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New 35 Lux announced
- Thread starter Terry
- Start date
GrahamWelland
Subscriber & Workshop Member
Peter,
The issue isn't whether you can necessarily focus accurately at f/1.4, it's more a case of shooting a set of shots at other apertures from the same place with the same focus indicated in the viewfinder. Depending upon the optimization of your 'lux you're likely to see the focus point move as you stop down until DoF takes over to keep it all in focus.
My 'lux focuses perfectly at f/1.4 and is optimized to do so. At 1m and from the same position and same focus in the viewfinder, if I stop down to f/2.8 or f/4 I'll see the exact point of focus shift back slightly in the captured image. In my case by f/5.6 it's hardly noticeable any more and by f/8 it appears perfect again.
The issue isn't whether you can necessarily focus accurately at f/1.4, it's more a case of shooting a set of shots at other apertures from the same place with the same focus indicated in the viewfinder. Depending upon the optimization of your 'lux you're likely to see the focus point move as you stop down until DoF takes over to keep it all in focus.
My 'lux focuses perfectly at f/1.4 and is optimized to do so. At 1m and from the same position and same focus in the viewfinder, if I stop down to f/2.8 or f/4 I'll see the exact point of focus shift back slightly in the captured image. In my case by f/5.6 it's hardly noticeable any more and by f/8 it appears perfect again.
glenerrolrd
Workshop Member
Of course it can be focused wide open if its calibrated correctly. Focus shift occurs when you stop the lens down .
100% crop showing focus point on vertical - just a one shot snap from one meter wide open @1.4 - no sharpen
- maybe just a lucky shot..:bugeyes:
now spare me all the BS
T@
The only valid issue regarding focus shift is will it matter in your typical shooting. If other factors like calibration,technique, ability to see are significant then focus shift gets lost in the details. If your typical subjects don t require the ability to get a clear sharp eye at 1M and most don t fine then its not important.
You seem to feel its Ok to refer to others perspectives as BS ....pretty arrogant . :thumbdown:
Peter-sorry but I have to ask that question: Am I wrong or did you just make and post a focus test ?
100% crop showing focus point on vertical - just a one shot snap from one meter wide open @1.4 - no sharpen
- maybe just a lucky shot..:bugeyes:
now spare me all the BS
T@
jonoslack
Active member
Knorp
Well-known member
Yep, it's a focus test all right.
And to my eye it shows clearly a slight front focus issue.
But hey what do I know ...
Let's call it a day, okay ?
:angel:
jonoslack
Active member
PeterA
Well-known member
Ok BS - was robably out of line - but then again no offence meant on a pesonal level..
for me the focus shift is a NON issue - I guess FOR OTHERS it is.
Nothing is going to change a person's beliefs and experiences or worries and concerns ..
I do have to say I laugh at the predantic nature of some here - but then again maybe I dont take this stuff as seiosuly as some. Ican't see front focus - b3ecause whilst I 'bel;ieve' I was focussing as accurately as i could from a metre away on a little horisontal line - I woudl never expect to be able to get spot on focus in such a tiny object so ( realtively) far away -
so the comment that it is front focussing - ( relevnt @ 100% crop...) may appeal to certain smug smugs..but to me it is irrelevant and invisible.
for my purposes there is more than enough accuracy and room for user error to make the issue unobservable and insignificant is guess what I am saying.
Cheers!
for me the focus shift is a NON issue - I guess FOR OTHERS it is.
Nothing is going to change a person's beliefs and experiences or worries and concerns ..
I do have to say I laugh at the predantic nature of some here - but then again maybe I dont take this stuff as seiosuly as some. Ican't see front focus - b3ecause whilst I 'bel;ieve' I was focussing as accurately as i could from a metre away on a little horisontal line - I woudl never expect to be able to get spot on focus in such a tiny object so ( realtively) far away -
so the comment that it is front focussing - ( relevnt @ 100% crop...) may appeal to certain smug smugs..but to me it is irrelevant and invisible.
for my purposes there is more than enough accuracy and room for user error to make the issue unobservable and insignificant is guess what I am saying.
Cheers!
jonoslack
Active member
Surely that's something we can all accept
I thought Bart had is tongue (at least partly) in his cheek - which was why it appealed to this smugmug
It's those little phrases like 'for me' and 'for my purposes' which should allow peace to break out all around
Have a nice day!
bradhusick
Active member
Jeez! It's just a lens! Buy it or don't buy it.
Happy shooting.
Happy shooting.
I don't know, off the top of my head I can think of stuff by Robert Frank that might lose something were they in "perfect focus". That said, I agree with the consensus in this thread that there is nothing BS about acknowledging the existence of focus shift as a technical issue that can come into play (whether you view photography rather loftily as an art form or simply something to do whilst mooching around).
One of the curious things I've noticed on these kind of internet forums is that those who are quite clearly amongst the biggest gearheads around are often the ones who shout loudest about how "the equipment doesn't matter" and how it's all "BS". I also think there's something ironic and amusing when someone demands to see "great pictures" that prove a technical point and then offers up a boring shot of some gear fondler lenses to make the counter argument. Incidentally, is that a bowl of crisps behind the keyboard?
jonoslack
Active member
Can't tell . . . . . . . . . . . they're out of focus
LCT
Member
Curious as well to show f/1.4 images to demonstrate focus shift or lack thereof. Try the same at f/2.8 or f/4 folks.
Peter Klein
New member
There are several issues here. Leica means "perfection" to some people, so anything less feels like a betrayal. Many people don't understand the difference between focus shift, back focus, camera adjustment, lens adjustment, and their technique. And our ability to detect a phenomenon with a digital camera may exceed our ability to control it in practical photography.
All fast lenses have focus shift as you stop down. Physics is physics. The question is how much, and does it matter? The 45-degree ruler test may seem ridiculous to some, but it can answer that question.
For years, with film, I thought that my 35mm Summicron IV was quite soft at f/2. After I got my M8, the ruler test showed me that it really isn't. It's just that it front focuses significantly at f/2. Now I know that if I want to use it wide open, I need to focus a little behind what I want sharp--on the subjects ears instead of their eyes. That's useful knowledge. I could have the 'Cron adjusted so it was perfect at f/2. But then f/2.8 - f/8 would be slightly back focused.
As for the 35 Summilux ASPH, see the attached photo. The rangefinder was focused on the 28 inch mark. See how the zone of focus shifts backwards from f/1.4 to f/4? Does it matter? Sometimes it does. I can either compensate slightly (say, by focusing on the nose instead of the eyes in a people shot), or avoid the stops from f/2.8-4. Or I can use another lens for f/2.8-4.
Or I can buy the new 35 Lux Asph for $5,000, and know that the floating elements have reduced the problem to the point where it won't matter much for all practical purposes, even if Erwin can show that it's still there to some extent.
Knowing your lenses is a good thing. Knowledge is power. Especially when you're using a sensor with no anti-alias filter, when "perfection" was previously defined using film.
All fast lenses have focus shift as you stop down. Physics is physics. The question is how much, and does it matter? The 45-degree ruler test may seem ridiculous to some, but it can answer that question.
For years, with film, I thought that my 35mm Summicron IV was quite soft at f/2. After I got my M8, the ruler test showed me that it really isn't. It's just that it front focuses significantly at f/2. Now I know that if I want to use it wide open, I need to focus a little behind what I want sharp--on the subjects ears instead of their eyes. That's useful knowledge. I could have the 'Cron adjusted so it was perfect at f/2. But then f/2.8 - f/8 would be slightly back focused.
As for the 35 Summilux ASPH, see the attached photo. The rangefinder was focused on the 28 inch mark. See how the zone of focus shifts backwards from f/1.4 to f/4? Does it matter? Sometimes it does. I can either compensate slightly (say, by focusing on the nose instead of the eyes in a people shot), or avoid the stops from f/2.8-4. Or I can use another lens for f/2.8-4.
Or I can buy the new 35 Lux Asph for $5,000, and know that the floating elements have reduced the problem to the point where it won't matter much for all practical purposes, even if Erwin can show that it's still there to some extent.
Knowing your lenses is a good thing. Knowledge is power. Especially when you're using a sensor with no anti-alias filter, when "perfection" was previously defined using film.
GrahamWelland
Subscriber & Workshop Member
I think Peter nailed it. I couldn't say it better myself. :thumbs:
LCT
Member
The latest pre-asph Lux 35/1.4 for instance but not the CV 35/1.4 SC.
GMB
Active member
Fully agree. I love to shoot portraits of my family, and I love the look of the f1 Nocti, the 75 lux, the 50 lux, and the 75 cron wide open. My M8 back focused so I had a lot of nice shots with sharp ears--until I send the camera to Solms for adjusting. After that it worked fine and I know that when I missed one, it was my fault.
When I got the M9 in December, all of the lenses front focussed, and I now have sharp noses. Today I'll ship the whole stuff to Solms. Of course, one can try to compensate but why paying so much cash for a prime product, on of the main features of which should be the fast and precise focusing, and then do guess focusing.
Of course, there are also the shots where you try to capture a certain situation etc., and where the precise focus does not matter that much. But sometimes, in particular when you shoot wide open, the visual effect of an image depends on you nailing the focus. How would the attached example look if the focus was not on the eye?
View attachment 31378
Not sure how someone defines a photo as a "success?" Money? Publication? Pleasure? What I know is that for me the shots matter, that friends I show them to like them, and that some of them are not any worse than photos I saw published.
Just my 2c.
