Continuous shooting with fast shutter speed.

port 21

3

« on: 25 / January / 2009, 13:59:42 »

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Hey,

I have been a "lurker" on the forum for a while, until now all my previous questions had been asked, so i didnt feel it necesary to sign up.

But ive encountered a problem

Im using the latest stable release for the powershot A550.

My EOS has died (occupational hazard i suppose, it was dropped from the top of a half-pipe, my passion is extreme sports photography). So my back up camera, my powershot has come out.

I would very much like to be able to get fast frame rate continuous shoot on eit, but im having some major troubles doing this, the shutter speed setting doesnt seem to affect the image at all, and i dont think an option exists to inscrease the amount of images, although i may be wrong.

I want to capture about 2 pictures every second, if possible. If not then anything will do.

My main issue is the shutter speed, it seems to decide when it wants to work, i got perhaps 2 decent images (of a zippo lighter striking, which look spretty awesome) but about 70 which are useless. Whats the secret to it?
A continuous shoot solution would be much appreciated as well.

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Microfunguy

4037

Re: Continuous shooting with fast shutter speed.

« Reply #1 on: 25 / January / 2009, 15:19:37 »

Quote from: port 21 on 25 / January / 2009, 13:59:42

the shutter speed setting doesnt seem to affect the image at all

What shutter speed have you set, how have you set it ?

Quote

i dont think an option exists to inscrease the amount of images

Just keep the button pressed ?

Quote

I want to capture about 2 pictures every second

The A550 will do 1.7 shots/second maximum.

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port 21

3

Re: Continuous shooting with fast shutter speed.

« Reply #2 on: 25 / January / 2009, 16:07:15 »

I have played about a little, and managed to get it to work nicely at 1/100,000.
But as you know, i need a strong light source. Is there any way of getting the final image lighter without compromising on shutter speed?
Ive been modifying the ISO settings. But anything else which could help would be appreciated.

"Just keep the button pressed ?"

Haha, yeah, i meant is there an option which enables more images p/s. Although after a lot of looking, it appears not.

« Last Edit: 25 / January / 2009, 16:10:04 by port 21 »

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reyalp

14117

Re: Continuous shooting with fast shutter speed.

« Reply #3 on: 25 / January / 2009, 17:49:27 »

Use a lower shutter speed, a wider aperture, or a brighter light.

You could easily write script that took multiple images from a single press.

I'd question whether you are actually getting 1/100,000 and also whether you are taking pictures of any subject which requires such high exposure. If your "extreme sports" include catching bullets in mid flight, maybe so, but for normal sports photography, 1/2000th should be totally fine.

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Don't forget what the H stands for.

barret

125
S3 & a550

Re: Continuous shooting with fast shutter speed.

« Reply #4 on: 26 / January / 2009, 03:50:11 »

Quote

is there an option which enables more images p/s.

well, the limit is your camera, so if max. for your cam is 2.3 fps, then you can't go faster, even with CHDK.
but, you can use rapid intervalometer script, which simulates 'button-pressed-and-hold' action. using this, you can take pictures as fast as possible in burst mode. in this scipt you can set the time for how long button is "pressed".

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my timelapses on Vimeo my startrails gallery

Microfunguy

4037

Re: Continuous shooting with fast shutter speed.

« Reply #5 on: 26 / January / 2009, 04:40:00 »

Quote from: reyalp on 25 / January / 2009, 17:49:27

I'd question whether you are actually getting 1/100,000

I am quite sure you are not.

I am thinking of removing such high speeds from SDM, I do not believe they are real.

This needs to be tested without using flash.

I have seen the test using a laser, I am not convinced.

A 'big deal' is made of this CHDK feature, I do not think it is justified.

David

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Ailurus fulgens

38

Re: Continuous shooting with fast shutter speed.

« Reply #6 on: 26 / January / 2009, 04:55:29 »

actually you can test this using flash, since flash duration is longer than 1/100.000. for example with the same flash and the same setting, i experience darker pictures the more i increase the shutter.

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barret

125
S3 & a550

Re: Continuous shooting with fast shutter speed.

« Reply #7 on: 26 / January / 2009, 05:08:01 »

for me, "rotating drill" is a convincing method of measuring shutter speed, as far as we know exact rotation speed of the drill.
anyway, as far as i know max. shutter speed is around 1/20 000 or 1/40 000 rather than 1/100 000 (at least for canon s3).

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my timelapses on Vimeo my startrails gallery

whoever

280
IXUS950

Re: Continuous shooting with fast shutter speed.

« Reply #8 on: 26 / January / 2009, 05:33:37 »

Funny to see a reincarnation of this old story... With the drill and alike you determine the flash rather than shutter duration.

I made some tests early on, with the results -- obviously valid only for my camera -- as follows. I could increase real shutter speed to ~1/5000, i.e. ~3 times over the Canon's 1/1600. Increasing (overriding) the speed further, the exposure follows more or less accordingly, but the actual duration of the capture remains unchanged at ~2ms. Overriding too much, it appears that the exposure doesn't follow linearly any more, plus there sometimes appear artifacts such as non-uniform brightness across the image. Thus, I would say the super-duper overrides are sort of real, in the sense that in any case the exposure decreases, which can be used to advantage in some cases, e.g. shooting close-ups with flash.

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port 21

3

Re: Continuous shooting with fast shutter speed.

« Reply #9 on: 26 / January / 2009, 17:25:52 »

Thanks for all the replies guys.

Im off to the skatepark on monday, so i'll try everything out.
Ive made a magnetic lens fixture so i can get my fish eye and filters from my eos on there.

It also seems that i can only recieve fast shutter speed when i have flash enabled. I was wondering why this is?

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