@racer5 Would love to see some video with those Pentax lenses on a GH1, if you have inclination to shoot a few quick clips. Great stills - curious how it looks for video on the GH1. Are you using the RJ Lens Turbo (or just a regular adapter), and if so did you get the Pentax K to m43 or the Pentax PKA to m43 (the one for lenses without aperture rings)? Now I need to look for Pentax SMC lenses!

Has anyone else experienced binding/stiffness of the aperture ring when trying to adjust the aperture of manual nikon lenses on the RJ? It appears that the bottom of lens body is rubbing against the adapter as the aperture ring changes, and maybe there are some tolerance issues at the contact point of the adapter and lens?

@matt_gh2 @joethepro @Azo

Damn thanks guys, glad you like them. I'm really happy with the results this combo is delivering so far. Azo, I too started on Pentax; the K1000 was my first real camera, and I've held on to most of my original lenses for it. At one point I tested my K-mount fast 50s against each other and sold the two I liked least (was surprised that the SMC 1.4 beat out the Schneider Xenon).

Matt, I'm a fan of the Pentax SMC (super multi coated) primes most: just an 18, 50, and 85 is a hell of a set. And no footage with the RJ/PK yet, but planning to throw it on the BMPCC soon:)

Great shots, @racer5. I love my Pentax M 50mm 1.7. Wish there was a slim adapter for PK - Nikon so I could use it on my Nikon LensTurbo, but oh well. I may pick up a PK LensTurbo just for the reasons you listed, great lenses at decent prices!

Received my RJ Pentax K to m43 adapter, and am very pleased with it. Below are some off-the-card jpgs taken with the good old GH1. There are many great full frame Pentax K lenses out there, and unlike Nikon and Canon the market isn't flooded with competition for them. I can now use my set properly on m43. The shots below were taken wide, between 1.4-2.8.

@joethepro

it is like that. no problem in adapter or lens. neither pixel sensitivity. it is a physical lens construction behavior.

if you use a full frame lens on a full frame body you will perceive that the first fstop changes the amount of light in the center of the frame but the corners keep with same amount of light. as you stop down, the light in the center will calibrate with the light in the corners, and will decrease the vignetting, and the amount of light will be 1 fstop changing. the angle in which the light goes into the lens does not allow a perfect light distribution when the lens is wide open, so there is a small light changing from 1.4 to 2.0 but when you go from 2.0 to 2.8 the diafragm was already a little closed and if you take a look through the lens you will perceive that the amount of diafragm area is big in the first fstopdown. than from 2.0 to 2.8 the diafragm was already blocking the light which goes only to the center, and than there will be better light distribution and full fstop changing.

in my tests i perceived something around 0.8 fstop changing instead of 1 fstop but this is expected because the glass are not 100% transmission.

I just got mine, and I think I have a little too much focus past infinity, I think Ive lost a bit of close focus. I'll have to try adjusting it back a bit. There is severe binding with my Nikon AI 35mm F1.4 lens when trying to adjust the aperture. From 1.4 - 2 its fine, from 2 - 2.8 its a little stiff, and from 2.8 - 16 it is a serious workout to try to turn the ring. I know it is mounted properly, so it must just be a tolerance issue at the front of the adapter.

Either way, the images are turning our very nicely! I have noticed an improvement in the spherical abberation and sharpness at f/1.4, which is awesome because the lens is now usable wide open.

I did notice, however, that turning the aperture ring on the lens from f/2 to f/1.4 (f/1.0 effectively) definitely did not increase the brightness by one full stop. With a fixed ISO, the shutter speed only increased by about a third stop. Going from f/2.8 to f/2 on the lens (f/1.4 effectively) did increase the shutter speed by about a full stop. From f/4 - f/2.8 (f/2 effective) the shutter speed increase was definitely a full stop. This is apparently due to the phenomenon of smaller pixels becoming less efficient at grabbing larger and larger amounts of light as the aperture increases. It supposedly comes into play somewhere between f/2 and f/1.4 depending on pixel size, and is severely limiting by f/1.0, as I observed. Off-topic, I know, but still interesting nonetheless.

Edit: The more I think about this, it doesnt make complete sense, but perhaps it has to do with the angle of light hitting the sensor. Also, since smaller pixels cannot accept light at angles approaching parallel as much as larger pixels, this might make more sense in that regard.

@sakattaq76: great! what would you have to do to get infinity focus?

Mine arrived some days ago and it is amazing quality. There is no reason to get anything else. Perfect corner, edge and center sharpness. Fstop gain and built qualit is OK. New life to all lenses.

Just testing the RJ Focal Reducer Canon EF to m4/3 (with tripod mount) on my two favorite M42 lenses using the extra adapter M42 to Canon EF. So far so good, very happy with the results. No need to buy the seperate adapter for M42 lenses. Don't have focus to infinity but I don't care. If I want it I would make a micro adjustment.

Ok I just realized that all new Nikon G adapters come with the foot. My bad...

@Vitaliy_Kiselev Think I have been mislead by wishful thinking that made me see a Lens Turco Leica-M to MFT.

So there is no way to use any Lens Turbo with my Konica AR lenses, isn't it?

Any word yet of an upcoming Rollei QBM - Micro 4/3 Speed Booster?