Originally posted by Nicolas06 osv, yes the A7 is going to have significantly better low light than K3... A bit less than 1stop. (0.9 ?)
So how does it apply?
- using any lense not native to FE, losing AF you get 0.9 stop gain.
i know that english isn't your first language, but i see where you are going, i'll try to sum it up.
a7 has ~.9ev better iso performance over k3, according to you?
~.9ev minus lea4 light loss ~.3ev =
a7 has ~.6ev better iso performance over k3, with the lea4 on it?
makes sense to me, i guess?
Originally posted by Nicolas06 - using FE lens you get 0.9 stop gain but there only one fast lens (55mm f/1.8). Overall FE lenses are one stop slower than other lenses from other mounts, including Pentax offering. No practical gain here as anybody on APSC can just use f/2.8 instead f/4 zoom or a stop faster prime to negate the dof control and high iso adventage of the sensor size.
if fastest aperture was the goal, you could mount any f/.95-1.2 lens, from any company, on the a7.
a7 wins, k3 loses again.
Originally posted by Nicolas06 As some have already mentionned, Sony didn't make new body (or new lenses) for a-mount lately.
we already covered this? doesn't b&h list eleven ff f/2.8 zoom lenses for sony a-mount, and three ff f/2.8 zoom lenses for pentax?? none of which were made by pentax?
no ff future for pentax.
Originally posted by Nicolas06 Now somebody with a D610 (or really any Nikon FF... based ironically on Sony sensors) get significantly better high iso performance than the A7.
i don't agree with that at all... but we are talking about pentax here, not nikon.
so what you are claiming there is that nikon blows pentax completely out of the water wrt to high iso performance.
so why didn't you buy nikon instead of pentax, since you think that nikon is so much better?
another failed strawman argument... bring in something completely irrelevant(nikon) to prove a non-existent point.
---------- Post added 12-06-2014 at 12:04 PM ----------
Originally posted by Nicolas06 Let say it differently... The light loss for the 70-200 G on DxO show 3.2 T stop. Let's add the lea4... and the effective T-stop is more 3.7 (if we count 0.3Ev loss from the lea4).
taking your dxo claim at face value...
you just told us that the a7 has ~.6ev iso better performance over the k3, so the a7 is still better
when the a7ii comes out, the a7 is liable to go on sale for maybe $200 more than a k3.
you can mount any pentax lens to an a7, and get an evf that gives you real manual focusing capability.
hmmm...