Ultimate: Broken Ground Glass at DVinfo.net

Mitchell Lewis · July 27th, 2009, 04:17 PM

EVERYONE: Be VERY careful when replacing the front housing on an Ultimate. I honestly don't know how or why it happened as I've removed/replaced the front cover many times before, but this time, when reassembling it, it caught the edge of the ground glass and snapped.

Guess how much a new GG for the Ultimate costs? Wait for it..................$499.

(any sympathy replies would be greatly appreciated)

BTW - The reason I was working on the unit was because I was having trouble with the GG not spinning up. I took it apart to see if the motor wire was incorrectly positioned (like the said on the Letus website). The wire was incorrectly positioned so I repositioned it and the motor seemed to spin up better. Also, in the process I found a fair number of specs on some of the other internal glass pieces, so I carefully cleaned them up (Nikon cleaning solution and cloth). They looked much better and I was looking forward to seeing if I had finally gotten rid of them. Oh well....you win some you loose some....

Bob Hart · July 27th, 2009, 10:53 PM

You have my sympathies entirely.

I made a bunch of groundglass disks for a home-made a few years back and broke about half of them, mostly in the manfacturing and two in service. They were fullsized CD disks but made of glass, which when dressed down was 0.9mm thick.

$499.00 seems hell expensive but this is an optical part which has to be made to precision in ten operations that I know of with a difficult raw material so there is no cheap way to do it in relatively small orders.

The drilling and centering of the spindle hole is a real mongrel as is the precise mounting of the disk.

In a sort of sheidenfreude way it is re-assuring at least to know that the Ultimate disk does break because we now know it is not plastic.

You are to be commended for sharing this info as other owners will know the care which needs to be taken.

In handling any of these devices for home repairs, I suggest owners buy a small tabletop vise or compact desktop carpenters workhorse vise to hold the body by flip enclosure so that you can use both hands on the front tube assembly when removing it and offering it back up to the body.

Mitchell Lewis · July 28th, 2009, 07:18 AM

Thanks Bob. One last point...

The clearance between the front cover/housing and the edges of the ground glass is very tight. So when you replace the front cover, just take your time and move slowly.

I don't want to scare any one. The Ultimate is a well made piece. I'm no expert on taking things apart. You just have to be a little careful and move slowly.

Mitchell Lewis · August 22nd, 2009, 08:41 AM

Just wanted to update everyone. They replacement Ground Glass showed up as Letus Direct had promised. I installed it and everything has been working fine ever since. While I had the unit apart, I thoroughly cleaned all the glass elements inside the unit, and now all the specs on my footage have disappeared!

The only problem I'm still having is getting the GG to spin up. Every once in a while, the GG won't spin up and I have to help it buy moving the camera rig in a circle (clients really look at me funny when I do this). I plan to send the unit back to Letus when my workload slows down. Hopefully they can replace the motor or something.

Bob Hart · August 23rd, 2009, 12:47 AM

Mitchell.

Did the spin-up issue pre-exist the glass breakage or occur after the new glass was installed?

I am only guessing here but you may need to switch on with speed set to highest and then adjust back to preferred operating speed.

Mitchell Lewis · August 29th, 2009, 10:18 AM

Thanks Bob. I've had this problem since the Ultimate was new. I've never used the Ultimate on anything but it's highest speed setting (never really understood why I would need/want to). My additional concern would be that the GG is actually spinning at it's correct speed. If the motor barely has enough strength to get the GG spinning, how do I know that it has enough strength to spin the GG at the correct speed.

I need to send the unit back to Letus in the next few months and have them swap out the motor.

Maybe I'm being a worry wart, but I'm a little concerned about the future of Letus. I don't know anything, but with all the new DSLR's coming out that can shoot video, there's going to be less and less of a need for a 35mm adaptor. (I hope I'm wrong and that both technologies can exist together)

July 27th, 2009, 04:17 PM	#1
Mitchell Lewis Trustee Join Date: Dec 2008 Location: Kennewick, WA Posts: 1,124	Ultimate: Broken Ground Glass EVERYONE: Be VERY careful when replacing the front housing on an Ultimate. I honestly don't know how or why it happened as I've removed/replaced the front cover many times before, but this time, when reassembling it, it caught the edge of the ground glass and snapped. Guess how much a new GG for the Ultimate costs? Wait for it..................$499. (any sympathy replies would be greatly appreciated) BTW - The reason I was working on the unit was because I was having trouble with the GG not spinning up. I took it apart to see if the motor wire was incorrectly positioned (like the said on the Letus website). The wire was incorrectly positioned so I repositioned it and the motor seemed to spin up better. Also, in the process I found a fair number of specs on some of the other internal glass pieces, so I carefully cleaned them up (Nikon cleaning solution and cloth). They looked much better and I was looking forward to seeing if I had finally gotten rid of them. Oh well....you win some you loose some.... __________________ Sony EX3, Canon 5D MkII, Chrosziel Matte Box, Sachtler tripod, Steadicam Flyer, Mac Pro, Apple/Adobe software - 20 years as a local videographer/editor

July 27th, 2009, 10:53 PM	#2
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	You have my sympathies entirely. I made a bunch of groundglass disks for a home-made a few years back and broke about half of them, mostly in the manfacturing and two in service. They were fullsized CD disks but made of glass, which when dressed down was 0.9mm thick. $499.00 seems hell expensive but this is an optical part which has to be made to precision in ten operations that I know of with a difficult raw material so there is no cheap way to do it in relatively small orders. The drilling and centering of the spindle hole is a real mongrel as is the precise mounting of the disk. In a sort of sheidenfreude way it is re-assuring at least to know that the Ultimate disk does break because we now know it is not plastic. You are to be commended for sharing this info as other owners will know the care which needs to be taken. In handling any of these devices for home repairs, I suggest owners buy a small tabletop vise or compact desktop carpenters workhorse vise to hold the body by flip enclosure so that you can use both hands on the front tube assembly when removing it and offering it back up to the body. Last edited by Bob Hart; July 27th, 2009 at 11:04 PM. Reason: error

July 28th, 2009, 07:18 AM	#3
Mitchell Lewis Trustee Join Date: Dec 2008 Location: Kennewick, WA Posts: 1,124	Thanks Bob. One last point... The clearance between the front cover/housing and the edges of the ground glass is very tight. So when you replace the front cover, just take your time and move slowly. I don't want to scare any one. The Ultimate is a well made piece. I'm no expert on taking things apart. You just have to be a little careful and move slowly. __________________ Sony EX3, Canon 5D MkII, Chrosziel Matte Box, Sachtler tripod, Steadicam Flyer, Mac Pro, Apple/Adobe software - 20 years as a local videographer/editor

August 22nd, 2009, 08:41 AM	#4
Mitchell Lewis Trustee Join Date: Dec 2008 Location: Kennewick, WA Posts: 1,124	Just wanted to update everyone. They replacement Ground Glass showed up as Letus Direct had promised. I installed it and everything has been working fine ever since. While I had the unit apart, I thoroughly cleaned all the glass elements inside the unit, and now all the specs on my footage have disappeared! The only problem I'm still having is getting the GG to spin up. Every once in a while, the GG won't spin up and I have to help it buy moving the camera rig in a circle (clients really look at me funny when I do this). I plan to send the unit back to Letus when my workload slows down. Hopefully they can replace the motor or something. __________________ Sony EX3, Canon 5D MkII, Chrosziel Matte Box, Sachtler tripod, Steadicam Flyer, Mac Pro, Apple/Adobe software - 20 years as a local videographer/editor

August 29th, 2009, 10:18 AM	#6
Mitchell Lewis Trustee Join Date: Dec 2008 Location: Kennewick, WA Posts: 1,124	Thanks Bob. I've had this problem since the Ultimate was new. I've never used the Ultimate on anything but it's highest speed setting (never really understood why I would need/want to). My additional concern would be that the GG is actually spinning at it's correct speed. If the motor barely has enough strength to get the GG spinning, how do I know that it has enough strength to spin the GG at the correct speed. I need to send the unit back to Letus in the next few months and have them swap out the motor. Maybe I'm being a worry wart, but I'm a little concerned about the future of Letus. I don't know anything, but with all the new DSLR's coming out that can shoot video, there's going to be less and less of a need for a 35mm adaptor. (I hope I'm wrong and that both technologies can exist together) __________________ Sony EX3, Canon 5D MkII, Chrosziel Matte Box, Sachtler tripod, Steadicam Flyer, Mac Pro, Apple/Adobe software - 20 years as a local videographer/editor

August 23rd, 2009, 12:47 AM	#5
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,477	Mitchell. Did the spin-up issue pre-exist the glass breakage or occur after the new glass was installed? I am only guessing here but you may need to switch on with speed set to highest and then adjust back to preferred operating speed.