In my experience CV M-mount lenses (especially the ones released in recent years) typically have hard infinity that is spot-on and can be used for optimal corner-to-corner sharpness on long distance shots since that seems to be more strictly expected by M-mount system users.
I don't have 50/2 and 35/2 in M-mount (since I always get the E-mount versions when available), but I did get the recently released 50/3.5 APO-Lanthar and that has spot-on hard infinity with my Rayqual adapter on my Sony cameras (A7CII etc.). Same has been true with all of their newly released VM lenses that I have acquired in the last couple of years. Their older releases weren't always spot on with this but I think nowadays they are making sure that newly released M-mount lenses are fully accurate in this regard.
When adapting M-mount lenses to E, the adapter thickness is often an issue though as very few adapters are designed to have precisely the right thickness (Rayqual adapters are designed to be precisely right). With slightly thinner adapters (such as Voigtländer VM-E adapters), hard infinity will become slightly beyond infinity again.
With precise-thickness adapters, there might be cases where certain lenses don't reach optimal infinity as there can always be some variation (especially with older lenses). Also some lenses have field curvature characteritstics (esp. when adapted) that make it so that focusing a bit further than optimal infinity in the center could help mid-frame / corners etc. Therefore it's good to have a couple of different adapters. I personally have Rayqual and CV VM-E close focus adapter II.
It's not a great idea to adapt CV 50/2 and 35/2 M-mount versions to Sony though as based on Fred's reviews and others, those 2 VM lenses relatively much of their IQ when adapted to Sony (due to thicker sensor filter stack). However, 50/3.5 APO adapts very well to Sony.
Adamwilbert wrote:
Is this true of the m mount versions too?
Juha Kannisto wrote: Adamwilbert wrote:
Just picked up a used e mount 50mm apo.
Is it normal for them to focus past infinity?
My copy will focus at infinity if I put the actual infinity mark at the dot, but that line after it seems well past it even for VERY distant subjects.
Yes, all CV E-mount APO-Lanthars are designed so that they allow focusing past infinity. Most other CV mirrorless lenses are also the same way.
From their E-mount lenses (I've had all of them except 12/5.6), I can use hard infinity on 15/4.5, 21/3.5 and 40/1.2 (original and SE) and with all others it's been necessary to focus a bit before hard infinity.
With their X-mount lenses only 18/2.8 and 27/2 are designed so that hard infinity can be utilized and all others allow focusing a bit further.
In my experience CV M-mount lenses (especially the ones released in recent years) typically have hard infinity that is spot-on and can be used for optimal corner-to-corner sharpness on long distance shots since that seems to be more strictly expected by M-mount system users.
I don't have 50/2 and 35/2 in M-mount (since I always get the E-mount versions when available), but I did get the recently released 50/3.5 APO-Lanthar and that has spot-on hard infinity with my Rayqual adapter on my Sony cameras (A7CII etc.). Same has been true with all of their newly released VM lenses that I have acquired in the last couple of years. Their older releases weren't always spot on with this but I think nowadays they are making sure that newly released M-mount lenses are fully accurate in this regard.
When adapting M-mount lenses to E, the adapter thickness is often an issue though as very few adapters are designed to have precisely the right thickness (Rayqual adapters are designed to be precisely right). With slightly thinner adapters (such as Voigtländer VM-E adapters), hard infinity will become slightly beyond infinity again.
With precise-thickness adapters, there might be cases where certain lenses don't reach optimal infinity as there can always be some variation (especially with older lenses). Therefore it's good to have a couple of different adapters. I personally have Rayqual and CV VM-E close focus adapter II.
It's not a great idea to adapt CV 50/2 and 35/2 M-mount versions to Sony though as based on Fred's reviews and others, those 2 VM lenses relatively much of their IQ when adapted to Sony (due to thicker sensor filter stack). However, 50/3.5 APO adapts very well to Sony.
Adamwilbert wrote:
Is this true of the m mount versions too?
Juha Kannisto wrote: Adamwilbert wrote:
Just picked up a used e mount 50mm apo.
Is it normal for them to focus past infinity?
My copy will focus at infinity if I put the actual infinity mark at the dot, but that line after it seems well past it even for VERY distant subjects.
Yes, all CV E-mount APO-Lanthars are designed so that they allow focusing past infinity. Most other CV mirrorless lenses are also the same way.
From their E-mount lenses (I've had all of them except 12/5.6), I can use hard infinity on 15/4.5, 21/3.5 and 40/1.2 (original and SE) and with all others it's been necessary to focus a bit before hard infinity.
With their X-mount lenses only 18/2.8 and 27/2 are designed so that hard infinity can be utilized and all others allow focusing a bit further.
Sep 29, 2024 at 10:09 PM
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