Microcrystalline Wax Techniques?

[Ben Winter]

Wayne,
You or someone else was talking about an "aerial image" that appeared through the optosigma glass, i.e. the original image came through and cancelled out the DO, or something to that effect...it doesn't look like any of that is going on here. Is there something that you did to prevent that from occuring? I used my optosigma and I didn't have any problems either.

[Wayne Kinney]

Ben,
It happens more on bright objects (like the led of the speaker in the thread above). Im very picky when it comes to quality, I can see the effect in the picture with the cat out of focus, the cats nose....Basically its not diffusing the light enough. Glen has proven that he does NOT get this problem though, so I think he is making excellent progress.

Either way, I good GG should NOT let details through the glass, this only goes towards reducing the 'shallow DOF' effect, which is the whole point of the adapter.

Imagine this, a scale from 0 to 100. 0 is a completely transparent peice of glass, 100 is completely diffused. If you gradually go from 100 to 0, you will start with shallow DOF to a complete aerial image. So as you get closer to 0, the less 'shallow DOF' you have.

I would say the optosigma glass was around 90 to 95% on this scale, and i want 100%.

Wayne.

[Oscar Spierenburg]

Wayne, I wouldn't confuse this issue too much with quality. Did you see the Guerilla35 footage? It clearly has allot of light going through the GG diffusion, but it seems to be collected by one or two condensers. Those highlights give a nice 'over exposed' look to it.
However, too much is terrible of course, but it looks like Glenn has got the right thickness. I made my own diffusion example on the this image: http://members.chello.nl/a.schultzev.../filterWax.jpg

[Wayne Kinney]

Oscar,
OK perhaps 'quality' isn't the word, but I see it as being an incorrect and untrue image. It gives a 'haze' effect to the image in the 'out of focus' area's. Your image doesn't address the effect im talking about, since your glass is right flat up against the image behind it.

Example, take Glen's image of his glass in front of the green led of his speakers, that it properly diffused and how it should be. If i do the same with the optosigma glass, you get the green diffused light the same as glens, but also you see the focused light as well mixed in like two images mixed together. This means that the led will never go out of focus properly.

It just gives a strange and 'untrue DOF' effect.

I know this is a wax tread, but the same applies to a wax layer that is too thin. Same or similar effect.

Wayne.

[Wayne Kinney]

Just 2 images to back up what im saying:

http://homepage.ntlworld.com/wayne.k..._problem01.jpg

http://homepage.ntlworld.com/wayne.k..._problem02.jpg

As you can see, the glass lets through far too much arial image. You should NOT be able to see the lamp through the glass like this. When in the adapter, the result will be this lamp with a blury mist/haze effect around it, instead of being properly out of focus.

I hope I have made myself clear.

Wayne.

[Ben Winter]

ahh, okay, that helps a huge bunch. I had thought previously that you were referring to that effect while the ground glass was in the adapter being used. I didn't know you meant just holding the gg in general practice. Thanks.

[Wayne Kinney]

Ben,
Read it again,
I did say what will happen when the glass is in the adapter:

When in the adapter, the result will be this lamp with a blury mist/haze effect around it, instead of being properly out of focus.

Wayne.

[Ben Winter]

Ahh, just proves I'm an idiot. Although i wasn't getting that at all with my optosigma, which is why I had trouble understanding. Perhaps I had GG of a different batch? Or maybe like you said you want that extra 5% that I probably can't notice all too well anyway.

I think eventually I may try the microwax technique just so I can say I've been the GG, vibrating, focus screen and wax routes.

[Wayne Kinney]

To be honest ben, im also starting to think my glass is from a bad batch possibly.

Then again, my own ground glass i made with 1000 grit aluminium oxide, had the same problem, although not to the same extent as the 1500 grit optosigma glass.

I also ground a glass with 600 grit AO, this glass does not let any aerial image through at all, so from looking at these 3 glasses, I concluded that the finer grit you use, the more aerial image comes through.

It does look like microwax is the best solution for static, just a bitch to get right from the look of it. I think the wax suffers from the same problem if the wax layer is too thin, but it looks like Glen's glass is great, although he said he has grain.

Wayne.

[Frank Ladner]

Wayne: I just wanted to confirm that I think you are correct regarding the aerial image and grit size. I am working on a spinning adapter and I opted to use a larger grit to cut back on the aerial image / hotspot. As long as the adapter spins/oscillates quickly enough, large grain is the way to go in my opinion.

[Wayne Kinney]

Hi Frank,
thanks for the input there. Your also working on a glass spinner, right? Would you be willing to share your experience so far? you method for spinning the glass? Looks like its only me and you working on a real glass spinner. May be you could reply on my thread here:http://www.dvinfo.net/conf/showthread.php?t=50507

Thanks,
Wayne.

[Oscar Spierenburg]

This whole issue only applies to wax when you have a too thin wax layer, or you have the wrong wax. I've tested an expensive molding wax by silver/goldsmiths. It was very fine, but had some kind of mixture that greatly reduced the diffusion of the wax. It was too bad, because it comes in thin wax films, so you just put a sheet of wax between the glasses and heat it. The excessive wax is just pushed out (when you put a weight on top of the glass)No bubbles and no dust. I forgot about this, but I'll take another look at it, see if I can make wax films with microwax.

One other thing: what kind of wax are you using Glenn, some of the images you posted seem to have a bigger size of grain than microwax.

[Glen Hurd]

It's microwax. I ordered two varieties. This is the softer version. I've heated them up several times (I'm convinced the wax I keep getting -- from different places -- has dirt embedded in it), so I try to clean it by heating and letting the particles settle, after which I scrape them off. I'm glad you think the crystals are larger than expected as it gives me hope that I'll find a source of wax that has a finer structure.
I understand Frank Ladner was getting his from SPWax, or something. But now he's looking at rotating glass adapters? Did you end up with no luck on the wax adaptor, Frank?
Who, besides Oscar, has a satisfactory wax rig? Jim?
Another issue may be that my wax is so thin, that it's showing more crystal structure than we're used to seeing. I am only losing 1/3 stop of light.
I downloaded Jim's recent video, but found it hard to evaluate grain since most of the footage was dark. I like the simple tests (as Wayne used with the LED and the graph lines).
I'd never known the difference between wax and optosigma until yesterday.

Gotta go . . .

G

[Oscar Spierenburg]

Glen, in my experience too much reheating resulted in more visible grain, but certainly a too thin layer shows more grain. I did not use a thinner layer than aluminum foil, with just 1 or 2 stops light-loss.

<<<Who, besides Oscar, has a satisfactory wax rig?>>>
How about the Guerilla35 and the MovieTube.

[Jim Lafferty]

Back after having the neighbor's dog chew through my cable line :(

WRT my footage being "too dark" -- I'm sorry, but that's a GL1 for you. I shot it with an overhead 60w light and that's pretty much it -- no windows in this room. I can get some light spilling in from other rooms but it's largely inneffective with a cam that performs so poorly in low light. I'd pump up the gain, but then with it the grain goes up, too. Guess I could step outside, but then in a sense I almost want dark footage to see what the image looks like in "less than ideal" circumstances.

At any rate, I've got more wax tests in the way and will do a variety of different lighting scenarios.

I don't yet have a satisfactory, working wax glass, to answer an earlier question. Frankly, the 1.4 micron alumina GG I have was such a comparitvely easy job to produce (and reproduce consistently), that I've been half tempted to get 1 micron slurry and see if I can call it a day.

It's just that Frank Ladner and G35's footage looks so damn good I can't accept defeat that easily :D

- jim