Which TV: Digital geometry controls or analogue geometry controls?

[rtyp3r]

Hello,

I have two sony trinitron RGB SCART TVs to choose from and don't know which one to take:

1). First TV (KV-29FX30E) has a service menu in which I can correct picture geometry by using the tv remote.

2). Second TV (kv-x2531d) has analogue thingies (phillips screws) placed on a board to manually correct picture geometry. The board is inside the chassis and is not easily accessible and Id like to somehow to modify screws so I can extend them to more accessible place (in front of the cabinet) where I could easily adjust picture geometry with a screwdriver.

Which TV would you choose?

I have tried the first one and found it very difficult to change the geometry by tv remote every time after a game resolution is changed.

[rCadeGaming]

1.  You will get a lot more flexibility to fully correct your geometry with a digital service menu, but I would not recommend trying to adjust it with the remote every time you switch games, (although you might be able to get horizontal position control by simple running the c sync line you're plugging into the TV through a pot).  Use a test pattern to set it to a happy medium which will be a good compromise for all the console games you play.  If you use a PC with it, you can adjust individual resolutions at the PC end.  Also, with any digital chassis CRT you should make sure it can in fact display 240p without upscaling, meaning do you see real scanlines? 

2.  With the analog adjustment pots, they could be removed and the connection points wired to external pots with nice adjustment knobs.  This would make it feasible to adjust more often, but the amount of adjustments possible could be more limited.  Overall size and position will be simple, but what about straight geometry in particular areas, especially at the corners, and vertical linearity and s-correction.  Get a cross-hatch pattern up to see what's really going on.  There are maybe two dozen important geometry adjustments in a Sony digital service menu, and I doubt there will be that many adjustable pots.

Trying getting them both adjusted as best as possible (using test patterns is very important), then compare to see which looks best to you.  Look for color, clarity, and scanline thickness in-game, and look for geometric straightness and convergence with a test pattern.  For vertical linearity and s-correction, play a vertically scrolling game, and watch if things scroll smoothly, or if the getting bigger and smaller at different areas of the screen, appearing to warp or distort as they move up and down.

The last thing is whether these TV's are round or flat-faced tubes.  Flat face tubes are nice, and much easier to make a bezel for, but flat Sony CRT's usually have slight a horizontal bowing that can be impossible to totally get rid of without making complex physical adjustments inside with the deflection yoke and other magnets.

[Paradroid]

Go the analog controls! So much faster to adjust than digital service menus!

Have you seen how I did it here?

If the TV is well designed, you won't need all those extra digital geometry settings to get the pictures looking good.

[rCadeGaming]

Paradroid, your setup is really nice, but it depends on the sources rtyp3r will be using, and his abilities with electronics.

If this will only be for a PC-based emulation setup, the geometry on the TV should only have to be calibrated once (unless the set gets physically moved around).  Then, individual games can be adjusted for correct size and centering using custom modelines.  This way, after everything is set up, everything is automated, so you should never have to make any adjustments.  In this case, having the most flexible and powerful adjustments from a digital chassis is much more important than having them easily accessible.

If this will be for actual consoles or PCB's, having the easily accessible pots hacked from an analog chassis is very useful.  However, the problem is that although your geometry looks quite good from your reference shots, I think it is due to your skill in hand selecting a tube and especially in manually adjusting the deflection yoke.  Could you have gotten that kind of geometry just with adjustments to pots?

[Paradroid]

rCadeGaming, that's a good point. I did adjust the rotation of the yoke to get the symmetry correct and I also mixed and matched components to make sure I was using the optimum.

That said, the analog chassis TVs I've tried have had inherently better geometry and image quality than the digital counterparts. An old Grundig or Sony chassis tends to be pretty damn good without too much messing around. The digital Loewes and Grundigs I've tried (haven't tried a digital Sony) have looked good but have been far more involved in terms of tweaking. Loewes in particular take a lot of work to get the geometry right. Then, as soon as you change the vertical size you have to re-calibrate everything again. With a good analog chassis, only the vertical size changes when you shrink the frame. On the digital types, the pincushion tends to need re-adjusting.

The thing I like most about analog controls is the speed of adjustment: it's a very tactile experience with instantaneous results. The hassle of entering a service menu, adjusting and then saving changes started to drive me nuts before I made the switch to analog only.