JeffKB
02-07-09, 05:23 PM
My IN76's power supply died recently, and after being projector-less for 3 weeks I received it back from the repair shop on Thursday. Although I was happy to confirm the power supply was fixed, I was very annoyed to discover that I now had 5 very nasty and noticeable dust blobs. My assumption is that the rigors of shipping had dislodged some dust, and it had settled on the DMD. The shipping box caused the projector to be positioned in a vertical orientation, with the lens facing up. Any dust that was shaken loose inside the optical chamber would have landed right on the DMD window.
Unlike the 4805 and X1, Infocus' IN7x series seems to be pretty dust resistant, and I could find no info on how best to get to the DMD and clean it. I rolled up my sleeves and gave it a shot today, and it went very well. I no longer have any blobs.
The IN7x series are forgotten projectors on this board, they generate very little discussion, but I figured I would post this in case anyone who does happen to own one runs into the same problem and needs info or help.
OK, here goes. There are 4 steps to getting rid of the blobs:
1. Remove top cover
2. Remove lens assembly
3. Clean DMD chamber
4. Reassemble projector
1. Remove top cover
Start by flipping the PJ on its top, so the bottom is facing you. Remove the lamp cover and lamp (see manual for instructions).
Next, remove the 6 screws that attach to the side panels (3 on each side). Then remove the 2 larger screws that are in recessed holes that are towards the rear of the PJ. These 2 larger screws hold the silver side facings in place. With the screws removed, you can slide the silver panels off, revealing 3 more screws on each side panel to remove.
When those are out, remove 3-4 screws (forgot exactly how many) that are accessible in the lamp compartment (front of PJ), that hold the top panel to the bottom panel.
Now flip the PJ over, so the top is facing up. You should be able to remove the side panels, and then the top panel. When removing the top panel, be careful because there is a wire connecting the top panel to the bottom panel (for the controls). You don't want to yank this loose.
2. Remove lens assembly
Start by removing the silver lens cowell (2 screws). Then remove 3 screws at the front of the PJ that connect the bottom panel to the interior. This is necessary because you will need to bend and pry the front of the bottom panel away from the lens, so you can get a screwdriver to the screws that hold the lens in place.
There are 3 screws that hold the lens. As mentioned, the bottom 2 will require that you pry the bottom panel away a little so the screwdriver will reach. When the screws have been removed, gently pull the lens assembly out of the projector.
3. Clean DMD Chamber
With the lens removed, the DMD window will be visible at the back of the chamber. It is a rectangular glass window about .75" wide. In my case, there was particulate matter clearly visible on it - the source of the blobs.
For compressed air, I used a product called AirDR, which claims to be oil free. I first blasted a handheld mirror, just to make sure there was no residue deposited, and when that looked OK, I sprayed the DMD window.
After spraying, I could no longer see the dust particles, so I figured I was good. If that had not worked, and I still had particles, I was prepared to use a swab with lens cleaning solution on it. People have done this successfully in the past, although it certainly has somewhat more risk.
4. Reassemble Projector
Reassembling the project is pretty straightforward, you just reverse what you did to get it apart. There is one tricky part I wanted to cover however:
The only tricky part is making sure you get the lens assembly reassembled properly with the zoom and focus gear controls. The 1st thing to do is to put the lens assembly back in, and then start tightening the screws. While there is still play with the lens, make sure you have the lens' zoom and focus in the proper position before it is tightened down and the gear teeth have meshed. In other words, you want to have the full range of motion with both controls. If you have the zoom and focus maximized on the lens, but the control is set for minimum, you won't have full range. This may sound confusing, but it is easier than it sounds, and will make sense once you start doing it.
Once the assembly is screwed back on, and the controls set right, you now need to put the top cover on so that the zoom and focus controls on the top cover fit properly with gears below. First the zoom. Move the gear so that the zoom is at an extreme. Then, on the top cover control, move the zoom ring so that it is at the same extreme. This will cause the pin in the control to match up with opening in the gear bar.
After that, for the focus control, just match up the position of the opening with the position of the pin in the top cover control, and then put the top cover on the unit.
Pictures
I didn't think to take any picture until I had already started to reassemble the projector, but I did take some and they are attached below.
In conclusion, this turned out to be a pretty straightforward procedure, and IMO was easier than the similar procedure on the 4805. It was a PITA to get the 4805's front grill off since it had tabs that just did not want to release. No such problem here. Matter of fact, if you are finding yourself trying to force something, or trying to get a part to pop free and feel it may break soon - stop. There are no tabs that are hard to release on the IN7x, and that means you are doing something wrong.
Unlike the 4805 and X1, Infocus' IN7x series seems to be pretty dust resistant, and I could find no info on how best to get to the DMD and clean it. I rolled up my sleeves and gave it a shot today, and it went very well. I no longer have any blobs.
The IN7x series are forgotten projectors on this board, they generate very little discussion, but I figured I would post this in case anyone who does happen to own one runs into the same problem and needs info or help.
OK, here goes. There are 4 steps to getting rid of the blobs:
1. Remove top cover
2. Remove lens assembly
3. Clean DMD chamber
4. Reassemble projector
1. Remove top cover
Start by flipping the PJ on its top, so the bottom is facing you. Remove the lamp cover and lamp (see manual for instructions).
Next, remove the 6 screws that attach to the side panels (3 on each side). Then remove the 2 larger screws that are in recessed holes that are towards the rear of the PJ. These 2 larger screws hold the silver side facings in place. With the screws removed, you can slide the silver panels off, revealing 3 more screws on each side panel to remove.
When those are out, remove 3-4 screws (forgot exactly how many) that are accessible in the lamp compartment (front of PJ), that hold the top panel to the bottom panel.
Now flip the PJ over, so the top is facing up. You should be able to remove the side panels, and then the top panel. When removing the top panel, be careful because there is a wire connecting the top panel to the bottom panel (for the controls). You don't want to yank this loose.
2. Remove lens assembly
Start by removing the silver lens cowell (2 screws). Then remove 3 screws at the front of the PJ that connect the bottom panel to the interior. This is necessary because you will need to bend and pry the front of the bottom panel away from the lens, so you can get a screwdriver to the screws that hold the lens in place.
There are 3 screws that hold the lens. As mentioned, the bottom 2 will require that you pry the bottom panel away a little so the screwdriver will reach. When the screws have been removed, gently pull the lens assembly out of the projector.
3. Clean DMD Chamber
With the lens removed, the DMD window will be visible at the back of the chamber. It is a rectangular glass window about .75" wide. In my case, there was particulate matter clearly visible on it - the source of the blobs.
For compressed air, I used a product called AirDR, which claims to be oil free. I first blasted a handheld mirror, just to make sure there was no residue deposited, and when that looked OK, I sprayed the DMD window.
After spraying, I could no longer see the dust particles, so I figured I was good. If that had not worked, and I still had particles, I was prepared to use a swab with lens cleaning solution on it. People have done this successfully in the past, although it certainly has somewhat more risk.
4. Reassemble Projector
Reassembling the project is pretty straightforward, you just reverse what you did to get it apart. There is one tricky part I wanted to cover however:
The only tricky part is making sure you get the lens assembly reassembled properly with the zoom and focus gear controls. The 1st thing to do is to put the lens assembly back in, and then start tightening the screws. While there is still play with the lens, make sure you have the lens' zoom and focus in the proper position before it is tightened down and the gear teeth have meshed. In other words, you want to have the full range of motion with both controls. If you have the zoom and focus maximized on the lens, but the control is set for minimum, you won't have full range. This may sound confusing, but it is easier than it sounds, and will make sense once you start doing it.
Once the assembly is screwed back on, and the controls set right, you now need to put the top cover on so that the zoom and focus controls on the top cover fit properly with gears below. First the zoom. Move the gear so that the zoom is at an extreme. Then, on the top cover control, move the zoom ring so that it is at the same extreme. This will cause the pin in the control to match up with opening in the gear bar.
After that, for the focus control, just match up the position of the opening with the position of the pin in the top cover control, and then put the top cover on the unit.
Pictures
I didn't think to take any picture until I had already started to reassemble the projector, but I did take some and they are attached below.
In conclusion, this turned out to be a pretty straightforward procedure, and IMO was easier than the similar procedure on the 4805. It was a PITA to get the 4805's front grill off since it had tabs that just did not want to release. No such problem here. Matter of fact, if you are finding yourself trying to force something, or trying to get a part to pop free and feel it may break soon - stop. There are no tabs that are hard to release on the IN7x, and that means you are doing something wrong.