CurtPalme.com Home Theater Forum

deronmoped · Joined: 03 Nov 2006 Posts: 1154 Location: San Diego

So I have been working on focus lately. I have been doing that because I went to a different screen and PJ placement. After getting everything dialed in the best I could, I was getting real good focus on the green with a small amount of flare. The red was not as good, there was way more flare and the individual dots the focus pattern were made of was not real well defined. This got me thinking of how I could go about fixing this. I messed with where the focus coil and astig magnets were on the tube, but I had them in the best position already. I did notice the astig magnets were not as critical as the focus coil. The focus coil had to be dead on and the astig magnets could be moved a half inch or more without much effect. I was looking into getting some six pole astig magnets, but in the meantime I though I would just throw some extra four pole magnets I had on the tube to see what happens. What I did was set the extra set of astig's so they would be in the null position. I then slid them on the red tube up against the other astig that was already there. I fired up the PJ put up a focus pattern, there was no change in focus as I though there should be with the extra set in the null position. I then started to do some adjusting, not really expecting to see any difference, well to my surprise I was able to dial the red's focus in much better. The dots the text pattern was made of was now in much better focus, the flare was still there, but it seemed to be more uniform around the letters. "Wow, this is cool, I though, time to try the green". I put the extra magnets on the green and went to work. On the green I could not get the focus of the dots the letters were made of any better, but I pretty much removed all the flare.

The results were there in the image too, letters on my desktop were sharper, I put in the "Fifth Element", which I use all the time for comparison, and the image was noticeably sharper. I then watched a movie I had not seen before, "A Beautiful Mind", it looked super good, the edges on buildings looked very well defined, some of the shots of peoples faces looked excellent, and these shots of their faces were not super close up ones.

I wonder if there are even better astig magnets out there?

Happy camper, Deron.

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

Was this on An ehome 8xxx ?

Athanasios

Gino · Posted: Thu Dec 13, 2007 11:08 am Post subject:

So did the extra 4 pole magnets in effect make it act like a 6 pole magnet? ie. one for flare, astig, triangularity?

Perhaps your original 2 pole magnets were weak and weren't really doing anything? I find small movements on mine make a discernable difference on the screen.

deronmoped · Joined: 03 Nov 2006 Posts: 1154 Location: San Diego

Athanasios

I have a NEC 10PG.

Gino

I was wondering that myself, but I do not think so. I'm pretty sure all that is happening is I'm doubling up on the two and four pole magnets. Of course then again it may depend on how I have the extra fields working in relation to the first set of astig magnets.

The astig's I'm using are good, I have tried different sets and they all worked in the same way.

I kind of wonder why no one sells a super duper set of astig magnets. There are all kinds of other upgrades that are out there. If someone could come up with a set of astig magnets that were a improvement over what we all have you would think it would be a hot item.

I have a question, I noticed on these four pole astig's I have there seems to be a extra set of magnets, making these a six pole assemblie without the third adjustment knob, are those extra magnets just dummy magnets or can they be adjusted?

Deron.

Tinman · Posted: Thu Dec 13, 2007 4:50 pm Post subject:

2 sets of astig magnets? Now THAT is interesting.

Marc

tse · Joined: 03 May 2006 Posts: 1014 Location: Sweatbucket, Fl.

dbaisey · Posted: Thu Dec 13, 2007 6:58 pm Post subject:

2-4-6 pole that fit the 10PG.

deronmoped · Joined: 03 Nov 2006 Posts: 1154 Location: San Diego

Doug

Those look like NEC magnets. Did NEC make them? What are they used on. Where can you get them?

Deron.

Gino · Posted: Fri Dec 14, 2007 7:05 am Post subject:

Deron, Doug did say 10PG

They look just like the ones on the Marquee too

**Curt Palme** · Posted: Fri Dec 14, 2007 1:48 pm Post subject:

The 10 PG tubes have the same neck diameter as the E'homes, which is where those 6 poles came from.

deronmoped · Joined: 03 Nov 2006 Posts: 1154 Location: San Diego

Gino

Yeah, I did catch that he did say they fit a 10PG, but why does my 10PG not have them?

Curt

I did find out I was lucky in that way, that E'home stuff would swap over to my 10PG. The extra astig magnets I'm using are off some 8XXX Marquee's, or were they from some Barco's I had Rolling Eyes

It would be interesting to know if what I was able to do to the my PJ's flare, spot shape and size is repeatable with other PJ's. Someone should try it, it only took me a half hour to set the extra set to the null position, install them and put up a pattern and adjust them. I did go back and forth between both sets of astig's to get the better results.

Deron.

dbaisey · Posted: Fri Dec 14, 2007 10:27 pm Post subject:

Deron,
When the 10 PG was made they didn't have the 6 pole. It was basically the 9PG chassis with 9" tubes. The Plus and Extra had them but 7.5 - 8" and went along with the edge separate focus and electronic astig. With the yokes in stock location the 2-4 did ok. Doug

Mark_A_W · Posted: Sat Dec 15, 2007 12:38 am Post subject:

deronmoped · Joined: 03 Nov 2006 Posts: 1154 Location: San Diego

Doug

So those are too small in diameter to fit the 10PG tube neck, I would have to go with some six pole astig's off a Marquee.

I have another question.

I can optically focus the flare out of the red tube, but I start to lose the definition of the dots the letters in a focus pattern are made of. What is happening here? Is the sharpest part of the focus pattern at a certain level of the phosphor along with the flare. When I optically focus out the flare, I'm focusing on a level of the phosphor that the flare does not make it too? Or could there be something going on with the optics on the red tube? Fungus, dirty lenses/C-element...

Deron.