Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
11-16-2017, 06:47 AM   #1
New Member




Join Date: Mar 2016
Posts: 9
PK to m4/3 focal reducer

Does anyone have any experience with using pentax lenses on m4/3 body using some of those relatively cheap focal reducers (like this)?

I know everything needs to be manual using these adaptors, but I'm curious how you change the aperture if your lens doesn't have a aperture ring.

It'd be great if anyone could share some sample images taken at different apertures to see how the sharpness compares with mounting the lens on a native Pentax DSLR.

With the new Panasonic G9 coming out soon with both great still and video feature in a relatively small body, I'm really considering moving to the m4/3 system. But I'm reluctant to completely get rid of my Sigma zoom lenses like the 17-50 and 50-150 f2.8 since they are pretty sharp. It would be ideal if these focal reducers can make these lenses somewhat usable on the m4/3 body.


Last edited by MohoWu; 11-16-2017 at 06:53 AM.
11-16-2017, 06:57 AM   #2
Site Supporter
Site Supporter
timw4mail's Avatar

Join Date: Apr 2017
Location: Driving a Mirage
Photos: Gallery | Albums
Posts: 1,669
QuoteOriginally posted by MohoWu Quote
I know everything needs to be manual using these adaptors, but I'm curious how you change the aperture if your lens doesn't have a aperture ring.
You can't change the aperture without an aperture ring, when adapting a lens.
11-16-2017, 07:07 AM   #3
Loyal Site Supporter
Loyal Site Supporter
UncleVanya's Avatar

Join Date: Jul 2014
Photos: Gallery | Albums
Posts: 20,915
I haven't used a focal reducer, but I do shoot m43 sometimes with an adapter and my k mount lenses. The adapter I have had a ring that says "open/close" and is labeled pentax DA to m43. The open close is an infinitely variable turn to operate ring. The effect is to full ofy open or fully close the aperture or any position in between. Shooting in any mode that meters and doesn't expect to change aperture for you works fine but you won't precisely know what aperture you have set unless you pre-calibrate an adapter for a particular lens and Mark the ring appropriately. It might be possible to make some paper bands to attach and remove to represent the marks but I haven't tried.
My read on the cheap focal reducing adapters is that they are very soft outside the very center and aren't usable until several stops stopped down. This isn't true of the very expensive original devices. Because of this I only use adapted lenses where the focal length makes sense. So my FA 31 as a fast semi normal lens. My FA 77 as a long portrait lens. My Rokinon 8mm as a very wide prime.
Largely however I use m43 lenses natively for the size and weight. Most of the ones I use are slow but have good image quality.

---------- Post added 11-16-17 at 09:13 AM ----------

This probably belongs in the non Pentax section.

Last edited by UncleVanya; 11-16-2017 at 07:12 AM.
11-16-2017, 07:35 AM   #4
Site Supporter
Site Supporter




Join Date: Sep 2006
Location: Mississippi, USA
Photos: Gallery
Posts: 853
As others have said the cheap adapter don't work with DA or FAJ lenses. I like shooting with ST or PKA mounts on my m4/3. Simple in Av mode.
It wore off fast for me and I expanded my collection of m4/3 glass. If you go here.......... Forums | Mu-43.com - Micro Four Thirds User Group and look under adapted lens catagory you can see what others are using and the results.

Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adapter, aperture, fa, lens, lenses, m4/3, m43, pentax, pk to m4/3, tripod
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Is anyone making a PK-FX focal reducer? zoltan1983snapper Pentax SLR Lens Discussion 3 07-21-2019 04:49 PM
Lens coverter vs focal reducer lotech Pentax Camera and Field Accessories 3 09-27-2016 07:07 AM
m42 to Pentax K focal reducer raff89 Pentax SLR Lens Discussion 19 01-13-2016 04:11 PM
Pentax Q and Focal Reducer ripper2860 Pentax Q 23 12-27-2015 12:26 PM
$199 focal reducer speed booster adapter Pentax PK K to Sony NEX jogiba Pentax Price Watch 91 12-07-2014 09:19 AM



All times are GMT -7. The time now is 11:40 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top