On Nov 15, 2004, at 8:30 AM, J. C. O'Connell wrote:
TTL is fine but a lot of people do Macro with strobes (myself included), and I am not aware of any SLR cameras that can do TTL flash metering.
My technique is I use a flash meter, calculate bellows factor exposure compensation, and determine a base fstop. But even then I usually bracket unless I have used exact same lighting setup, film speed, lens and magnification, etc.
I would imagine with a DSLR its just a matter of running a few exposures and adjust fstop until you get what you want on the image review screen.
JCO
-----Original Message----- From: Rob Studdert [mailto:[EMAIL PROTECTED] Sent: Monday, November 15, 2004 8:46 AM To: [EMAIL PROTECTED] Subject: RE: A Question About Macro Lenses
On 15 Nov 2004 at 7:23, J. C. O'Connell wrote:
Unless the 125mm zoomed out to 62.5mm at 1:1, it is going to need exposure compensation.
Of course you are correct, I was simply drawing a relative comparison to
another lens.
What you have is essentially a variable aperture zoom with that lens, how do do you know what exposure compensations to use?
I don't really care but I do know now that relative to a "non-zoom" macro lens it requires about an extra half stop when approaching 1:1. I haven't used external meters for macro photography since the late 80's. Then I had a 67 and bellows and I was glad to get my hands on a TTL prism.
Does the lens barrel have exposure compensation markings on it?
No
At least with a fixed focal length and aperture you can calculate the correct compensations based on magnification or bellows extension, but with variable aperture those techniques won't work...
..or you (I) could use the TTL metering, which I do quite successfully.
Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://members.ozemail.com.au/~distudio/publications/ Pentax user since 1986, PDMLer since 1998