View Full Version : Auto ISO?


Jon Vincent
March 7th, 2011, 11:22 PM
We just got our GH2 (man, that took a lot of looking around). Basically, I love the camera. Been looking at some setup information and keep running across people who say to set it for auto ISO. I tried it, but it kept adjusting as I moved the camera and did so in steps, not a smooth transition. In addition to the constant noise as it switched it just looks terrible. I figure I must have set something wrong since people seem to swear by this setup.

Any ideas of what I did wrong?

BTW - Using a Pany/Leica 25mm 1.4 lens with the adapter.

Jeff Harper
March 8th, 2011, 08:14 AM
Thanks for posting Jon and for including your lens model in your post. Bottom line, I'm guessing it's just too dark, but to be sure you would need to do the following.

To narrow down what is causing your problem, do the following:

1. Lock your ISO at 200 or even 400, just make mental note as to where you set it.

2. Then open up the lens full wide (in the case of your lens that would be f/1.4).

3. Set your shutter speed to 60fps.

4. Shoot some video.

See how that looks. If you can't see anything in the viewfinder and if your screen is black, it's too dark and you need more light. The camera and lens cannot perform miracles in that case.

We don't know what your shooting, indoors, outdoors at night, etc, and without footage, it is impossible to know, or without a specific description of your shooting environment.

Attach a still shot taken of your video so we can see: go below the submit repy button when you are typing a response, and click on the Mangage Attachement button.

Use Windows snipping tool if you have Windows 7 to get your screen grab. By playing the clip in Windows Media Player, pausing it, then use snipping tool to cature a snapshot of the image, then you can upload here if you wish.

Jon Vincent
March 8th, 2011, 08:28 AM
Hi Jeff. Thanks so much for the reply. I guess I am not explaining my question clearly. With a locked down ISO things work just fine. In fact, I really don't mind shooting with most everything in manual mode (I am a control freak).

My question was really about using the autoISO settings, but I think I may have figured it out. So people are basically setting the auto ISO then pointing the camera to something where they feel it looks good and then shooting from there. Makes sense I suppose. I was just not liking the way the preview was looking, but then there's always a quick hop back to manual mode.

It seems there is some automatic exposure still happening even with everything set to manual. Looks like an exposure compensation 'feature' and I cannot find out how to turn it off. As I move the camera from dark to light areas I can see the compensation meter move and the picture gets lighter or darker (like AutoISO this does not happen during shooting, just preview). Any idea how I might turn this off as well?

All in all I am loving this camera. Going to be selling the Sony EX1 to add the AF100 to the mix. Maybe one more GH2 and a good set of lenses and we're golden!

Jeff Harper
March 8th, 2011, 08:59 AM
Jon, I do not yet understand how to operate the camera, let me be clear about that.

I used it for one wedding, and it was a challenge.

I've heard the suggestion to run in auto ISO, but I didn't like it. What I may try next time is set the ISO limiter to 400, or 800, or wherever I want the limit to be. THEN run it in auto iso, that way it does not max out at 3200. Then run the exposure in auto and lock down the shutter speed.

To do this you would run in Shutter Priortiy Mode, and set the shutter at 60fps. Then set the max ISO to 800, or wherever. Your ISO will run in AUTO, but will be limited to whatever value you set it at.

In the Shutter Priority Mode your exposure is automatic, but should run mostly open since you set a limit on the ISO. You should get good images, but I'm only guessing this will work.

Try it.

Jeff Harper
March 8th, 2011, 09:37 AM
Jon, getting the right combination is not going to be simple, whatever you or I come up with, because it will be different outdoors and indoors. I would not be surprised if we see an abandoning of the camera (a weeding out) by wedding videographers such as myself who cannot handle this camera for run and gun shooting.

Last week I considered giving up and going back to a traditional video camera.

Outdoors, unless you're in shade, you will need a ND filter, which has to be put on the camera for sunny conditions, which complicates things further. How will this affect settings, and what mode to shoot in then?

I don't have a clue.

ANOTHER thing...lenses like your 25mm are difficult to use. I plan on getting a 30mm 1.4, also very tough.

Experienced photographers will tell that controlling depth of field and focusing is not for the faint of heart with these lenses, and that is on a still camera. Forget video.

These are truly not run and gun cameras, and it could take up to a year of regular use to become proficient users of these cameras. The great photographers spend years learning the craft, and with the GH2 you and I have entered the realm of photography.

Using a still camera for video means we are not videographers any longer, but instead by necessity we must become photographers. And to become proficient takes time.

I spent about a year or so using a still camera, and because I used nice lenses I got some very nice photos. But 80% of my photos were garbage. That is the problem with video, nearly 100% of my footage must be good, or I'll have an unhappy customer. To achieve that goal will be difficult indeed.

Lisa Maxwell
March 8th, 2011, 11:27 AM
Jeff,

Thanks for posting this info. It is useful for my decision in buying a new DSLR for weddings.

Jeff Harper
March 8th, 2011, 11:59 AM
You're welcome Lisa. I receive my GH1 tomorrow, and I have lots to learn with it. As you may have read, my GH2 is at the factory, and I don't know when it will be returned.

Someone posted a month or so ago, an account where he was shooting with a traditional video camera, alongside two guys with DSLRs and they were shooting I think some outdoor wedding stuff, or some such thing, the details elude me right now.

Anyway, the poster stated that the DSLR guys were pretty experienced with their cameras.

Yet they missed many shots, because of the difficulty they had in focusing while minding exposure settings and such. The spontaneous shots become difficult with these cams.

What complicates this already complicated process further, is each lens used for your camera must be shot with differently. Each lens focuses differently. Depth of field performance differs, which in turn affects focusing. Do you want a large depth of field, or no? Can the lens you use work with the group shots outdoors, or are some folks going to be out of focus? Well then, you might need to change your exposure (f stop) in order to get the proper focus. But if your lighting is dim and you set the exposure to too high a number, your image will be underexposed. In that case you need to adjust your ISO. There are potentially hundreds or more combinations of settings, per lens.

By the time you've got it set up, the moment is gone and you've missed your shot.

I found the 20mm Panasonic lens was very nice, but good god, at 1.8, it was nearly impossible for me to keep things in focus. It will be worse with the 30mm 1.4 that I have been planning on.

To get the images I want, I need fast lenses, but the faster they are the harder they become to use, particularly the wider ones.

I'm not being pessimistic, I hope. I'm just like Jon, trying to make the camera work, but I also feel the magic formula for making these cams work well in a run and gun situation don't exist. I see the coming year as exciting, but extremely challenging.

Norm Rehm
March 8th, 2011, 01:22 PM
Jeff

Why did you need to send your GH2 in for repair? Is there a problem with these new cameras?

Norm

Jeff Harper
March 8th, 2011, 01:39 PM
Norm, there is no problem with the cameras, I've heard of no issues like mine. I can assure you the cameras are fine.

Patrick Janka
March 8th, 2011, 03:47 PM
Auto ISO saved my life today. I did my first gig filming real estate on a merlin. My god I had to keep stopping for every room to readjust the exposure. I'm used to always filming in fully manual mode. I vowed never to use auto ever. Well I decided to flip on iA mode and damn if the exposure was perfect in every room and outside. For real estate videography where you're on the move and the lighting keeps changing it's a must.

Jim Forrest
March 8th, 2011, 03:59 PM
Hi Jeff. Thanks so much for the reply. I guess I am not explaining my question clearly. With a locked down ISO things work just fine. In fact, I really don't mind shooting with most everything in manual mode (I am a control freak).

My question was really about using the autoISO settings, but I think I may have figured it out. So people are basically setting the auto ISO then pointing the camera to something where they feel it looks good and then shooting from there. Makes sense I suppose. I was just not liking the way the preview was looking, but then there's always a quick hop back to manual mode.

It seems there is some automatic exposure still happening even with everything set to manual. Looks like an exposure compensation 'feature' and I cannot find out how to turn it off. As I move the camera from dark to light areas I can see the compensation meter move and the picture gets lighter or darker (like AutoISO this does not happen during shooting, just preview). Any idea how I might turn this off as well?

All in all I am loving this camera. Going to be selling the Sony EX1 to add the AF100 to the mix. Maybe one more GH2 and a good set of lenses and we're golden!

Jon I think I know what you are talking about and it seems to happen when setting focus. I think the camera is opening up the exposure to see and set focus.
You may be happier just using the Creative movie mode in 24p Cinema. Everything is set to manual there as well and you get a higher bit rate, I just set it to 1/50 shutter speed and use the iris and ISO to set the exposure. Then again this may not be the question you are seeking to get an answer to.

Jim Snow
March 8th, 2011, 09:24 PM
Anything auto on a locked down camera is risky. There is a very good chance that the camera will 'hunt' anytime anything changes in the frame. Somebody walking by, a cloud in the sky - anything and the camera will change in an effort to track it. That's not a good thing. A camera can 'hunt' with auto ISO just as well as it can with auto Iris.