Hi
Hi, i currently have a gh1, and just got a nex5, i would like to do some controlled tests with different lens combos, any hints?
document what you do to the
nth degree. Use manual so that you do not get micro aperture or shutter changes (like 10th of a stop or so) which can effect your exposure comparisons. Set ISO manually.
Write your comparisons, publish them and see what comments you get. Use this in a feedback loop to assist your strategy and guide what you do in the next round of testing.
learning by doing
please publish here, perhaps with a link to a blog, these are often free and also provide image hosting and you retain control over the materials. This will also make the pages easier to load. I for one will be interested to see what you've done.
try to avoid posting 16 images into a page and say "see what I mean" without making it clear.
for instance:
http://cjeastwd.blogspot.com/2009/08/tale-of-two-teles.html
is what I consider to be a basic look at two lenses. It of course lacks statistical validity (only one sample of each lens), but I'm willing to accept that the tolerances of manufacture are close enough to make each a reasonably representative sample of each lens.
test with something in mind, with some plan.
I agree that testing for same angle of view is desireable, but is problematic because of the differing formats. I tend towards preferring the 3:2 format to the 4:3 ... but then that's how I like to compose. Clearly this makes direct comparisons problematic.
my expectation is you'll find that both cameras are so close in performance as to have the results effected by the changes in cropping caused by "matching for height of frame" vs "matching for width of frame" in composition of your test image.
in some situations I prefer to use flash for my test light. I use a manual Metz flash on manual exposure. In combination with manual lenses (preferably the exact same lens this takes all things except sensor out of the equation) because light only comes from the flash, which having a duration of about 1/5000th of a second will mean that the shutter variation has no determination of exposure.