Is it normal that the spotsizes of the tubes differ a little?

I have done the focus and astigmatism as good as possible and when I do maximum underfocus green has a much bigger blob than red. Also in focussed mode I can see a little difference but not much.

Is this because green also seems to have a litle bit more wear perhaps?

Optical they are both optimal focused.

Short adition,
I think the astig on the tubes is very good because there is no motion when I change focus and the defocused image is very sharp and round with a white point in the middle.

But whatever I change green is allways a little larger than red. I have tried moving the focus coil but that did not work.

I ask this question to know if I have to look further or just accept this as a consequence of wear? (there is just a very little wear on the tubes)

Yes, my XG is similar.

Some tubes are sharper than others. And more to the point, the auto defocus for astig varies in affect on different tubes it seems.

Is it possible that it has something to do with the G2?

Last night I was setting astigmatism on my Runco 933 and yes spot size is not the same on all tubes. My shows blue as the largest one and this is the tube with out of any signs of wear. I have only 1700 hours on this projector.

Runco 933 is a great crt in my opinion. I have it almost two years now and astigmatism is very important to get a sharp 3d like picture.
I folowed some instructions on this site to maximise the fosfor. The test image is realy on the edge of the tube therefore I'm not displaying it to long, the real image is much smaller and with a little blanking I now use 100% amplitude, the raster is absolute in the middle of the tube and I checked that after every change by looking in the tube with sunglases.

It might be that experts would not advise to use 100% horizontal amplitude but it looks great, over 8 inch :)

Add a fan to your deflection heatsink RedFox...

Good point! I'll also keep an eye on the temperature, that might be a risk with 100% width :confused:

This problem with the spotsize is still bothering me.

I have tried the astigmatism rings, the position of the focus coil on the tube and of cause the electric and optical focus. But still green is larger. The consequence is that I have to lower contrast to get the grayscale flat because red tents to saturate earlier than green.

Is there realy no other way to change the spotsize? Might it be a wrong G2? How could I check G2 on nec 9 pg xtra?

Thanks

Thinking about this it is probably wear the tubes can be rated 9 8 9 with green being 8. The next question I have is what kind of tubes do I have to look for and is the best place ebay? I think the nec 9 pg xtra has sony tubes? Hmmm I read that green is not likely to get and that the g2 is very complicated but probably still right.

Do others also see that the tubes with most wear have largest spotsize?

Blue tubes are generally inherently the tubes with the least focusing ability. I found on my Nec the next was the green and then the red. If your CRT's wear is 9,8,9, there is no reason to replace the CRTs. In any case, they are hard to find and would be pricey.

I think you're right, the tubes are fine. The only upgrade that I'm considering now is to get an 1.3 gain screen. That will give me a more dynamic picture but on the other hand I'm allready enjoying the picture very much right now and I don't have to worrie about lamps getting dimmer and losing all ther light in a few hours like the digital :-)