Your current configuration? at DVinfo.net

Andrew Clunie · April 23rd, 2007, 04:28 PM

Hey guys. I am fairly new to this stuff, so my knowledge is pretty limited, but i have learn't pretty much all i know from this site so thank you all!

Right, i have started putting together my adapter and i am wondering how you have yours set up. What i have come to understand, this seems the ideal one for me:

Lens.....GG...condenser....macro...camera

I was just interested to see how you guys have yours set up cause i have come across so many different ways. Also i have a question. Does a Macro do the same thing as an achromatic lens? And is a pcx lens similar to a condenser lens? Do they both reduce vignetting or am i way off?

Thanks, Andrew

Mike Dulay · April 23rd, 2007, 06:40 PM

Andrew,

I'm currently using a static, working on a vibrating and a spinner. My static setup is:

Nikon Lens - F-mount - Nikon F3 Type D (Condenser and GG) - 58mm +10 Singlet Macro - camera

see the story at http://yousillyman.blogspot.com

When people say macro they often mean the singlet macro (diopeter) which does the same thing BUT does not correct for chromatic aberration. It's primary function is to allow your camera to focus on the focus screen. An achromatic diopeter has two lenses instead of one. This corrects the chromatic aberration and is visually better. An apochromatic diopeter has three lenses ....

PCX = plano convex lens, which refers to the condenser's shape. This is flat on one side and a shallow rounded curve on the other. The condenser is there to reduce vignetting as you mention.

Most beginners start with either a static or a spinner. Which one you go with depends on how easily you can get a ground glass.

Bob Hart · April 23rd, 2007, 09:36 PM

Vignetting versus edge/corner brightness fall-off, also sometimes known as hotspot.

Vignetting is the edges of the optic itself cutting off the corners off the image by being too small in diameter. The cut off areas are dark, the effect something like looking down a pipe if the vignetting is extreme.

Edge/corner brightness fall-off is the gradual darkening towards the corners or edges but image is otherwise there across the whole frame. The darker areas are caused by inability of the optics to deliver even light value across the whole frame.

To complicate things, a vignette and edge/corner brightness fall-off might be caused by the optic being too small in diameter.

The edge/corner brightness fall-off will be seen first, then the vignette itself appears if the guilty optical element is moved forward.

A condenser or PCX lens or pair can help with edge/corner bightness fall-off.

These are my understandings of the definitions. Maybe somebody should correct me if I am wrong.

Chris Barcellos · April 23rd, 2007, 10:04 PM

Hey Andrew:

I built a spinner, using plans from Redrockmicro people and there disk as my guide. I used a 72mm achromat from Cinevate at about $250.00. I had no condensor, but I did have about a 5 inch spacer from the achromat to the ground glass. This gave me good focus on good image and room to zoom in and out. I am able to focus my FX1 to fill the screen with a Pentax normal lens.

Here is what the contraption looked like. It actually turned out pretty solid.

http://www.dvinfo.net/conf/attachmen...7&d=1164515894

See this thread for more discussion.

http://www.dvinfo.net/conf/showthread.php?t=80383

I now have a Letus35a, and it uses an achromat as well as a condenser. It does not give a huge zoom range, but he image appears to be better.

Andrew Clunie · April 24th, 2007, 04:34 AM

Thanks for the informative replies.

I made a real quick crude model, just to pretty much see the projection on gg. My gg is very poor at the mo (a shoddy sanded cd) so there is major hotspot and vignetting. I have another cd which i will sand with finer sand paper and put a lot more time into it, so i was wondering, to get rid off the vignetting and hot spot, i need a condenser, but should i put it between the gg and lens, or gg and camera.

lens...condenser...gg...macro..cam or

lens...gg...condenser...macro...cam

also, does it matter how far or close the condenser is to the gg?

Tell me the way you have yours set up, ie in what order things are.

edit: Also is the redrock guide worth getting? It seems useful, especially for the gg thats included. Is the GG in the form of the cd? sorry for all the questions :)

Thanks, Andrew

April 23rd, 2007, 04:28 PM	#1
Andrew Clunie New Boot Join Date: Mar 2007 Location: London, England Posts: 12	Your current configuration? Hey guys. I am fairly new to this stuff, so my knowledge is pretty limited, but i have learn't pretty much all i know from this site so thank you all! Right, i have started putting together my adapter and i am wondering how you have yours set up. What i have come to understand, this seems the ideal one for me: Lens.....GG...condenser....macro...camera I was just interested to see how you guys have yours set up cause i have come across so many different ways. Also i have a question. Does a Macro do the same thing as an achromatic lens? And is a pcx lens similar to a condenser lens? Do they both reduce vignetting or am i way off? Thanks, Andrew

April 23rd, 2007, 06:40 PM	#2
Mike Dulay Major Player Join Date: Mar 2007 Location: Somerville, NJ Posts: 304	Andrew, I'm currently using a static, working on a vibrating and a spinner. My static setup is: Nikon Lens - F-mount - Nikon F3 Type D (Condenser and GG) - 58mm +10 Singlet Macro - camera see the story at http://yousillyman.blogspot.com When people say macro they often mean the singlet macro (diopeter) which does the same thing BUT does not correct for chromatic aberration. It's primary function is to allow your camera to focus on the focus screen. An achromatic diopeter has two lenses instead of one. This corrects the chromatic aberration and is visually better. An apochromatic diopeter has three lenses .... PCX = plano convex lens, which refers to the condenser's shape. This is flat on one side and a shallow rounded curve on the other. The condenser is there to reduce vignetting as you mention. Most beginners start with either a static or a spinner. Which one you go with depends on how easily you can get a ground glass. __________________ DIY, 35mm, HV20: http://www.primitivebuteffective.net

April 23rd, 2007, 09:36 PM	#3
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Vignetting versus edge/corner brightness fall-off, also sometimes known as hotspot. Vignetting is the edges of the optic itself cutting off the corners off the image by being too small in diameter. The cut off areas are dark, the effect something like looking down a pipe if the vignetting is extreme. Edge/corner brightness fall-off is the gradual darkening towards the corners or edges but image is otherwise there across the whole frame. The darker areas are caused by inability of the optics to deliver even light value across the whole frame. To complicate things, a vignette and edge/corner brightness fall-off might be caused by the optic being too small in diameter. The edge/corner brightness fall-off will be seen first, then the vignette itself appears if the guilty optical element is moved forward. A condenser or PCX lens or pair can help with edge/corner bightness fall-off. These are my understandings of the definitions. Maybe somebody should correct me if I am wrong. Last edited by Bob Hart; April 23rd, 2007 at 09:43 PM. Reason: post-posting distillation of fact and possible disinformation. I do not know it all.

April 23rd, 2007, 10:04 PM	#4
Chris Barcellos Inner Circle Join Date: Nov 2005 Location: Elk Grove CA Posts: 6,838	Hey Andrew: I built a spinner, using plans from Redrockmicro people and there disk as my guide. I used a 72mm achromat from Cinevate at about $250.00. I had no condensor, but I did have about a 5 inch spacer from the achromat to the ground glass. This gave me good focus on good image and room to zoom in and out. I am able to focus my FX1 to fill the screen with a Pentax normal lens. Here is what the contraption looked like. It actually turned out pretty solid. http://www.dvinfo.net/conf/attachmen...7&d=1164515894 See this thread for more discussion. http://www.dvinfo.net/conf/showthread.php?t=80383 I now have a Letus35a, and it uses an achromat as well as a condenser. It does not give a huge zoom range, but he image appears to be better. __________________ Chris J. Barcellos

April 24th, 2007, 04:34 AM	#5
Andrew Clunie New Boot Join Date: Mar 2007 Location: London, England Posts: 12	Thanks for the informative replies. I made a real quick crude model, just to pretty much see the projection on gg. My gg is very poor at the mo (a shoddy sanded cd) so there is major hotspot and vignetting. I have another cd which i will sand with finer sand paper and put a lot more time into it, so i was wondering, to get rid off the vignetting and hot spot, i need a condenser, but should i put it between the gg and lens, or gg and camera. lens...condenser...gg...macro..cam or lens...gg...condenser...macro...cam also, does it matter how far or close the condenser is to the gg? Tell me the way you have yours set up, ie in what order things are. edit: Also is the redrock guide worth getting? It seems useful, especially for the gg thats included. Is the GG in the form of the cd? sorry for all the questions :) Thanks, Andrew