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-   Sony NEX-VG10 / VG20 / VG30 / VG900 (https://www.dvinfo.net/forum/sony-nex-vg10-vg20-vg30-vg900/)
-   -   Why no Focus Assist? (https://www.dvinfo.net/forum/sony-nex-vg10-vg20-vg30-vg900/490070-why-no-focus-assist.html)

Henry Williams January 22nd, 2011 09:22 PM

I only ever focus manually, so don't jump yet ;) The lack of focus assist is an issue and I'm going to be buying a small monitor as soon as funds allow (prob. either a 7inch Lilliput or the new sony SLR one). At the moment I'm gauging it by eye. With my current interview setup I'm running two cameras side by side, the SONY getting a CU and my XH-A1 on a Medium Shot, both to give me more options in the edit and because I'm running audio through my XH-A1 anyway so it might as well be filming something! It does safeguard me somewhat against the problem you described.

At the moment I'm using the kit 18-200 lens and the 16mm pancake e-mount.

It's also only fair for me to say that I'm not operating at the same level as you and as such my demands in camera terms are probably less stringent. Most of what I shoot is low level corporates and music videos that only ever wind up online.

Henry Williams January 22nd, 2011 09:31 PM

Many thanks for your detailed reply, Steve. Sorry to ask you for clarification on one point... Does the NEX-5 allow you to directly press a button that alters the shutter speed whilst in video mode or do you have to do it indirectly by altering the amount of light in the shot?

Steve Mullen January 22nd, 2011 09:47 PM

With the vg10 you can set anything by it's own button. But, if you are in normal daylight, after setting what you want, you will then need to use the correct ND filter to get the exposure correct.

Bottom line, because none of the products have a built in ND filters, you always need to add your own to control light. If indoors, you likely won't need ND filters because you can control light directly.

For you, it makes most sense to set the aperture to get a shallow DOF. Then add a ND filter that brings the shutter speed into the range of 1/50 to 1/125th because you don't have much motion in you shots. You can use this workflow with the VG or the NEX.

You can also use the PROGRAM mode on the VG which tries to keep the shutter speed at 1/125th.

Henry Williams January 23rd, 2011 06:35 AM

Steve, many thanks for your reply, but I own a VG10 and know how to use it properly.

What I'm asking is specifically whether the NEX-5 has the facility to directly manually control the shutter speed?

EDIT: I'm not meaning to be pedantic, and apologise if my repeated question comes across as such. The only reason I'm asking is that I get requests for camera advice from people through my youtube channel on occasion. I normally provide what information I can about the cameras I have first hand knowledge of and refer them on to forums such as dvinfo for further information and for advice on cameras which might suit their needs but which I don't have direct experience with. I wouldn't feel comfortable suggesting the NEX-5 as a possible alternative to someone considering buying a VG10 or GH2 unless it had the facility for direct manual control over all the settings one would normally expect in a decent camcorder. Whilst I understand from your earlier very informative posts that the NEX-5 offers full manual control over gain/iso, white balance and focus I am still a little unclear as to whether it has a button that directly controls the shutter speed.

Many thanks for your time,

Henry

Steve Mullen January 23rd, 2011 11:40 PM

I understand what you want -- a simple YES or NO.

While you may own a VG10, if you think that knowing the answer to your question will enable you to give useful advice to others, you are missing something important about BIG CHIP cameras: you first set DOF by setting the aperture. Once set, YOU do not set shutter speed. Given the amount of light there is only one possible shutter speed -- and the camera has already set it. In other words, the shutter speed button isn't used. You are, like I did for weeks, moving your camcorder thinking to the VG10. (You also set the aperture first in order to prevent diffraction. There is a very narrow range of apertures that you should use.)

Putting NEX electronics in a camcorder shape, does not make the VG10 a camcorder like other AVCHD/HDV prosumer camcorders. The NEX and the GH2 are EVILs designed for shooting electronic cinema by those who simply can't afford film.

PS: Sony consumer camcorders often do NOT let you set shutter-speed because they want you to set the aperture so they can automatically insert the correct ND filter. Then, they set the shutter speed.

Henry Williams January 24th, 2011 03:08 AM

Many thanks, Steve.

Steve Mullen January 25th, 2011 05:10 AM

Here's more.

You set shutter speed at 1/50th like you do with a camcorder. You set the camera for the interview 6 feet away. You zoom in at 35mm to frame an interview.

You set the exposure at f/4.5. What could go wrong when two people sit down?

With a camcorder -- nothing. All you have set is the exposure.

With the VG10 -- you are in deep trouble. Why?

Because the TOTAL DOF is 6 INCHES!

Try keeping two faces in focus as they gesture and lean forward and backward.

That's why you start with DOF, then set aperture. It turns out because there is very little motion in the scene -- the shutter speed doesn't much matter as long as it doesn't fall below 1/40th second.

End of lecture.

Henry Williams January 25th, 2011 06:50 AM

Many thanks Steve, but I guess this message highlights the difficulty I'm having with the idea of effectively running the shutter speed on auto. In a shot with lots of action - say filming a sporting event - I might want to have a shutter speed of anything up to 100/1 or 150/1 in order to accurately capture fast motion, or maybe I have a short film where I want to achieve a Saving Private Ryan look. Maybe I'm shooting a music video and want the shutter speed to only use multiples of the frame rate to make sure I have a filmic feel to my footage, or maybe I just want to maintain my shutter speed for consistency when I cut between different angles.

Of course Aperture is very important with these cameras, much more so than a camcorder with deep DoF and I'm very grateful to you for your comments and advice; as you mentioned in your first post on this topic it's a case of adding light to the scene/using an ND filter/applying gain until you can use the aperture and shutter speed you want. But in less than ideal scenarios, when something has to give, I want to be able to tell the camera which thing it needs to be, not the other way around.

I completely understand that you may feel I'm using the VG10 incorrectly or am speaking from inexperience (and If I reread this post in a few years time I'm painfully aware that I'll probably agree with you!)

Henry

Steve Mullen January 25th, 2011 08:46 PM

I think I see the word that is causing the problem, AUTO. Let's use the term APERTURE PRIORITY.

Note that the word priority only means we set the aperture (DOF ON A BIG CHIP CAMERA) FIRST.

It means the first creative choice is DOF. An option you never had with camcorders before. So in the sports example, you would likely decide you need a deep DOF so the aperture would be set small (f/16). With music video example, you would likely choose a shallow DOF so the aperture would be large (f/6).

Once you make that creative choice (setting) given the amount of illumination, the camera makes a reciprocal suggestion, the shutter speed. This is speed it calculates is needed for the correct exposure.

What if you had set the shutter speed in SHUTTER PRIORITY? it would have calculated an aperture value to achieve the same exposure. You get the same exposure either way. And, the value it chooses is not going to very far from correct. If you want it lighter or darker, you adjust it with the Exposure Compendation dial.

Thus, you either have the camera choose the shutter speed or the aperture. I would argue that the only reason to buy a clumsy camcorder is to have creative control over DOF. But, let's say that you ALSO want control over the shutter speed. Which you must have because you are shooting at 25fps.

First, unlike a 50i camcorder, you would never ever set the VG10 -- when there is fast motion, to anything faster than 1/80th. Second, to get a film look you would set it to 1/50th. Third, when there is little motion you can go up to 1/125th. So the choices you have been making aren't the best because you are still thinking you are using a camcorder and not a film camera.

So, no matter which initial creative choice you make, the camera has given you a SUGGESTION as to the second choice. You are free to look at its choice and say no. But, the only way you can actually make a change AND KEEP EXPOSURE CORRECT is to add or subtract light and/or gain.

Now we come to the magic word MANUAL. Can't you just dial in the other value you want? Yes you can with the VG10 set a dial to anything you want. But, there is one, and only one, value that can be used and still deliver the EXPOSURE you want given you have already made the first choice.

Therefore, when you want to alter the cameras suggestion, you can't do it by directly making a change to the other setting. You need to control light and gain, just as a filmmaker controls light and chooses film speed. You alter these until you get the shutter speed (or aperture) to the value you want.

Outdoor sports will require an ND filter because if you choose a deep DOF you've set the aperture to f/16 and the shutter speed will likely still be too fast. You choose the ND based on how far the camera's suggested value is from the range of 1/40 to 1/80. For your music video where you set the aperture to f/6, you will control lighting to get the shutter speed as close as you can to 1/50th.

This is a PITA, which is why it only makes sense to go through all of this if you want to work like a filmmaker to get both 25fps and control over DOF. Unless, you want the latter, there's no real reason to buy a big chip camera because most any camcorder can provide 25fps.

And, if you agree you want to set DOF first, then for the most part, you use a NEX just like a VG10. The number of buttons you have or don't have, doesn't make much difference since the creative decisions are the same. That's because photography requires you to have the understanding of the reciprocal nature of motion blur (shutter speed) and DOF (f-stop) be second nature.

Tom Hardwick January 26th, 2011 02:23 AM

Steve: Excellent!

Henry Williams January 26th, 2011 03:13 AM

Many thanks Steve, for taking the considerable amount of time required to explain to these slowly whirring cogs. Think I'm starting to understand what you're saying but will need to spend a few days figuring it out.

Steve Mullen January 26th, 2011 04:57 AM

You have no idea how much you have helped clarify my thoughts for my book.Many of the things, perhaps most, I am only now able to put into words. I've been rewriting the Shooingt Guide each time we have an exchange.

Some months ago I started to realize how complicated this all was. It's been decades since I had to deal with a fully manual camera.But, maybe not dealing with buttons to bring-up menus was actually easier.

Last night I read this preview of a retro digital camera that shoots 720p24. I invite everyone to read this.

Fujifilm FinePix X100 First Look Preview: 1. Introduction: Digital Photography Review

and

http://www.youtube.com/watch?v=r1fT5...layer_embedded

But, could one shoot today only with a 35mm fixed lens? If it had a 2X and 3X tele-converter, it might be a winner for some.

Henry Williams January 26th, 2011 02:29 PM

I'm very glad it was useful to you. It's certainly been of enormous help to me - I'm self trained so I rarely consciously think about what I actually do to get a decent picture- it's just the result of knowledge built up by a lot of trial and error over the years and a lot of help from people on forums such as yourself- having read through what you've written with my camera infront of me I absolutely agree with your post.

With my old main cam, an XH-A1, I'd almost always shoot with the aperture as wide open as possible in an attempt to get decent shallow DoF (or right at the telephoto end of its range for the same reason) but had the luxury not only of a couple of stops of ND built into the cam but also the ability to use minus AND positive gain and so could afford to be a little more insistent about shutter speed as I had two other settings to juggle to get the correct exposure in addition to adding lights/reflectors etc...

Obviously the VG10 is a slightly different kettle of fish. I'm still adjusting to the idea of not only being able to dial down the iris and still have shallow DoF, but it actually being desirable to do so in a lot more situations and the knock on effect that this has on my options for the other settings. I'm really missing my ND and minus gain at the moment! So I think a variable ND filter is getting added to the long list of purchases, which should allow me a little more room to maneuver...

Having come from a cam where you almost never had to go into the menu system whilst shooting (everything was taken care of by three lovely big wheels and some customisable switches) I definitely think changing to the VG10 is a bit of a learning curve, but I'm sure by the time I've shot a few hundred hours with this cam I'll have it down to a fine art ;)

Charlie Webster January 28th, 2011 02:28 AM

Great discussion

What may or may not be clear:

VG10 you can adjust shutter while recording directly with the wheel.

Nex-5 you cannot.

That said, all the nex-5 video I've shot comes out smooth--but I have not shot much with the slow kit in super low light.

F/2 seems fast enough with nearly any lens to keep the noise under control in typical event low light--though if it's really dark you can go faster.

Both cameras manual focus as well or better than a DSLR mirror--without magnification IMHO. Yes focus assist would be nice in video, but I would seldom bother to use it.

For whatever reason the VG10 does seem a bit better in low light and to keep steady with Non-AF lenses than the Nex-5.

Most useful primes are 20-36mm, which can be handheld, though not forever. 24 is a real sweet spot--so a fast 24 is very usefull. I use a nFD 24 f/2, which is way sharper than needed for video.

Any 20mm f/2.8 is great, but the really fast sigma would be the best for video (but not for stills).

TY for all the great theory above.

Steve Mullen January 28th, 2011 04:34 AM

"VG10 you can adjust shutter while recording directly with the wheel."

Which, if you are used to a standard camcorder with a rotary switch or a menu item -- this can be a shock. If you feel for the Dial to find "home" so you can then move a finger to one of the other buttons, it's VERY easy to change the shutter speed.

The other GUI bug is that in Video Mode you can't use DMF. Yet the FOCUS button sends you to the Dial where you make the AF or MF choice after which your press the Dial.

Since you only have TWO choices in Video Mode, the FOCUS button should toggle between MF and AF.

Sony's lucky Canon hasn't hasn't put the 60D guts into a camcorder package.


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