Frame Accumulation Help please

[Michael Knight]

Need advice on how to use Frame Accumulation with the F350 please.

I tried SLS mode and something like 8fps for a moonlight effort at getting footage of a snow-covered volcano but it didn't do anything for me.

Likewise my effort at enhancing a starry night ....

So obviously I am not clear on how to set this up.

I suspect I have my head on back to front here...should I have gone for the 32 or 64 fps instead of the low numbers?

Having seen Mark Falstad's Iditarod shots - dogs coming into camp with tongues lolling and the only available light being from car headlights, ..well, there's nothing wrong with trying to emulate the masters is there?

But despite some extensive Google searching for "how to use frame accumulation"...no good explanation so far about what it does or how it does it.

Michael Knight

[Jonathan Ames]

E-mail Paolo on this . What he's done with El Papels scenes is incre3dible and we're getting ready for a night time shoot out with frame accumuklation and SLS on Tuesday. BTW, the offer still stamnds if you want to come down for the Tuesday shoot!

phciccone@gmail.com

[Michael Knight]

Thanks Jonathan.

I'd love to visit, but the docko has our full attention until we get it out - hopefully by the end of February.

So far it has been all "outgoing" and no "incoming," which is okay in a war zone but in this business it really stretches the budget:-)

However I have no doubt things will turn around admirably since our advance research indicates a genuine demand for the subject matter - world-wide - and that's without any need to approach the traditional outlets such as TV and the Big Screen people.

Nevertheless, it's early days yet, so I won't be tooting the horn too loudly until we have it in the can and then the results can speak for themselves.

Bottom line - it's a wonderful camera and a wonderful adventure:-)

Michael Knight

[Matthew Ernest Adams]

Not sure what you're looking for, but the higher the number of frames, naturally, the more light will be come apparent in your shot. Keep it steady and no moving object within the frame, unless your looking for exaggerated motion blur.

[Michael Knight]

Thanks Matthew.

Seems I got one thing right - I was misunderstanding how frame accumulation works...and probably double-confused myself because I was trying to understand it from the perspective of time-lapse with the F350 (which I have used successfully) and ALSO from my photo-journo days with a 35mm Nikon still camera.

With a still camera, as you are probably well aware but please bear with me, a slow shutter only affects a single frame of film.....

With video, it's a completely different situation, right?

So let's see if I'm any closer to the mark now that you have helped me out a little:-)

If I dial in SLS (Slow Shutter) and set it at say 1/30th, then dial in 60 frames (for example), the following will happen when I record:

The shutter will be open for 1/30th of a second.

In that 1/30th of a second, 60 frames will be exposed to whatever light is available.

If I record for let's say 100 seconds, I will have exposed/recorded 6000 frames of video.

THEN when these are replayed at standard speed, those 6000 frames will run through in 100 seconds, and the image they contain will look 10 times brighter than what I saw through the VF.

And that's because there is a "cumulative" effect going on (hence the word "accumulation") during recording....which means in other words that they have "accumulated" a lot of light (image) and this is in effect "condensed" on replay.

Am I close?

Thanks again.

Michael Knight.

PS - as for motion blur...once I get the hang of this, I can see it being useful to do a bit of blur on things like falling water (again, something I saw in the Sony F350 demos at NAB...very nice effect too).

But first things first....let me get clear on "frame accumulation" :-)

[Matthew Ernest Adams]

You got the shutter part, but the frame accumulation actually takes place in the within the camera and you'll see the result immediately in your viewfinder.

Say you're using the 60 frame accumulation (shooting 60i or 30p), the image will not change for two seconds as it is using the light value from all 60 frames on one single frame. Essentially, you only want to accumulate enough frames to make the picture viewable and not too dark, so if five frame accumulation gives you a properly exposed image use just five frames. If you push it up higher than needed, you'll get more motion blur and IMHO a less fluid shot.

When used in combination with time lapse, frame accumulation becomes a great tool for night time lapses.

[Michael Knight]

The picture is getting clearer:-)

(Did you know the human brain actually thinks in pictures? Words are just a way of evoking them. For example, say "sun" in English, and a person who speaks English will picture the sun. Say it in Chinese and a Chinese person will picture the sun. Different words...same picture).

And then we have the habit of trying to fit new information into what we already think we know...Anyway, I am now mentally picturing what you have just posted, and discarding my own corrupt mental files:-)

SO....your little tutorial has given me a much better insight into what's going on and as I picture it now, it's more like being able to go way beyond what the iris is normally capable of...so the camera is accumulating light in just one spot (frame) for an extended period of time.

I did not realize that it should show up in the VF after a couple of seconds, so this coming week I'll get outside in the dark and do some practice.

Your info is sincerely appreciated.

Have a great 2007:-)

Michael Knight.