flash question

thebaz

When using an external flash , is there any point upping the iso as well , or should it be set at lowest value possible ?
cheers.

DaireQuinlan

I reckon you'd be best going for the lowest ISO possible, and opening up the aperture if you need more light. I presume you're using whatever the nikon digital TTL flash is (i-ttl ?!?), if you fire off a shot the flash should complain if it had to fire at full power (and the shot is underexposed) so you know to open up a stop to get more light in. One of the benefits of using flash with film is that you can still use slow slide and rely on the flash to do the donkey work for you light-wise, Its astonishing just how much light a big nikon (or canon) strobe can put out at full power !

Borderfox

Keep the iso as low as possible but even in overcast conditons you might have to up the iso to get the proper exposure unless you have the camera set to synch at 1/250th. Practise and take a lot of shots and experiment with all the settings. If you put the camera in av and let it decide dont forget it will expose for the background also.

Borderfox

one other thing upping the ISO will increase the range of the flash burst.

Fionn

i've inadvertantly used flash with ISO 800 with quite marketable and acceptable results, but by and large i'd use maybe 150 to 200 ISO with flash - depending on the lighting conditions of course

DaireQuinlan

Borderfox wrote: »

Keep the iso as low as possible but even in overcast conditons you might have to up the iso to get the proper exposure unless you have the camera set to synch at 1/250th. Practise and take a lot of shots and experiment with all the settings. If you put the camera in av and let it decide dont forget it will expose for the background also.

Strictly speaking if you put the camera into Av then it will expose correctly for the ambient light, and the TTL flash metering will ensure that the flash won't overexpose the shot. This is useful if you want fill flash. ie you meter correctly for ambient but you want something with a considerably lower ev to also be exposed correctly, you use the flash to fill this part of the scene. If you're shooting in a flash only situation you may as well just stick the exposure onto the flash-sync speed and use the flash to light the scene. There are situations in between where the flash is the primary light, but you also want to ensure that some measure of ambient creeps in. This is where you might want to either increase the exposure time, or up the ISO, or open up the aperture a bit. This is all assuming of course you're using TTL (or whatever variant for the camera system you're shooting with) flash. With manual flash (either PC-sync, wireless, or slaved to your on-camera) the story gets more complicated still

Fionn

tis complicated

i hardly understood anything there!!

ayway
i'll be bringing to the next meet a vid dedicated to just that topic - Canon Flash 580 & 320 and what can be done with them

cheers

Fajitas!

I'd have no problem upping the ISO if I was shooting something for myself - a night out, etc - it reduces the amount of battery used per flash.


I do like grainy photos too though.

thebaz

thanks guys ,
I was shooting some outdoors halloween stuff , and i "accidently" had the iso way too high - over 1,000 - anyway from what Daire says for Halloween oudoor stuff , your probably best uppping the iso a bit , but not as high as i had , just to get some of the Halloween ambience .

On another note, i used the attached plastic diffuser, they sell the external white plastic ones for 27 euros , are they worth it ?

DaireQuinlan

thebaz wrote: »

thanks guys ,
I was shooting some outdoors halloween stuff , and i "accidently" had the iso way too high - over 1,000 - anyway from what Daire says for Halloween oudoor stuff , your probably best uppping the iso a bit , but not as high as i had , just to get some of the Halloween ambience .

On another note, i used the attached plastic diffuser, they sell the external white plastic ones for 27 euros , are they worth it ?

Elastic bands. There's your vital money saving flash accessory :-) Scrunch up a piece of A4 paper (or neatly fold it into a diffuser shape) and attach it to the head to diffuse, or curl it around and rubber band it around the top of the head to act as a bounce card. The possibilitys are limitless ! Although of course those diffusers are a lot more convenient :-)

I'll just have to name-drop the strobist here again just in case anyone is reading this thread and hasn't read any of the site. Best. Flash. Site. Ever. !

strobist.blogspot.com

ThOnda

If you increase ISO, you are getting more depth your flash is able to light. I love grain too, so Fajitas, go on!