Can I use both together?

Yes, and on busy footage it is common. Keep both restrained, because a heavy outline plus a heavy shadow starts to look like a sticker.

Why do my letters look filled in?

The outline is too thick for the size of the type. Thickness needs to scale with the letters, not stay fixed while the type gets smaller.

Which suits a face on camera?

Either works, because skin tones sit in the middle of the range. The choice matters far more on bright outdoor footage and on screen recordings.

Does this change with type size?

It does. Large type carries a heavier edge comfortably; small type gets muddy with the same setting, which is why the two should be adjusted together.

Where do I see the effect before posting?

In the preview. What the preview shows is what gets placed into the clip, so you can settle it there rather than after the fact.

Should thickness change with type size?

It has to. A setting that looks right on large text turns small text into a shape rather than a word.

Can I use both at once?

Yes, and on busy footage it is common. Keep both restrained, because a heavy edge plus a heavy shadow starts to look like a sticker.

Outline or Shadow on Subtitles?

What is the practical difference?

An outline surrounds every letter, so it works no matter which direction the bright area comes from. A shadow falls on one side only, so it fails when the bright part of the picture sits on that same side. Outline is the safer default; shadow is softer when it happens to suit the shot.

Where each one breaks down

Outline is the safer default because it does not depend on which direction the bright part of the picture comes from.

Situation	Outline	Shadow
Bright area on one side	Holds, it surrounds every letter	Fails if the bright side matches the shadow side
Bright area moving around	Holds	Fails intermittently, which reads as worse
Small type	Gets muddy if thickness is not reduced	Holds better, since it sits outside the letters
Large type	Holds well and looks deliberate	Holds, and can look soft
Letters with holes in them	Fills in when too thick	Unaffected

Choosing thickness

A thin outline can disappear at small sizes, while a very thick one can fill in the inside of letters, especially small ones. Scale outline thickness with text size, and check the smallest text in the clip.

Moderate thickness usually works best.

Combining both

An outline with a soft shadow gives text both a crisp edge and a sense of depth. The combination works on a wide range of footage.

Keep the shadow subtle so it does not blur letters.

Faces and skin tones

When text sits near a face, a dark outline on white text is usually safest. It stays readable against both light and dark skin tones and backgrounds.

Test on your typical footage.

Seeing the effect before posting

Preview the style on the brightest and darkest moments of the clip. If text stays readable on both, the choice is sound.

Save the style once it works.

Whichever one survives your footage

Find the brightest moment in the clip. That frame is where either approach is most likely to break down.
Check the letters with holes in them. Letters like e and o show a weak outline first, because the gap inside them fills in.
Prefer the one that survives movement. A choice that only works while the camera is still is not really working.

Put one real clip through and look at the brightest second of it.

Questions people ask

Can I use both together?: Yes, and on busy footage it is common. Keep both restrained, because a heavy outline plus a heavy shadow starts to look like a sticker.
Why do my letters look filled in?: The outline is too thick for the size of the type. Thickness needs to scale with the letters, not stay fixed while the type gets smaller.
Which suits a face on camera?: Either works, because skin tones sit in the middle of the range. The choice matters far more on bright outdoor footage and on screen recordings.
Does this change with type size?: It does. Large type carries a heavier edge comfortably; small type gets muddy with the same setting, which is why the two should be adjusted together.
Where do I see the effect before posting?: In the preview. What the preview shows is what gets placed into the clip, so you can settle it there rather than after the fact.
Should thickness change with type size?: It has to. A setting that looks right on large text turns small text into a shape rather than a word.
Can I use both at once?: Yes, and on busy footage it is common. Keep both restrained, because a heavy edge plus a heavy shadow starts to look like a sticker.