hmc40 a bit grainy

Thomas Smet

Thomas Smet

Veteran
Anybody notice their HMC40 a bit grainy when shooting 0 db in bright sunlight. I love my camera but I'm really starting to suspect there may be something wrong here. I shot some material in bright sunlight and at 1080p it sure does have a lot of noise. Last night I did a test where I shot a dark room at 0 db and sure enough there was a lot of noise. Am I just doing something wrong with this camera.

I had a SONY HC1 before this and while it sucked pretty bad once you had to start using gain if I kept the camera near 0 db it would be super clean. I have had a few people now comment to me about the noise with the camera and I'm starting to wonder if this thing is working the way it should be.
 
I find that at 0db the HMC40 produces one of the cleanest images I've seen out of any consumer/pro-sumer camera yet. Can you post some footage?
 
Yeah I will try to post some tonight. I'm at work right now and I teach at a college after work so it may not be until much later tonight. I have my iMac at work with me but I don't think I have any examples of the footage at 0db here with me.
 
Good call on the DRS, Barry... I disabled that right after unboxing my HMC40 because of the noise in the dark bits.
 
I just checked and yes the DRS is disabled. I had really hoped that was it.

Anyway here are a few images I know were shot at 0 db. In fact the shots of the dog outside were right on the edge of closing the iris because it was so bright out. I really miss having a ND filter on the camera. I also included a shot of my desk in a very dim room shot at 0 db. This is what really started my concern.

hmc40_01.jpg

hmc40_02.jpg

hmc40_03.jpg


Thank you again for any help or feedback.
 
Keep in mind all of these shots are 0 db. Regardless of the camera 0 db should be clean. Yes the HMC40 is darker but it should at least be clean at 0 db. I do not doubt at all that the HMC150 would have a brighter image but would it really be any cleaner at 0 db.

This also does not explain the grain in the perfect daylight shots. Look at the door on the house in shade. This was at 0 db with the iris almost closed due to how bright it was out there. To me these shots look like other cameras shooting outdoors with the gain accidentally set to +6 or +12 db.

Now that I have been looking at this a bit closer I'm starting to wonder if this isn't compression noise.
 
What scene file settings are you using? (We especially need to know what Gamma, Knee, and Detail settings)
 
I believe these were all set to default, whatever that means. I tried to keep the camera as natural as possible when I shot this stuff. I did check to make sure DRS was off however. If I remember correctly gamma was set to HD norm I think. Detail was at the default 0 or off if that is an option. I'm not sure what the knee was set at but whatever the default value is should be what it was set at.
 
Thomas,

Your scene file settings will make a huge difference and the stock settings are pretty sucky, so that would be a poor way to judge the cam. HD-norm is one of the noisier gammas. Try B-str for starters, I think it has the least noise. Then try a master pedestal of -5 to help crush the blacks slightly, use mid knee, and cinelike matrix. Take detail to +2 and detail coring to +3. Save and restart the cam per the manual if you want to keep the changes. Compared to the stock settings, you will see a huge difference; improved detail, less noise and a moderately saturated look. I don't care to much for the cine gammas because they do seem to introduce noise, but you can selectively increase your saturation further with chroma and chroma phase.

If you experiment, you will find your own look, but what I gave you above will get you started for a nice basic look for outdoor work. Also, how are you making the judgements about your screen shots. If you are using the viewer in your editor, that may not give you good resolution. For comparison, try using a HDMI direct plug in to a TV and view direct from the cam.

Also, regardless of your gain, underexposure like that in the screen shot of the sd cards will look terrible. The door you mentioned is underexposed also. This cam needs light, and if you give it some, it will reward you.

Grant
 
Thank you for your reply. I will try your settings tonight. To be honest the scene files are something I have not played around with a lot yet. My old camera was a Canon XL1 and it didn't have a lot of these settings so this is a bit of a new area for me when it comes to video cameras. My Sony HC1 had a bit more image control but nothing like the range the HMC40 offers. I do have Barry's book but I just have not had a chance to sit down and really compare the different looks hooked up to a monitor.

Overall I have been pretty happy and I mainly just wanted to make sure everything was ok with my camera. I guess I was just a bit surprised because many other cameras out of the box do not show as much grain at 0 db. I have lot a lot of mixed lighting situations with my Canon XL1 and never had that type of grain in the under exposed sections when shooting 0 db. If this is normal and the way the camera works for everybody else then I guess I am cool with it. Just another new thing I have to get used to I guess.
 
Thomas,

You are switching from a SD XL-1 to a HD cam. HD creates an additional burden on the shooter. When I made the switch from a SD DVX100a to HD workflow, I had to improve everything, because HD magnifies every flaw. Better focus and better lighting are needed at the minimum. And in this case, since the camera has more image control, there is the burden of learning how to use it.

Grant
 
ggrantly said:
Thomas,

You are switching from a SD XL-1 to a HD cam. HD creates an additional burden on the shooter. When I made the switch from a SD DVX100a to HD workflow, I had to improve everything, because HD magnifies every flaw. Better focus and better lighting are needed at the minimum. And in this case, since the camera has more image control, there is the burden of learning how to use it.

Grant
Click to expand...

While I do agree with you to a certain degree I am not new to shooting HD at all. I have had my own personal Sony HC1 prior to this camera. At work we have a couple of Sony Z1U's a Sony HDCAM F900 and a RED camera which we now use for most of our shooting. We have also used a Sony EX1 and EX3 in the past.

Scene file settings are designed to give a certain look, not to clean up or fix the image. I ran through a lot of the scene settings and similar to my initial findings when I first bought the HMC40 I find other then changing the look, quality wise they are about the same. I guess I just have to accept the fact that under exposed sections of my shots are going to be a bit grainy with this camera. That is assuming that what I am seeing is normal. Of all the HD cameras I have used, seeing that type of grain or noise in darker areas at 0 DB is new. There is nothing wrong with under exposing a shot and sometimes a scene requires part of the shot to be under exposed.
 
Thomas,

In particular, your gamma, detail coring, and detail settings WILL make a large difference in noise. The scene files do much more than just "achieving a look" For more info, check out the panna white paper on AVCHD from the pro website and or look back into the Barry G postings. I assume his book on the HMC cams does this also as do the HPX-HVX book.

It would be silly to suggest that a $2000 handycam on steroids would rival a Red or other high end cams. Given enough light, the image will rival the EX1 and there have been several discussions of exactly that.

Coming from the cams you list, none of which are Pannacams, there is a different look. The Sony look, IMHO is pretty clinical and very sharp. That isn't bad. Panna has a different look, more saturated and organic, and less clinical.

Grant
 
Grant is right... the scene file settings determine not only the look & feel of your shot, but also, the amount of noise present. Gamma, detail coring, knee, master pedestal, and detail settings play a HUGE part in adding or removing "snow" from your shadows.


(To put it politely,) the stock/default settings are less than ideal, and they would be the first thing I would change when taking your HMC40 out for some shooting under ANY condition. There are many "happy scene file" settings on this board that you should experiment with. Side by side with my HVX200 bodies at work, the HMC40 with proper setup is clearly a better image in good light at 720p/24p. Alongside my friend's HPX-170 at 0db gain +NDs at the same exposure settings, the HMC40 again delivers clearly better at 1080p/24p and 30p.

Give the scene file settings a 2nd go-around with a 1080p monitor and you may find that you get cleaner shadows AND punchier, more contrasty, sharper properly exposed areas of your shots!
 
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