Blurry Text N64 Optimized

[Fnnrqwin]

I have a pre-deblur N64 RGB board modded onto my system. The resulting image is pretty blurry outside the optimized modes. But I am running my N64 through the OSSC using the Firebrandx OSSC profiles, with the only difference being the 240p Sampling Phase set at 90 degrees.

I don’t really notice this as much in other games, but in Ocarina of Time I have blurry text only in some areas of the screen. Text outside those areas appears clear, and any adjustments I have attempted to make do not seem to really fix the issue. Has anybody else run into this, and do you have any settings suggestions for me to try?

Screenshot, Google Drive

Notice the difference in clarity between “Return” and “Save.” Any text in the B and A button icons appears blurry. Notice the difference between the 21s for the arrows in the C button icon area and in the item menu. Or the ammo counts throughout the item menu.

Is there any reason for this?

Here are my settings:
Video LPF: Auto
Sampling Phase: 90 degrees
H. Sample Rate: 386.85
H. Synclen: 31
H. Backporch: 27
H. Active: 320
V. Synclen: 3
V. Backporch: 14
V. Active: 240
Analog Sync LPF: Max
Line 5x 1600×1200, 320×240 optimized

[Harrumph]

Crystals have quite a lot of variance, especially with age. It’s not impossible your h.sample rate needs to be adjusted quite a lot from the “ideal”.

[Fnnrqwin]

Is there anything you’d suggest as far as how to adjust this. I’ve tried cycling through each incremental adjustment (.00 to .95) on each possible phase option. I’ve also tried each phase option on each of the closest H. Samplerate options (the five closest in each direction). None seem to help. I’m not sure if there’s some tried and true method to dial this in since there aren’t test patterns available for the N64.

[Fnnrqwin]

If anybody else has an N64 with Ocarina of Time and is using a de-blur setting on the OSSC, can you post a screenshot of the menu screen? I want to know if fixing this is even possible. I used grid patterns on my Everdrive and everything looks fine.

[Calle W]

First things first, de-blurred N64 content will look the best at 1280×960 (4x mode), since the optimal sampling rate is 386.75 (386.75 * 4 = 1547). The OSSC will round to the nearest integer, so it won’t be perfect in 5x mode.

Also, by pre-deblur N64 RBG board, do you mean Tim Worthington’s board or a simple amp mod using a THS7314 chip (or similar)? If there is a Video LPF higher up in the chain, you want to disable the Video LPF on the OSSC, since it affects phase settings. A THS7314 chip will already have one. However, a THS7316 chip doesn’t have a filter and a THS7374 might have it turned off or on. If I remember correctly the Tim Worthington boards use a THS7374 with the low pass filter enabled. Make sure you only have one filter in the chain before dialing in settings. The “Auto” setting on the OSSC will never turn the filter off, so make sure it’s set to “Off” if necessary.

One thing that you can also try is to turn off “Allow TVP HPLL2x” in Sampling opt.

On: Enables 2x H-PLL, generally reducing jitter at the price of inaccurate sampling phase due to internal bug. [default]
Off: Disables 2x H-PLL, which might help with Line5x stability.

It usually doesn’t matter much, but for accurate sampling phase for the N64, I’ve found it to be necessary.

Another thing is that text has a tendency to look bad with de-blur. Especially games that render in 640×240 (GoldenEye for example, which looks terrible with de-blur). For these titles you’re better off using the generic modes. While there are optimal timings for 640×240, it just doesn’t look great. OoT should look fine for the most part though, since the text is very blocky.

Results at 5x should look a little better than in the picture you provided, but it will never be 100% perfect. 4x will be much closer to a perfect result. PAL consoles also look the best at 4x since the optimal sampling rate is very close to 397.25.

Give the settings I mentioned a try and see if results improve.

[Fnnrqwin]

Should probably update where my settings are:

Video LPF: Off
Analog Sync LPF: Max
Allow TVP HPLL2x: Off
Allow Upsample2x: Off

H-Samplerate: 386
H-Samplerate Adj: .85
H-Backporch: 27
H-Synclen: 31
Sampling Phase: 348

I tried out 4x instead of 5x and honestly the results were pretty much the same. Tried adjusting samplerates, snyclen, and phase and didn’t get any closer to it looking clearer.

I don’t have a TW board. Just a simple amp mod.

[Calle W]

Alright, then it might be the crystal that is causing issues. Or, OoT just doesn’t like de-blur. I don’t have an NTSC copy of the game, so I can’t really try it on my own.

Below is an example using SM64 at 4x with the following settings. The console is modded with a THS7314. The is no blurriness in the center.

Video LPF: Off
Analog Sync LPF: Max
Allow TVP HPLL2x: Off
Allow Upsample2x: Off

H. samplerate: 386
H. samplerate Adj: .75 (or 3 on older firmware)
H. backporch: 35
H. synclen: 22
Sampling phase: 135 (this varies from console to console)
V. backporch: 14
V. synclen : 3

Super Mario 64, de-blur

[Author]

Posts