Mastering the Art of Lens Testing – Wrapping up

All right ! You have now completed this first course on lens evaluation in the field. Thank you for being with us all this way. We want to congratulate you for reading through this information and hope that you have derived as much pleasure from the experience as we did writing it.

If I had to recap in one sentence it would be to say that all lenses come with a combination of aberrations that define their rendering and usefulness for any particular type of photographic endeavour.



An almost perfect lens. But can you see the cats eyes ?


As photographers, we need to understand it’s impossible to create lenses without these aberrations. All the designers do is reduce as many as they can to the level they find tolerable for the intended application.


Full of aberrations and full of charm

Exhausted. Full of aberrations and full of charm


Some lenses are generalists (in particular zoom lenses that come bundled with medium range cameras) whereas others are highly specialised designs. A copy lens is design to afford a very flat field and low astigmatism and will often do this at the expense of other traits that portrait photographers might find intolerable.

On the contrary, a 85/1.4 lens intended specifically for portrait photographers was recently launched. It’s a very recent design benefitting from all the expertise of the brand and all the high-power techno-wizzardry at their disposal. And yet, this lens uses only spherical lenses. This gives you the slight softness at full aperture that some users would be displeased with, along with fabulous bokeh, both highly desirable for a portrait photographer.



The Zeiss C-Sonnar 1.5/50 ZM. Terrible for some, over my dead body for others.


So, at the end of the day, focus on your specific tastes and needs alone when you decide to buy a lens.

Or a camera for that matter.

A few years ago, my wonderful wife offered me a year of weekly wine-tasting lessons from a local cellar-master. Week after week, we analysed colour to estimate age and terroir. We trained our sense of smell one sent at a time, then with a combination of two in the glass then with three so as to familiarise ourselves with primary, secondary and tertiary aromas. We watched legs grow to guess at alcohol. We tasted great cheap wines and terrible expensive wines, then vice versa.



Decanters (c) Paul Perton


It was a fascinating journey but the greatest part was the end goal. The expert training us hadn’t done so to make us discover the origin of wines with a blindfold. His goal was far more intelligent and beneficial to us. He had given us an advanced education so we would be able to analyse what we like in a new wine (for example in a restaurant or abroad) and be able to describe it to a wine merchant back home to find something similar for ourselves.

This course aims at empowering you in the same way with photographic equipment. Because …



Yes, it is all about gear



How many times have you heard the platitude “it’s not about gear, it’s about the photographer”. That’s the same as “content is king” in marketing. Utter and absolute nonsense only meant to dumb things down to a level where easy recipes can be sold to a naive buyer.




But the fact is gear matters tremendously ! Here are two examples :

(1) There are fun videos on YouTube where pro photographers are given low quality cameras for an afternoon. The results speak for themselves. The photographs these highly trained and creative photographers produce wouldn’t make it pas round 1 of an amateur photo competition.

(2) Recently, a friend of mine heard that I was reviewing a very high-end wide-angle for a prestigious brand. He owned a copy of that lens and told me he was unsatisfied with a very specific aspect of it : strong field curvature on close focus. As a landscape photographer who always uses a foreground object in wide photographs, all his backgrounds were sharp in the center and very blurred on the edges, whatever the aperture. Obviously unacceptable for his use and yet, the majority of users of this $3,000 lens love it.


Plus, buying gear is just plain fun. A good acquisition provides a pleasure that lasts for years or decades. Great gear (which can be cheap as dirt !) plays an important part in our hobbyist lives!

It is all about gear. And how it matches your needs.




Truck, Florence, Az – 3D that only a very high quality lens can provide


So what’s the next step ?

Well, first, recognising that testing lenses is not the correct way of choosing 😉 Yeah, I know, I’ve been pestering you about if for 10 messages, but just stay with me 1 second!

It’s good to have an understanding of the aberrations at play in order to judge whether a lens is a good or a poor performer. But, testing for aberrations is judging them from a negative perspective. You are essentially trying to find its faults.

Imagine meeting a potential life partner interested only in finding YOUR faults. Would that be a sound base for starting a long-term relationship ? Obviously not.

This can only lead to seeing the worst in your gear and missing out on the great parts. Take that B&W “Exhausted” photograph (2nd from top). It is made with the Zeiss C-Sonnar 1.5/50 ZM at full aperture. There is so much flare and chromatic aberration that the out-of-camera photograph looks like fireworks, but the end-result just sings. That same lens was used (on the same day) to make the photograph below. Aberrations? What aberrations? That photo could be printed 40″ wide it is so sharp and delicate. Colours are superb. 3D is perfectly natural.



Zeiss C-Sonnar 1.5/50 ZM

Zeiss C-Sonnar 1.5/50 ZM




Once you understand what a lens does and how and why, the most important step for you is to determine whether you like that or not. And this is probably the most important step you can take on your way to chosing gear to become a creative photographer! Because testing gear is finding fault. Finding fault and, with the method outlined in the previous pages, deciding whether the flaws are a serious issue for you or not. But ultimately, it is all about finding faults. Negative thinking never gets you very far in the world. Particularly not in the world of creativity.

So, now that you know how to test lenses, you must start to worry less about faults and begin to focus on creating an alphabet of positive aspects of lens rendering, just as I learned to describe wines I like.

And finally, as rational as our decision forming is, all purchases are irrational. We must all acknowledge the little child that is still inside us and that is shouting “I want that one” or “Oh, no, it’s very good but I don’t like it”. Letting the child’s intuition guide you intelligently is the final step towards successful gear acquisition. Gear that will stay with you for many years, that will serve you well, will not necessarily depreciate over time …






So we will be back! This introductory course is just a part of a larger one that we are currently building to help you do just that: perform a very rational analysis of a lens or camera, then look into the more personal and subjective aspects of purchase decision-making, and assemble the perfect camera bag for your style, level of proficiency and budget.


This course will look into the following topics:

  • Understanding technical brochures
  • Reading MTF curves
  • All about sharpness
  • Answering the nagging “is my lens a gem or a lemon” ?
  • Defining an alphabet of positive and creative characteristics lenses (bokeh, contrast, artistic veil, sharpness, …)
  • Testing gear in the field (containing a larger version of the course you have just received plus a similar one devoted to camera bodies)
  • What to look for in a camera
  • What impact sensor size has on images
  • Letting aesthetics play the vast role they should in your decisions
  • Allowing the irrational to have its say, intelligently


It will condense all that we have learned over a collective century of shooting and is intended to fast-forward you to simple, yet informed, decision-making and to provide a lot of fun in the process. We will help you avoid the numerous expensive and demoralising mistakes we made over the years. And, more importantly, we will answer your questions personally.


Zeiss Loxia 21/2.8

Zeiss Loxia 21/2.8


We want you to succeed as photographers and will help you to our best ability. But that’s not all. Before we release this course, we want to hear from you ! We want you to tell us what you are struggling with the most and what topics you would like us to include in the course. We want you to tell us the type of learning you’d prefer. Are you a video person, or is text like this page the best. Do you need and prefer interaction with us and stimulation or are you the type that prefers to digest things at your chosen pace and alone?

So let us know now, in the comments below or privately by clicking the link below.


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  • Marc Baillargeon says:

    Great article and solid wrap-up! Thanks again!!

    A possible topic to add to your “perfect camera bag” would be about lighting aids. Be it flashes, strobes, modifiers, reflectors, remotes, etc. All in the context of carrying weight and size sensible equipment (so that you simply carry it all the time whether you know or not whether you’ll need it) often useful to compensate/aid natural lighting.



  • Yeahhh says:

    Very nice wrap-up of the lessons. I’d added the same. Now it’s time to take the flaws and turn them into gains. What defines the character of a lens? What is my preferred style? How can I find it and describe it? What about color rendering and 3D/depth (and not just bokeh and fast aperture)? Particular the last one interests me most: I fail to nail it.

    Your review of the Zeiss C-Sonnar or the Otus’ impressed me a lot. I’d like to be able to examine a lens like that too. Where are its weaknesses and where are its strengths? And where’s the link between booth?

    Concerning the course I think it was a little bit too basic for me. It felt more like a glossary. I missed pros and cons, but maybe that’s part of the next course. In the beginning you claimed, all those brick and test chart reviewers miss the point of photography, but in the end this course taught us to do the same solitary testing but in the fields. But maybe there’s some red line to the next installment. If I’d paid for it, I’d be a little bit disappointed so far. For free, well I can’t complain. From your wrap-up and introduction I expect the follow-up course to have this red line, and I’d probably pay for it.

    For the medium, I somehow liked the step-by-step way, and I somehow didn’t. I liked it because it made sure you had enough time to read, understand and practice each section. On the other hand I had to adapt my speed to it. The release cycle was a little bit fast for me. I’d appreciate a once per week installment. Best day would be Thursday or Friday, so you can practice on the weekend or the other week. If you send it out faster (like the two days now), you get new lessons without having the time to get into the depth, and than don’t do it at all. Or you end up going on your own pace which defies the purpose of sequential releasing.

    Furthermore some graphics would be helpful (to support non-native speakers with technical terms) and a PDF download at the end.

    For video vs. text: Video is very convenient but text remains longer. Accentually both accompanying can make sense, depending on the content. With interaction and stimulation with you, I have no idea how that could look like. Because of that I’d say I prefer to digest alone at my own pace.

    • pascaljappy says:

      Wonderful feedback, thank you.

      We are indeed planning much more in-depth training and this first course serves as an into and to get everyone to the same level. So it’s bound to be a little slow for some and a little fast for others. I like your suggestion of a weekly pacing and we will definitely include more graphics in the future course.

      All the best,

  • Steve says:

    Pleased you will be continuing to educate and entertain us.
    I like the present format, I get bored by all the video kit tests and comparisons. This is ‘fresher’, even if it is ‘old’ style presentation.
    As regards other topics, I’d like something on flash techniques (as opposed to lighting technique), remote triggering and some independant thinking on post processing.

    Keep up the good work and thanks.

  • cedy says:

    I prefer text over video. It is so much easier to refer back to and going to the specific point you want to review.

    Depth-of-Field, I think, is a topic worth discussing. I find most DoF calculators to be useless in the world where images are displayed on 27″ monitors or 55″ 4K television screens. While I understand the concepts, some guidelines for usage would be wonderful.

  • Micheal says:

    I am interested in most things photographic. Flash, perhaps fill as I tend to shoot with natural or existing lighting. Ideas on how to make the most of my gear by understanding it better. This vague and difficult with out being specific about gear. But you did an excellent job with the lenses and their inherent defects and suggestions on how to live with them… or not. At least I know why I don’t want to use that lens.
    Cameras with their design trade offs and what they are best suited for portraits, street, landscape, nature, or sports.
    Tripods… why carry one around and never use it?
    Filters, why use one? Polarizer (Linear or circular), ND filters, or unique special featured filters like a starburst.

    I like the format, slower time frame is better but if faster please make them available for me to work on them when I can.


  • LW says:

    So true!
    I find if you keep emphasizing the negatives, in the long term, it will kill your creativeness as well. Furthermore, you will never be satisfied with your own pictures because of that… Creativeness thrives within limitation!
    Lets focus on the positive, weather it is on gear or on life!
    Great article, cant wait for the next series!

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