Detail Setting and Noise
 

A comment on another thread a little while ago raised this issue for me.

What is the relationship, if any, between the detail setting on the camera and image noise?

I standardly set detail at minimum. This (subjectively) looks best to me.

Is the detail setting a kind of digital sharpening process? At 'normal" it looks unpleasantly sharp to me.

If there is a relationship between detail setting and noise, what is the optimal setting?

Any thoughts?

Rob

Hi Robert.

Yes, the detail is indeed a digital "enhancement", basically an edge detection system. When set at 0 it's already several steps above normal. Weird but hardly a JVC exclusive.

Detail will add noise to your footage because it triggers artifacts in the compression. A setting of MIN or OFF, depending on personal preferences and scene requirements, is usually the best choice.

Sometime people feel a little uneasy about going to "negative" detail but just ask yourself, what good would do to have a detail knob that blurs the image? None. When the detail is off you end up with the image as it's acquired by the camera. Anything you add to that point, is, well, an addition. Now, RAW still photos are know for being soft and usually photographers using that system will add some sharpening in Photoshop or Aperture. I usually add a little bit. It's the nature of RAW of being in that way. I like the detail setting on my HD100 to be at MIN. It seems to me that it provides a nice image that doesn't have an artificial edge quality but at the same time has that pleasant softness that is more film-like.

Thanks Paolo for your informative post.

Just as I suspected!! Maybe the default setting is a way of boosting the "HD" credentials of the camera for the marketplace though I do not think it necessary at all. I personally do not like the look of the camera at "normal" and as I noted always have the setting at minimum.

Interestingly, my instincts are the same with my still stuff - I don't tend to like any edge sharpening at all.

Rob

Nope, not really. Detail, as Paolo stated, is a boost in signal level around dark to light transitions. The original purpose is to more or less boost the high frequencies in the acquisition process, so that by the time they got all the way through the analog signal chain to your tv set in the NTSC world, you'd still have a picture that wasn't mud. In the analog domain, each iteration will degrade the higher frequency signals first. The analog audio equivalent would be to boost the treble response at the recording point, so that several copies later, you wouldn't end up with muffled audio.

In that respect, I'm not sure we even need detail circuits any more but will have to put up with them until the move to digital is complete.

-gb-

Yes, I also leave mine on MIN. However I wonder if that would be smart if shooting for the big screen, as 720p is already not enough for big screen release and making the image softer from the get go may not be wise. I know detail is not real resolution, that's why I wonder what would be the best approach for this.

Question....when you say MIN, do you mean OFF? MIN is the first step above off on my HD110.

AS for being too soft for film, one can always sharpen in post. I use NeatVideo for noise control and sharpening. It's a great tool that's been derived from still image photography.

I agree. We are rapidly moving to a world where displays will be larger -- 60" and above -- and FullHD. 720p is inherently "soft" on such displays, particularly on wide shots. Some edge enhancement may be needed to keep 720p looking good on these displays. I can pick Varicam stuff from HDCAM and really hate the softness.

The other question -- how much Sharpness have you dialed into your monitors. I find 9 out of 10 leave it at 50%. Get an HD DVD player ($100 to $200) and an HD calibration disc and adjust Sharpness. You may well find a Sharpness level of 5% to 15% to be perfect.

Only then check your camcorder. I suspect you may find you don't want MIN.

With Sony HD camcorders, NORMAL offers a wide bandwidth and an "acceptable" amount of "overshoot." Once you lower Detail, you cut bandwidth hence you cut/smear fine detail. That's because Detail does NOT simply increase/decrease edge-enhancement. It is increasing and decreasing signal bandwidth. Check the BBC tests of low cost HD camcorders.

PS: going to film is very tricky. You can't afford to have any outline showing, but you can't afford softness either. Tests before shooting seem the only way to be safe and not sorry.

After doing some tests when I bought my jvc, I have never used more than the "min" detail setting. I did one project with it off and it was really soft, but that is why I used that setting, I wanted it really soft. For me anything above Min makes the footage more videoie. I am always trying for a filmie look for my stuff.
Here are some frame grabs from my highly scientific tests...lol.
Cheers,
Jon

http://fotgfilms.com/img/detail/0-DetailOff.jpg

http://fotgfilms.com/img/detail/1-DetailMin.jpg

http://fotgfilms.com/img/detail/2-DetailNom.jpg

http://fotgfilms.com/img/detail/3-DetailMax.jpg

My feelings exactly!

How do you feel about the HD100 in this respect? NORMAL is the way to go too like the Sonys?

Do you have a link for these tests? Could find anything on google.

Yes and if you add a 35mm adapter it gets even more tricky as the adapter may add softness, but at the same time it will also give the illusion of sharpness because you can now select your focus to a specific point. It also normally makes the image less contrasty, which some feel is more filmic, but it also means some sharpness enhancement could do good. What’s your opinion on this?

I like the Min a lot. I'll have to do similar testing myself, but I have a gig in a few hours.. I think i'll try Min. While doing sports I get a lot of edge enhancement noise on NORMAL on chain link fencing at a certain focal length. (medium zoom around 45mm) of fencing about 100 yards away. Hopefully MIN detail will eliminate most or all of it.

By comparison I pulled out my old Sony TRV-900 to look at it after all these years..... Edge enhancement like there was noooo tomorrow. Ghastly....