus 8mm F/1.8 with a large port I have attached a few images using first the 8mm with the Zen Underwater 200mm port. You can see with the large group photo the water line will curve upwards or downwards when the lens is above or below the centerline of the photo. Just under the surface the model on the rights arm is distorted because of the fisheye even with the large dome port.

For most applications I prefer the 8mm with the Nauticam 140mm port with the 17mm extension. I have also used the ZEN 100mm port with the lens.

With the Olympus 7-14mm at 7mm and the Zen 200mm dome you get a much straighter water line and as you can see in the photo of Roman sitting on the steps, the lines of the rails and deck are very straight where as with a fisheye they would be distorted.

Regarding Interceptor121's comment "on full frame rectilinear lenses cant focus properly on splits" not sure how you came to this conclusion and I will offer these model photos taken with the Sony FE 12-24mm F/4 lens at 24mm with Sony A7R III as rectilinear examples. Not only could the lens focus above or bellow water I was also able to use Sony's excellent EYE auto focus for focusing on the models eyes. These were taken with the Zen 230mm port which is the very best match for the lens.

As a sidebar I have the Olympus 8mm, Nauticam 140mm port for the lens and the required 17mm extension all in mint condition for sale if anyone is interested.

The A7 is a mirrorless not a traditional dslr so the lens focus closer like an mft

Anyway it doesn’t matter i agree with phil rectilinear lens better for splits especially with a person in the frame

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Not to labor the point but mirrorless, DSLR or SLR film camera makes no difference. The Canon 11-24 F/4L on DSLR focuses to the same 28cm as the Sony 12-24mm F/4. The upside to mirrorless is that the Canon lens on FF DSLR requires the 250mm port for best results while the Sony lens with the 230mm port has equal or better corner sharpness.

I would agree that using really old film ZOOM lenses that only focus to 18 or 20 inches will cause a problem because they need a +2 to +4 closeup lens to focus which then causes an above water problem, modern DSLR lenses or even older fixed focus lenses work fine for splits on DSLR or film.

The attached was taken with a Nikonos RS a 35mm (so called full frame) film camera and an 18mm lens with eight inch dome.

Phil

You are labouring the part in water of this 35mm shot is blurred lol

I think the op got the message he doesn’t need to shoot a fisheye

I wonder why he got that idea tho

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Thank you so much guys...i didn't expect to generate so much interest in the topic, including some lovely picture postings. Apology if this was somewhat discuss previously, i could not find the trend.

I do use the 7-14 for splits, but there are certain things I want to do with fisheye...and I have got decent result with the acryclic 4" dome + 20mm extension or the older panasonic 8mm with the 4" dome without the 20mm extension. I have a DP170N120 and I was interested to see if anyone had tried connecting with a N80-n10 converter, it looks like Wolfgang is already tried and it seems to be working on the surface.

Spermwhale, I am curious to know which is the 6" dome SpermWhale uses with the 7-14mm f2.8 oly? because I thought the only way to shoot this lens is N85-N120, 20mm N120 extension and DP170 (which is a 7in).

Wolfang, I was not aware I could sue a tokina or canon fisheye zooms, I would really like to try these lenses, what adapteur do you use for these lenses on micro 4/3 system.

Thank you.

I used to shoot the Panasonic 7-14mm that works with the nauticam 6”

I believe that the Olympus lens does not fit the port

The zen works fine though?

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Wolfang, I was not aware I could sue a tokina or canon fisheye zooms, I would really like to try these lenses, what adapteur do you use for these lenses on micro 4/3 system.

 

Thank you.

Hi vagabond,

I have decribed it already here, both with Zen DP170N120 and the Nauticam N120 140 minidome:

http://wetpixel.com/forums/index.php?showtopic=62560&hl=

http://wetpixel.com/forums/index.php?showtopic=62974&hl=

I prefer now to use the Metabones 1x Smart adapter with Canon 8-15mm over the 0.71x speedbooster. The angle of view at 8mm is like the Zuiko 8mm fisheye (Subjectively, I cannot see a difference in image quality between the Zuiko 8mm and the Canon 8-15mm when used at 8mm either with the DP170 or the Nauticam 140mm minidome), but when you zoom out to 15mm the diagonal angle is approx. 85 degree, similar to a rectilinear lens at 12mm. While the 34.7mm extension works as it is with the 0.71x speedbooster, using the 1x adapter requires a 3D printed extension collar for the Nauticam Zoomgear - in case you want to use it, I will send you the files (for 1x adapter and also 1x adapter plus 1.4x Kenko teleconverter).

I regard this the perfect WA solution for MFT camera, but of course this is a matter of taste and people have different preferences.

I have tested the 30mm extension form Unterwassercamera.at with the Zuiko 8mm and was very satisfied (Actually this extension was custom made for me by Manfred Werner, the owner of this shop). I did not test the Nauticam 34.7mm extension with Zuiko 8mm underwater yet, because the Canon 8-15mm became my favorite WA lens and I did not use the Zuiko 8mm (and also the rectilinear Pana 7-14mm that I used quite often) since then (but above the water there is no vignetting - difficult to imagine how vignetting would be produced upon submerging...).

I do not have much experience with split shots so far, so cannot comment this issue. I guess whether rectilinear or fisheye is also a matter of personal preferences and the situation...

Wolfgang

P.S.: I have a used Tokina 10-17mm for sale at a good price, extension collars for Zoomgear for using with 34.7mm extension and Metabones 1x on MFT camera are included: http://wetpixel.com/forums/index.php?showtopic=62911&hl=

This is the Zen port chart: http://www.jaredparsons.com/portchart/zen-only/by-combination-group/nauticam-n85/

the Oly 7-14 is large dia so you ave to place camera in housing first, install lens from front then install port. You can see in the port chart you need a 60mm N85-N120 plus a 20mm n120 extension ring. If you already had a 30mm N85-N120 ring you could use that with 50mm extension to save buying another adapter.

All, thank you so much for this very valuable information. You gave me more information here and so promptly that any vendor in the US i have contacted. Thank you again. I ll review in details also the previous postings. Happy Shooting

For most applications I prefer the 8mm with the Nauticam 140mm port with the 17mm extension.

Thank you Phil for the great example pictures of the 8mm + 200 dome and 7-14mm + 200mm combination.

I want to upgrade from my Pana 8mm + 4.33" mini dome. I am struggling between the Oly 8mm + Zen 170mm or the Pana 8mm + Nauticam 140mm.

Could you please also show some examples of the Oly 8mm + 140mm combination.

Why to do you generally prefer this setup over the other ones? Is it because it is a bit easier to travel with and you can get closer for macro-wide angle images? Does this setup also require extra caution regarding curved water lines as you described above? Thanks a lot.

 

Thank you Phil for the great example pictures of the 8mm + 200 dome and 7-14mm + 200mm combination.

 

I want to upgrade from my Pana 8mm + 4.33" mini dome. I am struggling between the Oly 8mm + Zen 170mm or the Pana 8mm + Nauticam 140mm.

 

Could you please also show some examples of the Oly 8mm + 140mm combination.

Why to do you generally prefer this setup over the other ones? Is it because it is a bit easier to travel with and you can get closer for macro-wide angle images? Does this setup also require extra caution regarding curved water lines as you described above? Thanks a lot.

Here's a link to some pics: http://wetpixel.com/forums/index.php?showtopic=60087

What's your reason for upgrading? I have the 8mm Pany used with the Zen 100mm dome and It's sharp except for the very corners. Here's an example:

I painted on some lines to show where the corners are a little soft - right side is cropped off as it's open water in any case : Is this what you are seeing I'm also wondering if this is typical of the Pany 8mm and if the Oly lens would be an improvement?

There's also a review in UWP magazine #87 of this lens/port combo.

Answer to World.explorer questions. Going to the back issues in uwpmag.com again, a free PDF download I have the following reviews.

Issue #64 Pana 8mm N-4.33, #77 EM-1 review with P-8mm and Zen 100, #93 Canon 8-15mm with Zen-100 and #97 Oly-8mm with N-140.

The reason I prefer the Nauticam 4.33 and 140mm for the 8mm's (P & O) is because they also work very well with the outstanding Olympus 12mm F/2 a favorite lens of mine for models and candid portraiture. I have attached two photos using the 12mm.