Whats the Best Ground Glass? at DVinfo.net

Orestes Mita · October 25th, 2005, 04:27 PM

I've seen different types of ground glass used on 35mm adapters and they all create some grain - anyone know which one you can get the best image with?

Wayne Kinney · October 25th, 2005, 04:59 PM

Are you intending for a static design? If so, i would recommend viewing the 'Microwax techniques' thread. You can also try a professional 1500 grit glass from optosigma or thorlabs. Either that or try grinding your own glass with 1500 grit aluminium oxide

Wayne

Steev Dinkins · October 25th, 2005, 05:26 PM

If you're going with a static design, the wax has been said to be the best, although the most elusive (has anyone really made these, and do they last?).

However, you can get great results from using a Beattie Intenscreen. That is what I'd recommend to anyone doing a static design at this point. They are easily available, although a little expensive, and probably the least amount of grain possible without going to a moving element design.

If you are making a device that will spin or vibrate the GG/focus screen, you may want to stick with an actual Ground Glass. I'd recommend the Thorlabs 1500 which comes in 2" round diameter, or the Opto Sigma which comes in a 50mm diameter (a little smaller). If you are mounting this in a filter ring, I can tell you which ones fit in which. I'd say the Opto Sigma is the least amount of grain of the two.

Good luck, and let me know if you're working on a moving element design. :)

Wayne Kinney · October 25th, 2005, 05:41 PM

The optosigma glass does have ghosting problems though. This is me trying the glass personally. I think Steev's Beattie Intenscreen option is best, or if thats too expensive, then grinding your own glass with Aluminium Oxide.

Wayne.

Jeff Phang · October 25th, 2005, 06:06 PM

I also say the beattie intenscreen is perhaps best and easiest option for static. On top of having almost no grain, it is incredibly easy to set up and doesn't require a condensor or anything. Here is a great example of a beattie screen. You can check my post down the page for another example of a beattie screen.

Oscar Spierenburg · October 26th, 2005, 05:29 AM

Steev, <<<has anyone really made these, and do they last?>>>
Frank Ladner made one. I made one and they last surprisingly good if you make them right. They stand the heat very well. Because I was so very cautious with it I dropped it allot of times on the floor. Nothing happened. It is as good as grainless.

Frank Ladner · October 26th, 2005, 10:18 AM

I hold to microwax being the best static solution available. However, Steev is right in calling it elusive because it is quite difficult to get right. Oscar's method seems to work well, though. If one has the patience to work with melted wax, the end result is very rewarding.

October 25th, 2005, 04:27 PM	#1
Orestes Mita New Boot Join Date: Oct 2005 Posts: 8	Whats the Best Ground Glass? I've seen different types of ground glass used on 35mm adapters and they all create some grain - anyone know which one you can get the best image with?

October 25th, 2005, 04:59 PM	#2
Wayne Kinney Major Player Join Date: Jun 2005 Location: Brighton, East Sussex, UK Posts: 938	Are you intending for a static design? If so, i would recommend viewing the 'Microwax techniques' thread. You can also try a professional 1500 grit glass from optosigma or thorlabs. Either that or try grinding your own glass with 1500 grit aluminium oxide Wayne Last edited by Wayne Kinney; October 25th, 2005 at 05:37 PM.

October 25th, 2005, 05:26 PM	#3
Steev Dinkins Major Player Join Date: Nov 2004 Location: San Francisco, CA Posts: 613	If you're going with a static design, the wax has been said to be the best, although the most elusive (has anyone really made these, and do they last?). However, you can get great results from using a Beattie Intenscreen. That is what I'd recommend to anyone doing a static design at this point. They are easily available, although a little expensive, and probably the least amount of grain possible without going to a moving element design. If you are making a device that will spin or vibrate the GG/focus screen, you may want to stick with an actual Ground Glass. I'd recommend the Thorlabs 1500 which comes in 2" round diameter, or the Opto Sigma which comes in a 50mm diameter (a little smaller). If you are mounting this in a filter ring, I can tell you which ones fit in which. I'd say the Opto Sigma is the least amount of grain of the two. Good luck, and let me know if you're working on a moving element design. :)

October 25th, 2005, 05:41 PM	#4
Wayne Kinney Major Player Join Date: Jun 2005 Location: Brighton, East Sussex, UK Posts: 938	The optosigma glass does have ghosting problems though. This is me trying the glass personally. I think Steev's Beattie Intenscreen option is best, or if thats too expensive, then grinding your own glass with Aluminium Oxide. Wayne.

October 25th, 2005, 06:06 PM	#5
Jeff Phang Regular Crew Join Date: May 2005 Location: Arlington, VA Posts: 34	I also say the beattie intenscreen is perhaps best and easiest option for static. On top of having almost no grain, it is incredibly easy to set up and doesn't require a condensor or anything. Here is a great example of a beattie screen. You can check my post down the page for another example of a beattie screen.

October 26th, 2005, 05:29 AM	#6
Oscar Spierenburg Major Player Join Date: Jan 2005 Location: (The Netherlands - Belgium) Posts: 735	Steev, <<<has anyone really made these, and do they last?>>> Frank Ladner made one. I made one and they last surprisingly good if you make them right. They stand the heat very well. Because I was so very cautious with it I dropped it allot of times on the floor. Nothing happened. It is as good as grainless.

October 26th, 2005, 10:18 AM	#7
Frank Ladner Major Player Join Date: Aug 2003 Location: Poplarville, MS Posts: 453	I hold to microwax being the best static solution available. However, Steev is right in calling it elusive because it is quite difficult to get right. Oscar's method seems to work well, though. If one has the patience to work with melted wax, the end result is very rewarding.