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JimK Dec 17, 2003 9:29 PM

How to improve PDRM700 flash performance
After being frustrated for a long time about the poor flash performance of the M700 I found a way to get brighter flash pictures. First, a little background.
Automatic flashes such as the one in the M700 work by measuring the light hitting the subject and shutting off the flash when enough light has reached the subject. Think of the sensor like a bucket with a line drawn in it. Light from the sensor pours into the bucket and when it reaches the line, the flash is shut off. Of course, all this happens in milliseconds.
To get more light on a subject you can either "draw a new line higher up in the bucket" or you can cut down the amount of light coming in so it takes a little longer for the bucket to fill. Drawing a new line higher up in the bucket would require a firmware change. But, you can easily cut down the amount of light hitting the sensor so the flash stays on a little longer. Just take a piece of black electrician's tape and cover about half of the hole in the flash sensor. I've experimented with different kinds of tape and black seems to work best - apparently the sensor must "see" black. Try some flash pictures with and without the tape - you should find that those taken with the tape are brighter than those without. Of course, you're still not going to light the inside of a cathedral but, within the advertised range of the flash, your pics will be much brighter. You may want to experiment with just how much of the sensor you want to cover.
Once I settled on the size, I cut out a round piece of tape using an adjustable leather punch so it fits nicely in the slight recess of the flash sensor.
Try it, and if it works for you, I ask one favor - send EMail to Toshiba's tech support asking them to implement a firmware change to do this the right way.

Lamouma Dec 19, 2003 8:47 PM

It work's very nicely.

I have made some test.

In my basement with very dim light, I took a picture at 400 iso, f 2.8, stutter speed 1/2 sec. No Tape Instal on the sensor.

The picture came out good but it could be a little bit more lighted.

In my basement with very dim light, I took an other pictutre at 100 iso, f 4.0, shutter speed at 1/500 sec. Sensor fully covered with tape.

The picture came out very good and the lightning was a little bit more clear (more light) then the previous picture.

At the same settings as the first picture, but with the sensor fully covered with the tape, the picture came out washed out. Too much light or over saturated with light.

So I have to agree YOU are RIGHT. the sensor covering can improve greatly the FLASH performance.

Thank's JimK

michael p Dec 22, 2003 3:37 AM

Re: How to improve PDRM700 flash performance

much better flash performance.
I used electrical black vinyl tape.


Lamouma Dec 26, 2003 9:12 AM

Flash Performance
For Chrismas, I took a lot of pictures and as you can imagine almost always indoor.

What I notice is according to JimK explanation on how the Flash work, the return of the light depend on the room walls and ceiling.

What I want to say is in low ceiling condition (6 to 7 feet) the light come back to the flash sensor more rapidely and the result is picture are dark and under exposed.

If the ceiling is high (8 feet or more) the light return is longer and more weak, the result is picture well lighted and good exposure.

An other thing that I notice is by using the manual mode you put the shutter in 1/60 sec speed. The Flash work better at that speed.

At 1/60 sec. speed I was able to take picture inside at ISO 100 and at aperture f 4.0. The picture came out very good.

Have an nice Holliday Seasons.


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