Waterhouse Stop Assistance

[seabee1999]

Good day to all, after reading a few posts over the past month, I decided to make a single element soft focus lens. The lens I used was a 77mm (~3") magnifying lens I found at the 99 Cent store close to my house. I used an old filter ring to encase the element and glued it into a piece of black PVC. I already had a shutter (Shanel 5A with retaining ring) and used a black rubber cap with some hose clamps to hold everything in place. I just now took down my rig and everything works well and as it should.

As the title suggests though, I'd like to place some Waterhouse stops in the PVC barrel. I have been searching the threads for a long time as well as Google on simple ways to make these kind of stops but really haven't a step by step method. So with that said, if someone could and please, if you have done this process, share with me how you would do this and explain very simply from start to finish that would be greatly appreciated.

Thanks again for your time.

R/
Dave

[Steven Tribe]

I hope the lens has at least 2" of PVC barrel in front of it?

If you want the full "distortion" when it is fully open, you need to make two framing rings either side of the waterhouse stop slot that you are going to cut very near the front end of the barrel. These two rings could be cut from the PVC tube you have used for the barrel! They only need to be a few mms wide, but wider cut rings would be probably easier to make and wouldn't cause any problems. The width of the slit in the barrel has to be quite near that of the material you are using for waterhouse stops. You should cut (saw) exactly halfway through the barrel.

The two rings you have cut off are cut across and shortened in circumference so they will just fit inside the barrel. They will have a natural spring in them so can be glued in place both sides of the cut slot.

The easiest kind of wh stops are made from good quality black card, whch is available from hobby shops. Use nail scissors to cut the holes and use sandpaper (around finger or pencil) to clean up the cut.

Remember Focal length devided by diameter of the hole is the F value of that stop!

I have looked at the card material I have used to make duplicate WHS for original ones which I will not risk taking out of the house and their quality is 180 g (180 g per sq meter?).

[LabRat]

The beauty of your situation is that you are not trying to restore a nice antique lens that requires a specific type of stop, so you are free to use your imagination...

There's the old waterhouse wheels, but the wheel itself might get a little big depending on the lens diameter/max stop... Then there's individual slide-in stops, that require much handling in the field... Then there's finding an old lens barrel that has a working iris, and maybe a shutter too...

If you are asking about how to make stops, here's an idea... The idea of making heavy metal traditional stops that require metal shop tools, is limiting without the shop...

A EZ way to cut the different diameters on your kitchen table is to go to a good art store and buy a compass cutter (which is a knife on a drawing compass), and cut different diameters on materials that will cut well with a knife, such as thin sheet plastics, thin brass sheet shim stock, papers, very thin aluminium sheets/foils, old fogged sheet film, etc... (I'm still using a thin aluminium piece of dryer vent material, or even a beer can... The cutter will go through these quite easily...

I'm also thinking here about photographing a black disc on a white back background with a rollfilm back on a LF camera, where you would measure the disc on the GG and shooting the right sizes as you go for the different f stops, then developing the film (with the blackened outer circle and clear inner circle), and making a slot in the barrel for the strip of film to slide through (like an old filmstrip projector) with the different openings and the film allowed to roll up on the ends... (Hey, this is a simple lens, right!?!!!)

Put on your thinking cap... Improvise, seabee, improvise...

Have fun!!!!

Steve K

[seabee1999]

Thank you both for the help thus far. The point where I've been stuck at is whether or not to have a backing ring for the stop. Thank you Steven for sharing that piece of info. I have a cap I can cut a small ring out of and glue it in place. The stops themselves I plan to use some extra dark slides I have laying around. I figure that my current aperture is around f/2.8. If I place the ring inside, it'll be around f/2.9. My hope is to have stops from f/4 - 16.

Steve, I'll have to look for that hobby knife your talking about. I tried to make a pattern piece already with scissors but didn't have much luck with that.

Thanks again for your help. I hope I can complete this and get an image up shortly.

R/
Dave

[Steven Tribe]

2 rings. one in front and one behind the stops. You will never be able to shorten to the exact internal diameter, so make the two small gaps are at different positions when mounted.

Metalwork with thin metal is not a very safe with hand or machine tools. Always clamp the material.

[AtlantaTerry]

If you want to purchase pre-made metal rings with holes look for inexpensive Step Up or Step Down rings on FleaBay. Or use adapter rings made to connect Cokin devices to lenses - also cheap on FleaBay.

Yes, these rings with holes are not accurate, but heck we are talking about a 99 cent lens!