28mm CV Ultron F2.0

[Jim Evidon]

28mm CV Ultron F2.0:

I am looking for a 28mm lens. I have several CV lenses plus a few Leica lenses, but I would prefer to purchase CV because of my experience and the price.

Sean Reid tested the 28mm f2.0 CV Ultron and found problems with focus shift and said that he would test other examples to see if this was an anomaly or if it was common to this lens. He never did so.

So, to you 28mm f2.0 Ultron users, I ask: do you have a focus shift problem and, if so, how do you deal with it?😕

 

[randomm]

I've seen focus shift in my copy when mounted on my E-PL1.

How do I deal with it? I don't. I shoot film through it, mostly either wide open in available light or at f5.6+ outdoors.

I don't know if this varies from copy to copy. Biggest difference in my copy is between f2 and f2.8. At f4 deeper DoF starts taking care of shift. Does that mean that f2.8 is unusable? I don't know to be honest, I don't really worry about these sort of things, just shoot 🙂

 

[efix]

I'm not using the 2.0 version, but the older 1.9 version. I can't thus compare the two, but from what I've heard from others, the 1.9 is far better suited for digital than the 2.0. All I can say that it shows no focus shift whatsoever, has wonderful colour rendition (to my taste at least), good contrast which gets slightly higher-than-medium when stopped down, and is reasonably sharp already wide open, with some very very minor "glowing", which is hardly noticeable (only when pixel-peeping really, and FAR less than the 35/1.4 Nokton at f/1.4). You'll need an adapter for it (go with a Voigtländer or Leica one, 'cause cheap ones will cause trouble), but all in all that'll still be less money than the new 2.0, and -- if what others say is true -- you'll have the better lens.

Here are some pictures if you care: http://www.efixmedia.de/photography/tag/ultron-281-9/

Oh, and lest I forget: I find it's bokeh rather smooth and pleasing!

 

[helmbrecht]

Hi,

in the last months I was looking for a fast 28mm for my M8 too.

I had both CV's, the Ultron 28mm 1.9 and the newer 28mm 2.0 and the Summicron 2.0 for a couple of weeks on my camera. Finally I bought the older version of the Ultron ( the one with f 1.9) for some reasons.

(1) Focus shift
The focus shift on the 28mm 2.0 was really quit obvious. f 2.0 and 2.8 was the focus ok, between 2.8 and 5.6 focus was extremely off. Generally I think the discussion about focus shift is overacted. I also use the CV 40mm 1.4 and there you notice focus shifting at f 2.8 and 4.0 too. To see it you need a test chart and a tripod or of take portraits at minimal distance. Normally it is not visible. But the Ultron 2.0 showed very significant shifting. Intolerable for me.

(2)character of the lens and Bokeh
The newer Ultron is very very contrasty. Especially with uv/ir cut filter. Therefore it is already very sharp and contrasty at f 2.0. But it has a very hard character for my taste. The older Ultron on the other hand is not so contrasty a 2.0, but very smooth and renders beautiful. It is not so contrasty and it seems that it is at 1.9/2.0 not so tack sharp like the newer Version or the Summicron. But adding more contrast/black in Lightroom and you have the same performance. Only the Cron is that clear and sharp that it performs everything out. But this all happens on a extremly high level. Therefore I bought the (second hand) Ultron for 300 Euros. The Cron was about 2000 Euros and for my budget I didn't see that big advantage. Because already at 2.8 or 4.0 they are equal.
Especially the Ultron 1.9 renders very nice like most older CV M39 lenses. I prefer them of the harsh and contrasty newer CV and Asph. lenses.

(3) If you don't need speed take a Leica Elmarit. It's small and compact, tack sharp, and renders beautifully. On the M8 I need the fastest lenses I can get to compensate the high ISO weakness...

(4) At the end it was battle between the Ultron 1.9 and the Summicron. But like I said before, the price of the Cron was to high for the extremely minimal advantage at f 2.0. More over the older CV have a very nice character, like the older Leica lenses in the pre aspherical periode. I like that.

a last not: Get a original Leica or Voigtlander Adapter if you buy a M39 camera. Anything else is awful. Save yourself this fu**ing bad experience 🙂

merry christmas!

cheers
christian

 

[gho]

Hmm, I have used the 28/2 Ultron for quite some weeks now and at the moment it is my favourite lens.

I do not find it especially contrasty, say, compared to the 35/2.5 C, quite on the opposite and focus shift has not been a problem for me yet. It may be there, sure, but mostly, when stopping this lens down, I want to have as much in focus as possible.

What I especially like about this lens is the virtual absence of barrel distortion. But maybe it is just my copy and ymmv.

Here are some pictures:

Tri-X@1600

Adox Pan 400@800

 

[Harry Lime]

Almost every lens currently on the market has focus shift, including the best of Leica glass.

The vast majority of lenses made since the inception of photography have some amount of focus shift.

Some of the biggest names in photographic history shot with the Sonnar 1.5/50, which has severe and noticeable focus shift and somehow they still managed to make great photographs.

I own the VC 2/28 and shoot it on analog M bodies. It is a great lens and currently one of the best bargains in photography. Focus shift is not a problem. You may see it under some circumstances when shooting at f2 and close up, if you are zoomed in 800% in Photoshop and looking for it.

The lens is sharp, delivers good contrast and flare suppression. It's a steal.

Buy it, shoot it, enjoy, don't worry about the pixel peepers.

 

[Harry Lime]

(1) Focus shift
The focus shift on the 28mm 2.0 was really quit obvious. f 2.0 and 2.8 was the focus ok, between 2.8 and 5.6 focus was extremely off.
Generally I think the discussion about focus shift is overacted. I also use the CV 40mm 1.4 and there you notice focus shifting at f 2.8 and 4.0 too. To see it you need a test chart and a tripod or of take portraits at minimal distance. Normally it is not visible. But the Ultron 2.0 showed very significant shifting. Intolerable for me.

That is very odd and I'm sorry to say makes almost no sense since it's a 28mm. At f5.6 a 28mm delivers a massive amount of DOF; certainly more than enough to eliminate any focus shift.

Since this is a wide angle lens you should only notice focus shift issues wide open and close up... Maybe the focus cam is off or operator error?

 

[gho]

Just wanted to add, I do not know how this one would perform on a digital camera.

 

[helmbrecht]

That is very odd and I'm sorry to say makes almost no sense since it's a 28mm. At f5.6 a 28mm delivers a massive amount of DOF; certainly more than enough to eliminate any focus shift.

Since this is a wide angle lens you should only notice focus shift issues wide open and close up... Maybe the focus cam is off or operator error?

Hi,

Focus Shift is never noticeable wide open, only stopped down. I'm not a pixel peer, but the focus shift on my (!!) was extremely visible, also at f 5.6

You are free looking in to the Leica Forum, looking for the statements of Jean Raid (or look at his site, but there you've to pay). There are a lot of discussion about focus shift between 2.8 and 5.6

Maybe my lens was extremely off, and others are not. i'm not technician and I don't like to discuss these things. I only can talk about what is my experience.


Furthermore it makes a huge difference, if using a film or a digital camera because of the thinner construction of the sensor chip...

cheers
c

 

[theno23]

The copy of a 28mm/2 Ultron I tried in a shop lacked contrast wide open, and was soft at 2.8 and 4. I guess that was probably beacuse of the focus shift, could also have been a poor sample. I would definitely try one before you buy it.

I got a 28 Elmarit ASPH instead. it's quite a bit more money, but a lot smaller and optically much better IMHO. Not everyone likes the high contrast though.

 

[Jim Evidon]

Thanks for the replies. I am aware of the lens adapter situation and I have always used the very wonderful ones made by John Milich located at the old Brooklyn Navy Yard in NY. They lack the notches and are are easier to code for my M8.
Like the rest of you, I expect some focus shift although I have a few lenses that exhibit none, but they are 35mm and longer. I was concerned over Sean Reid's review comments and the majority of the thread responses seems to be that the older LTM f1.9 Ultron is a better solution. I have the LTM f1.7 35mm Ultron and while not quite a sharp as my 35mm and 40mm Summicron's nor my 35mm f1.2 Nokton, the difference is hardly noticeable except to a pixel peeper.

Thanks.

 

[ZlatkoBatistich]

Focus Shift is never noticeable wide open, only stopped down.

That's correct. Focus shift, by definition, is not visible wide open -- assuming the lens is adjusted to be sharp wide open. It is a shift that occurs as the lens is stopped down. It is usually noticeable (if at all) about 2-3 stops down from wide open. If a lens is not sharp wide open, that is not due to focus shift, but rather due to being out of adjustment.

I guess an alternate possibility is when a lens is adjusted for accurate focus 2-3 stops down from wide open, and then focus shifts in the reverse direction (nearer) when used wide open. I understand the Zeiss ZM 50/1.5 Sonnar was initially made this way, but later optimized for wide open.

 

[250swb]

I had focus shift on my Ultron and my solution ultimately was to sell it and buy a 28mm Summicron.

The shift was so bad (except wide open) I had to focus bracket, or be in good enough light, and in front of an appropriate scene, to be able to make a photograph at f8 where the shift is compensated for by DOF. This takes all the spontaneity away from using the lens in all but a few circumstances. Other than that its a nice lens.

Steve

 

[filmfan]

Has anyone come up with some way of adjusting for the focus-shift?
I heard that with the Zeiss 50mm Sonnar-C, one can adjust for the focus-shift by focusing and then leaning in a few inches or so before shooting.

 

[Benjamin Marks]

Focus shift is, as far as I know, an inherent quality in a lens's design. Some manufacturers (Zeiss) will tweak a lens's focus for you to adjust where it focuses best wide open. They did this with the 50/1.5 Sonnar, which exhibits this behavior. The original batch of lenses came from the factory "optimized" for focus at 2.8. That is, the camera's indicated focus at f:2.8 was accurate. At f: 1.5 the lens was front focused slightly, and f:4 rear focused slightly and by 5.6 depth-of-focus covered the shift, so that it wasn't an issue. This was the original compromise around the design upon which Zeiss decided. Well, many folks wanted to use this lens wide open -- that's why they bought an f:1.5 lens -- and Zeiss reportedly adjusted the lens in relation to the mount so that it correctly focused at f:1.5 and then back-focused until f:8. They were not "removing" back-focus as an optical property of the lens, they were just changing where and how it kicked in as the lens was stopped down.

This quality exhibits itself as an unevenness in the zone of focus around the point of intended focus as a lens stops down. So your rangefinder tells you that you are focused on a mark, and at f:4 that particular lens focuses slightly in front of (or behind) the mark. Someone above in the thread said all lenses have it. That is possible, but it is only an issue when the point of best focus shifts beyond the depth-of-focus that your lens has at a particular f:stop and you cannot correct for it mechanically. You can learn your lens, though. I have two of the Sonnars mentioned above and I love 'em both. I just have learned to compensate in use for them. Yes, leaning in or out a little becomes second nature.

If you are shooting a 28mm lens at a subject 10 feet away and do not intend to crop much, it is unlikely that you will notice a lack of critical focus around the eyes, even in a large print. Our own Tom Abrahamsson has used a 28/2 Ultron successfully for years -- you can search RFF for the threads.

Ben Marks

Edit: On Dante Stella's site, he has a review of the original Hexar AF (fixed 35 2.0 lens) -- I think he states that the lens micro adjusted itself after the shutter release was tripped to account for focus-shift inherent in the lens' design at the aperture chosen by the user. Pretty cool trick, if true!

 

[Tom Niblick]

Looks like the consensus is - buy the CV 28 and either shoot wide open or stop down to 5.6 or just do not worry about it. That is the most economical decision. But Leicas are not about economy but rather getting the best possible results from a small, spartan kit.

I've looked at this lens and shot with the 28 Summicron, the 28 Elmarit ASPH and the 28 Elmarit type IV (46 mm filter) with my M8. I took dozens of test shots outside of a LA camera store and found the 28 Summicron to be perfect and the Elmarit type IV to be 95% perfect. The Elmarit ASPH was nice and small but I liked the files from the type IV better. The 28 CV was a little harsh for my taste - kinda chalk and soot. But I didn't notice any focus shift. And the price sure was tempting.

I was just about to pull the trigger on the 28 Elmarit type IV when I did a little adding and subtracting and found that, in this case, for $1,000 more (plus a few trade-ins) I could buy a M9 and just use my favorite lens, the 35 Summicron IV.

You have a tough decision so you might want to try a few lenses - if you can find them these days.

Tom