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Brett Erskine December 19th, 2004, 01:14 AM Joel beat me to it. Go with the T-Mount and then either we could buy our own lens T- mount adapter or you could include one of a few choices with it. P+S Technik sells them seperately but then again they are custom made for the Mini35. I'd recomend you include the right T-Mount adapter according to each order. Throw it in a seperate box if need be. You want to give your customer the closest thing to a out of the box device to make them happy. You dont need to have T-Mount adapters for ALL the different companies out there. Just 3 or 4 of the major players. Anything else the customer can get at B&H.
Look forward to seeing that video. Only then will I personally beable to give you a accurate number as to how much I would be willing to pay.
Joel Aaron December 19th, 2004, 10:50 AM <<<
From a marketing standpoint, I don't think you can compare this to the Mini35, because it's in a completely different league. -->>>
Here's the way I see it. I don't give a ratsbehind what the unit LOOKS like as long as it's fairly compact.
In this case, I think both his devices look BETTER than the mini35. Plus you can slap it right on a DVX100 which is probably the biggest market for this thing right NOW. He may need to add a rod system to help support large lenses.
But with a smaller lens:
http://pictures.care2.com/view/2/717325749
VS. this mess?
http://www.pstechnik.de/datasheets/pics/digital/d_mini35_2_l.htm
The Mini35 is ridiculous on any camera other than an XL2 (one of the sillier looking cameras ever produced in it's own right)
Having said that, there's a guy on another thread that put a static adapter on the front of his XL2 and seems to like it. So that CAN be done TOO. I think Dan's unit is more likely to turn an "on the fence" XL2 buyer into a DVX100 or Sony FX1 / HVR-Z1U buyer.
Additionally you could adapt to a zillion other cameras with inexpensive step up rings. There are some pretty nice under $1k 3 chip cameras out there right now. Great for pre-production trial footage. Remember, that was supposed to be one of the Mini35’s selling points? If it’s not the final product then all it has to be is “good enough”. Does anyone really use these for trial footage though?
Nothing in Dan's posts indicated his unit makes much noise. I thought he specifically mentioned it was very quiet. If it's really noisy that might knock it out. Or I might baffle it because the unit is so compact.
As to renting a Mini35... great if you're in LA or NY go for it. I'm in Phoenix... the 5th largest city and there isn't ONE for rent. So, taking a wild guess here... that probably leaves about 90% of the world's population without a Mini35 available locally to rent. And if 2 days rental BUYS one of Dan's then I feel sorry for the rental houses anywhere other than LA.
In the end it comes down to image quality. If his image quality is as good as a Mini35 or better for a fraction of the price it will sell just fine. If the image quality is too soft it won't sell for $19.95 even if it includes 3 extra knives. ;-)
As to the higher end market... the Mini35 will be either put into obsolescence by units like this one (buy 10 instead of one and do multicam shoots) OR more likely it will be killed from above. The new small company brew HD cameras will drop into the 10 to 25K range like the Drake system. I'll be looking very seriously at those when they happen.
It's safe to say my opinion is the Mini35 is close to dead at it's PRICE at this TIME and there's much more of a market for a low cost unit. Then in 5 years technology may erase that market.
Dan Diaconu December 19th, 2004, 01:19 PM Thank you Joel for your sincere opinion and fare vision.
Noise, image quality, size, weight, compactness, all have been
extensively considered and will be documented soon on the new site
(a rods support for longer lenses and T-mount will be there for all)
(I can not resist though): If anyone will EVER (that's a STRONG statement)
find any better image converter using a GG in motion
(brighter, less noise, less blah blah, etc AND no grain visible not even when the aperture on the SLR lens is set at
16 !!!!!!!!!!!!!!!!!!
HELO!
16!
hence a crispier picture, emulated by another device, you will prove me worthless.
(of course using a different method than mine)
The pictshaaaa is as sharp as the SLR lens can deliver @1.4 or 1.2. (Clips soon)
Keep in mind, please that my drive on this quest was FX1 print on film, for theatrical distribution. That defines a certain market segment.
Can't compromise anything with THAT goal in mind.
Please note that for the Pro35, P+S recommends using apertures no higher then 4-5.6.!!!!!!!!to avoid seeing the grain of GG. Anyone with me?
The unit is $ 28.000 US. Twenty eight thousand.
(have to catch my breath.....huh, that's better now)
I live to set standards, from which (hopefully) all measure.
Been doing it ever since. (this is how I ended up having as many friends as I have........)
Performance. That's all I care and live for. The best that can be achieved. Can I do it better than I did it yesterday?
Am I better than I was yesterday? It will end in the grave. Then I will be perfect and everyone else happy.
(if I was around for money, I would have done something else by now, without irritating everyone ....)
End note:
I already thought of another way to reduce the noise further. (further improvement on the current movement and no mousepads involved)
Dono if I will implement it though.
Too expensive to assemble. But..... I'll think about it...............
Joel Aaron December 19th, 2004, 02:06 PM <<<--
Originally posted by Dan Diaconu : Thank you Joel for your sincere opinion and fare vision.
->>>
Hey no problem. Now buckle down and put a couple together so Obin and I can be the first couple of guinea pigs! Provide us with an upgrade path of course. :-)
No offense, but you're not the first (or 2nd) person to come around here saying you were "this close" to having something people could buy/replicate. I think you're closer than anyone else from what I've seen so I'm hopeful you'll pull it off.
There is one other thing I wondered about your design. Can the battery be replaced if it runs down while on location?
Dan Diaconu December 19th, 2004, 02:29 PM I use NiMH rechargeable. They should last for about 100 hours of continuous use on one charge.
(They last longer than that but I am playing on the safe side)
How many hours or takes or days that means?..... depends on the shooting style. Unless you forget it ON (LOL)
One should have enough time (once a week) to leave them for one hour plugged in.
Daniel Stone December 19th, 2004, 03:42 PM Too much talking, not enough action. Why not show some side-by-side comparison footage, rather than writing a novel about how great the picture is (and how much you love yourself)? I hope Dan's unit takes off and becomes competition for the Mini35. But I doubt it will. At this point, I kind of get the feeling that Dan is looking for compliments from this board, more than input and ideas to develop his unit.
It just seems that Dan's writing about how great he thinks he is and how great the picture is and how some huge producer quickly returned a Pro35 when he got Dan's homemade contraption ... and the 2 guys on here are blindly sucking down what's being fed to them - without seeing any proof.
Show some side-by-side comparison footage, prove me wrong. Then, if the picture quality really is comparable (or half as good as you rant it is), then you'll need someone to design a professional-looking housing. Then you'll have something.
About renting the Mini35 in other cities - you have it shipped. Most suppliers don't charge for delivery time. I live in the DC area and we don't even have one to rent.
Joel Aaron December 19th, 2004, 04:35 PM <<<--
Originally posted by Daniel Stone : Too much talking
-->>>
You're right. I think your objections have been noted.
I do think some uncompressed footage like Brett requested is called for soon but I don't think Dan needs to spend a nickel on redesigning the housing. I'm with Brett on that one too. It looks well designed. Certainly better than the Mini35 hackjob. (sorry, couldn't resist - but it does look like a joke afterthought on a PD-150 or DVX100).
Brett Erskine December 19th, 2004, 04:39 PM Dan Im going to have to agree with Daniel. Your ego needs even more stroking than mine. Show us the goods.
If the sharpness isnt there then thats that. We can always go with my design which works with medium format lenses and a much much larger (clearer?) image on the GG.
See there is always a better design right around the corner so try and keep your comments under control.
We all look forward to seeing the videos.
Leigh Wanstead December 20th, 2004, 03:42 PM <<<-- Originally posted by Brett Erskine : Dan Im going to have to agree with Daniel. Your ego needs even more stroking than mine. Show us the goods.
If the sharpness isnt there then thats that. We can always go with my design which works with medium format lenses and a much much larger (clearer?) image on the GG.
See there is always a better design right around the corner so try and keep your comments under control.
We all look forward to seeing the videos. -->>>
Hi Brett,
Can you direct me to your url which you are talking about in your post? I am interested to know about your design.
Regards
Leigh
Brett Erskine December 21st, 2004, 12:27 AM Unfortunately I dont have a website dedicated to my design. Actually its basically P+S Technik's design but with a 645 medium format GG. But if you want to read more about the advantages of using large GG and MF lenses we extensively talked about it in:
http://www.dvinfo.net/conf/showthread.php?s=&postid=254002#post254002
But this is Dan's thread so I dont want to cluter it with other info. Dan's adapter is much further along than mine and I applaud him for all his hard work. In reality we dont know which one is better and it was unfair for me to say so without knowing for sure. I was making a blanket statement based on the general fact that the imperfections of GG are all reduced when the image is larger as it would be if it used medium format lenses. Even Dan's adapter will be even clearer if it used MF lenses. But perhaps its clear enough already. So my apologies and I take back that particular statement.
Les Dit December 21st, 2004, 01:49 AM I don't think you have to post uncompressed video. At SD res I think you will find 10 megabit/sec media 9 videos will preserve all the grain or lack there of. I used a bit less than that for 720 P and it holds up well. Well enough for HD dvd's too, the industry shows. Take the T2 special edition for example.
So how about a media 9 vid!
-Les
Bob Hart December 21st, 2004, 09:15 AM Brett.
Off-topic. The camera tech who showed me the dove prism also asked me why I was using 35mm still cam lenses when medium format would be so much better.
(He has a store full of medium format stuff he wants to move of course but he made the same point as you do. If one wants HD resolution then one must use the scaling effect of a larger format and gg screen area to reduce the grain proportionately, also the inherently better resolution of the larger format).
Aaron Shaw December 21st, 2004, 09:44 AM Medium format does seem very promising Bob - even with the slightly slower lenses.
How much light do you loose with your system Dan?
Dan Diaconu December 21st, 2004, 10:42 AM No hard feelings,
just hard work.
Use the camera (camcorder)you have, aim at a scene and take a reading (ex: 1/60 5.6)
place a lens and a focusing screen of an SLR infront and take another
reading. ( It doesn't show a loss over 1/3 stop or less here)
Brett Erskine December 21st, 2004, 11:20 AM Check out my link for more info but heres a quick overview:
Expect MOST MF lenses not to open more than f2.8 while in 35mm most lenses open up to around f1.8-2.0. There are special cases for both formats of coarse but these are generally what your going to get in the affordable lenses.
Now I know what your thinking...MF lenses sound like they are up to 2 stops slower than 35mm lenses. Why would someone want to use them...? Well consider this. Because the image they produce on the GG is so much larger you wont have to zoom in with your video cameras lens to see it full frame. And as many of you know if you zoom in on most video camera lenses you start losing stops (ie DVX100 is only a f2.8 at full zoom and a f1.7 at fully wide). So if you dont have to zoom in you just gained back any light loss in the system. Basically your in the same boat in that sense so no additional light loss problems.
Next DOF. DOF is even shallower in MF versus 35mm. The DOF of a MF lens set at f2.8 will be very similar to that of a 35mm lens set at f1.8. So once again no problem there.
Now on to the advantages. Since your no longer trying to capture such a small image on the GG you dont need a diopter anymore. Anyone thats been experimenting with diopters knows that the inexpensive ones have major color fringing problems that severely effect the final image quality. While the achromat diopters work much better but one thats both strong enough and of high enough quality are very expensive. So with a MF DOF adapter you no longer need a diopter. One less piece of glass to worry about.
Next because you have a larger image on the GG in MF you can expect to see a increase in clarity and a image thats less diffused.
Once again Dan's adapter might already be clear and sharp enough so all of this might not be necessary. But if it isnt, I personally feel he can improve his incredible adapter even more by switching to MF lenses. Thru building many versions of a 35mm adapter and watching the footage posted by others online its been my experience that the footage has always been overly soft. To the point its draws attention to itself and wide shots loss some important detail. Try shooting the same shot with and without your adapter to see what Im talking about.
Anyways this is one way to get around that problem but I also believe with enough searching its possible to find right type of GG with characteristics that would allow someone to pull a pretty sharp image out of a 35mm adapter. Look at P+S Technik. They look pretty good. Not perfect but close.
Anyways something for everyone to consider.
Leigh Wanstead December 21st, 2004, 11:20 AM <<<-- Originally posted by Dan Diaconu : No hard feelings,
just hard work.
Use the camera (camcorder)you have, aim at a scene and take a reading (ex: 1/60 5.6)
place a lens and a focusing screen of an SLR infront and take another
reading. ( It doesn't show a loss over 1/3 stop or less here) -->>>
No offense,
Show me the real demo.
Joel Aaron December 21st, 2004, 11:39 AM <<<--
Originally posted by Brett Erskine :
MF - Anyways something for everyone to consider.
-->>>
I know I got pretty excited when I pointed my camera at my Mamiya RB67 GG the first time. I ordered some satinsnowglass gg in that size so I could try it out. I still had vignetting and grain issues though the images did show some real promise.
You may be right, Dan's design with a MF lens and bigger GG might be the ultimate... especially when moving towards HD.
If systems like the Kinetta get cheap enough it may be moot. You can slap a 35mm lens right on those.
http://www.kinetta.com/download/files/kinetta-camera-brochure.pdf
Dan Diaconu December 25th, 2004, 04:27 PM About the preivious "method" to determine the light loss:
Sorry, I did not express the test clearly:
The 1/60 @ 5.6 (or anything else suitable for the avail light) I was ref. to, was the reading on the camcorder /digital still.
The lens I used (and did not see much light loss) was Nikon
1.4/35 and Minolta 1.4/50 projecting the same scene image on the GG.
Camcorder zoom matched the focal lenght of the SLR lens, in both cases.
(so the same amount of reflective light from the same scene
would be compared) : direct reading vs. 1.4/50 lens on the GG.
I am sure a light meter would be more accurate in reading,
but I did not care to find out the actual loss since I do not know of anything brighter than Beattie.
Aaron Shaw December 25th, 2004, 04:35 PM but I did not care to find out the actual loss since I do not know of anything brighter than Beattie.
A holographic diffuser
Dan Diaconu December 25th, 2004, 07:10 PM http://www.globalspec.com/featuredproducts/detail?exhibitId=3781&fromSpotlight=1&fromSupplier=0
http://silver.neep.wisc.edu/~lakes/HoDifLoScat.pdf
http://www.poc.com/lsd/default.asp?page=applications&sub=hdst
http://www.photonics.com/spectra/applications/XQ/ASP/aoaid.313/QX/read.htm
As far as I understand from the above (and other sources)
this is (in simple words) a "linear" Fresnel, used in LCD screens (and other applications) to even out the light from the
(usually two on the sides) light sources found in LCD's.
The light loss (towards the center of the screen with the square distance from the sources)
is precisely matched and compensated by the amount of
reflective surface: the further away from the source, the
bigger the reflecting receiving tip of the prism. End result;
evenly reflected light of a surface from the same linear source.
Did not try them, but I do not envision them transmitting more light
(from a centered light source such as lens) towards corners than the same thing
made specifically for the purpose (such as Fresnel in Beattie screens)
If you find them brighter, side by side measured, let us know.
PS. Same idea used here
http://pictures.care2.com/view/2/836676796
to even out the screen (from 3 LED's) of a "bomb detonating watch"
Dan Diaconu December 25th, 2004, 08:37 PM Merry X-mass, Happy hanukkah and
a happy new year to all members and guests.
(better later then never, I guess...)
Aaron Shaw December 26th, 2004, 03:47 PM Dan,
Unfortunately I do not have a beattie screen to run tests with.
Holographic diffusers can have a trasmittance greater than 90%. I would be very surprised if any GG or screen could match that.
I'm not entirely sure what you mean by a "linear fresnel" but these diffusers produce a highly homogenized light ouput. The direction of the initial lighting is not important. In addition to this you can use these diffusers to redirect the light in numerous directions and shapes. Very cool stuff!
From the POC website (the company who holds the patent):
"Light Shaping Diffusers are holographically recorded, randomized surface relief stuctures that enable High Transmission Efficiency (up to 92%), and Controlled Angular Distribution, while providing high quality Homogenized Light. These fully randomized (non-periodic) structures are non-wavelength dependent and will eliminate moiré, without chromatic aberration. The precise surface relief structures provide controlled angular light divergence, emulating a negative lens.
Standard and custom OEM products are available, including a variety of angles, sizes, shapes, cut-to-print parts, and substrate materials including 2-sided diffusers (PCS), variable angles, color tints, and low birefringent substrates."
Dan Diaconu December 26th, 2004, 05:33 PM Aaron,
I am just as curious as you are to find out the dif (I am sure there is
a BIG one)
Do you get a "hot spot" in the centre? (using a wide 20-28mm lens)
on a 24/36mm surface? (I would be surprised if you would not)
Filip Kovcin December 26th, 2004, 05:43 PM Aaron,
i checked poc site:
http://www.poc.com/lsd/default.asp?page=overview&sub=main
and read what you already mentioned. did you chcecked that more deeply? i'm not expert on this - but which one diffuser is sutable for our GG works - in your opinion? any of the mentioned there on their site, or it shlould be custom made?
thank you,
filip
Aaron Shaw December 27th, 2004, 11:01 AM Dan,
I don't know if there is a big difference or not. It would be great to find out but I just don't have the necessary supplies. I'm not here to say that beattie screens are worst than holographic diffusers so you have to go with one or the other. I'm just passing on some interesting knowledge I've gathered.
From an online article regarding holographic diffusers:
http://www.mdatechnology.net/techsearch.asp?articleid=33
"The holographic beam homogenizer is a thin sheet of material that diffuses light. Placed between a light source and a display, surface, or screen, the homogenizer eliminates “hot spots” (bright concentrations of light) and dark areas, improves transmission efficiency, and redirects light"
Filip,
I'm not sure what would be best. I'm not an expert in this area either. From what I have gathered though I think what we want is a low angular dispersion (less than 10 perent if possible). For 35mm lenses you could probably use their 50mm rimg-mounted diffusers. The other option would be to buy one of their rectangular sheets.
For me, since I am interested in using MF lenses, the 50mm will be too small an imaging surface. I'm going to have to purchase one of their larger sheets. What's great though is that these can be manufactured to anamorphically squeeze the image for you! No need for ANY lens!
Dan Diaconu December 27th, 2004, 12:08 PM I am "digging" into this matter. I will let you know if I find out anything of interest.
Did you check the tech info from beattie?
How they make the difuser and the Fresnel?
Just in case you missed it, it's here:
http://www.intenscreen.com/pdf/focusing_screens.PDF
I am no biased in any way and ready anytime to switch for
better (providing it can be demonstrated to be better for the purpose!!)
Aaron Shaw December 27th, 2004, 12:50 PM Very interesting Dan. I can't tell precisely how or what the screen is made of from that PDF. It seems to be a fresnel made with holographic processes? Interesting...
Anyway, I'm going to be getting a holographic diffuser to play around with so I'll post when I have some results.
Dan Diaconu December 27th, 2004, 03:46 PM yes, let us see some pics.
Brett Erskine December 29th, 2004, 02:38 PM Okay guys heres the low down on all of these diffusers your mentioning. Sadly I've been posting on this project since the very begining so I've heard all of these diffusers being tested for this purpose. (According to what was posted):
Holographic Diffusers are simply diffusers that have highly diffused characteristics. By doing so they create a image that is unlikely to create a hotspot because light is diffused at a much wider and even angle than traditional ground glass. This is good when it comes to getting rid of the hot spot BUT this also creates a problem. Since the light is going in all directions only a small portion of it is actually directed towards the CCDs. This means the image is much darker than traditional GG. Not good. Now they come in different versions with some less diffused than others but it was determined even the brightest wasnt nearly as bright as GG.
Beattie screens are regarded by most photographers as the brightest screens. I've tested them and they are indeed bright but there is another much smaller company out there that makes screens that people swear by. The company is called Maxwell Precision Optics. Thoughs that have owned both Maxwell and the Beattie insist that the Maxwell screens are even brighter. I've tried them both out but never side by side. I own a Maxwell and I'm happy with it. The reason the Maxwell may perform better is the fact that the fresnel lens is both finer and can be ordered to match a given focal length. In other words you can get one that can be perfectly calibrated to your system. No hot spot, bright and fine fresnel lens. However the company is so small they dont even have a website. I did a search for it to find the address and phone number. The owner is a Bill Maxwell and a incredibly knowledgeable guy when it comes to optics. Thoughs thinking about using it for a static adapter might want to keep looking though because while the grain is small isnt not too small that you cant see it. And if you are making it oscillate it better be a very very small movement because you have to remember once you make the PCX lens (fresnel) and the GG one they are forced to move together thus their focal point moves as well. If it moves too far off center of the CCD you'll get a hot spot again.
If you are looking for a focusing screen that is as grainless as they get look at the laser etch screens in the new pro model Canon EOS bodies. They are incredible BUT (dont you hate that?) they dont make them without markings. Find a way to get it without markings and I'd think you'd be in business.
Brett Erskine
Dan Diaconu December 29th, 2004, 03:31 PM Brett,
Thanks for passing this one by.
I did not know of Maxwell (I knew there were others) but did
not bother to look them all up front. One of the best is good enough for a "proof of concept".
(from what I know, Beattie also can do custom focal lenght on the Fresnel, but that is a lot of money)
About contrast.
When I first ordered from them, I specifically requested a bright but low contrast screen (or if they can make one) Tough luck.
Reason: a lower contrast would act as a better "translator" between real life contrast ratio (sometimes as high as 14 stops) and the CCD's limited range. (less than film anyway) I hope this helps.
That awfull hi-contrast (aside from huge DOF) makes video look as it does.
Just a thought for the non moving concept. If the image form
the grainless GG is good enough on a 50" plasma (and it doesn't show any patern) than that might be the solution.
(although some might be tempted to print on film (for theatre) from HD )
Well.....looks like we can't have it all.
Aaron Shaw December 29th, 2004, 04:09 PM Brett,
How sure are you about the holographic diffusers? I see no reason that they should exhibit the characteristics you have given them.
You can define how spread out the light becomes from several degrees into much larger numbers. These are used in TVs and monitors all the time precisely for their ability to show a great image. Who tested the holographic diffuser in the past?
Richard Mellor December 29th, 2004, 04:44 PM somewhere in times past someone tested the holographic diffusers. I just can not find it
Aaron Shaw December 29th, 2004, 04:52 PM Neither can I. I know these things are used in projection displays as well so they _can_ work... somehow.
I suspect the person tested the material using a LSD that had a high angular divergence (60+ degrees).
Just a guess though. I may be entirely wrong!
Aaron Shaw December 30th, 2004, 12:44 AM Just sent off an email to POC detailing our specific needs and asking for guidance. I'll let you guys know if/when I hear back from them and whether they think their materials can be benefitial to us.
Brett Erskine December 30th, 2004, 01:40 PM Once again I wasnt the one who tested the holographic diffusers so I cant tell you first hand. I only recal what others have said about them. I wish I could point you to all the post when it was a hot topic but I dont know where they are. You'll notice though that they didnt say it wouldnt work. In fact they did but it would be much too dark. I know it has a cool name ("holographic") but they arent doing anything magical. Just think about what light is doing when it hits a diffused surface and how much it would have to be diffused in order for it to appear equally bright from different angles. Very diffused. Its a physical impossibilty for a diffuser to be viewable from multiple angles AND be bright. This is why they are using less diffused GG and field lenses and/or fresnel lenses in cameras to focus the light where it needs to go.
Dan Diaconu December 30th, 2004, 02:14 PM >>>>>>Hi Dan,
Thank you for your interest in POC. Depending on your source divergence, it is possible that a diffuser will work without the Fresnel lens. If you have a large source divergence, you can laminate a POC diffuser to a Fresnel lens. The Fresnel lens reduces reflection and scattering losses.
Best regards and happy new year,
Jeff Laine
POC>>>>>>>>>>
Aaron Shaw December 30th, 2004, 08:49 PM Brett,
I see what you mean. However, how diffuse you get can be precisely specified in the manufacturing process. Anywhere from percents of a degree to full blown 180.
What effect this would have upon the ability to remove hotspots I don't know. In any case I think the real benefit that these *may* provide is a very high transmission efficiency - especially with the ability to precisely control where that light is going (even if you end up with a hotspot).
Brett Erskine January 1st, 2005, 06:05 PM Aaron-
You just answered your own question. The angle rating of the diffuser IS how you can tell how effective the diffuser will be at removing the hot spot.
As far as their transmission efficency I would recomend going by what others that have tested them for this project had to say. They said they were too dark.
Aaron Shaw January 1st, 2005, 06:08 PM Yeah I seem to be good at doing that sort of thing :D. Ah well...
I'm still going to find one to play around with though. Just in case I can get decent results. It's too bad that there have been negative comments about them. They could have been a very good solution!
On a side note: does anyone know where to find lenses large enough to work with MF? I'm having trouble finding this sort of thing for my project.
EDIT: Lenses as in condensers, cylindricals etc not actual MF lenses.
Brett Erskine January 1st, 2005, 06:20 PM Edmunds Scientific, Surplus Shed or Anchor Optics. Google it for the web sites.
Aaron Shaw January 1st, 2005, 06:34 PM Thanks Brett. I have looked at Edmund Optics, the Surplus Shed, and Opto Sigma but the largest I can usually find is 50mm in diameter. I would like to get 60mm at least. For instance, Opto-Sigma only makes a 50mm GG. :(
Steven Fokkinga January 11th, 2005, 03:48 PM Hi Dan,
Are you progressing on the adapter? When do you expect to have a testable prototype? Also do you have in the meantime some high(er) quality footage??
Keep the good work up!
Steven
Dan Diaconu January 11th, 2005, 04:25 PM Thanks Steven,
I have to wear a few hats (at the same time) in this process, which made me bang the walls, but it's refreshing.........whoa!
I allready have tested the prototypes I made, but I have improved the design. I can drop it on concrete now, pick it up and shoot (if the lens is still there....lol)
Not that I recomend it!!!!
I have seen too many times what an "early release" can do to a lot of work. I can not AFFORD THAT.
I will keep my promise to deliver what I promised.
Daniel Stone January 17th, 2005, 12:54 AM Anyone ever used a BosScreen? I hear it's a completely grain-free ground glass with excellent picture contrast. If this is so, it may be an excellent choice for a non-oscilating ground glass unit.
I'm thinking about ordering a sheet just for test-purposes unless someone on here has used it before.
Here's the link:
http://www.stabitech.nl/Bosscreen.htm#top
Régine Weinberg January 17th, 2005, 12:59 AM G'day, I do know that link and the only con ---it melts if it is hot
and or direct sunlight --after the sreen is gone to be useless.
Daniel Stone January 17th, 2005, 01:15 AM Yea, I saw that - kinda sucks ... but if it's really as good as I've read, it'd be totally worth it to me to treat it with 'special' care.
I've sent them an email to get pricing on a smaller sheet without grid lines. We'll see.
Frank Ladner January 17th, 2005, 09:36 AM I've been experimenting with microcrystalline wax and it is definately better (in terms of grain (( none visible )) and sharpness) than any ground glass I've tested. I think it is the best static solution. I've yet to have any wax melt, but I have taken a hairdryer and intentionally melted the wax that was sealed between glass (couldn't escape) to see the effects. After it cooled it was right back to normal. I'm not sure if there would be any discoloration due to reheating over the long term, but I don't think it would be a big problem.
Given the quality of Microcrystalline wax (if you get the right thickness w/o bubbles), I think it would be easier to go through the trouble of building some kind of small cooling system than to build rotating / oscillating glass solutions. (Taking into consideration the precision required with the non-static adapters.)
Jim Lafferty January 17th, 2005, 09:38 AM There's no reason to expect a Boss Screen or any other microwax screen to "melt" provided you keep your camera away from blisteringly hot circumstances -- which you do normally, right? An example of how you could melt such a screen would be to leave your camera and adapter in the trunk of your car on an exceptionally hot day for hours at a time.
Dan Diaconu January 17th, 2005, 10:38 AM Frank,
Would it possible for us to see a 4 sec clip showing something sharp ECU (about 1/3 of the frame) while barely panning? It would be nice to see how clean the BG looks like when soft. Or even easier: 1.4 (or otherwise wide open ) 50-85-135mm lens, night shot, city lights, focus at the closest setting of the lens. Sloooow pan. It should look nice.
Frank Ladner January 17th, 2005, 11:17 AM Dan: I will definately try and capture some closeup, barely-panning footage. I won't be able to do the "city lights" thing for ya, though as I live out in the woods. LOL!
Here's some of the footage / framegrabs I have available now, in case you haven't seen them:
http://209.214.235.122/mwtest/
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