FS5: Sony FS5 Focus issues

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darcymu

Member
A while ago I noticed that I was having back focus issues while using some cine lenses. Focusing to infinity was not possible.
I do have the metabones Speedbooster adaptor. So after digging around I ended up trying to adjust the lens on the adaptor.
Metabones talks about this issue on their site. This didn't seem to work at first but then SOny said to upgrade the firmware.
THis helped a great deal and with the metabones adjustment, it seemed to work.

But lately I have noticed that when I shoot with my Canon lenses, focus at infinity still seems slighlty soft and I have even
been adjusting, and readjusting the adpator.

Then last night I was shooting a performance outside and when using Clear Image Zoom, I couldn't get a sharp focus with anything that was about 20' away or farther, the subjects were not sharp at all.

Has anyone come across this and might there be another resolution? I haven't ever noticed a focus issue with clear image zoom before.

Also. I have left the MB adaptor adjustment about 3/4 of a turn from where it was when I bought it.

Both FS5 and MB adaptor have had the firmware updated one month ago.

Darcy
 
Recently I tried my canon 50mm 1.4 on my FS5 and it doesn't focus to infinity. So I checked my 17-40 and same thing. I know there's a way to physically adjust the speedbooster, but I don't know how it will affect my lenses that don't have this issue.
 
Oh so you noticed that much of a difference between lenses as well. I wish there was an easy solution to this. I suppsoed buy Sony lenses. BUt, a $$$ issue.
 
darcymu said:
Oh so you noticed that much of a difference between lenses as well. I wish there was an easy solution to this. I suppsoed buy Sony lenses. BUt, a $$$ issue.
Click to expand...

Yeah, if my employer buys E-mount lenses then I'd use them gladly, but personally I have all canon EF and I won't waste money on E-mount glass. I would love that Fuji pair though.
 
Whenever there are back focus issues like this its quite tricky because the culprit could be your individual lenses, your speedbooster adapter or the camera itself. The only way to figure it out is to isolate each of those variables in turn. I would try to start with camera itself . See if you can borrow or rent some e mount lenses and check how those look. Next I would get a Canon adapter that's not adjustable like a metabones Mark IV and see if you can get infinity that way. Likewise try those lenses and adapters on other cameras.
 
All I can say on my side using the Fs5 with the Speedbooster is that my Canon lenses have always had an issue with infinity focus. I tweek sometimes the backfocus on the Speedbooster so that at least the Canon L 16-35mm 2.8 is sharp at 16mm on infinity. But then when you zoom you loose it. Even my Sony e-mount 18-110mm has the problem. If I want infinity I always have to go at the end of the focus and come back a little. For me that's maybe because these lenses are photo lenses not broadcast or cine lenses.
 
Lenny, good suggestion. I will actually try the regular metabones adaptor on my FS5 and then try the Speedbooster on my A7R2. Not sure why I didn't try this earlier.
Will check in after I try it.
 
Hi Lenny,
I will give Sony a call tomorrow but I think it is an issue with the Speedbooster. A regular adaptor is slightly sharper than the SB.
 
I guess I just answered in the other email but I will reply with more detail here.
I did try both the speed booster and regular meta bones adaptor. The latter does have a slightly sharper image. I also realized I had backed
off the adjustment on the SP and forgot to turn it forward a fullt turn again. I did this again and it does give me a sharper image than the
one I had the other day. Still not as sharp, though, as the regular adaptor. I wonder if this is as good as it will get.

Will reach out to Metabones and Sony tomorrow.
 
Dumb question: Are you looking at a monitor while you make adjustments to the SB? Does it provide functionality like a back focus adjustment?

Also, something I ran into(and can still have problems with) with my Optitek, if the lens isn't sitting in just the perfect spot in the adapter when you lock it down, back focus is off, which throws your witness marks are off and you cannot achieve infinity focus. And of course it will be worse on wider angle lenses.
 
darcymu said:
I did try both the speed booster and regular meta bones adaptor. The latter does have a slightly sharper image. I also realized I had backed
off the adjustment on the SP and forgot to turn it forward a fullt turn again. I did this again and it does give me a sharper image than the
one I had the other day. Still not as sharp, though, as the regular adaptor. I wonder if this is as good as it will get.

Will reach out to Metabones and Sony tomorrow.
Click to expand...

Of course a regular non-speedbooster adapter gives sharper images, there's simply no glass elements in it which mess with lens's original precisely designed optics. I also wonder what your hopes are for the conversation with Sony and Metabones, exactly what are you going to tell them that actually sounds concise? And why are you even mentioning firmware when this is a purely optical issue?
 
Actually, it was partially a firmware issue. When I first started noticing this, I was trying adjustments on the MB speebooster and nothing was helping. It would get a little better but still at infinity, the background was not at all sharp. So, I called Sony and they suggested updating the firmware as there were some issues with this. So, I updated the firmware and adjusted the SB and focus was much better.

I too, wondered how this would make a difference given it seemed like only an optical issue. But, it was infact partially a firmware issue.

Perhaps I am expecting too much at the end of the day. How sharp should this image be. It is ok, but not super crisp 150-200 feet from the camera.
 
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