August 8th, 2005, 06:06 PM | #421 |
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Matthew, I'd tried doing the capillary method, and found a couple of things. If I had a gap made by dental floss (separating the glass), I could dip one edge of the "sandwich" in melted wax, and use a hair dryer to warm up the rest of the glass, which would draw the wax up. However, it would only rise an inch or so, before gravity seemed to hold it back, so laying the sandwich over at a 45 degree angle would let the wax climb all the way. If bubbles formed, I'd focus on that area with the hair dryer, and could use heat to actually move the bubble up.
With aluminum foil separating the glass, the wax travelled up the glass much more easily, but I lost the ability to eliminate bubbles with heat manipulation. Heat from a propane torch didn't solve anything either. Seemed like dental floss was the ideal thickness, and if beeswax is "clearer" maybe that's not a bad thing. As for cooling, I'm having better luck with Oscar's method. I believe having the excess wax surrounding the glass helps keep a more even reduction in temperature, so that all the crystalline activity during cooling stays more uniform. I suspect it's the uneven cooling process that creates the stratification we keep encountering. And while the capillary method is cleaner, it's also the most suseptible to temperature change across the glass. Also, I've found with rapid cooling (dropping the molten wax/glass sandwich into a cold bucket of water) results in a clear, yet solid wax. So your rapid cooling of the beeswax may not be an accurate indication of it's diffusion properties, or its crystal size. |
August 8th, 2005, 09:27 PM | #422 |
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Interesting. Oscar, your method probably is best but I'm still going to experiment more with beeswax instead of microwax because I geniunely have found the grain to be finer. Maybe it's just me, though.
Glen, I've had no issues with bubbles using capillary action if I hold the glass straight. I heat the wax to the same temperature as the glass (sometimes heat the glass a little hotter) and it takes maybe 20-30 seconds for the wax to rise all the way to the top, at the longest, and the wax is still totally liquid and at a similar temperature throughout at that point so far as I can tell. The hotter the glass, the fewer waves in the wax and the faster it rises. I've been using aluminum tape and double sided scotch tape and stacking to various thicknesses for the spacers. My cooling method was just "throw it in the freezer" which probably resulted in the problems I had, but microwax didn't have those same problems to the same extent. I think both can come out okay, beeswax is just much more sensetive to uneven cooling. I tried dropping the wax into a bucket of water, but water mixed with the wax before it cooled. Do I need to seal anything off or should I just drop it in? I figure it's worth a try if the water is cold enough. I'll try slow cooling, too, since that worked for me better once before. Anyhow, the results are quite good so far except for the waves in the wax, even without a condenser. (My current condenser is too strong and results in areas being distorted/out of focus, unfortunately, but did help with light distribution.) Edit: I just tried slow cooling and everything worked great. I used a thicker spacer (twice the thickness of aluminum tape) and it helped a lot, too. I'll post some results when I get back from vacationing in California in a week. Edit 2: A few random shots (camcorder tethered to my desk unfortunately and lens a bit OOF): http://home.comcast.net/~kittyluv/new1.jpg http://home.comcast.net/~kittyluv/new2.jpg No condensor, but I'm getting there. Last edited by Matthew Wauhkonen; August 8th, 2005 at 11:07 PM. |
August 8th, 2005, 11:07 PM | #423 | |
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Quote:
I'm waiting on some 1.4 micron aluminum oxide and a free day before I make my new run(s) at the project. I'll be doing another microwax series of tests and applying the 1.4 grit to my 3 micron ground glass too see where that gets me. Got a pair of 97FL, 50mm PCX lenses, too :D - jim
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August 8th, 2005, 11:11 PM | #424 |
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I believe I had ice in the bucket -- no water made it into the sandwich that I could tell, but the wax was clear and hard. Not what I'd expected. Now you've got me interested in the bees wax. I wonder if it wouldn't be a bad idea just to heat small portions of these waxes on glass sheets, and do a simple analysis on their grain, and then do combos to see if that has any effect.
I do think that slow cooling allows the crystals time to orient themselves, resulting in finer grain. My best results have come from dropping the wax temperature to just above melting point, and at that point to turn off the heat. I suspect it's the "crossover" time from liquid to solid that does all the damage, and if it can be stabilized just before going solid, I think it improves its chances. (Of course, it doesn't hurt to burn some extra candles and do some ancient chants -- if nothing else it helps keep the wax from piling too high.) Let us know when you get back from vacation. I've never had so much fun with such slow progress before! Glen |
August 8th, 2005, 11:11 PM | #425 |
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Tell me how the condensers work when you try them out. I bought two of different focal lengths but they were too strong, so I need to buy two more and those sound pretty good.
Yes, the light loss is probably one stop beyond what I experienced with microwax (beeswax is more translucent than micro-wax, though, so it's not that bad that it's so very thick.) Anyhow, the thicker wax is a bit softer maybe but it's fine for my current purposes. It's the first "flawless" screen I've made and it was easy to make, and given the fact that I'm using an 18 dollar macro lens, I'm not expecting perfect quality. Edit: Here's a picture showing that it resolves decent detail: http://home.comcast.net/~kittyluv/new3.jpg I had to adjust contrast quite a bit to get enough contrast for the text to appear since I shot this quite poorly, and the lens being at f1.4 and book being close the DOF was so shallow that only a few words are in focus. Yes, it looks horrible, but the detail isn't bad. I'm encouraged. |
August 9th, 2005, 12:07 AM | #426 |
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Matthew,
It looks to me like you put a condenser between the GG and the lens? It's probably too strong. What is the focal length? Quyen |
August 9th, 2005, 12:31 AM | #427 |
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Here's the sad part: I'm not using a condenser in these pics. The issue is related to the cheap macro (Asian brand off ebay) and lens being at f1.4.
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August 9th, 2005, 07:53 AM | #428 |
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To clear things up...microwax is at leased 2x finer than Beeswax or Paraffin. The reason that Matthew has more grain with microwax is either because of too much/long heating or uneven cooling, or it's not pure microwax, like a mixture for moldings.
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August 9th, 2005, 10:15 AM | #429 |
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Sonava...I bought those Asian macros too. What power were you using? Looks like I'm just going to need the 4+ and 2+ or maybe the macro, but I haven't seen distortion like that yet...geez. I guess the old saying's true.
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August 9th, 2005, 12:43 PM | #430 | |
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August 11th, 2005, 09:27 AM | #431 |
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You guys don't have the worry...the macro lens isn't THAT bad. The first two pictures are pretty indicative of its distortion, the last one is from a book that's slanted both vertically and horizontally shot in macro at 50mm f1.4, so of course the depth of focus is so shallow that only a few lines of text are in focus making the rest look horrible. I just wanted to get across how much detail was coming through: a reasonable amount.
I'll post some more results in a week or two, but it's not that bad. The macro lens is pretty horrible compared with century optics or whatnot, I'm sure, but it's not as horrible as it looks. I'll be using it for some upcoming projects, working around its limitations, but when I move on to something that has to be good, I'll be replacing it for sure. Oh, and San Fransisco is freezing. The food's great, though. |
August 30th, 2005, 06:21 PM | #433 |
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I started experimenting with my microwax glass again. I put the GG in my double DV camera system (two DV camera's filming the GG) for a higher resolution test.
I had to make two improvised macro lenses which didn't work out well enough. However, these first test show that the microwax is still pretty much grain free at a resolution of +/- 720 X 1010 pixels. http://s01.picshome.com/a3f/waxd3.jpg Most of the visible grain in this frame-grab is video noise. You can see the left part of the frame (left DV camcorder) is a bit out of focus or something. I really have to fine tune all the four lenses I use to make a better assessment on the quality of the microwax glass, but it's a start. |
August 30th, 2005, 06:41 PM | #434 |
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Nice job. Higher res pics like this are always so much more useful.
Oscar, I was at IKEA the other day and thought of you. I'm glad you can share in an American institution like that. Since you are taking pics of your house in France, I'll have to take some pics of our beach house with my adapter once my microwax is done. You know, some of the houses in my city are over twenty years old! |
August 30th, 2005, 08:59 PM | #435 |
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Oscar, yes I saw the noise, but wow it looks great.
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