Microcrystalline Wax Techniques? - Page 40 at DVinfo.net
DV Info Net

Go Back   DV Info Net > Special Interest Areas > Alternative Imaging Methods

Alternative Imaging Methods
DV Info Net is the birthplace of all 35mm adapters.

Reply
 
Thread Tools Search this Thread
Old November 21st, 2005, 10:27 PM   #586
Major Player
 
Join Date: Jul 2004
Posts: 587
Ooh intersting question. I'm not entirely certain what effect an aspheric element would have on bokeh if any. Hmm, I'll have to ponder that. As far as I know there shouldn't be any effect in the out of focus areas that you don't see in the sharp areas. The only thing I can think of off the top of my head which might cause a difference is the angle at which the light from the 35mm lens hits the aspheric element (as it isn't colliminated when emerging from the 35mm lens). 35mm lenses use these often enough though that I doubt it would make any overly noticable difference. The fact that everyone shoots wide open all the time might have something to do with it since anything out of focus becomes much more obvious.

As for the lens you posted... "condenser" lenses are designed to be very fast so the thickness isn't a problem in that case. The problem is that with speed comes aberration. Unless you stay at the precise focal length of that element I suspect your image quality will go to crap (heck it might even do so anyway). The hard part is balancing speed with quality (in any system really). To get really fast optics that are clean you really have to go with custom designed and ground elements. Of course, the amount of aberration people see as acceptable differs from person to person.

Geeze it' been a while since I posted here! Always good to come back now and then. =D
Aaron Shaw is offline   Reply With Quote
Old November 22nd, 2005, 04:20 AM   #587
Major Player
 
Join Date: Jan 2005
Location: (The Netherlands - Belgium)
Posts: 735
Thanks Aaron.
Maybe you know why the condenser lenses I use work so good. I took two lenses from from old optics. One front piece of a 135mm telephoto lens. One front (or second) piece of glass from a super8 zoomlens. They are both just big enough to use in front and behind the wax GG (like a sandwich). They are relatively thin.
I seems they strongly reduce each others aberrations.
Oscar Spierenburg is offline   Reply With Quote
Old November 22nd, 2005, 09:05 AM   #588
Regular Crew
 
Join Date: Aug 2005
Location: Belgium
Posts: 94
About the circular blurred parts, Wayne pointed me to an interesting website where some explanation can be found:

http://www.vanwalree.com/optics/bokeh.html

Read: 'Shape of the blur patch'

Thanks, Wayne
Kurt August is offline   Reply With Quote
Old November 22nd, 2005, 09:16 AM   #589
Major Player
 
Join Date: Jun 2005
Location: Brighton, East Sussex, UK
Posts: 938
Actually, we need to credit Dan Diaconu for providing that useful link.
__________________
Thanks,
Wayne.
Wayne Kinney is offline   Reply With Quote
Old November 22nd, 2005, 02:49 PM   #590
Major Player
 
Join Date: Mar 2005
Location: Ventura, California, USA
Posts: 751
Quote:
Originally Posted by Aaron Shaw
Bill, I'm sure you've dealt with this before to some degree at least? As far as I know there shouldn't be any effect in the out of focus areas that you don't see in the sharp areas.
'Bokeh' only refers to out-of-focus areas. And typically, sharp areas don't show the same effects as in the out of focus areas, unless there is something really wrong with the optics of that make/model lens.

Theoretically, I think a lens' bokeh traits probably are present in the sharp areas, but let's think about the reason they're not visible: What is bokeh? It's a pinprick of light, a highlight, "blown up" to much larger size. In sharp areas, the pinpricks are still almost infinitessimally small.
Bill Porter is offline   Reply With Quote
Old November 22nd, 2005, 05:28 PM   #591
Major Player
 
Join Date: Jan 2005
Location: (The Netherlands - Belgium)
Posts: 735
Yes, but Kurt seems to be right about the bokeh looking differently on these wax adapters. One of the reasons that I think the G35 has something waxy going on.
Unless it has something to do with the fact that wax can be made very thin, so you have the highlights reflecting on the condensers as well (just my theory though) . It could be that the G35 isn't a wax adapter, but uses a different diffusing material with the same thickness of the wax layer. I don't know.
Oscar Spierenburg is offline   Reply With Quote
Old November 22nd, 2005, 06:48 PM   #592
Major Player
 
Join Date: Dec 2004
Location: Vancouver, Canada
Posts: 804
Quote:
Originally Posted by Bill Porter
It's a pinprick of light, a highlight, "blown up" to much larger size. In sharp areas, the pinpricks are still almost infinitessimally small.
That's right, and they go by the name of... circle of confusion (cough, cough) make that diffusion!
Dan Diaconu is offline   Reply With Quote
Old November 23rd, 2005, 02:39 AM   #593
Major Player
 
Join Date: Mar 2005
Location: Ventura, California, USA
Posts: 751
Ahhh, I misread or missed something in Kurt's post, perhaps. I didn't see the bit about bokeh looking different due to just the wax adapter. Interesting point. Oscar, if you or anyone has both a wax and a non-wax screen (such as ground glass), somebody ought to compare with the same lens!

Dan,

Now that was a bad one. LOL
Bill Porter is offline   Reply With Quote
Old December 4th, 2005, 06:25 PM   #594
Major Player
 
Join Date: Jan 2005
Location: (The Netherlands - Belgium)
Posts: 735
GuerillaMc35

Hey.. I just had a look at the new website of the Cinemek/guerilla35, but the first footage I played, montereyweb.mov, clearly shows a small amount of static grain on the shots were there is a lot of sunlight. All static adapters have the same thing when you close the iris, but we were told that the G35 was grainless. (I'm not talking about the large amount of compression artifacts)
So, whether it is a wax adapter or not, I can surely see (now) that it has the same characteristics. Anyway, it's not better than microwax....meaning that wax is the end of the static quest?

(there is some very good footage their site by the way, they should post some frame grabs)
Oscar Spierenburg is offline   Reply With Quote
Old December 4th, 2005, 07:28 PM   #595
Major Player
 
Join Date: Mar 2005
Location: Ventura, California, USA
Posts: 751
I love that clip. According to SavvyPro's site it was a demo G35 unit from half a year ago. I know a lot has changed since then. Maybe Jonathan will chip in about how much different it is from current production units.

But, I don't know who from Cinemek said the G35 was grainless... ? I did see a post some months back where Jonathan said it wasn't totally grainless. But it sure is the nicest of any of the adapters I've seen.

I guess it is a subjective term too, because even film has grain, though not due to any adapter of course. The only thing without grain is... pure video?
Bill Porter is offline   Reply With Quote
Old December 4th, 2005, 10:43 PM   #596
Major Player
 
Join Date: Apr 2005
Posts: 285
Moving grain is inherent to the random nature of light. Even your eyes have it. Everything does.

Static grain, of course, is due to the size of the pores in the diffusion screen.
Matthew Wauhkonen is offline   Reply With Quote
Old December 5th, 2005, 05:02 AM   #597
Trustee
 
Join Date: Jun 2005
Location: Hollywood, CA
Posts: 1,675
Images: 1
I'm still clueless about how the Cinemek adapter could possibly be grainless in all situations if it's static. Someone mentioned using Sapphire around here as a focusing screen...

Anyways, all the details will apparently be released within the next few weeks, but from what I understand that phrase is wayyy overused over there.
__________________
BenWinter.com
Ben Winter is offline   Reply With Quote
Old December 5th, 2005, 07:16 AM   #598
Major Player
 
Join Date: Jan 2005
Location: (The Netherlands - Belgium)
Posts: 735
<<But, I don't know who from Cinemek said the G35 was grainless... ?>>

Call it 'virtually grainless' or something, but this clip shows virtually grainy shots and some vignetting.

My point was, it's very good, but it seems to be the same quality as microwax. In the best possible conditions (cloudy sky?) the microwax is virtually grainless. Too much light would make you close down the iris and some grain will appear.
Oscar Spierenburg is offline   Reply With Quote
Old December 5th, 2005, 07:27 AM   #599
Trustee
 
Join Date: Jun 2005
Location: Hollywood, CA
Posts: 1,675
Images: 1
Quote:
Too much light would make you close down the iris and some grain will appear.
The common understanding to avoiding grain is that you leave the SLR iris open fully and use an ND filter or close the iris in the camera itself if there's too much light.
__________________
BenWinter.com
Ben Winter is offline   Reply With Quote
Old December 5th, 2005, 09:08 AM   #600
Major Player
 
Join Date: Apr 2005
Posts: 285
Jonathan quoted no grain at f2.8, usable at f4 and at some cases f5.6, beyond that there are grain issues a while back...

Then HD got big, and grain become much more of a concern so apparently there are improvements.

It will be interesting to see....
Matthew Wauhkonen is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Special Interest Areas > Alternative Imaging Methods

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



All times are GMT -6. The time now is 12:23 AM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network