Octagon35: spinner w/flipper, relay and bellows

Cole McDonald · July 26th, 2006, 09:09 AM

I've looked around and can't seem to find any alternatives to this program tha will run under OSX (Mac or X11 based). I'd like to get my adaptor going as I've completed building my rail system and the adapter...just have to get the inbetweeny bits working.

Justine Haupt · July 27th, 2006, 09:24 AM

I'm stricktly a Windows user, so I don't have any suggestions... but by no means do you need such a program. I just pointed to it in case someone anyone wanted to give it a try.

Justine Haupt · August 2nd, 2006, 09:35 PM

Well, it's not quite finished yet, but I just couldn't resist posting some preliminary screenshots. (I'll start a new posting when the "real" screen shots are up).

I'm still experimenting with different condensors and like I said they are preliminary shots... still tweaking, calibrating, etc. The GG (Thor Labs 1500 grit) is a vast improvement over the other one I was using, but it's a little bit too transparent... in some of the footage I have the highlights tend to glow (notice the paper on the third shot). The first two shots look great on one computer, and marginal on the other... they were shot late today with just a little available light.

http://www.particleproducing.com/images/o35-2c.jpg
http://www.particleproducing.com/images/o35-3c.jpg
http://www.particleproducing.com/images/o35-5.jpg

EDIT 8/3: Just shot these and thought I'd add 'em:
http://www.particleproducing.com/images/o35-7.jpg
http://www.particleproducing.com/images/o35-8.jpg

I have some new condensors on order, and the mounting bracket's already in place, so it's almost ready to shoot with. I think it's just a matter of evening out the lighting some more.

EDIT 8/3: I just ordered a Satin Snow GG... after experimenting with different glasses, I feel like the Satin Snow will be just what I'm after.

Complaints with the Thor Labs glass:

-Highlights "glow"
-Vignetting is intense and difficult to correct
-Bokeh sucks. I know this is normally a quality of the lens, but I definately realize that it matters what the lens is projecting onto. (See the fourth pic as an example).

Dennis Wood · August 3rd, 2006, 02:01 PM

Justin, I just checked out your thread here...very nice work! You have a world of experimentation ahead of you on the GG side :-) I've yet to see a spinning design (including M2) that did not show halation on specular highlights (particulary during focus pulls) so you may just have to live with it. I believe it is an interaction between the GG's clear side and the diffusor surface.

Justine Haupt · August 3rd, 2006, 11:32 PM

Quote:

Originally Posted by Dennis Wood

I've yet to see a spinning design (including M2) that did not show halation on specular highlights (particulary during focus pulls) so you may just have to live with it. I believe it is an interaction between the GG's clear side and the diffusor surface.

Hmm, that's not what I wanted to hear! But I do think adapters like the M2 at least have less halation, no? The vignetting I can fix... the fuzziness I can work on... but the only way I know to improve the glowing is with another GG. Do you think I'm on a wild goose chase, or is it possible to get it any better?

Obviously I'll have much more control over the highlights during an actual production (lighting), but it's still an issue.

Please, any advice would be appreciated! Anyone! Anyone?

Bob Hart · August 3rd, 2006, 11:59 PM

An anti-reflective coating on the front surface as long as the shiny side is to the front would help. It is a long established method with lens optics, however it is also high science beyond my resources.

I am using optical glass disks.

I had limited but highly unpredictable results with imperfect polishing of the front surface which left a fairly dense scatter of smooth microscopic pits in the polished surface. It does not seem to affect the resolution but seems to affect light transmission.

The contrast seems to be better than with a disk with a totally smooth front surface. However my efforts at a home made level between individual finishing stages of disks and final groundglass textures are probably too variant and combined for this to be a valid suggestion.

The pitted polish also seems to aggravate flicker effect as I was unable to achieve a consistent density of pits around the entire disk because some areas would polish out entirely.

Optical coatings as for lenses would be the only way to go as I see it.

Justine Haupt · August 4th, 2006, 08:06 AM

Oh wait... you have your shiny side in the front? I have the ground side facing the front (I thought that was standard practice to reduce light loss from reflections off the front). Is there an advantage to having the ground side face the camera? On one hand it makes sense to me to have the ground surface/image plane facing the relay lens, but I assumed that it didn't matter because everyone (I thought) faces it forward to eliminate front reflections.

In any case, I give you credit for trying to apply any kind of process to the glass... and if I understand right, you're grinding them yourself, too?

Bob Hart · August 4th, 2006, 09:59 AM

Shiny side to the front is the way I have done it and I think many builders have gone that way. I don't know what the theoretical advantage is.

An overbrightness point on a groundglass rear face will spread forward then some will reflect back as a spill around the bright point. Hopefully most goes out through the shiny side.

An overbrightness point on a front groundglass face will spread rearward. Some will be reflected forward as a spill projection around the bright point.

I don't know if there is any particular advantage.

I think any advantage would rest in that any reflection from defects, dust, fingerprints, etc., on the shiny surface in front of the groundglass will go forward and disappear into the non-reflective black internal finish of the adaptor and may be seen only as a shadow by the camera.

Whereas if the groundglass surface is on front, some defects or dust stuck to the shiny side might reflect light back onto the groundglass surface and then become surrounded by a small coronal light spill visible enough to spoil contrast.

This is purely theoretical gibberish on my part and not backed up by any research whatever, so don't take too much notice.

Forrest Schultz · August 5th, 2006, 06:26 PM

"This is purely theoretical gibberish on my part and not backed up by any research whatever, so don't take too much notice."

Bob Hart, the most helpful man in the world, and still the most modest also.

July 26th, 2006, 09:09 AM	#16
Cole McDonald Trustee Join Date: Nov 2005 Location: Sauk Rapids, MN, USA Posts: 1,675	I've looked around and can't seem to find any alternatives to this program tha will run under OSX (Mac or X11 based). I'd like to get my adaptor going as I've completed building my rail system and the adapter...just have to get the inbetweeny bits working. __________________ Web Youtube Facebook

July 27th, 2006, 09:24 AM	#17
Justine Haupt Major Player Join Date: Oct 2005 Location: Long Island, NY Posts: 208	I'm stricktly a Windows user, so I don't have any suggestions... but by no means do you need such a program. I just pointed to it in case someone anyone wanted to give it a try. __________________ ~Justine "We are the music makers, and we are the dreamers of dreams" -Arthur O'Shaunessey (as quoted by Willy Wonka)

August 2nd, 2006, 09:35 PM	#18
Justine Haupt Major Player Join Date: Oct 2005 Location: Long Island, NY Posts: 208	First screens. Well, it's not quite finished yet, but I just couldn't resist posting some preliminary screenshots. (I'll start a new posting when the "real" screen shots are up). I'm still experimenting with different condensors and like I said they are preliminary shots... still tweaking, calibrating, etc. The GG (Thor Labs 1500 grit) is a vast improvement over the other one I was using, but it's a little bit too transparent... in some of the footage I have the highlights tend to glow (notice the paper on the third shot). The first two shots look great on one computer, and marginal on the other... they were shot late today with just a little available light. http://www.particleproducing.com/images/o35-2c.jpg http://www.particleproducing.com/images/o35-3c.jpg http://www.particleproducing.com/images/o35-5.jpg EDIT 8/3: Just shot these and thought I'd add 'em: http://www.particleproducing.com/images/o35-7.jpg http://www.particleproducing.com/images/o35-8.jpg I have some new condensors on order, and the mounting bracket's already in place, so it's almost ready to shoot with. I think it's just a matter of evening out the lighting some more. EDIT 8/3: I just ordered a Satin Snow GG... after experimenting with different glasses, I feel like the Satin Snow will be just what I'm after. Complaints with the Thor Labs glass: -Highlights "glow" -Vignetting is intense and difficult to correct -Bokeh sucks. I know this is normally a quality of the lens, but I definately realize that it matters what the lens is projecting onto. (See the fourth pic as an example). __________________ ~Justine "We are the music makers, and we are the dreamers of dreams" -Arthur O'Shaunessey (as quoted by Willy Wonka) Last edited by Justine Haupt; August 3rd, 2006 at 09:03 AM.

August 4th, 2006, 08:06 AM	#22
Justine Haupt Major Player Join Date: Oct 2005 Location: Long Island, NY Posts: 208	Oh wait... you have your shiny side in the front? I have the ground side facing the front (I thought that was standard practice to reduce light loss from reflections off the front). Is there an advantage to having the ground side face the camera? On one hand it makes sense to me to have the ground surface/image plane facing the relay lens, but I assumed that it didn't matter because everyone (I thought) faces it forward to eliminate front reflections. In any case, I give you credit for trying to apply any kind of process to the glass... and if I understand right, you're grinding them yourself, too? __________________ ~Justine "We are the music makers, and we are the dreamers of dreams" -Arthur O'Shaunessey (as quoted by Willy Wonka)

August 3rd, 2006, 02:01 PM	#19
Dennis Wood Major Player Join Date: Mar 2005 Location: Ontario, Canada Posts: 916	Justin, I just checked out your thread here...very nice work! You have a world of experimentation ahead of you on the GG side :-) I've yet to see a spinning design (including M2) that did not show halation on specular highlights (particulary during focus pulls) so you may just have to live with it. I believe it is an interaction between the GG's clear side and the diffusor surface.

August 3rd, 2006, 11:59 PM	#21
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	An anti-reflective coating on the front surface as long as the shiny side is to the front would help. It is a long established method with lens optics, however it is also high science beyond my resources. I am using optical glass disks. I had limited but highly unpredictable results with imperfect polishing of the front surface which left a fairly dense scatter of smooth microscopic pits in the polished surface. It does not seem to affect the resolution but seems to affect light transmission. The contrast seems to be better than with a disk with a totally smooth front surface. However my efforts at a home made level between individual finishing stages of disks and final groundglass textures are probably too variant and combined for this to be a valid suggestion. The pitted polish also seems to aggravate flicker effect as I was unable to achieve a consistent density of pits around the entire disk because some areas would polish out entirely. Optical coatings as for lenses would be the only way to go as I see it.

August 4th, 2006, 09:59 AM	#23
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Shiny side to the front is the way I have done it and I think many builders have gone that way. I don't know what the theoretical advantage is. An overbrightness point on a groundglass rear face will spread forward then some will reflect back as a spill around the bright point. Hopefully most goes out through the shiny side. An overbrightness point on a front groundglass face will spread rearward. Some will be reflected forward as a spill projection around the bright point. I don't know if there is any particular advantage. I think any advantage would rest in that any reflection from defects, dust, fingerprints, etc., on the shiny surface in front of the groundglass will go forward and disappear into the non-reflective black internal finish of the adaptor and may be seen only as a shadow by the camera. Whereas if the groundglass surface is on front, some defects or dust stuck to the shiny side might reflect light back onto the groundglass surface and then become surrounded by a small coronal light spill visible enough to spoil contrast. This is purely theoretical gibberish on my part and not backed up by any research whatever, so don't take too much notice.

August 5th, 2006, 06:26 PM	#24
Forrest Schultz Major Player Join Date: Mar 2005 Location: Atwater, CA Posts: 246	"This is purely theoretical gibberish on my part and not backed up by any research whatever, so don't take too much notice." Bob Hart, the most helpful man in the world, and still the most modest also.