[stevewong]

Hello to all,
I see this Flash ring for Canon in BH store .I would like to know, if it can be use with Pentax camera for macro shoot .Yongnuo YN-14EX-C Macro Ring Lite for Canon Cameras YN-14EX-C
Thank you,
steve

[Not a Number]

Canon's ETTL is not compatible with Pentax P-TTL / TTL. You can use this unit on Pentax in Manual mode only.

[stevewong]

Canon's ETTL is not compatible with Pentax P-TTL / TTL. You can use this unit on Pentax in Manual mode only.

Thanks for your help .
steve

[WPRESTO]

ADVICE AND SUGGESTION VAV RING LIGHTS:

1) I think it was in my K5 instruction manual that said a Pentax ring light would work in TTL mode with "A" series lenses. I purchased one to use with my SMCA 200mm f4 macro, and NOT SO. The Pentax ringlight always fired @ full no matter what I did. Contact with Pentax/Ricoh got a reply of "Of course not, look on page XXX" somewhere or other.

2) Consequently I use an old Sunpak ringlight that has interchangeable modules, with a "standard" module attached (but you can use any module: Pentax, Nikon, Canon, etc) in manual mode. The variable power slider goes to 1/16.

WHAT I LEARNED FROM A BOOK ABOUT MACRO DECADES BACK: When you move a flash closer, the light intensity increases so you should decrease exposure (less flash power or smaller aperture). If you are using a unit-focusing macro lens (=not internal focus) the effective aperture (light transmission) declines as you focus closer so you must increase exposure (more flash power or wider aperture). If you are using a macro of about 90~105mm and the flash is at the position of the lens' filter ring (always with a ring flash), these two balance each other almost exactly over the typical macro ratios (about 1:6 to 1:1) so once you adjust the flash output, ISO and aperture manually, the exposure will be correct or nearly so over this range. HANDY!

[stevewong]

ADVICE AND SUGGESTION VAV RING LIGHTS:

1) I think it was in my K5 instruction manual that said a Pentax ring light would work in TTL mode with "A" series lenses. I purchased one to use with my SMCA 200mm f4 macro, and NOT SO. The Pentax ringlight always fired @ full no matter what I did. Contact with Pentax/Ricoh got a reply of "Of course not, look on page XXX" somewhere or other.

2) Consequently I use an old Sunpak ringlight that has interchangeable modules, with a "standard" module attached (but you can use any module: Pentax, Nikon, Canon, etc) in manual mode. The variable power slider goes to 1/16.

WHAT I LEARNED FROM A BOOK ABOUT MACRO DECADES BACK: When you move a flash closer, the light intensity increases so you should decrease exposure (less flash power or smaller aperture). If you are using a unit-focusing macro lens (=not internal focus) the effective aperture (light transmission) declines as you focus closer so you must increase exposure (more flash power or wider aperture). If you are using a macro of about 90~105mm and the flash is at the position of the lens' filter ring (always with a ring flash), these two balance each other almost exactly over the typical macro ratios (about 1:6 to 1:1) so once you adjust the flash output, ISO and aperture manually, the exposure will be correct or nearly so over this range. HANDY!

Thanks WPRESTO for your advice about Manual Macro ring flash.I have Sunpak Ring R8. I think may be a new ring flash can be better for more lights. Thanks steve