Wow... I was hoping you were going to tell me I'm an idiot and to adjust some setting! I can't believe 25p looks so bad at a walking pace pan.

What was your shutter speed? What do mean by walking pace pan? If you mean like following some that is walking about 5-10m in front of the camera walking from left to right? If so, that is too fast.

The downscaled 4k is sharper. Not by much but it is noticeable.

In that case, unless there is limited motion, just revert back to 1080 50P and wait until 4K 60P becomes affordable. You might also add a little sharpening. IMHO the small loss in resolution is way preferable to the judder you will inevitably see at 25P--just like the old movies which personally I always found annoying to watch.

wwaag

....thus begins the slow transition to higher framerate acceptance... FINALLY! :D

[I]....thus begins the slow transition to higher framerate acceptance... FINALLY! :D[/I]

never understood the reluctance for higher frame rates but it may make shooting action movies more difficult because you cant hide so much anymore in motion blur.

Here's a thread from the RED users forum that is applicable to what's being discussed here.
Panning Best Practices
They mention one "rule of thumb" that I've seen mentioned on several other sites that are talking about panning speed.

The rule of thumb is to pan no faster than a full image width every seven seconds, otherwise judder will become too detrimental.

Mike

I have always been bothered by 24p in movies, that frame rate was chosen as a compromise between some reasonable semblance of motion and the cost of film stock. 25p, and even 30p, really isn't any better for capturing images with even a moderate amount of motion without judder.

Some cameras the IS also creates judder on pans - don't know about the A7sii, but if you had it on, maybe try without.

I need to do some more testing on this - As for speed of my pan in relation to the rule of thumb, I recon I wasn't far off 7 seconds for a full screen width pan. In addition to this I have also looked at some youtube videos shot in 4k which do not display as much judder as mine. I need to look at some settings and maybe post a sample of my issue if I get nowhere tonight.

I shall also look at the image stabilisation idea too.

EDIT -
Checked the raw 4k footage - fine
Checked Vegas playback - fine
Checked rendered mp4 file on PC - fine

Problem occurs only on my TV. I have always used my PS3 to deliver the content to the TV, not had an issue before as only delivered 50p. For some reason the 25p has bad judders. Not the expected slight judder, but massive judder. Hmmmm....

If I shoot 24p AND have my shutter set for 24 then I get a very smooth motion blur. If I use the default 48 shutter speed then there will be a lot of judder. But if I then want to make a DVD, DVDA wants it with the pull-down thingy and that ends up with a lot of judder even with a shutter speed of 24.

So for online and non-DVD, I can make 24p useful but for DVD, I cannot do so. I have no problems with 30p and a shutter speed of 30 going to DVD.

So much for 24 pee and 25 pee. LOL!

Actually 24 fps was chosen for sound quality from the optical track. Prior to that frames rates were often lower (in camera) until projectionists starting winding faster to get in more screenings per day. Production countered by increasing shooting frame rates. Initially 16fps was fairly standard and remained the amateur frame rate, later increased to 18fps because the safety shutter on the B&H 16mm projectors wouldn't lift at the lower speed. The standard shutter opening (camera) was 180 deg, so 24 fps it was 1/48 sec. In my early life I shot a lot of stuff at those speeds and never had a problem when the rules on camera and subject movements were sensibly followed.
However the key to smoothness is motion blur and the greater the period between frames the greater must be the blur, a matter a bit at odds with high resolution. If the camera is tracking a moving subject we usually watch the subject and that will look smooth, but should we transfer our attention to the background then that will look very juddery. We tend to see what we expect to see.

Have you looked at the rendered file properties in Mediainfo to see if the expected frame rate is there? I bring this up because I have found several render templates in which, if the render frame rate matches the project frame rate PLUS the "allow source to adjust frame rate" box is checked, will produce a file that is 1/2 the expected frame rate.

He just said that the problem seems to be with his TV!