Just a quick one for you guys:
1.open WORD, draw 10 circles, fill in with gray (5, 10, 15, 20, 25 etc) and print on transparent film. Cut to fit the size of your filter, or leave as square and mount on UV (or other...) Enjoy your CENTER GRAD ND (and say "buy-buy" to "hot spot")
2. Photograph the above in B/W on a medium camera and use the neg.
3. Buy it and move on. (your call)

Looks good Oscar - remember in low light for some reason there seems to be more grain visible. Dan has found a way around it and the G35 guys have too. Keep searching!

Cool... day to day its better and sharper... Love your hard work.

Thanks Daves and thanks Dan for the filter trick, I'll try it. It's like an inversed diaphragm. Maybe I can put it somewhere inside the tube, to make it in independent from the lenses you put on the adapter.
The better I can get rid of the hotspot, the thinner the wax can be. The thinner the wax, the sharper and brighter the image. That's what I've been doing these day's. I now use a wax layer as thin as the thinnest tape I can find.

That looks very nice Oscar!

I want to see footage :D

Oscar: Good job!

Bear in mind that using a ND grad filter is still just a trick. I suggest trying to keep as much light as possible and get an even distribution using the right thickness of wax combined with condensers.

If you do decide to make your own homemade ND grad filter and you want to be more precise, take a framegrab from your camera pointed at an out-of-focus white wall. Bring that in Word or Photoshop and place the various grey circles accordingly.

Footage Jim? Rain on leaves: http://s01.picshome.com/a48/rain.jpg

Frank, you're right, the condenser I'm using now is very very good. (very thin too, so not much extra space and weight) So I'm happy with that for testing right now.
I've been trying a new technique yesterday, but didn't work just yet. I used wax used by goldsmiths, which are wax plates at about 0,6mm thickness. I put it between the glass and melt it with a weight on top. I didn't get bubbles or dust, but the structure wasn't right. It would be the easiest method if it worked, so I'll try it again.
Frank, Jim, are either one of you still waxing anything besides your hair? Did you get similar results, I can't seem to find much footage of your tests.

Waxing my hair... that's good.

I don't have footage up because I never got to a place where the wax surpassed what I'm getting with 3 micron aluminum ox. Frank has posted some stills that made me a believer, but I've yet to see actual moving footage from a wax adapter (under a variety of conditions, not just indoors under optimal lighting) that was really convincing. And the process of obtaining a hair free, abnormality free wax layer thin enough to produce excellent results proved so elusive that I gave up.

I've been shooting with my aluminum ox setup for a few months now. Give me some time and I'll post full res DV footage from that as a point of comparison.

- jim

<<I've yet to see actual moving footage from a wax adapter >>

Didn't you see the Guerilla35 footage? (I'm joking because we don't know if it is wax and the footage is compressed.)

I'm making an improvised rail to put the tube on with the test wax GG moving steadily and see what happens. I'm sure there will be a bit of a vage structure visible, but I know I can get it better. It has a lot to do with cooling techniques.

Well, cooling technique, cleanliness of the surfaces, lack of dust/hair, in short, too much for me to handle at once each go around. The thinner the wax layer, the more evident the surface anamolies (anomalies? can't ever get that right without m-w.com).

I was never able to get a sufficiently perfect surface that was simultaneously thin enough to surpass the optical qualities of 3 micron aluminum ox -- i.e. finer grain and comparable/beter light transmittance.

Seriously, I'm not posting this to be a naysayer -- my hat is way off to anyone who can get it done well and I would also buy one if the results prove to be repeatable.

Meanwhile, I do have footage of my "near perfect" microwax results. I'll be posting them and the 3 micron footage sometime in the next week.

- jim

So Oscar, where (and what brands etc.) and what kid of equipment did you
get here in Holland? I may give this a go myself...

Rob, 'De Kat' is the most common brand for artist (chemical) supplies in Holland. They only have Paraffine and Bees wax, so that's what I used so far, sometimes mixed with the top layer of candles.
You can get it at most artist supplies shops, but certainly at dekwast.nl.

I'll post today if I get some succes in cooling techniques. I think it's just like steel, a knife isn't of any quality if it isn't cooled don't properly.

Jim, I'm very interested in you results. Just a frame-grab would be nice to compare the two techniques. (I can see the difference of video noise and static grain anyhow.)

Frames:

http://ideaspora.net/35mmadapt/waxgrabs/0.jpg

http://ideaspora.net/35mmadapt/waxgrabs/1.jpg

http://ideaspora.net/35mmadapt/waxgrabs/2.jpg

http://ideaspora.net/35mmadapt/waxgrabs/3.jpg

http://ideaspora.net/35mmadapt/waxgrabs/4.jpg

Jim, those look pretty good, a little gray, is it true you only have 'disturbing' grain on the edges? I mean, the very soft grain can be removed with the lowest setting of a de-grain filter without losing detail. (Looking forward to your aluminum ox GG)

I improvised a rail in front of my camera so I could shoot my cat again. (He's still alive.)
http://s01.picshome.com/a48/fifa3b.jpg

Tests showed that putting the melted wax in the fridge wasn't any good. The best method so far to me is to melt the wax in a aluminium cigar case, put the glass on the bottom with one piece upright (taped together on one side). Vibrate the air out and then flip the other side (with spacers) on top. vibrate some more (just put the electric razor against the side of the aluminium box) and let it cool down. This way it cools evenly.