SE 18 vrs. CV15

[brentd]

Advertisement (gone after registration)

I'm wondering if some could share actual hands on experience of IQ of the SE18 versus the CV15?

 

Thanks - Brent

[Advertisement]

The Leica Q3 is available for pre-order at B&H Photo Video and Adorama

[wstotler]

Hi, Brent. (Welcome to the forum--if you haven't been welcomed already.)

 

I've shot extensively with both on my M8.

 

I started with a CV15 (it was my third lens, after the Summicron 35mm and 50mm) because I wanted an affordable super wide. The wideness was great, the size was tiny, and for the price the CV15 was super, but it was always softer and "stretchier" than I would have wanted.

 

The Super-Elmar + finder was expensive. . . . But the IQ that the SE18 delivers on a regular basis--edge to edge--is, frankly, incredible, even at f/3.8. In my experience, the quality has been at least two magnitudes of order better than the CV15.

 

You can compare IQ directly by browsing through shots here:

 

Super Elmar-M 18mm/3.8 - a set on Flickr

and

CV15 Heliar LTM f/4.5 - a set on Flickr

 

Thanks, and ask additional questions, if you like!

Will

[Guest EarlBurrellPhoto]

The 15 is effectively a 20 on the M8, whilst the 18 is effectively a 24. From my POV the difference in FOV trumps any comparison of their optical performance, though I know how much Leica folk enjoy to dwell on the latter.

[wstotler]

The 15 is effectively a 20 on the M8, whilst the 18 is effectively a 24. From my POV the difference in FOV trumps any comparison of their optical performance, though I know how much Leica folk enjoy to dwell on the latter.

 

Respectfully, Earl, it is OK to ask for a comparison like this even if focal lengths aren't identical.

 

The underlying question: "Do I buy a CV15 or do I suck it up and buy the SE18 + finder?" has a lot to do with IQ.

 

From that perspective, the question is meaningful.

 

* Do shots from the 18 look better than the 15? Yes. Better resolution. Cleaner. Cleaner. Better color. Even when pixel-peeping.

 

* Does the 18 vignette less than the 15? Yes. Vignetting on the 18 is minimal and in-practice invisible. I would often see vignetting (slight, but visible) with the CV15 that I would need to tinker with to remove--or crop in.

 

* If you crop in on the 15 to get an equivalent view to the 18 can you see the difference? Yes. Without pixel peeping. The 18 is much cleaner and has a better resolved image. It's not just sharpness, it's clarity and the way the depth is rendered.

 

* Is the 18 fully usable at 3.8? How about the 15 at 4.5? I have no worries about sharpness when shooting f/3.8 with the 18mm. I did tend to want to stop down the CV15 to a f/5.6, but usually f/8. This matters when shooting indoors.

 

* What about prints with both? I've had 20"x30" enlargements made from post-produced TIFF files. The SE18's prints, frankly, knocked my socks off. They were on par in terms of IQ with enlargements from my 35mm and 50mm Summicron. The on-screen clarity made a visible difference in final quality. The CV15's prints were OK but didn't have the same clarity as those shot with Leica glass.

 

To be clear, the CV15 is a great lens at an excellent price. It's small. It's well constructed. The IQ of the CV15 is good--the SE18 is just that much better across the board. The SE18 *is* missing a bit of the wideness of the CV15. But I have happily been doing without that bit of extra to get the overall gains the 18 has provided.

 

Cheers,

Will

 

BTW, this question has been asked before. *I* asked it and most responders in the thread were helpful, especially Andy Piper: http://www.l-camera-forum.com/leica-forum/leica-m8-forum/90474-comparison-new-18mm-f-3-8-a.html

[epand56]

Do shots from the 18 look better than the 15? Yes. Better resolution. Cleaner. Cleaner. Better color. Even when pixel-peeping.

 

Will, without any polemic intent, but this is not what comes out from the comparison of the two Flickr links you suggested. I'm not all that sure that the pictures of the SE 18 are so much better than those of the CV 15.

If you look at this link posted by a forum member in another thread, you'll notice how much the IQ of the CV 15 may be better than we can see on that Flickr set.

 

S O U L S OF T H E C i t y | Book Preview

 

The book is almost entirely made with the CV 15.

In my experience, the resolution of the CV 15 is quite amazing.

[wstotler]

Will, without any polemic intent, but this is not what comes out from the comparison of the two Flickr links you suggested. <snip> In my experience, the resolution of the CV 15 is quite amazing.

 

Enrico,

 

Thanks--no polemic intent taken.

 

The CV15 can make good, even excellent photos.

 

But you can see distortion, some fringing, pulling, and the like even in the Flickr photos that you will not see in the SE18 photos.

 

It's my fault for not providing some specific examples--so here are a few quickies.

 

Click "all sizes" to see photos larger. (Assuming you did this.)

 

This CV15 shot, if taken with the 18, would have had less fringe light on subjects and less "burn in" to its appearance:

Clock Tower Means Business on Flickr - Photo Sharing!

 

(I never liked the CV15's "burn in" that I'd get with that lens--I've never gotten that from the SE18.)

 

This CV15 shot, if taken with the 18, wouldn't have had the bendy concrete bridge pylon or the sky color shift:

Bridge Sky on Flickr - Photo Sharing!

 

This CV15 shot, if taken with the 18, wouldn't have had the pulled rocks (top) and harsh handling of details in the water (near bottom edge):

Faux Galaxy Sky on Flickr - Photo Sharing!

 

This CV15 shot, if taken with the 18, wouldn't have the blown out tree edges (where they meet the sky), nor bent the building edges in the background:

Dover 8 Percent PayCut Protest - Cigar Man on Flickr - Photo Sharing!

 

I've had a lot of CV15 photos come back with purple fringing at edges of objects--no examples of that immediately available--the SE18 has never done that to me. (I think that's called CA?)

 

And so on.

 

I'd have to shoot direct side-by-side comparisons to make a more solid case, I suppose. I was thinking of doing that this afternoon but didn't have time. Maybe in the coming week.

 

Thanks!

Will

[adan]

Advertisement (gone after registration)

In my M8 days I used the 15 c/v from the beginning. In fact the first shot I ever made with a "beta" M8 was with the 15, to check for vignetting and internal sensor reflections (and it passed with flying colors).

 

I was also an early, brief, adopter of the 18mm SEM last summer. To be fair (and to agree with Earl) the main reason I returned the 18 and stuck with the 15 was FoV. I like a 20/21 view of the world and a "24" - no matter how good - just feels like running on a flat tire by comparison.

 

I also preferred the color rendition of the 15, just as I generally prefer the color of the pre-Solms Canadian lens designs, which the 15 matches fairly well. The 18 has the same "Contaxy" reddish tendency as most of the other ASPH M lenses.

 

I hoped the extra stop of the 18 would redeem its narrower view, but ultimately f/3.8 still didn't cut it for me (I consider an f/2.8 to be a moderate aperture, and only f/2 or faster to be fast). And given I was stuck with a slow lens in either case, the smaller size of the 15 was something I didn't want to give up.

 

Ultimately the only way I found to improve on the c/v15+M8 combo was to get an M9, where I could shoot my "real" Mandler 21 @ f/2.8.

[epand56]

Will, thanks for the examples. I think the real problem, here, aside of the beautiful FOV of the CV 15 on the M8, is the difference in price that does not justify the small (IMO) improvement of the SE 18 over its LESS expensive little cousin.

Besides, most of the blowing highlights depends on how the CV 15 is used. And, again, the slightly better sharpness of the SE 18 is not worth the price 8 times heavier.

But, you know, I'm not really a Wide-Angle guy, so my opinion is based on my kind of photography.

[Guest EarlBurrellPhoto]

Respectfully, Earl, it is OK to ask for a comparison like this even if focal lengths aren't identical.

 

The underlying question: "Do I buy a CV15 or do I suck it up and buy the SE18 + finder?" has a lot to do with IQ.

 

From that perspective, the question is meaningful.

 

Ok, in that case, I vote for the 90 APO-ASPH vs the 15 CV

[wstotler]

Comparison tests posted:

 

CV15 and SE18: Indoors 1 on Flickr - Photo Sharing!

CV15 and SE18: Indoors 2 on Flickr - Photo Sharing!

CV15 and SE18: Indoors 3 on Flickr - Photo Sharing!

CV15 and SE18: Outdoors 1 on Flickr - Photo Sharing!

CV15 and SE18: Outdoors 2 on Flickr - Photo Sharing!

CV15 and SE18: Outdoors 3 on Flickr - Photo Sharing!

 

Click the "View full size here" link below any photo to see it 100% size.

 

Thanks,

Will

[Guest mc_k]

Thanks for these, they're very helpful. I'm not familiar with wide lenses, so this is a naive question, but in the first test (bookcase at 2m) why did you focus the 15 at infinity instead of 2m by scale? Thanks

[wstotler]

why did you focus the 15 at infinity instead of 2m by scale? Thanks

 

NP. The CV15's infinity is very close. Marked scale shows 4ft, then a little further 2m, then a smidge more to the infinity mark. Infinity in actual practice for the CV15 on the M8 starts at around 5 feet (at f/4.5). The "2m" (6 1/2 feet) listed on the JPGs isn't completely accurate--it's actually a bit more than that at around 2.3m (7.5 feet). E.g., I made sure I had enough distance from the bookcases to ensure the DOF included the bookcases with infinity focus.

 

Thanks,

Will

[adan]

As a user of the c/v 15 for 10 years - shooting something at 2 meters with the focus set to infinity (or vice versa) will produce a noticeable loss of sharpness. The DOF markings are based on viewing an 8"x10" print, not pixels at 100% on a computer screen.

 

If you think it is reasonable to use infinity focus for subjects at 2 meters - fine. But to be fair, do the same for your 18 SEM samples also. I think you will see a marked fall-off in quality from that lens, as well.

 

Just as Erwin Puts did when he tested "hyperfocal" focusing with the 18mm: SEM18, part 2

 

Even at 5 meters there was degradation compared to "really" focusing the lens with the RF.

[uptong]

First off I do not currently own the CV 15 but have been researching this little gem prior to picking one up. In course of my travels around various articles I happened on the one by Steve Huff see: here

 

He makes reference to the crop factor of the M8 having an influence on the setting of infinity mark with 15 he writes ........ "With the crop factor of the M8, the lens can no longer be set on F8 and infinity as your shots will not be as crisp as they should be. After some research and trial and error with about 200 shots, I found if you set the lens to F5.6 and set the infinity mark on the barrel to F4.5 you will then have a Point and Shoot M8. Or F8 and F5.6"......he backs up his findings with samples.

 

Now I am not saying he is right or wrong in this, I am simply referring to an article found on the net, it is interesting nevertheless so the point is has anyone else who uses this lens found this to hold true and would this have a bearing on the op's test findings.

 

In any event it will make little or no difference to my decision to get one of these little gems the FOV and the bang for the bucks is simply a no brainer to pass over for my intended use

[wstotler]

If you think it is reasonable to use infinity focus for subjects at 2 meters - fine. Even at 5 meters there was degradation compared to "really" focusing the lens with the RF.

 

Thanks. That's the first time I've heard that the CV15 isn't focused at infinity at a little more than 5 to 6 feet out, but rather at 15 feet! It's commonly said that infinity focus begins at 5+. Hear your point about the 8x10 vs. on-screen. I think some near-distance tests are in order for validation.

 

I've marked the comments on the indoor test shot photos at Flickr to reflect that more testing is needed to validate the findings. The outdoor photos should not be affected.

 

Thanks!

Will

[Guest mc_k]

I would redo the same test with the 18 RF focused and the 15 scale focused at 2m. If you find any difference, you might then bracket in the vicinity of the 2m point and take the sharpest trial. Looking at the Hunter Thompson titles that are pretty much in the center of the frame, the 15 took a licking throughout the range.

 

This is a distance at which I would use the lenses, so thank you for posting the tests.

[wstotler]

Andy, thanks for your patience and sharing your experience. More on that below.

 

I would redo the same test with the 18 RF focused and the 15 scale focused at 2m. This is a distance at which I would use the lenses, so thank you for posting the tests.

 

Thanks. I was testing before and when you were responding, largely because Andy debunked the "5ft. infinity" thing above and laid out why. So, there was an obligation to go back in and test it out. (I respect Andy's opinion.) Go have a look now?

 

 

Shooting something at 2 meters with the focus set to infinity (or vice versa) will produce a noticeable loss of sharpness.

 

I ran a series of focus-bracketed tests with the CV15. The sharpest focus was found about 2/5ths of the way past the 2m mark, when twisting toward the infinity mark. This is right on the money for focus.

 

(Method: I shot a full set at 2m * * * * * infinity, where each star represents a shot set. Or, roughly the width of the painted dot used to mark the focus next to the scale. And then I examined each set in post, at all apertures, to determine the best set. The 2nd and 3rd sets were very similar, but the 2nd was slightly sharper, so I used that one. The 1st was OK but not great--however, the 4th and 5th showed degraded image quality, leading to the final position, infinity.)

 

Andy--you were absolutely right about infinity focus for the CV15. The "infinity begins at 5ft." thing is simply untrue. I'll debunk that one at every opportunity when I see it.

 

OK. Revisions are posted for these two tests:

CV15 and SE18: Indoors 1 on Flickr - Photo Sharing!

(Can't redo number 2 because the stroller was moved overnight.)

CV15 and SE18: Indoors 3 on Flickr - Photo Sharing!

 

Sorry for the fouled testing based on a faulty assumption--these tests should clear that up.

 

Thanks,

Will

 

P.S. That's it for me. More than enough info posted on this question now. And The Prisoner remake starts tonight on AMC at 8. So, gearing up for that.

[adan]

Ok, I'll buy that interior re-do as a fair comparison.

 

c/v 15 has lots of resolution (as does the 18), but gets a tad muddier in the middle row of books (art nouveau flower binding, and the gold type of the books either side of it are duller contrast). Both lenses start to lose it as diffraction kicks in @ f/16-22, with the 18 holding up just a bit further.

[Advertisement]

Hallo,

Look here: Leica M

[Guest mc_k]

I think saying "infinity begins at 15 ft." is still a little misleading. It's only a plane out there at the front of the bookcase that's in maximum focus. Everything else is focused a little behind or a little ahead of the sensor. It will still look reasonably focused if it's in the depth of field. This is where the original experiment went a little awry. I think this is why a couple of your bracketings were sharper than the others, and why any test of sharpness should use bracketing. If you use a lens with a shallow depth of field at this distance, and run a target along a rail at 1" intervals, you will see a couple of the shots that "pop" more than the others. The plane of maximum focus is somewhere in this neighborhood.

[Guest mc_k]

Thank you for all the testing! And also for the samples, which I had already run into on Flickr. This should be really helpful for someone who is shopping for something around this focal length (like me). The two Zeiss lenses are also interesting.