vivitar said

[GyRob]

that there 6000af ringflash works on the 300d and 20d I cant get it to work, anyone got one that does work ? it does fire but only at about 2% of the light ,so its hopeless.
thanks
Rob.

[kb244]

Well what mode are you shooting in, if its anything like my sunpak, the Flash is TTL capable but not E-TTL capable, which means you are stuck using Full manual mode for the flash, instead of Auto modes.

See Here : http://photography-on-the.net/forum/showthread.php?t=60938

I think its the same situation, I read the website for the Vivitar 6000AF , it says TTL capable, it maybe fully EOS Compatible, but thats mainly to say it'll partly work, but wont work via TTL ( since the Rebel uses E-TTL and the 20D uses E-TTL 2 ).

I guess what I'm asking for, is more details of how you are using the flash.

[Jim_T]

Yea.. it's the old TTL vs E-TTL

Digtal cameras meter differently than film cameras. In order to automatically evaluate the correct flash power, digicams require a pre-flash that only an E-TTL capable flash can provide.

You can use a TTL flash, but the camera has no way of determining how brigh the flash should be. This requires that you manually choose the correct exposure settings to match the ouput power of the flash. This sometimes isn't that hard if you use a flash with a thyristor.. You can correctly set the camera by way of the supplied chart.

Here's a take on TTL/E-TTL from another forum....

http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=006wyj

[GyRob]

i had set the 20d on manual -shutter 1/60 and f5.6 100asa the flash fires but its so weak, when i press the test buton the flash is fine.

[kb244]

Did you set the Flash in manual mode as well, also the shutter speed needs to be set at the camera's flash Sync Speed ( usally 1/200, but I think the 20D has it upto 1/250 ).

Like Jim_T said before, if you messed with a flash that uses a thyristor before( as I have with my older Vivitar 283, which is why i'm not too fustrated with the new one ), shouldnt be a problem to get around just gota take an extra step to correct it. What I'm begginning to see that if you are using a film-based flash on the digital, you have to set the flash in Manual mode, ( which means no automatically corrected exposure on the flash , you have to go by the guide it provides if you have one ).

On my old Vivitar 283, I have a guide wheel on the site, I turn the wheel to the ISO speed I'm using, then I look at the feet area, I See what color is highlighted for that distance of the subject, set that on the front of the flash, then on the wheel it also shows the Apeture I need to set on the camera's Full manual mode, ( Shutter speed is set to the camera's Flash Sync Speed ), and there you go, I assume the vivitar has something similar to my 283.

It might also be like my sunpak, where its a digital LCD display on the back, that shows you on a bar the covered flash range based on the apeture and ISO you punch into the back of the flash. And you can control the power of the flash in increments ( on my sunpak i can do 1/1 full power down to 1/64th power ). Since the flash is a ringlight and one of thier high end ones, I'm going to assume that 1) There is a full manual mode that can be tweaked , 2) There is a incremental setting of the power level from the flash.

Try your Camera AND your Flash in full manual mode, with the shutter set to 1/200, and setting the aperture on the camera, based on what the flash gives you for a range when you punch a aperture and iso in to there.

[GyRob]

Thanks everyone for the help with this,the anser was to block off some of the contacts on the FLASH hotshoe,there are 5 you just let the biggest one touch ,it works fine now only manuel but thats ok- so for £54 i have ringflash :) it might not be auto but as you can check the photo that is not a problem.
thanks again
Rob.

[kb244]

Yea I kept my contacts intact because it seems that even in manual or Auto + Av, the flash has a nice big AF Assistant lamp versus the camera's and works almost instantly. But good to hear you got a work around.