Noise from Mini DV Digital motor & spinning ground glass

I was informed by a friend who is a DP and is familiar the Mini 35 Digital, that the noise and vibrations from the electric motor & spinning ground glass will transfer to the onboard microphone. We have a Canon XL1s.

Has any one experienced this issue?

Any suggestions in for preserving the best audio. Boom mics, wireless mics?

[Charles Papert]

Boom yes, wireless yes.

I am hard-pressed to imagine a situation where I would be using an onboard mike for Mini35 projects, other than as a reference track. It's not really a "run-and-gun" type of setup.

I haven't experienced any interference from the motors onto the audio track of the camera using external mikes or a mixer.

Thanks Charles,

We are going to be renting the Mini 35 Digital with the Canon XL1s to inexperienced digital film makers who may not be informed or have the budget to rent DAT decks or boom/wireless mics.

[Charles Papert]

I wish you the best of success with the rentals.

What follows is strictly my opinion, and please forgive me for venting:

Any filmmaker who places the Mini35 as a priority over capturing good sound is doing themselves and their film a major disservice. If they are working on a limited budget, they should be concerning themselves with the basics before the frills. Shallow depth of field is an absolute luxury compared to capturing clean, intelligble dialogue. It's a classic mistake that inexperienced (and sometimes, amazingly, experienced) filmmakers make; not paying attention to the audio. And it can ruin the film, or require hours and hours of looping time to (somewhat) remedy.

I just came off a 9 day shoot which used the Mini35. The soundman had a boom mike, mixer and one wireless. The director told me after viewing the footage that the visuals were incredible, but the sound was overmodulated in various places, had radio interference in others and was generally a big problem. I had nothing to do with the audio myself, but I still felt sorry for the director and frustrated that this had happened. There are some great performances which will now have to be ADR'd.

A DAT deck is a "luxury" (can be a great tool, but not absolutely necessary). Boom mike, however, an absolute necessity. Wireless, a very useful tool depending on the scene. On-camera mike: recipe for failure in all but very specific circumstances.

And finally--(what a rant, sorry about all this, and I may well be preaching to the choir here): the Mini35 is a pretty serious piece of gear, and requires a strong focus puller to properly execute many of the shots that come up in standard filmmaking. Shooting at a T1.4--T2 with any lens longer than 50mm and the subject moving towards or away from camera (or the camera moving)--that can get really hairy. Having closeups go in and out of focus as an actor leans in nearly imperceptibly can be really distracting to an audience. Pretty advanced stuff for a beginning filmmaker. I am concerned in the same way as when I hear "I'm going to use a Steadicam for my film that shoots tomorrow--never used it before, but I think I can just figure it out on set". I just don't like seeing folks in over their head. That said, I'm a champion of them going for it, as long as the stakes aren't too high i.e. not wasting the time of the volunteer cast and crew by experimenting with toys.

OK, I'll stop now. Like I said, I wish you the best with the rentals. But I hope you will agree with me that anyone who thinks the on-camera mike is good enough should do a bit more research.

[Dennis Hingsberg]

I just want to add the sound is 70% of what you see. (well something like that anyway)

And, I also have people call me up to rent my mini35 rig who tell me they have a crew who've shot digital before, etc.. I always tell them although the mini35 uses a digital CCD to record it's image it's nothing at all like shooting digital. You don't have auto exposure, auto focus, zoom at your finger tips and a narrow depth of field that will help you when you dolly, steadicam or run around with your camera grabbing your shots.

I've done a few shorts now with some fast paced directors trying to break out of the standard look offered by "standard miniDV" using my mini35 rig who afterwards swore they would never use the mini35 again in complete disbelief in the amount of time, skill and operation it requires. I'm talking in particular to what Charles was saying regarding actors leaning in and out, or dollying in or out towards actors, subjects and whatever. It can not be done easily single handedly.

I don't want to make the mini35 sound like a bad thing, I will shoot not even my daughter's birthday without it - but if you're feeling lucky because you saved enough money to rent the mini35 so you can shoot your next film without the dolly, prime lense selection, lighting and other film making essentials - don't bother. Rent a DVX100 and some lighting, good sound equipment, get a good DOP and you'll go a long way with your production overall.

[Charles Papert]

Yes indeedy...DV is great because it offers a high level of production value relative to its purchase price. And it can be wielded by the fairly inexperienced up to the very experienced. Every camera in this class offers an automatic mode that makes it a point-and-shoot. Fortunately, manual modes are offered also.

I remain convinced that of all of the more sophisticated add-ons for DV out there, the Mini35 is right up at the top in terms of requiring a level of experience/sophistication to achieve the desired results. It's not magic, nor is it rocket science, but focus pulling at T1.4 is a skill that can't be understated. It's a bit like thinking that because you can click the "red-eye" button in basic photo software, you could then jump into Photoshop for the first time and fully retouch a picture.

[Dennis Hingsberg]

Perhaps a better way to put what Charles is trying to say about pulling focus in perspective is with math and numbers.

On Whites home page through this link www.whites.com/cameras/field_depth.asp you will find a depth of field calculator.

With our format being 35mm, choose let's say a 50mm lens, an aperature of f1.4 and a distance of 1 meter which is about 3.3 feet. Select calculate and observe the numbers:

54.113 m - Hyperfocal distance for this lens/aperture combination
0.983 m - Near limit of acceptable sharpness
1.018 m - Far limit of acceptable sharpness
0.035 m - Total depth of field

Remember that 1 meter is approximately 3.3 feet. You will see that if your subject is sitting in focus approximately 1 meter from the 50mm lens set at f1.4, he only has a 0.035m windows of perfect focus before it will need to be adjusted.

Let's convert that to inches: 0.035m X 3.3 = 0.11 feet X 12 = 1.4 inches! You can improve upon this a little by shooting with a higher f stop, but even with this scenario using f4 will only grow the window to 4 inches.

Now imagine a nice slow dolly towards or away from your subject, or really any scenario where the subject changes distance from the lens - you will definitely be pulling focus with your shots and if indoor definitely need to light well if shooting at f4.

Even worse is pulling focus without the Cinetech follow focus unit, if you're shooting with SLR lenses you will have to pull focus right on the lens. Did your production call for an external monitor? One trick you can do is put masking tape on the lens and with a pen or marker mark your start and end points. It still takes skill and practice to master, but it can be done.