What lens characteristics are important to you?

[Dogman]

Something got me to thinking recently about what optical characteristics I value most and least in a lens. I'm sure everyone has different priorities so I thought it would be interesting to hear different thoughts. Doesn't matter if you shoot digital or film or both...we all uses lenses of some type.

Of those quantifiable clinical characteristics found on review websites, I guess I rank "resolution" or "sharpness" as most important to me. And, yes, I know resolution and sharpness are not exactly the same thing. But they're close enough for government work. As long as the picture looks sharp with good fine detail, however the lens maker does it, I'm down with it. I want a lens that is sharp to start off with--I know I'm capable of making unsharp photos (I've done it often enough) but I want a lens that gives me a head start on being sharp. But clinical sharpness can be dull unless there's some spices in the recipe.

"Distortion" would rank second for me. Again, whether the lens maker does it with software or optically is not my concern. I just hate using a lens that makes straight lines a lot less than straight.

"Aberrations" is pretty important to me. But only if so excessive you can't help but notice them. Software pretty well controls these today. Could be that some aberrations add a little spice for flavor so maybe it's not a good thing to be aberration-free.

I guess I would rank "flaring" next although we're getting into the less important stuff. Most lenses have this so well controlled these days it's not an issue at all.

All told, I suppose I value the "look" a lens imparts to a picture. How the characteristics come together to make photos done with it kinda sing.

The things that are NOT important to me include "bokeh". It's become a trendy topic among lens testers. I for one just find it tedious. Some of the "bad bokeh" identified by some websites look better than the "good bokeh" they go ga-ga over. Lack of "vignetting" is so unimportant to me I always add a little in Lightroom, just like I used to burn down the edges of my prints in the darkroom.

I've left out some items like AF speed, build quality, maximum aperture and image stabilization, etc. I'm more concerned with how the picture looks than the mechanical/electronic means that gets you there. I'm sure I've left out some important other things but, hopefully, you get the idea.

 

[Sumarongi]

^^ subscribed

 

[sepiareverb]

In no particular order:

I like to have the capability of shooting a flat field and having it be in focus all across the frame.

I like lenses that illuminate evenly, so little vignetting. It is easy to add a vignette in the darkroom, but a bear to remove.

I also want a lens that can deliver crisp detail at large print sizes, which RF lenses certainly are better at than SLR ones. A generality I know, but one I have seen again and again.

An OOF rendering that is pleasing to the eye. I don't have a set definition of this, but have had some lenses that were just too "mushy" some that didn't seem to really soften up enough.

As with most things, it is easier to reduce quality than it is to improve quality, so I tend to go for the best lenses I can find in most cases. That said, I have an old 3.5cm Elmar and a Summitar 50 that I love even if they don't tick the above boxes.

 

[retinax]

Mostly agree with you, OP, and would add: Price. I'm fairly poor.
As for the point of bokeh, I do notice pleasant or unpleasant bokeh sometimes, but agree that the internet is full of nonsense about it and it's of lesser importance to me, too.
Ergonomics is another important point, if we're not talking strictly optics, speed as well to some degree. On SLRs I value faster glass for the more precise focusing it provides stopped down.

 

[willie_901]

I abhor longitudinal chromatic aberration. One reason I sold all my Nikon DSLR gear was all my Nikkor prime lenses exhibited high levels of LCA.

With a digital image first-order barrel/pin cushion distortions are trivial to correct. Higher-order distortion correction is typically remedied by proprietary in-lens firmware. This is not an option for film. I suppose somewhere there are methods to digitally minimize higher order corrections in scanned film images.

Next on my list is coma. At some point coma becomes a distraction. I'm sure we all have different thresholds.

Finally I don't like out-of-focus rendering where circular objects have polygon shapes similar to aperture opening shapes.

For some of my previous work ultra-wide angle lenses with high levels of flare and ghosting artifact levels in contré-jour scenes was a show stopper.

Lastly, I prefer lenses with low levels of field curvature.

 

[jamin-b]

Good thread - I have given this a lot of thought. I find I really value close focusing ability (and resent lenses with minimum focus of 1m or more), appreciate compactness/ lightness and lenses with good handling and special character, either where sharpness / microcontrast is so fine as to become a defining characteristic (such as Zeiss 50mm Planar or the ZM 28mm 2.8 and 35mm 2.8) or because the lens just renders beautifully (for instance, Pentax 77mm Limited, Nikkor O 35mm f/2 or Nikkor 25-50mm zoom).
I don't like distortion but it's never a decisive matter, couldn't care less about fall-off / vignetting and actually like how some of my older lenses flare.

 

[bayernfan]

The big one for me is a generally pleasing rendition of the scene/subject, which is more often that not a consequence of the optical formula. Second is a gentle contrast which gives way to nice long tonal scale. Finally, a lack of distortion. If these three are satisfied, I'm probably giving the lens serious consideration unless the build quality, size, etc is a problem.

The above translates to lenses like: 50/2 Summicron V1, 75/3.5 Rolleiflex Tessar, 35/2.8 Summaron

 

[Pioneer]

Reasonably sharp across the field without stopping down too much.

Decent contrast.

Accurate color rendition, prefer a bit warmer then cooler.

Low distortion.

Low vignetting.

Resists flare.

Minimal or no color fringing.

Neutral bokeh.

This sounds a lot like my little 50mm Elmar. Maybe that is why I like it so much.

 

[Ko.Fe.]

Sharp, no flaring and not flat on BW film. Short focus throw, tab and compactness.
The only one I have with all of it is Summarit-M 35 2.5.

 

[aizan]

it depends on what i'm doing at that time. how much i even care about it depends on the application.

 

[mooge]

Kind of interesting question - I was thinking about that some time ago and the things that are most important to me aren't usually the top items in lens tests.

1. Ergonomics. If it has a long focus throw (like 180° for a 35mm), I'm not super interested. Same goes with lenses (50mm or less, at least) with a minimum focus 1m or longer.

2. Lens speed. I used to shoot slides pretty often.

3. Price. Well, sorta. Around $1000 is where I'd draw the line, more or less.

4. Distortion, I guess?


The usual stuff - sharpness, contrast, whatever - I figure there aren't many stinkers out there for the cameras I have so it's kind of nitpicking when it comes to that stuff. Rendering I kind of get, but it's gotta be really gross (i.e. thambar) before I'm turned off.

 

[Ccoppola82]

Depends what I'm doing really. Some days when my focus is purely photography, size doesn't matter, but when I'm just carrying my camera around daily I prefer to keep it small. That's my first determining factor. As to rendering, for people and street stuff, I like softer contrast, longer tonal range and don't mind the "playful imperfections" a lens exhibits. For me, the lenses of the 50s-70s hit this balance perfectly with my lenses of choice typically being a 50mm Summicron v1 or v2 rigid. I just grab either and go. I also almost always have my Summaron 35 2.8 with me as well. For me these are perfect. For landscape and serious stuff, the hasselblad comes out to play.

 

[PhotoGog]

In order:

1. Microcontrast.

2. Size (for instance, CV 35/2.5 M mount or CV 40/2 F mount are sublime ergonomically).

3. Sharpness in the corners as I use the frame edges a lot in composition.

4. Smooth fall off of OOF areas (as opposed to simply bokeh).

5. Build quality. It has absolutely got to be all metal barrels (the great let down of FD lenses is their plasticky bodies despite quality optics). The only exception I make are my kit of Pentax SMC 67 lenses because of no other choice given may of them are lighter or better optically than their metal Takumar versions - and weight counts for a lot with the 67!

 

[NickTrop]

What matters:

1. Focal length
2. Cost
3. Speed
4. Optimal resolution/sharpness
5. Autofocus accuracy/speed
6. Flare resistance
7. Focusing distance
8. Size/weight
9. Build quality
10. Weather resistance
11. Dust resistance
12. Whether you include a lens hood if purchased new. Yes please. And can you throw in a cheap bag while you're at it?
13. This should be higher on the list, mayber in the top 3 but I thought of it later -- quality control, sample variation, decentering, etc.


What doesn't matter:

1. "Bokeh characterists" (nobody notices, cares, doesn't matter... You just want to isolate the subject. Nobody notices/cares if bokeh balls are circular or hexagonal. Is given far too much attention in lens evaluations)

2. Corner softness wide open (Shooting wide open? Most likely you've got an isolated centered subject and corners are dark and out of focus...)

3. Pincushion/Barrel distortion (Easily corrected or corrected in-camera)

4. LoCA (never bothers me, easily corrected or eliminated in-camera)

5. Lateral CA

6. Contrastiness -- (easily added in post)

7. Color rendition -- (usually altered in post or in-camera. Doesn't matter anymore...)

8. Diffraction at small apertures

9. Microcontrast (not even sure this exists)

10. Autofocus noise (Seriously? None are really all that loud...)

11. Coating. (Outdated marketing shtick started by Pentax in the 60's -- "Super-de-duper Muilticoated Takumar!). It's 2018, all lenses are coated.

12. Whether a lens has aspherical elements or ED glass. I'm not a lens designer and don't care. Some (most) of my favorite lenses had nothing "exotic" in them. Do what you have to do to make a nice lens. Marketeers? Stop your silliness.

13. How many aperture blades or if they're "rounded".

14. VR/IS on non-telephoto lenses. They're throwing VR on everything these days, aren't they? Telephotos? Sure. A prime? A wide zoom? I'll take it as a standard feature but won't pay more for it. It's not a deal breaker.

 

[Sumarongi]

it depends on what i'm doing at that time. how much i even care about it depends on the application.

Exactly.

To name but a few things:

Criteria like zero field curvature, or zero distortion, only count when I'm making reproductions of flat objects (e.g., copperplate engravings).

On the street, distortion or field curvature don't matter at all, IMHO.

 

[LukasB]

Compactness and usability are my main concerns. Ideally I'd like a Camera the size of a P+S, with a 35 1.4. I'd also like it to not become a brick very fast in the event of damage/time. For instance, I rather like the Contax T3 - very expensive. Becomes a very, very expensive Paperweight. That's not for me. Lenses, however - I like older rendering Lenses. To me, that's what Photography looks like. I don't mind vignetting, nor do I mind Lenses not being perfectly sharp. Ideally I'd like distortion to be as low as possible. This is the only gripe that I have with the CV 35/1.4. Otherwise, aside from being a little big - it's perfect.

 

[RichC]

I take a slightly different approach.

First, there’s certain properties that any lens must have before I consider it remotely useful as a photographic tool. These aren’t in any order - they’re compulsory and must meet by minimum expectations. They are, in no particular order, sufficiently

• sharp into the corners
• low distortion
• low flare
• low aberrations (chromatic, etc.)
• good build quality and ergonomics
• smooth bokeh.

I don’t consider these “characteristics” but essentials. Without them, any lens is useless as a photographic tool unless you specifically want flare or blur - like using a cheap screwdriver that ruins screws and possibly injures you!

As an aside, I use only high-MP cameras like the Nikon D800E (36 MP) and, now, the Sony A7R II (42 MP), so lenses need to be pretty damn good as these cameras will magnify any lens weaknesses!

So, what are my preferences for optical characteristics - which is what the OP is interested in? Actually, there’s just two, though they’re related:

• low contrast and muted colour.

I suspect both are technically faults resulting from poorly controlled flare. Advances in lens coatings and optical design through the use of computers have minimised these problems - resulting in today’s lenses producing high contrast and saturation.

Although today’s lenses are technically better than their predecessors, I dislike the images they create. I find them harsh and garish (especially when used with digital cameras), and the look “clinical” - every subject is recorded accurately in high fidelity and looks as if it came off some production line.

The older lenses I prefer - mostly from the 1970s and 1980s, a few exceptional ones from the 1960s - with their muted tonality and colour produce photographs that convey more emotion, that allow a greater connection between the viewer and the subject, than modern lenses, which I feel create more of a barrier to the viewer with their more “technically accurate” rendition.

A previous poster mentioned the Elmar 50mm. If they mean the f2.8 made in the 1950s and 1960s, I concur. This exemplifies all the qualities I want from a lens. Most of my lenses are 1970s-1980s manual-focus Nikon AI/AI-S - the best of which also meet my criteria.

 

[narsuitus]

Resolution
Contrast
Focal length(s)
Lens speed (maximum lens aperture)
Function (What is the lens going to do for me?)
Compatibility with camera body
Color (tints, shifts, saturation)
Type (prime, zoom, mirror, macro, portrait, shift, etc.)
Construction/Workmanship
Material
Price/Value
Features (auto vs. manual, IS or VR, weather resistance, lens coating, filter size)
Reputation/History of the lens and/or the manufacturer
Optical defects (pin cushioning, barreling, vignetting, and chromatic aberration)
Ability to handle light reflections on lens surfaces (flare)
Bokeh
Compatibility with my other lenses
Focusing speed
Feel/Handling/Ergonomics
Size/Weight
Diaphragm design and construction
Coverage (ability to handle shifts, tilts, swings, slides)
Lens board size and hole (large format)
Shutter design and construction (large format)

 

[ForestCap]

Price and compactness.


btw: Can someone explain what is "micro contrast" to me? I see the term a lot but can't find a comprehensive definition of it anywhere on the net, in all three languages I speak.

 

[michaelwj]

Price and compactness.


btw: Can someone explain what is "micro contrast" to me? I see the term a lot but can't find a comprehensive definition of it anywhere on the net, in all three languages I speak.

Global contrast is the maximum difference between the blackest and whitest points in an image
Micro contrast is the maximum difference between adjacent “pixels”. It’s like the unsharp mask in photoshop, increasing the contrast at an edge. I don’t like the term, it reeks of baloney.