The Panasonic TM900 Users Thread

[Jerry Amende]

"...what advantages would you expect to see following this method?"

Rather than (further) hijack this thread, I've posted my reply here: http://www.dvinfo.net/forum/what-hap...ml#post1702011

...Jerry

[Roger Shealy]

I've found the AF so good on this camera, that my attempts at "improving it" with manual focus have been unimpressive. I will use manual for static shots, especially on the occasions when the subject is off center and the AF want's to focus on the background. I haven't found the manual ring very easy to achieve a "feel" for focusing like higher end cameras I've used, and the excellent fringing assist is difficult to follow when things get moving.

Have others been able to master manual focus on this cam for difficult scenes?

[Alastair Traill]

Thanks Jerry,

I have found more examples of what can be done with Mercalli V2. It looks very promising.

[Alastair Traill]

Roger,

For me motorising the control ring was a huge step forward particularly when used with the blue focus assist.
The remote control eliminates the risk of bumping the camera and I do not have to remember which way to turn the ring.
It also makes it possible to focus remotely. I have a boom that I sometimes use to when recording birds at their nests. Under these conditions I can decide the focus point rather than leaving the camera to decide.
I often use close-up lenses and the control ring is almost essential as the depth of field is only a few millimetres. Again the the focus assist is incredibly helpful.
The next step will be to add a speed control and play with follow focus but only at close range.

[Brian Tori]

Does this camera have a built-in ND which engages when bright conditions require it? Is anyone having a problem with keeping a full sunlight day under control? I used to own a SD100 which was very similar to this cam and it had the built-in ND.

[Roger Shealy]

Brian,

No ND. You either have to use a screw on ND or stop the iris/shutter down.

[Mark Rosenzweig]

Roger,

Sorry, the TM900 does have a built-in auto ND filter (maybe more than one). This is Tom Hardwick's explanation:

"So what happens when you shoot movies? Well the camera shoots at maximum aperture and if it gets brighter more and more ND is applied. Its the same in manual or auto - you think you're shooting at f/4.5 (say) but you're not - you're shooting at whatever the maximum aperture is for the focal length you've set. That's f/1.5 at wide stopping smoothly (ramping) down to f/2.8 at full tele.

So the lens 'stops down' (using ND) to f/5.6 and only if it gets brighter still do the aperture blades start to close. You can see that scenes shot at an indicated f/8 are actually shot at f/4, bringing with it the dof that comes with f/4."

This is common in small-sensor cameras to avoid diffraction at very small apertures.

[Roger Shealy]

Mark,

You lost me there. ND is an optical device to restrict the amount of light allowed into the lens without shifting colors. What you are describing is a combination of gain, aperture, and perhaps shutter speed, which doesnt seem to qualify as ND. Usually ND filters are used to allow a wider aperture and/or slower shutter speed that otherwise possible with fast optics. Here's a good Wiki discussion on the topic: Neutral density filter - Wikipedia, the free encyclopedia

So, are you saying you understand the TM900 to employ an optical ND to the camera, or just some unexpected manipulation of shutter speed, gain, and aperture? If the latter, that doesn't seem to qualify as ND.

[Mark Rosenzweig]

Thanks, I know what an ND filter is. Yes, an optical ND filter is used. Did you understand Tom's explanation about dof (need a Wikipedia reference to that? :)) and how the ND filter works in combination with aperture blades and shutter speed? It is why dof does not change when the effective aperture changes due to simply light dimming by the *optical* ND filter.

Are you now willing to concede that your answer about the ND filter in the TM900 was not correct? There was a discussion of this already. I only care about this so that others are not misled by your incorrect response, and I appreciate your trying to get it right.

[Brian Tori]

Thanks for the responses. Mark you seemed to confirm what I was guessing. That an internal ND engages automatically to try and keep the f-stop at a somewhat open position. This confirms my memory of the SD100 which I used to own. On a day which contained full sun, the iris would read f8 or f11 for example. Whereas my DSLR would be reading f22 for the same scene.

[Roger Shealy]

Mark,

Looks like you are correct and I am wrong. The TM900 seems to employ an automatic ND of some kind. Thanks for the gracious manner in which you exposed my error.


Hopefully in this exchange we don't loose the fact that there are situations where using screw-on ND filters with the TM900 to achieve a specific look beyond what the build in ND filters deliver. Agreed?

[Mark Rosenzweig]

Agree completely. In fact in all the video I shoot in bright conditions I use a screw-on optical ND filter with the TM900.

[Mark Rosenzweig]

For this TM900 video, I used a screw-on ND filter for all scenes but the final dusk scenes.

Ducks, geese, joggers, quidditch playoff (Harry Potter game), birds, graffiti. Cold, windy and sunny.

Shot 108060p. Edited in Vegas Pro, to 108030p.

Panasonic TM900 HD Video: Fall Around the The Charles River on Vimeo

And here is a frame grab from the video:

http://i849.photobucket.com/albums/a...041/004661.jpg

[Mark Ahrens]

if you shot in 60p edited in 30p, why isn't it slow motion?

[Mark Rosenzweig]

The 60p video was converted, not slowed down, to 30p, which is exactly what Vimeo always does.