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View Full Version : M67 Extension Tubes - do they exist?



Interceptor121
April 8th, 2012, 09:17 AM
I have an epoque housing for my Sanyo Xacti HD2000, both bought second hand or ex display
The housing has a 67mm thread that I use to connect an Inon UWL100
I recently tried a 10bar 67 to AD adapter to connect an Inon UWL105AD that is a much lighter lens however the back lens protrudes and I can't use the adapter
I have therefore thought about an extension tube 67 to 67 but nobody seems to produce it, the alternative would be to get a 67 stepdown ring coupled to a step up ring back to 67 to add the 5mm I need in order to use the 10bar adapter and avoid the back of the lens touching the port
Has anybody tried anything like this? Also will the anodized aluminum used in those rings resist salt water??

I know the camera will not vignette as it has a 44mm lens and attaching the lens manually results in no vignetting so no concerns there

bvanant
April 9th, 2012, 02:09 AM
I have used a 77-67 step down coupled to a 67-77 step up to put some external diopters onto an old Inon port. Certainly the anodized Aluminum withstands at least 50 or more dives. Alternately get a cheap 67 mm filter and knock out the glass. That should get you both male and female threads if I understand what you are getting at.
Bill

Interceptor121
April 9th, 2012, 04:59 AM
Yes bill you understand exactly what am getting at. I will try and get the rings in plastic I gather if I get the cheapest probably that will be the case. Then I have to figure out the alignment of the lens in case there is marginal vignetting with the camera shooting 16:9 maybe it is not even needed

Update I ordered a couple of Kood step up and step down will let you know how it goes

Interceptor121
April 14th, 2012, 02:35 AM
OK so the combination 67->62 + 62->67 + 67 -> AD works and there is limited vignetting however the corners are really soft at least in air where the lens is near to fisheye. Maybe I can try it in the water to see what happens but I doubt it will work well

Interceptor121
May 7th, 2012, 12:05 PM
OK back on the experiment. I am now going to try with a 67 mm filter and try knocking the glass

I have tried putting the lens on the port and there is no vignette. With two rings there is vignette very mild in water so with one filter should be just right.

We will see

Interceptor121
May 18th, 2012, 05:58 AM
Great advice Bill. I got an UV filter 67 knocked the glass and now the lens is closer to the port so I get just a small shade outside the water
I have not tried it in the water but the image outside is sharp so this should work very well indeed


I have used a 77-67 step down coupled to a 67-77 step up to put some external diopters onto an old Inon port. Certainly the anodized Aluminum withstands at least 50 or more dives. Alternately get a cheap 67 mm filter and knock out the glass. That should get you both male and female threads if I understand what you are getting at.
Bill


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