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15mm vs. 21mm vs. 25mm
Old 03-06-2008   #1
corazon
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15mm vs. 21mm vs. 25mm

1) Hey I am just wondering if anyone has sample tests shots of the same subject from the same viewpoint for these three focal lengths.

I have a 35/2 that I love and want wider still.

2) I suppose I could/should go into a store that sells CV rangefinder lenses to test them out. I just thought of that now and am wondering.. any such places in the Toronto-Ottawa-Montreal region?

the 15mm is alluring, but I'm not sure how practical or how much use I could get out of it compared to the other two focal lengths.

I'm worried 24mm/25mm is too close to 28mm.

3) Does 21mm produce much vignetting (I know this is more a question of brand/price)? 3a) What about rectilinear distortion?
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Old 03-06-2008   #2
nobbylon
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I've got a 15 and hardly ever use it. I'd consider it a specialised lens for the odd situation you really just can't get everything in the picture. I myself also have a 35 and am just debating 21 or 25. I have a 24 ziuko for the OM though so i'm pretty sure it's going to be a 21. I will keep the 15 though just for that once in a while.
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Old 03-06-2008   #3
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if there's a store in town that sells cv products, you might be lucky and they had all the viewfinders..?? or, leica or seizz for that matter.
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Old 03-06-2008   #4
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Unfortunately, despite much well meaning advise, you will never really know until you live with each focal length for a while and decide for yourself if it fits your style. Looking at other people's photos of different focal lengths never helped me, since you don't get a sense of how close you need to be to the subject to get the look and framing that you want.

Personally, I would look for a cheap, used beater lens at one focal length - don't worry about the quality of the lens, just concentrate on the framing. If you like it, then trade up to a better quality lens. If not, sell it and and move on to the next focal length. In the end, I think this is probably the most cost effective way to find the lengths that work for you...
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Old 03-07-2008   #5
Sonnar2
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My first camera with a Leica screwmount lens was the rangefinderless Bessa-L with the 15/4.5 back when it was quite new, 1999.

I took a lot nice landscape pictures with it, even it took some learning for me. You can manage to avoid "extreme" pictures if you observe a few things. With a 15mm the area of view is about 11x the size of a 50mm. Keep this in mind before ordering 3x4" prints....

Of course I bought this camera because it was the only smallsize, lowcost wideangle combo available then. 21mm is a bit easier than 15mm. Both CV lenses are excellent. But the 15mm is a class of it's own in terms of sharpness and insensibility to flare. It was THIS lens who made Cosina be respected for it's high grade glass. ZEISS and LEICA could be proud to have it, but they hadn't made it. COSINA did.

The 25/4 is also great but I found it's a bit too close to 35mm and I sold the two versions I had. But maybe it's fine to you. In the meantime I gained another (Canon 25/3.5) but more for collection reasons, also it is a great, small sized lens to use. The 21mm has about 2x the picture size of a 35mm and is a great addition. It takes nearly no space in the bag.

cheers,

Last edited by Sonnar2 : 03-07-2008 at 05:11.
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Old 03-07-2008   #6
oscroft
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Sorry I don't have any comparison shots, but I have had all three lenses in their CV screw-thread form. (The only one I don't have now is the 25, because I sold it in order to buy the coupled version - I haven't got round to that yet, but I will do so).

The 15 (which is the first CV lens I got) is a lot of fun when I use it, but that's hardly ever. It's just too wide (way too wide, not just a bit too wide) for any kind of regular use - I don't carry it with me, I just occasionally go out with it specifically to try some super-wide shots (because I'm a bit of a super-wide freak from time to time).

The 25. I think it is significantly wider than a 28 - enough to make me want both (I have a CV 28/3.5, which is possibly my favourite lens ever, but I will still get a new 25). But some would certainly think they're too close together to want both. I wouldn't carry a 28 and 25 together, but I do tend to think and see differently depending on which one I have with me.

Now the 21 - that's a real wideangle lens. I use my 21 a lot, which is partly because I do a lot of shooting in cramped locations in places like Bangkok, but partly because I like to get in close and fill the foreground. Stopped down, I don't get any significant vignetting problems.

If I didn't have these three lenses, which one would I buy first (leaving aside the fact that I actually bought the 15 first - because most people would consider that madness)? If the widest lens I already had was a 35, I think I'd get a 25 next. But if I had a 28, I'd go for the 21.

But that's just me, and we're all very different - as others have said, you need to get a feel for them and try them yourself.
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Old 03-07-2008   #7
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My previous lens line-up was:

CV50f2.5, CV35f2.5, CV25f4.

I wanted a wider focal length and I wanted a faster lens, so now it is:

CV50f2.5, CV40f1.4, Summaron35f3.5, Canon28f3.5, CV21f4
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Old 03-07-2008   #8
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I have a 21, 25, 28 and 35.

The 28 is a big leap from a 35 for me. 35 is my normal lens. When taking shots of people at an event and or on the street it's easy for bystanders to be in the way. Still, it doesn't distort too much for me and is easily controlled. It's a must have for a Leica if you don't want to use a viewfinder, but at the same time I always feel that I am getting more than I see through the camera. I suppose well stopped down it can be used as a hyperfocal lens. A 28 is still not wide enough for architecture. It's a funny kind of place in being too wide and not wide enough all at the same time. A 28 is as wide as you can go if your are trying to keep your shadow out of the picture so in the end its a necessary lens for the street.

I see very little difference between the 21 and 25. You are now officially 'wide'. distortion is a balancing act but the wrap around fish eye look is not a problem if you have a decent lens. These are too wide for landscape with 35mm if detail is an issue. They're too wide for the back yard, but just right for the Grand Canyon. They're great for indoor shots, and groups of people. Your shadow will always be in the shot if you are shooting up close.

18 is the real superwide verging on the fish eye. I suppose if you had a limited budget the choice would be 18, 21 or 25, and 35.
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Old 03-07-2008   #9
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Quote:
18 is the real superwide verging on the fish eye
"Fish eye" isn't actually determined by focal length - a fish eye lens is a wide angle lens that does not have rectilinear correction, so some 18mm (and wider) lenses are fish eye and some are not. For example, the CV 15mm and 12mm lenses are not fish eye lenses - they are rectilinear wide angle lenses.
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Old 03-07-2008   #10
BillBingham2
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I love the 15mm and wish CV would come out with another round of high quality Nikon F to S adapters so I could get one for my S3. My main carry kit in the Leica M space was 15/40/105 with a 25 on a Bessa L. I owned a Leica 21 and never really liked it, it was just too wide or not wide enough. I love the 25/4 CV and it and a 35/2.5 make up my wide angles for my S3. I still have a 15 in LTM because it is such a fun lens to have. There are lots of fun shots that the 15 gives you that a 21 will not.

Everyone is different and I would suggest that you could recoup most of your investment in any of the lenses you get if you do not like them. I think a 25/4 and 15/4.5 would be a great combo to add to your 35. If I were to buy a single lens to complement the 35 I think it would be the 15, but that is me.

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Old 03-08-2008   #11
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I somehow got logged out, so my post didn't stick.

Basically, I said that: I've got a 28mm, but it's on my Elan 7 and even then I wanted wider still. So I think I will head out to Bank St. and try out some SLR lenses for the focal lengths. I certainly don't want to be caught in my own shadow with the 21mm, but I'd watch out for that and a bubble level of course to keep things straight. The 15mm is calling me, but my budget is sternly telling me, buy something more than a 'sometimes' lens til it makes more sense. So it's either the 24mm or the 21mm. I'll check out Vistek maybe (I am in Camera Trading Co. too often having never spent a penny there) to give my mind more to work with.

Thanks for the commentary guys n' gals.. though I may have been the only gal in here
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Old 03-08-2008   #12
corazon
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I know the 15mm really can do that Shot you know.. that otherwise you just couldn't get with anything else. I saw just that shot the other night by an overpass and it got my thinking 15mm.. you're a lovely thing you are.

I just had to mention it because those shots that just feel as if they go on forever.. oooh are they ever breathtaking.
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Old 03-10-2008   #13
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I use 15, 21, 24, 28, 35, and 40--in short, everything but a 25. My only reason for the 40 is to experiment with getting better frameline accuracy with the M6. With regard to the others, I fin d the differences between them great enough to use them all.

Although a 25 or 24 may seem, for some users, too close to a 35, I find a world of difference between them. A 25 actually covers twice the area of the 35. Not twice the linear width or height, of course; but twice the subject area. To me, both in theory and in practice, that is quite a difference.

Even a 28 is different enough from a 35 to make it worth having both (for me--someone who wants to travel lighter or be more "minimalist" in approach will feel differently. For me, the minimalist approach would be 24-35-50--and possibly a 90 or a 75.)

As to the 15, I never felt the need until I bought a DSLR. Then I needed 15 to get a 22.5 equivalent. I you go for a 15 with film, be prepared for a very, very different perspective!

A problem with extremely wide lenses is that they often take in too much. With a 21, I find that I am running into telephone poles, no smoking signs, etc. On a mountain top, I even had to switch from 21 to 24 to avoid running into a remote weather station shack!

I would suggest a 25 as a sensible addition to your 35. It is wide, but not so wide as to create as many problems as it solves. Or if you want to add a wide angle lens that will not challenge you to a whole new learning curve, even a 28 is a very useful addition to a 35. The 28 opens up space--creates a feeling of spaciousness--more so than a 35.
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Old 03-10-2008   #14
Dektol Dan
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Quote:
Originally Posted by oscroft
"Fish eye" isn't actually determined by focal length - a fish eye lens is a wide angle lens that does not have rectilinear correction, so some 18mm (and wider) lenses are fish eye and some are not. For example, the CV 15mm and 12mm lenses are not fish eye lenses - they are rectilinear wide angle lenses.
I stand corrected.
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Old 03-10-2008   #15
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I used a 15mm and 40mm combo for awhile (the 40mm being 60mm on 6x45). The combination worked well for me; there were times certainly when the 15mm was overkill, but it is something you have to learn to use effectively. There is no reason your 15mm pics need to look cartoony; that happens as a result of intentionally placing nearby objects off of center or decentering the horizon. So either a tool or just sloppy shooting.
On another note, I saved my money and scrounged the world for a medium format architecture. Finally, I bought a Brooks Veriwide, so scaled up Bessa L with 21mm. There have been SO many times it just wasn't wide enough to get the job done....
So I guess it all depends on your intentions, style, patience, and expectations. Certainly wide lenses are not 'normal' ones and how much use you'd get from which one is very personal.
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Old 03-10-2008   #16
peterc
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Quote:
Originally Posted by corazon
any such places in the Toronto-Ottawa-Montreal region?
Downtown Camera in Toronto has most of the CV wides in stock.
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Old 04-29-2008   #17
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Here is a awesome link for determining what focal length to choose.

http://lens-reviews.com/Technical-Ta...tion-Tool.html

After looking at it, it would be 24/25mm or a 21mm. As I want a cheap lens, CV, I will choose the 21mm due to being rangefinder coupled (LTM for cheaper price).
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