Optura exposure question
 

On my Optura 60 I've noticed that the color gets much richer when you adjust the exposure down, usually at -3. Has anybody else noticed this? It isn't a gradual change either. As you adjust the exposure the picture gets darker (of course), and then with one click more its suddenly much richer and saturated. At first I thought it was just the auto gain switching off, but I've noticed it on bright scenes as much as dark ones. Anybody know what's going on here?

My initial guess is that at around -3 EXP, you're starting to see the effect of slower shutter speeds. Initially, the camcorder might be lowering the exposure by mostly relying on the aperture, but, as the cam runs out of apertures sizes, it starts to use the shutter speed more to compensate. That would explain the more saturated colors. If that's the case, then an ND filter is a good solution.

A good test would be to put the camera in TV and AV mode and lower the exposure to see which mode gives you a similar effect.

But, I'll have to check it out myself, since now I'm curious.

yes i have noticed this, there are a few factors at work here..

first the optura over exposes by 1 or 2 stops

the optura lcd is overly bright and exposes by 1 stop, turing off lcd backlight and turing down lcd brightness a bit helps, best way to do this is hook up the optura to a tv in a very bright room and try match it up

the optura lcd also has very limited viewing angle, so if its a degree off your video will looked washed out and not as rich

my rule of thumb has been underexpose daytime outside shots by one or two stops in TV mode so i can control the shutter and not get any shutter drag in my shots

I don't know if I could attribute this to the shutter speed. I've noticed it in aperature priority, shutter priority, and regular auto modes. Also, I've noticed it's less likely to want to overexpose in aperature priority mode.

Yes, this occurs in TV mode (shutter priority). I notice it around -2 on my Xi.

Optura 60 losing focus?
 

I've suspected for a while that I was having focusing issues with my Optura 60, and during a shoot yesterday a friend of mine brought along his laptop with DV Rack (awesome program!) and it confirmed it. There was plenty of light in there, so the auto focus shouldn't have had trouble locking on, but it seemed to. It would look fine on the LCD, but on his monitor you could see that it was a little soft. I'm talking about a fairly small difference. It probably wouldn't be noticeable on a regular television. Also, in the past I've generally focused by zooming in and letting the autofocus lock, and putting it into manual mode before zooming out. Again, judging by the image on the screen of his laptop, the image would seem to lose focus when I zoomed out.

I'm using the WD-58 with two step-up rings. Could that be the problem? I have a one-step ring on order (for the months now), but I'm starting to wonder if I shouldn't just get Canon's 34mm adapter lens. There isn't some kind of sensor outside the lens that is getting blocked by that big ol' lens, is there?

Another possible clue -- I was using auto mode with the exposure dropped to about -7 on many of these shots. Could that have made difference? Maybe I was starving the camcorder for light after all.

I don't think there's anything wrong with your camera.

The object you focused on, should look a little softer after you've zoomed out, because in effect, you've created a lower resolution image of that object. When zoomed in, you're using a majority of the pixels in your camera and the result is a higher resolution image of that object.

You mentioned that it was not normally noticeable until you used a higher resolution monitor, that's why I think this is a natural effect and not a malfunction of your camcorder.

Just one tip, when I use autofocus, I make sure that the lens is NOT SET to full wide or full telephoto. This gives the autofocus a little bit of play in terms of moving the lens, and in my past experience gets rid of many autofocus issues.

This is an old habit of mine that comes from way back, and it may be a mute point with newer technology, but it's something I do because it's worked before.

I realize it looks softer when you zoom out, but it was clear after doing the "zoom in, focus, zoom out" routine, that it was still possible to focus the image somewhat sharper using the monitor (at the wider setting). There have been instances where I've gotten the footage home and looked at it on our production monitor and it was unuseably soft. Other times its razor sharp. I don't get it. The manual mentions that the autofocus can struggle when there's no vertical lines, so maybe that has something to do with it. It doesn't seem to be hunting though. Sometimes it locks on, and it's just not very sharp. Anybody know where I can download a focusing chart? That seems like the place to start. I'll try not going to full wide as well. As I recall, that often did seem to be when I was getting focusing issues.

Yes, the passive autofocus system of the Opturas isn't 100% accurate. It will do the best it can and make a best guess, but it's still not going be as accurate as manually focusing. Especially, when the object doesn't have strong high contrast vertical lines.

But here are some tips to make a passive autofocus system more accurate

• For video, the best way to handle situations without any strong vertical lines, is to just create them. Print or draw black parallel lines onto a sheet of paper and place it next to the object to pre-focus. Or find something close by that will let the autofocus get a good lock
  
  **fyi do this with a flash light, to achieve critical pre-focus in low light situations.
  
  
• Also, if you only have horizontal lines in your shot, you can turn the camera sideways and get your focus lock that way. Then return the camera to it's normal position. Admittedly, this works much better with a digital still camera, and isn't that great of a technique for camcorders.

The nice thing about these techniques is they are low budget and allow you to avoid using expensive and heavy monitoring systems for focus.

And thanks for bringing it up, because I forgot about these techniques, and it's something I really want to test on an HDV system where achieving focus is more critical and more expensive.

And this is for anyone wondering how a passive autofocus system works.

Excellent Michael. Thanks.

Optura 60 Screen... A Lens Problem???
 

Hi everyone. Im new here and new to the Canon MiniDv world. I just bought my Canon Optura a week ago at Fry's for US$599.90 and currently exploring all the functionalities of it. I love it and low light is tolerable and not as bad as it looked based on the reviews though i can say its a not as good as others who are really good in lowlight but then how often do we shoot in lowlight anyway?

anyway, i'm nearing its 15 days to return if it has a problem coz i did not buy the extended warranty and i noticed somethin on the screen when shooting in lowlight and focusing it on a white wall. it seems the lcd screen is divided in the middle (exactly in the middle of the lcd screen and also in the viewfinder) with the left side having a greenish color and the right side of the lcd screen has somewhat a better color. at first i thought it maybe just the lcd screen effect but when i looked at the viewfinder i can see the same thing and when i connected it on TV the display looked the same. Could this be a lens problem? I tried test recording a video on lowlight and focused on a white wall and on play i noticed the same oddity. On bright lights though there seems nothing of this issue can be seen. its very crisp and bright and the video looks great.

Shall i be concerned with this? Shall i replaced it with another one? or is this just normal effect when it is in lowlight? Do you guys here have exprienced this? I wanna have a peace of mind on this. i need your advice here please.

Thanks.

The camcorder should not be behaving that way. I'd get it replaced asap, and see if the 2nd one has the same problem.

Hope the problem gets fixed, and welcome to DV Info!

I had almost the exact same problem with mine. Return it!

Thank you for your replies. I appreciate it. I went to Fry's this afternoon just to check out the camcorders on display and to see if i can recreate the problem not just on Canon camcorders but on the other camcorders as well. I have had problems recreating a dimmer light since its quite bright inside. But then I did not see that oddity on other camcorders but when i tried the Optura 50 I almost had the same issue as on mine. I'm wondering probably its just how it behaves. I showed it to my brother but he's had a hard time seeing what i'm seeing or maybe im just being paranoid about it. I'm going to return my camcorder tomorrow and ask for another one and see if its better. I'm crossing my fingers.

Thanks again guys.