methcat 0 Posted February 12, 2008 while both of my live images (day and night) seem pretty clear (focused), i notice that i get more compression noise (mpeg4) during the night shots. are there any generalities for helping the compression algorithm not get go confused, ie, add more light, raise/lower gain, etc? or, does anyone have any good resources to point ot on the subject matter? Share this post Link to post Share on other sites
rory 0 Posted February 12, 2008 More light helps, but it also depends on the camera, some cheaper ones will produce alot of noise under just a little bit of low light, while more expensive ones, typically with better Chips, could not have any noise until it the light gets much lower, in some cases near pitch dark, such as with Exview Chips (there are several variations of each chip also, cheap to expensive). Anyway, more light the better. Be forewarned though as the image gets even clearer, it can take up even more hard disk space as the image maybe larger. Share this post Link to post Share on other sites
methcat 0 Posted February 12, 2008 i have one of the pleco 1390 day/nights. the night image looks fine and free of noise when i watch it live, i'm just thinking that the noise is comming in during the dvr compression. i guess what i'm asking is, is there prefered conditions that will give the dvr less headache. ie, do brighter or sharper or any other type of scenes help stop some of the artifacts of the software/hardware compression. Share this post Link to post Share on other sites
rory 0 Posted February 12, 2008 What compression is the DVR set to? Share this post Link to post Share on other sites
Kiwi 0 Posted February 12, 2008 I've noticed a similar issue. Basically I've found: "garbage out" = ("garbage in") squared The compression algorithms really work best with the smoothest image, free as possible of CCD noise speckles. So basically it boils down to enough light to lower the noise level as much as it can go. Share this post Link to post Share on other sites
methcat 0 Posted February 13, 2008 kinda what i figured, just wondering if anyone had a particular easy trick to make it better. granted i'm only running one of the cpcam 501's and i know what to expect for my money. i probably woudn't even have questioned it except for that the daytime recorded/compressed picture, and the live picture for both the night and day scenes look acceptable to me. btw, i'm running what "cpcam" calls D1 fram, at best, and it does mpeg4. i have the pelco, ir corrected F1.1 lenses and good cabling. i really think it's all in the poor(er) compression, but i also realize there are things you can still do to help smooth it out... thanks for the input, it's much appreciated, Share this post Link to post Share on other sites
rory 0 Posted February 13, 2008 Also, a little bit of noise will be alot more noise when recorded, even moreso on some cheaper DVRs. Reason they cost much less is they dont spend the extra time the more expensive ones do on the extra features. Share this post Link to post Share on other sites
mikesus 0 Posted February 14, 2008 I can definately say that if you don't have a good signal in, the compression makes it much worse. When I switched to a WV-CP484 I found that I was getting images that are just as good as daytime. Share this post Link to post Share on other sites
Stanislav 0 Posted March 10, 2008 New VideoCAD6 version allows to model camera sensitivity parameters and choose optimal ones for existing light condition or choose required illuminators and their positions. The model includes minimum scene illumination, ES, IRE, S/N ratio, AGC, BLC, lens aperture, compression... etc http://cctvcad.com Share this post Link to post Share on other sites
zmxtech 0 Posted March 10, 2008 A "pro" installation wont have any noise ! Yes its a trade-off compression vs size, but then disks are cheap now run it raw -uncompressed or bitmap and you wont go back. The lighting is half the equation not just the camera. for example I might install camera X a bit of noise at night not too bad but a re jig of the bulbs from say 60w to 80w fixed it. Or you might need another IR flood. In actual fact I noticed some of my sony EXview HAD`s need less IR light ! Now my cams are so good I can see the sky and clouds reflecting of the windows at night -sets off the motion detection -aghh you cant win... my 2.5 c Z Share this post Link to post Share on other sites
VST_Man 1 Posted March 10, 2008 how good is your night time motion pics? I've tested many cams that give great stills at night in low light but are not worth .02 when motion occurs. you get a very nice blurry pic. Share this post Link to post Share on other sites
methcat 0 Posted March 10, 2008 well, the motion is fine. not too much blur or jaggies. the live feed is good at night, so i think the cameras are ok. i've been noticing that on darker nights (no moon) the compression noise on the dvr gets worse, so i'm kinda guessing that's it. i think the gain is probably messing with it too. i should probably turn it off and see if i can still see... Share this post Link to post Share on other sites
