G6 - Still No AF Assist Support from EX Flashes?

[jpmccormac]

Based on initial previews it looks like the G6 AF Assist is no better than the one on the G5/G3. Unless the G6 allows use of the near IR AF assist of the EX flashes, the G6 is not improved for low light focusing. Correct me if I'm wrong.

[FlyingPete]

...and there probably never will be. The compact digicams all rely on green light to focus on, as there are more green pixels on a CCD than blue or red (BGRG), that is why sometime focusing on objects not reflecting much green light (red, blue and magenta all have none) can be a little difficult.

Since the AF asset is red, it will be of no use, as the camera will not ‘see’ the light at all.

Works fine with a digital SLR, as they don't use the CCD/CMOS image to focus with.

[s00pcan]

...and there probably never will be. The compact digicams all rely on green light to focus on, as there are more green pixels on a CCD than blue or red (BGRG), that is why sometime focusing on objects not reflecting much green light (red, blue and magenta all have none) can be a little difficult.

Since the AF asset is red, it will be of no use, as the camera will not ‘see’ the light at all.

Works fine with a digital SLR, as they don't use the CCD/CMOS image to focus with.

Color doesn't matter that much since they only use edge contrast to determine if it is in focus or not.

[Andy_T]

Color doesn't matter that much since they only use edge contrast to determine if it is in focus or not.

Unfortunately, it does matter, as a green sensor will not perceive an edge contrast illuminated with red light, because red light is completely filtered out by the green filter in front of the photo site.

Best regards,
Andy

[JohnR]

Finally a clear explanation on this issue. Thanks a lot.

[FlyingPete]

An interesting thing I have read about Sony camera, is that they use a red laser for focus assist, so the green thing must be Canon Specific.

I had read somewhere that you can now get green laser pointers, so I though it might be worth looking at one of those to project a pattern for focus assist, well too issues, they are incredibly bright, and have you seen the price!!!

[Deckyon]

I have used a "patterned" red laser pointer in the same way Sony uses theirs and have gotten quick, tack-sharp low-light images.

You can get green pointers, but I have yet to see one with a patern. Just the "point" of the pointer will not work. Sony's cameras use a pattern, not a point.

[FlyingPete]

I have used a "patterned" red laser pointer in the same way Sony uses theirs and have gotten quick, tack-sharp low-light images.

You can get green pointers, but I have yet to see one with a patern. Just the "point" of the pointer will not work. Sony's cameras use a pattern, not a point.

Have you shot an image of the laser and used photoshop or simular to out all the light but green? (Can you drop colour channels with a RAW importer?) Would be interesting to see if it shows up, if it doesn't perhaps the green pixel thing is not entirely true!

On the green laser thing, they should work with the red laser pattern filters too, haven't got the $$$ to find out!