That is very sad....
Thank you for very quick answer.
Which render settings should i use to get the the best (nearly untouched) result?

I follow this extremely complicated workflow to smart render my Panasonic GH4 clips. You can also access the underlying ffmpeg smart rendering functionality by using custom commands in Vegasaur Smart Trim.

You may be able to smart render your footage using TMPGEnc MPEG Smart Renderer 5. You could probably also use a script to write out an EDL-style list from Vegas that TMPGEnc can use to render a batch.

Staying in Vegas, here are some options, approximately ordered from biggest file size down:

• UT Video Codec - 3rd-party lossless VFW codec
• MagicYUV - 3rd-party lossless VFW codec (smoother in Vegas and smaller file size than UT in my tests but I get very occasional sequences of black or corrupted frames)
• Sony YUV - High-quality VFW codec included in Vegas
• Cineform - 3rd-party near-lossless (some say "visually lossless") VFW codec obtained by installing GoPro Studio
• Grass Valley HQX - 3rd-party high quality VFW codec (Grass Valley HQ may also be relevant. Not sure)
• XAVC Intra - High-quality modern codec included in Vegas

I can't say whether these formats will play correctly in your media player. They would all be in an AVI wrapper apart from the last one which will be MXF. They'll all be significantly larger in file size than your source footage. For a smaller file size than this, other options open up, such as the other XAVC options, or MainConcept/Sony AVC/AAC at high bit rates. Or you could try re-rendering very high quality AVC using the x264 codec via the Staxrip, Handbrake or MeGUI GUIs. Vegas2Handbrake can help.

Can somebody give me some hints to find the correct render settings for smart rendering? I want to create video clips for some media player, not for BR-Discs.

Due to the file size generated by all of the codecs listed by Nick this will not be a solution for the typical media player, since the files will be much too large and will not be supported by the player!

For the media player you will need formats like H.264 long GOP, as delivered by the Sony AVC or the Mainconcept AVC encoder. Sure there will be rendering losses, but do not beliefe that you can avoid that really. Even if you render to the codecs listed by Nick, you will have always losses due to decoding.

So if you wish to render for media player, then either use the Vegas internal codecs (the losses will not be soo significant), or use the codecs listed by Nick. Some of them can be transfered to an external encoder (for example TMPGenc). Or use Handbrake.

Another solution could be to use not Vegas but a third party tool, what supports smartrendering (as long as you do not need any corrections for luminance or chrominance that could work too). Up to you.

There is no futher solution inside Vegas I think, since the development team of Vegas decided long time ago not to support Smartrendering for H.264 I think.

Thanks also to Wolfgang.
In future i would like to go a easy way. I am tired of testing all the available default formats and to change render details...
I read that Cyberlink PowerDirector uses smart rendering for AVCHD. But i am using a nice plugin in Vegas named svdts3 to get the date/time when a new clip begins. For me this is a must have feature.

Other Question:
I recorded some clips in PS quality (28Mbit/s, 50p). Vegas do not recommends me the Sony AVC or the Mainconcept AVC codecs, only XAVC. I do not like the XAVC because the file size goes from 300MB source to 800MB.

I recorded some clips in PS quality (28Mbit/s, 50p). Vegas do not recommends me the Sony AVC or the Mainconcept AVC codecs, only XAVC. I do not like the XAVC because the file size goes from 300MB source to 800MB.

So those PS files are AVCHD files? I would generate a render template for the Sony AVC encoder, with 50p. And use that.

Yes, screenshots attached.

Generate within the Sony AVC encoder a 1080 50p template, and use that.

Example below

here is my

Data rate should be set to the maximum since 1080 50p will require that.

here is my

Today i checked the template from Wolfgang. File size is OK, quality for first review also OK.
But my setting window looks a little bit different:

Sure to increase data rate is fine, and I have used that in the past too (no idea why my datarate was lower. Go to the maximim possible here!). 

Short feedback to my last comment.
As raw setting template i used the "AVCHD" template. But i got 2 problems with the generated video files. The windows VLC player can only play the first 2 seconds, then the picture stops completely. The audio is played correctly. When i open the video file via Amazon FireTV Box using KODI, the video starts to judder after some seconds.

Then i used the "Internet" template and modified it to 50p. The generated video files can be played without problems on VLC and KODI.
Any explantations for that behaviour?

Wenn ich das richtig deute, ich habe mit V14 ähnliches Problem, wenn ich das Sony-Material rendere in AVC Stream dann den Ton ausgebe als AC3 und beides zusammen muxe mit MKVToolnix nach ein paar Minuten/ Sekunden ruckelt das Video, spulen hilft weiter, bis wieder nach ein paar sekunden Bild ruckelt, obwohl mein Mediaplayer POPCORN A400 das gleiche File mit V13 abspielt

Short feedback to my last comment.
As raw setting template i used the "AVCHD" template. But i got 2 problems with the generated video files. The windows VLC player can only play the first 2 seconds, then the picture stops completely. The audio is played correctly. When i open the video file via Amazon FireTV Box using KODI, the video starts to judder after some seconds.

The judder issue was identified since some years ago. After rendered to AVCHD, you need to do M2TS muxing with small application called tsMuxerR:

Ref 1: https://www.vegascreativesoftware.info/us/forum/rendering-problem-avchd-1920x1080-60i-5-1-surround--92989/

Ref 2: https://forums.creativecow.net/thread/24/896708

As stated by the tsMuxeR app:

Network Optix tsMuxeR. Version 2.6.12. www.networkoptix.com

Decoding H264 stream (track 1): Profile: High@4.0 Resolution: 1920:1080i Frame rate: 25

H.264 muxing fps is not set. Get fps from stream. Value: 25

B-pyramid level 2 detected. Shift DTS to 3 frames

Decoding AC3 stream (track 2): Bitrate: 192Kbps Sample Rate: 48KHz Channels: 2

Processed 3750 video frames

Flushing write buffer

Mux successful complete

Muxing time: 9 sec

das mit dem durch den tsMuxer ist eigentlich bekannt, wenn man in V13 in sony m2ts gerendert hatte ruckelte es nach 1 paar sekunden, einmal tsMuxer und danach ging es, darum renderte ich in AVC sound extra ac3 anschließend mit mkvToolnix eine MKV fertig, mit V14 muss man den fertigen scheinbar nochmal in den tsMuxer, Fackt ist hier aber, dass Magix was im AC3 oder im AVC Code etwas zum negativen geändert hat, darum bitte um Änderung, habe auch schon Ticket geschrieben, schaun wir mal

Sorry, aber das Problem mit dem Ruckeln ist m.E. kein Problem von Vegas sondern ein Problem des VLC Players, der schon immer Probleme mit einigen AVCHD Dateien hat.
Viele Player spielen auch mit 26 MB gerenderte AVCHD Dateien ohne ruckeln oder Bildausfall problemlos ab.

(warum eigentlich so ein englisch/deutsch Mix hier?)

The tsMuxeR tool fixed my problem, thanks!

Which Sony AVC/MVC output format you would prefer after rendering with vegas?
AVCHD 1920x1080-xxx (*.m2ts) or Internet 1920x1080-xxx (*.mp4)?
What are the differences?
 

If you want to keep a 'final master render' (my personal terms) of your edit, then you can render it to AVCHD. And I notice you are working with interlaced footages (50i). And media player devices can read these files (PS3, Blu-ray media players with usb flashdisk media support). But, for more gadget compatibility and internet upload purposes, Internet template MP4 is more preferred - you have progressive 25p movie file. Also, you can adjust the bitrate as needed.

I prefer m2ts, think it has a little better quality
The difference is the codec which is used

@set,
As i wrote in first comment, i want to have my recordings nearly lossless rendered. So i should use the m2ts format and after rendering to run tsMuxR?

@set,
As i wrote in first comment, i want to have my recordings nearly lossless rendered. So i should use the m2ts format and after rendering to run tsMuxR?

Yes. 

My first recordings are in 50i format. In future i will record only in 50p. But i need a good, nearly lossless setting template for my 50i recordings. Any suggestions?

Recoding parameter:
Video codec: H264 - MPEG-4 AVC (part 10) (h264), 1920x1080, frame rate 25,  Planar 4:2:0 YUV, 24Mbit/s
Audio codec: A52 Audio (aka AC3) (a52), 3F2R/LFE chanels, 48000 Hz, Bitrate: 448 kB/s
Sony quality description: AVCHD FX, 50i, 24M