Not satisfied with the colors/contrast of a CTM-644 monitor

[keropi]

Hiya!


Today I installed zaxon's internal usb floppy emulator (excellent device btw) in my 6128 and I was able to finally load something else than the basic screen 
I can't say though that the image quality impresses me... I can't quite put my finger on it but it seems that contrast and/or colors are not correct or something. The screen looks kind of dull. I haven't seen even another color CPC display so I can't say if that's normal or not - compared to my 6128plus with a scart cable the CTM-644 pales.


I tried to get some pics but as always it's difficult to capture a CRT:































The monitor has had a cleaning and a recap with quality capacitors , same for the 6128. No other problems other than that. Pics are taken with the side brightness know almost maxed-out, else the image is really really dull and unimpressive.
Is this normal? Can you detect anything on the shots I took? I kinda feel the lopt needs some focus adjustment as well.


Tips/ideas/recommendations are as always hilghly appreciated and welcomed 

[TotO]

Switch off your light! 

[keropi]

are these any better ?

[00WReX]

Honestly, from the pictures you posted, I cannot see a problem.
They look fine / normal to me.

I don't have a Plus, but of all the other 8-bit machines I have and the CRT screens I have, I don't believe I have seen much (if any) better either.

Cheers,
Shane

[Bryce]

That looks pretty normal, you've just got used to modern TVs that over-do the colours and sharpness (and this crap new HDR craze is going to make things even worse!).

Bryce.

[keropi]

I only took interest in 8bit homes this year and atm I only have a 6128 and 6128plus. Before that it was only pc/amiga and 8/16/32bit consoles for me.


Have a look at how Super Cauldron title screen looks on my 1084S with the PLUS:







and ofcourse the unfair comparison with how Prehistorik 2 looks on the PLUS:





There is just no comparison between the 1084/PLUS and CTM-644/6128 quality. That is why I made this thread, if this is normal behaviour then not much I can do but maybe there is some adjustments I can make - the setup was second hand so noone know what happened in the past 

[keropi]

Allright, after some minor adjusting the LOPT Brightness the results are great - turns out it needed some fiddling. Now reds are really red and not that deep redish mud color 

I still would like to be able to adjust contrast a little as I believe it would improve things further but I can't find if there is such a control.


It might not look like much on the pic fut the difference is there , things just look better.

[||C|-|E||]

It looks actually nice!

I still wonder why all the Amstrad CRTs I have ever tried or seen have that purity problem in the top right corner 

[keropi]

Really? Mine needs some deguassing because there is discolorarion on the top right corner as well! It is not vissible on the pics but there is a small issue there.

[||C|-|E||]

All the Amstrad screens I have checked have it, yours as well, but not worse than any other. In your case you see a little bit of purple haze in the Super Cauldron screen (more visible in the case of Prehistorik) but nothing important  . I have a degaussing coil here and, although it improves when you use it, it comes back after a while 

[keropi]

interesting... I wonder why it comes back... maybe a solution is to change the positioning of the tubes deausssing coil?

[Bryce]

All the Amstrad screens I have checked have it, yours as well, but not worse than any other. In your case you see a little bit of purple haze in the Super Cauldron screen (more visible in the case of Prehistorik) but nothing important  . I have a degaussing coil here and, although it improves when you use it, it comes back after a while 

You can't beat some purple haze to make a gaming session more interesting

Bryce.

[||C|-|E||]

Sure! It is lovely to go from 4K to the old good CPC video modes in a CM14  I still love the old screen, though, although I do not know very well where the purity problem comes from. I tried to correct it a with the classical magnetic strips, and they improve the issue quite something but, after some time, it comes back. Then, you remove the strip,  the purity problem becomes much worse and a proper degaussing is required  . At some point, I got used to it, it is only slightly visible in overscan 

[Gryzor]

Whoever said the original photos looked fine? They were halfway there between the CPC and a Crappy64!

[chinnyhill10]

There is just no comparison between the 1084/PLUS and CTM-644/6128 quality. That is why I made this thread, if this is normal behaviour then not much I can do but maybe there is some adjustments I can make - the setup was second hand so noone know what happened in the past 

You can't compare a CTM against a Philips monitor (which is what the 1084 is). I used to have my 6128 and Amiga running side by side. The Philips is a vastly better display. The CTM is basically a early 80's TV without a tuner. It's cheap and functional. A Microvitech CUB it is not!


Anyone who watches my Youtube channel knows I've successfully been videoing directly from a CTM and an Acorn monitor (which is again the same Philips). The Philips seems to have a finer dot pitch and a better colour rendition and better geometry. But it's a newer design and cost more so that's what I'd expect.

[chinnyhill10]

I have all the invoices for my new Acorn stuff including the Acorn monitor. As I mentioned it's a rebadged Philips and is nearly identical to a Commodore 1024. The invoice is dated 1990 and the price (with teacher discount) is £230.


So to put that into perspective a CPC 464 with colour monitor was £299, the standalone Acorn monitor was £230.


You get what you pay for. It's not the CTM is bad. But it was built to a price in 1984 (the design was only revised to accommodate a 12v supply) and you are comparing it with a modern modern design which probably cost nearly twice as much to build.

[keropi]

I won't argue that the 1084 is a better display (because it is - as expected since it's a newer monitor) but my CTM needed some LOPT brightness adjustment. After that it became stellar once again.
The difference in display quality was really huge to let this go unnoticed even when taking into account the age difference , I was not expecting wonders but the quality before the adjustments was just unacceptable (and pictures didn't quite capture it).
I have long-term loaned the system to a friend that was an old cpc user and he always comments how the CTM is really nice 

[chinnyhill10]

Had some kids visiting today so broke out the 464 and Acorn monitor. Oh my, the 464 looks gorgeous on the Acorn/Philips display!


Let the kids load up some tape games. They were transfixed by Kwik Snax. Really lovely seeing a 7 year old and a 10 year old sitting in from of a 464 with a zip stick playing on a CRT with not a mobile phone game or Xbox 360 in sight.

[chinnyhill10]

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[Gryzor]

Colours indeed look glorious Happy day!