[PiDicus Rex]

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Not what I was actually referring to.

I'm totally sick of reviewers claiming a Focal Reducer "Makes the lens wider".

A 50mm lens has a fixed 'Angle of View', regardless of what sort of camera, focal reducer, tele-expander, that the lens is attached to.

But some reviewers continue to say focal reducers make the lens wider, rather then 'reduces the amount of image circle lost by cropping'.

It's important, as some idiot somewhere will mis-understand and think 'I'll put my FF PK 50mm on my PK to E focal reducer, and that will give me 35mm on my A7s in FF Mode.

The rest of us won't be surprised to see that person complaining the lens vignettes....

The compressed image circle is what makes the lens appear faster,... and is exactly the reason they were invented for astronomers, long before photographers and cinematographers got a hold of them

I need such an adapter for MFT... but on the Fotodiox site I can only find adapters without aperture control?

I gutted the faux-iris out of one of these, to test on the M4/3 mount I made for my Cion. Soft edges and vignettes a touch (brightness correction in post fixes), but for a cheap unit, it's not too bad for the money - I wouldn't use it on a feature film, but on an artsy project, the soft edges are pretty pleasing.

Focal Reducer for Canon EF Lens to Micro 4/3 Mount Camera Speed Booster - to Micro 4/3 mount - Lens Mount Adapters

I grabbed the cheapo PK-EF ring from the same mob, and adjusted the locking spring to stop the lens spinning in the mount during focus pulls.

Remind me to link some footage from last weekends test shoot / showreel scene in a week or so.

[kadajawi]

I gutted the faux-iris out of one of these, to test on the M4/3 mount I made for my Cion. Soft edges and vignettes a touch (brightness correction in post fixes), but for a cheap unit, it's not too bad for the money - I wouldn't use it on a feature film, but on an artsy project, the soft edges are pretty pleasing.

Focal Reducer for Canon EF Lens to Micro 4/3 Mount Camera Speed Booster - to Micro 4/3 mount - Lens Mount Adapters

I grabbed the cheapo PK-EF ring from the same mob, and adjusted the locking spring to stop the lens spinning in the mount during focus pulls.

Remind me to link some footage from last weekends test shoot / showreel scene in a week or so.

Wow. I was thinking more about adapters without glass, but at this price point (those are Australian Dollars?) I wouldn't mind a focal reducer! I found the Roxsen PK to MFT for 65 Euro. Focal Reducer Speed Booster Adapter Pentax K mount PK lens to Micro 4/3 M43 E-P7 | eBay
According to the description, I can control the aperture with it? An adapter with aperture control already costs 25 Euro... And oddly enough, the PK to MFT focal reducer isn't available on the Roxsen website...? But according to this video Roxsen does make the PK adapter.

You Tube

You Tube

However the reviewer says you can't change the aperture...

I've shot this video on the GX80 with a 35-100 Panasonic lens. In camera audio, standing right next to the speaker (roughly 30-50 cm from the subwoofer and main speaker). It's amazing what volumes these tiny microphones can withstand! FilmConvert to tweak the colors/give it a look and add some grain to the video.

You Tube

You Tube

There's a lot more under changing light conditions on the channel... Anyway I'm pretty impressed by this little camera.

[PiDicus Rex]

Yes, Aussie dollars.

The one I grabbed is EF mount, and the iris is to replace the camera controlled one in the Canon lenses.

I pulled it out because it interfered with the aperture linkage on my KM/KA lenses, and I noted it seemed to vignette more then just control exposure.

Without it, and with the PK-EF ring, there was plenty of clearance inside for the iris control on PK lenses.

[audiobomber]

According to the description, I can control the aperture with it? An adapter with aperture control already costs 25 Euro... And oddly enough, the PK to MFT focal reducer isn't available on the Roxsen website...? But according to this video Roxsen does make the PK adapter. Roxsen Pixco Focal Reducer Speed Booster real world review - YouTube However the reviewer says you can't change the aperture...

The reviewer is correct, the m4/3-PK version can only control aperture using the aperture ring on the lens. If your lens has no aperture ring, it remains fully closed.

He's not too clear on crop factor, but it's not hard to determine. The focal reducer is .72X, so that is how it impacts both focal length and aperture. A 50mm f1.4 on FF becomes 100mm f2.8 equivalent on m4/3, and 72mm f2.0 equivalent with the Roxsen on a m4/3 camera.

He's a bit too generous regarding impact on IQ, the extra glass does increase aberrations (flare, CA, field curvature, distortion, coma). Whether this bothers you depends how fussy you are, and on the lens being used. Veiling flare especially becomes much more likely. Use a good lens and a hood at all times. I don't shoot video, but I believe it is far less demanding regarding sharpness and aberrations compared to stills shooting, so that may explain his views on IQ with the Roxsen.

[kadajawi]

The reviewer is correct, the m4/3-PK version can only control aperture using the aperture ring on the lens. If your lens has no aperture ring, it remains fully closed.

He's not too clear on crop factor, but it's not hard to determine. The focal reducer is .72X, so that is how it impacts both focal length and aperture. A 50mm f1.4 on FF becomes 100mm f2.8 equivalent on m4/3, and 72mm f2.0 equivalent with the Roxsen on a m4/3 camera.

He's a bit too generous regarding impact on IQ, the extra glass does increase aberrations (flare, CA, field curvature, distortion, coma). Whether this bothers you depends how fussy you are, and on the lens being used. Veiling flare especially becomes much more likely. Use a good lens and a hood at all times. I don't shoot video, but I believe it is far less demanding regarding sharpness and aberrations compared to stills shooting, so that may explain his views on IQ with the Roxsen.

That's a shame. They can add the aperture control at little extra cost on regular adapters, but they can't fit it to a focal reducer? After all aperture control is pretty trivial and entirely mechanical on Pentax.

I absolutely do need aperture control, as the main lens I want to use is the DA50. My 80-200 would work regardless, but there isn't too much of an advantage to my 35-100 m4/3 lens.

[madbrain]

The following adapter appears to have an aperture dial that should work with DA lenses .
According to the FAQ, it will ONLY work with lenses without an aperture ring.

amazon.com : Fotodiox Lens Mount Adapter - Pentax K Mount (PK) SLR Lens to Micro Four Thirds (MFT, M4/3) Mount Mirrorless Camera Body, with Built-In Aperture Control Dial : Camera & Photo?tag=pentaxforums-20&

For lenses with an aperture ring on them, the following adapter would be required :

https://www.amazon.com/Fotodiox-Adapter-Olympus-Panasonic-Cameras/dp/B003EAS...to+micro+4%2F3

[sqrrl]

There is another one called a "Fotasy Pro Pentax DA K Mount lens to Micro 4/3 MFT..." Which has an aperture control.

It turned up quickly, was well made, and functioned fine for stop down - though not really for 'on the fly' adjustments for video as the throw is really short on the aperture control (it engages the aperture post on the K mount lens rather than having it's own aperture).

I won't recommend it as when I brought one it simply didn't fit my camera - after a bit of investigation I discovered that it was a fuji to k mount which had been converted by dint of putting a new sticker over the label on the box. I don't know if they actually do panasonic at all, or if they just rely on people not wanting to spend more on return postage than they paid in the first place (they demanded insured signature return postage) - suffice it to say I'm avoiding amazon as they seemingly have no issue with business practices like this.

Maybe one day I'll get to play with one of the fuji's, till then it's just a paper weight.

[kadajawi]

I bought a quenoX adapter from enjoyyourcamera, which arrived today. It works, and seems rather well made. However it lacks the reducer optics. I'd really like a focal reducer that also has the aperture ring, but until then (and to get more out of my lenses) the quenoX will do.

[kadajawi]

I found a major disappointment with my GX80: Using an adapter I can't compensate exposure. Makes no sense to me, it doesn't know the aperture, but so what? If I dial in all settings manually, it will show me how much I'm over- or underexposing. So clearly it knows...

[madbrain]

I found a major disappointment with my GX80: Using an adapter I can't compensate exposure. Makes no sense to me, it doesn't know the aperture, but so what? If I dial in all settings manually, it will show me how much I'm over- or underexposing. So clearly it knows...

Are you then expecting to change both ISO and shutter speed ? If only one of them, surely you can just change that one parameter. But if you want both at the same time, yes, you would need exposure compensation for that.

[kadajawi]

Are you then expecting to change both ISO and shutter speed ? If only one of them, surely you can just change that one parameter. But if you want both at the same time, yes, you would need exposure compensation for that.

I expect to select, say, the shutter speed, and the camera takes care of ISO and aperture (or in the case of a manual lens, the ISO). Basically I want auto ISO, and I don't think such a thing exists when using an adapter (unless you're ok with 0 EV exposure compensation. But the result seems overexposed to me, so I'd like to dial it down). Problem with fixed ISO is that in case the light changes (say clouds go away) it won't adjust accordingly. And I don't understand why there is just no auto ISO where you can compensate exposure by hand, when using an adapter (but there is when using m43 lenses).

[madbrain]

I expect to select, say, the shutter speed, and the camera takes care of ISO and aperture (or in the case of a manual lens, the ISO). Basically I want auto ISO, and I don't think such a thing exists when using an adapter (unless you're ok with 0 EV exposure compensation. But the result seems overexposed to me, so I'd like to dial it down). Problem with fixed ISO is that in case the light changes (say clouds go away) it won't adjust accordingly. And I don't understand why there is just no auto ISO where you can compensate exposure by hand, when using an adapter (but there is when using m43 lenses).

Makes sense. I just tried the Fotodiox adapter on my Sigma 10-20. I am able to change the aperture by rotating the aperture ring.
But there are a bunch of limitations in the camera. In particular, there is no focus peaking, and zero indication of focus point, which is really odd. The K-30 is able to do focus peaking even on manual focus lenses. This is very useful when turning the focus ring. Manually focusing without focus peaking is not easy. The viewfinder in the camera is just so-so - it is small and an EVF, so only so many fps. If using an aperture other than wide open, there would be too little light to be able to focus manually. I think the adapter will work mostly for tripod use I intended, and not really anything else.

Also, playing with the GX85 and the Lumix 12-32 lens, I found really terrible barrel distortion on the wide end. DXO Optics Pro (free version I got last year) is able to superbly compensate for it, and gets me straight lines as intended, out of pictures of that look very curved. I have not unpacked the 45-150 lens yet. I hope it is better.

[audiobomber]

I have four NEX to PK adapters. All support auto ISO, exposure compensation and focus peaking on my a6000 and I can move the AF point all over the frame. The only difference between shooting with a Pentax lens and a Sony is that I don't have AF and electronic aperture control.

[kadajawi]

Makes sense. I just tried the Fotodiox adapter on my Sigma 10-20. I am able to change the aperture by rotating the aperture ring.
But there are a bunch of limitations in the camera. In particular, there is no focus peaking, and zero indication of focus point, which is really odd. The K-30 is able to do focus peaking even on manual focus lenses. This is very useful when turning the focus ring. Manually focusing without focus peaking is not easy. The viewfinder in the camera is just so-so - it is small and an EVF, so only so many fps. If using an aperture other than wide open, there would be too little light to be able to focus manually. I think the adapter will work mostly for tripod use I intended, and not really anything else.

Also, playing with the GX85 and the Lumix 12-32 lens, I found really terrible barrel distortion on the wide end. DXO Optics Pro (free version I got last year) is able to superbly compensate for it, and gets me straight lines as intended, out of pictures of that look very curved. I have not unpacked the 45-150 lens yet. I hope it is better.

There is focus peaking. Somewhere in the settings (it's a bit overwhelming). Under the spanner with the C next to it, on page 4. Focus peaking. You can also adjust how sensitive it is, and what color you want. It works during video, and with manual lenses.

The viewfinder isn't the greatest, yes, but it works. As for the fps, I find it quite responsive, and you can chose between 30 and 60 fps. It's under the spanner (without C), on page 2. I find 30 fps enough to be honest, and that's supposed to save battery.

12mm is quite wide already, and Lightroom automatically does lens corrections. I'm quite happy with the lens. It's sharp (sharper than my Pentax lenses, including the DA 50), it's tiny and very light. Great for travelling. I don't have the 45-150 though, as I mostly care about having a small and light package.

[madbrain]

There is focus peaking. Somewhere in the settings (it's a bit overwhelming). Under the spanner with the C next to it, on page 4. Focus peaking. You can also adjust how sensitive it is, and what color you want. It works during video, and with manual lenses.

The viewfinder isn't the greatest, yes, but it works. As for the fps, I find it quite responsive, and you can chose between 30 and 60 fps. It's under the spanner (without C), on page 2. I find 30 fps enough to be honest, and that's supposed to save battery.

12mm is quite wide already, and Lightroom automatically does lens corrections. I'm quite happy with the lens. It's sharp (sharper than my Pentax lenses, including the DA 50), it's tiny and very light. Great for travelling. I don't have the 45-150 though, as I mostly care about having a small and light package.

Thanks. I found out afterwards that it works. Apparently there was only a very small area in focus and I couldn't see it. I changed the color for the focus peaking. Changed to full screen for MF assist also. Haven't tried it yet as I have the 12-32 lens attached at the moment.

Lightroom may do the lens correction, but I use Aftershot, and even though it has a camera profile for the GX85 that I downloaded, it is not doing any lens correction on the RW2 files. It just shows "uncalibrated lens". Bummer given that this is the kit lens.

I'm guessing the JPG output have the barrel distortion automatically corrected in camera. I would have to shoot in JPG + RAW to compare. I have been shooting RAW only for years with my K-30.

Yes, 12mm in m43 is wide - that is 24mm focal in 35mm equivalent. The Sigma 10-20 at 10mm is 15mm focal in 35mm equivalent - much wider. I almost never use it. The only reason is for shooting indoor in very tight spaces. My 8ft harpsichord happens to be in a corner in my music room, which also contains a 9ft2 grand piano. When I play, my back is almost right against the wall. There is certainly not enough space to mount a tripod behind. So, I put it on the side instead. My HG21 camcorder didn't have a wide enough lens for what I wanted to do in that case. Sigma 10-20 did, but the video on the K-30 just sucked.
Sigma 10-20 at 10mm wide open + DMC-GX85 appears to be a very good combo for this use. One day, I should install a tripod mount on my ceiling to show all my playing a at proper angle. It's an 11ft ceiling, though. I'm guessing such a mount would cost more than the camera.

I still haven't opened the box for the 45-150. I really should, just to make sure it's OK

Been too busy doing other things. Really enjoying the 4K photo and Post focus modes much more than I thought I would. Of course, Post focus requires a native AF lens - doesn't work with the PK adapter ...
But I'm also discovering that the 4K30 video provide really good video frames that I have been extracting with PowerDirector and VLC. 8 MP is good enough to print at most sizes I can do at home. I haven't tried a 13x19 print but I expect it would be OK.
The cat videos in 4K I have done are not all that interesting to watch, but they allow me to extract high quality frames that can be great photos. All those people who are poo-pooing video in other forums on this site and claiming they have no use for video and don't want to pay for it are completely missing out.
4K video capture is actually a great way to extract photos. Like having a 30fps camera. Of course the bit rate is "only" 100 Mbit, and the CODEC is not RAW. But still, the result is quite impressive. I guess that's why I want the GH5s to capture with the 400 Mbps CODEC