Solving soft corners with Inon UWL-100 + dome

After some time just reading this great forum I thought that I might contribute with something in the D.I.Y-area.

I have an Ikelite housing for my Canon G9 and was interested in wider angle of view. After some research I decided on the Inon UWL-100 with the dome. I also got the short wide-port that Ikelite sells.

When I got the lens I couldn’t wait to try it in the ocean so I decided to try it in the bath tub.

I was very disappointed. There was very smooth corners and some minor vinjetting.

I decided to fix the problem. The solution was a new homemade port for my lens and housing.

Here are some photos showing before:

The port and the attached to the port:

Picture after the modification:

You could visit my website for some more info.

/Martin

Excellent job! Impressive.

A brilliant solution Martin. Thank you for sharing your achievement with us. Have you considered making your port available to the G9 Wetpixel community? If you ever do, my son and I will take one each!!

Ikelite should really build a port that offers this kind of performance.

Not to minimize your efforts, Martin ... but if it is that easy, it is surprising that the "specifically-designed-for-exactly-these-kind-of-wide-angle-adapters" port performs so poorly.

Kudos to you once again.

... we're a resourceful lot ... scuba itself is a pretty good hack!

Nice work Martin!!

Only downside seems to be that You cant change te lenses underwater anymore?

Nice work Martin!!

Only downside seems to be that You cant change te lenses underwater anymore?

You will have to do it really fast...

That is one negative thing with the port. You are stuck with the WA the whole dive.

I could maybe make some more ports but I cannot guarantee that it will be watertight... The dimensions of the UWL-100 are critical since the port will seal against the lens, and I don’t know if it has changed over the years. I could post the critical dimensions so you could verify that it is the same size.

The port could quite easy be adapted to other cameras. If the threads are the same on the housing the only thing I would have to change is the distance from the lens to the housing. The WA lens could not be closer than 2-3 mm from the outside of the housing. The G9-lens is flush with the outside of the housing at its widest settings

At the moment I have not tried it deeper that my bath tub and I have no equipment to do a full pressure test. It is designed to handle the pressure but testing it would be nice.

/Martin

You will have to do it really fast...

... or be David Copperfield !!

But seriously Martin, if You get it tested or dive with it somewhere deeper than bathtub, be sure to let us know!

Im seriously considering this as a great alternative to Ike port..!!

Oh, your product has professional quality!

I have a question:

The lower pict (after mod) shows the narrower angle of view compared with the upper pict(before mod) about 75%.

The distance between the lens and the corner of pict are different in the two situation.

So it is not the real compariosn.

i think

without the modification, narrower aperture (incresing F number) may make the coner of pict sharp

and slightly zooming up may cansel the vignetting. (Or the cropping the upper pict ..)

I hope your mod. results a good pict under the sea. Thank you.

I have a question:

The lower pict (after mod) shows the narrower angle of view compared with the upper pict(before mod) about 75%.

The distance between the lens and the corner of pict are different in the two situation.

So it is not the real compariosn.

It is the same angle of view. The distance from the object might be a little different. The soft corners will be there regardless of the distance of the object.

No, it's not a 100% comparison but the conclusion is the same.

I have many testpictures and I choosed one of them.

i think

without the modification, narrower aperture (incresing F number) may make the coner of pict sharp

and slightly zooming up may cansel the vignetting. (Or the cropping the upper pict ..)

Yes, it will get sharper with increasing F-number but I want to show the worst case senario and that you will get a nice picture even if you need a large apature. Taking WA-pictures here in Sweden with a G9 requires a large apature. The "After" image is also taken using f/2.8

Yes, vingetting will disappear if zooming but zooming slightly on the G9 will move the lens away from the WA-lens, giving you an even worse corner sharpness. You will also loose some of the nice wide FOV.

Attached image shows crop taken with f/8. You will loose almost 3 stops compared to f/2.8 and that is much here in Sweden with poor visibility.

/Martin

Hi there Martin!

First and formost...really nice work!!! looks really prof.

I have read your post both on your homepage and here...and as far as I can see there is no discription on how you mounted the new and improved port on the IKE housing!??

...I too have made my own Inon-AD for my fuji f31 housing..also adjustable horizontally.. but still with the glass !! has the added benefit of making macro shoots even closer due to added distance/magnefing effect..

How did you come up with the (in my world..semi-crazy) idear of removing the glass??

the results are stunning and your currage is beonde me(and probertly many others)...I never thought of getting rid of the glass.

but hey..you live to learne...he he!

Nice job...can't wait too hear about your dive experince with the new port..and othe projekts you might come up with...(had a look at your norwigian home page)

Hi there Martin!

First and formost...really nice work!!! looks really prof.

Thanks! Its alwas nice to hear nice things...

I have read your post both on your homepage and here...and as far as I can see there is no discription on how you mounted the new and improved port on the IKE housing!??

The port is mounted the same way as the old port. You can remove it by turning it counter clockwise. I made the same threads on my port and the same o-ring grove as on the original port. The back of my port looks exactly as the original port.

How did you come up with the (in my world..semi-crazy) idear of removing the glass??

the results are stunning and your currage is beonde me(and probertly many others)...I never thought of getting rid of the glass.

but hey..you live to learne...he he!

The main reason for removing the glass was so I could minimize the distance from the camera lens to the UWL-100 lens. The distance from the inside of the glass to the UWL-100 was about 7-10 mm and that made a huge difference in the corner sharpness..

One other advantage with this solution is that you can make split-images without the problem with some water/air mix between the lens and port. You will also never have any particles between the port and lens.

(had a look at your norwigian home page)

I'm acually from Sweden...

/Martin

One other advantage with this solution is that you can make split-images without the problem with some water/air mix between the lens and port. You will also never have any particles between the port and lens.

That thought immediately occured to me when I read your original post Martin. Presently and in order to take split images I use a thick rubber band to _trap_ water between the rear element and port. Another advantage will be no more infuriating micro-bubbles on the surface of the port or rear element...

I take it your custom port employs o-ring protection between both the housing and port and the port and the UWL-100?

Of course, your custom port will prevent swapping lenes u/w. The prospect of unscrewing and screwing a UWL-100 and dome never thrilled me anyway...

I take it your custom port employs o-ring protection between both the housing and port and the port and the UWL-100?

Yes, there are the original o-ring between the housing and port and then one between port and lens.

The one bewteen port and lens are pre-compressed a small amount to make sure it will seal. A small amount of o-ring grease make it simple to put together. After the lens is in place, just rotate it until it is in the correct position and then lock the lens in place. The ring with M67 threads will have to be removed from the lens. It is the surface behind this that will seal against the port using the o-ring.

/Martin

Martin. I'm not sure I understand how you are able to rotate the lens while maintaining an effective seal between the lens and port or port and housing. I assumed that the dome would need to be adjusted. Clearly I'm wrong... I'd love to see your technical drawings! What gap (distance) have you allowed between the rear element of the UWL-100 and the lens?

Thank you

I have just re-read your last post and having taken a close look at my own UWL-100 I think I can see why you have removed the 'M67 ring' from the rear of the lens. Obviously the six screws which secure the 'M67 ring' interupt an effective seal. So are you are relying on water pressure to hold the lens in place and make the seal? May I suggest that a redesigned 'M67 ring' which incorporates an o-ring groove would be an improvement? If the 'M67 ring were to be replced, a coarser (and stronger) thread could be used. Am I thinking this through properly?

Martin. I'm not sure I understand how you are able to rotate the lens while maintaining an effective seal between the lens and port or port and housing. I assumed that the dome would need to be adjusted. Clearly I'm wrong...

The lens will slide into the front of the port and seal againt the o-ring. Since everything is round, it can rotate freely and you adjust the dome this way. You want the shades at top and botttom. You dont need to loosen the screws holding the dome to the UWL-100 to adjust.

What gap (distance) have you allowed between the rear element of the UWL-100 and the lens?

It's about 2-3 mm.

So are you are relying on water pressure to hold the lens in place and make the seal? May I suggest that a redesigned 'M67 ring' which incorporates an o-ring groove would be an improvement? If the 'M67 ring were to be replced, a coarser (and stronger) thread could be used. Am I thinking this through properly?

No, the lens is hold in place by 3 or more screws (seen on the port-picture) These screws will go into the grove above the M67-ring securing the lens.

Yes, you could design a new ring but that would be too large and it would be impossible to get the UWL-100 that close to the camera lens. It is very tight as it is. You would also need to have an extra o-ring seal, one more thing to take care of.

/Martin

Hi again Martin!

Thanks for the quick response...Sweeden/Norway same same..old danish Colonies..he he!

Never had a Ike UW house so diden't know that it wasen't a "molded-in" port like on the typical pvc/plastic housing for P&S's...!

I like the way you hold the UWL-100 in place...I have coppied that mounting system just with finger screws..in order to adjust the distance to the port!

Inon's AD system is great but I can see the benefit of the "missing" glass as I have had a couple of W shots(with the Inon AD 105) ruiend buy reflexions...might be the camera lince but most likely it's the port glass.

When are you going to share you DIY arm's with us ??

Looking forvard to more on you different projekts...keep up the good work!!

love this feature(the DIY forum) as most "real" gear is soooo pricy...

nice to get some insperation from geek like you and others

I like the way you hold the UWL-100 in place...I have coppied that mounting system just with finger screws..in order to adjust the distance to the port!

 

Inon's AD system is great but I can see the benefit of the "missing" glass as I have had a couple of W shots(with the Inon AD 105) ruiend buy reflexions...might be the camera lince but most likely it's the port glass.

Do you have any pictures of your AD-mount?

The reflections could be from some light entering the port, either from the flash or just ambient light. If you have shiny parts on the camera try to cover then using some black fabric.

When are you going to share you DIY arm's with us ??

When they are finished... Now they are just lying on the shelf waiting to be polished and anodized.

They are nothing special. The construction is almost a copy of other strobe arms. They are made from solid aluminium. Drilled and turned.

Looking forvard to more on you different projekts...keep up the good work!!

I will do my best....

/Martin

Hi martin.

What rottary sistem do you use for proxxon cnc.

You modifed the original rottary or do you buy a new one.

Thank you very much. Excuse me for may bad english.