So for Christmas

[as-i-said]

the wife bought me a 2* converter, (sigma) canon fit.
(not my idea)
so I put it on the camera with my 300f4, so no autofocus then, not the end of the world, but taking some pics of the full moon, they are yellow.
problem with the converter or is that to be expected.

 

[andrewc]

what is the moon made from?

what colour is cheese?

White balance issue?

 

[as-i-said]

its white without the converter

 

[Blapto]

At f/8 it's possible that there isn't enough light hitting the sensor for it to guess the white balance correctly pre-exposure.

With a grey card and a lightsource with a known temperature (such as a good quality strobe or flash) you should be able to work out whether or not the teleconverter is actually tinting the image.

 

[as-i-said]

ah a helpful answer, thanks blapto, I have taken a few shots with it on in quite good light, they are also tinted?

 

[33L]

I take it the 300 is a canon lens. From what i have heard in the past its not wise to mix manufacturers when it involves TC's. Someone may prove me weng its just what i heard.

 

[Canon Bob]

This occurs with both the 1.4x and 2x Sigma's on Canon's L's.

I've raised the issue several times in the past (eg http://www.talkphotography.co.uk/forums/showthread.php?t=63123 )

I think that it's due to interaction between the coatings used. Kenko's don't suffer the same problem.

Bob

 

[Choccy]

This occurs with both the 1.4x and 2x Sigma's on Canon's L's.

I've raised the issue several times in the past (eg http://www.talkphotography.co.uk/forums/showthread.php?t=63123 )

I think that it's due to interaction between the coatings used. Kenko's don't suffer the same problem.

Bob

This is very good to know and should go into a sticky really.

Choccy...