Comments on: Photography 101 – Lenses and Focus

By: Brandy

Brandy — Fri, 30 Dec 2011 01:38:06 +0000

I LOVE YOUR LESSONS!! THANK YOU so very much! I needed to know the why behind the how and your lessons are by far the best, most organized gatherings of necessary information that I have found online. I feel blessed to have stumbled upon them. Just what I needed.

By: Bradles

Bradles — Fri, 23 Dec 2011 22:05:41 +0000

Anas I believe the shift in focus is acheived through a slight change to the focal length. I tested this with a 50mm prime mounted on a tripod with focus set to infinity and the closest point. The 2 images produced markedly different fields of view as shown in this blog post on how focus works Neil, thanks for these lessons. I'm really enjoying getting into the theory behind photography.

By: Monica

Monica — Mon, 08 Nov 2010 01:16:59 +0000

I have always loved photography, but am just now making a decision to dive deeper into it. I recently got a Nikon Nikkormat EL – camera w/ numerous lenses, from my grandfather. I am very knowledgable in the digital technology so, utilizing w/ 35 mm film is going to be an adjustment. Can you recommend a good source to understand this camera & all of it’s functions & what everything means???

Thank you,

By: Anas

Anas — Thu, 22 Apr 2010 13:04:56 +0000

Hi…. Thanks for the tutorial.

I appreciate theoretical approach such as this, in fact i long for more in depth technical explainations especially the mathematical side of it.

I have a question.

When we want to capture an image with a camera, we pick a lens, say a 50mm prime lens. It has a fixed focal length of 50mm.

Focal Length is the distance between the “middle” of the lens and the focal point.

according to your animation, as subject to lens distance change, we have to move the lens forward/backward. It also shows that the distance between the focal point to the middle of the lens have changed, wouldnt this means that the focal length also has changed?

as with photographic lens, the focal length is fixed, but we can still adjust the focus to selectively focus near or distant subject.

can you please relate this more with the photographic lens.

thanks!

By: Luke

Luke — Mon, 05 Oct 2009 17:11:49 +0000

Thank you very much!
I´ve been photographing “by ear” and I think now it´s time for me to learn it properly, So I really dig your classes so far. Thank you!!!

By: Julie

Julie — Sun, 16 Aug 2009 21:08:17 +0000

I’d just like to say thank you very much for explaining the elements of camera obscura, it is something I’ve never quite got my head around until now – its simple once you know!

By: Vanessa

Vanessa — Mon, 06 Jul 2009 15:10:02 +0000

I also found this extremely helpful! I have been wondering about the “WHY’s” for the past few months that I’ve studied photography on my own ( I am a newbie), and no one has explained it as well as you have. Maybe it is not the best for someone who just got a camera and is looking for a quick formula (which doesn’t exist!) ; but it is PERFECT for those of us who learn this way and want to have a clear picture of what a camera is and does before attempting to take pictures in a skillful manner.

By: Vivian

Vivian — Mon, 29 Jun 2009 19:43:36 +0000

Hi,

I am at my wit’s end so it would be a great help if you answered my query…I have a 16 mm lens for a CCTV camera. The image plane is 6.3mm (H) and 5.4mm(V). Due to constraints, I can place the lens at maximum the focal distance of 16mm. The object I want fitted into that image plane is approximately 35mm x 15mm or a bit larger. Is it possible to get a sharp image of this object?

Its not a pinhole camera..the lens has an extra angle of 19 deg.

Thanks for any help offered

By: Elizabeth

Elizabeth — Sat, 25 Apr 2009 04:59:38 +0000

These lessons are great! I agree with the benefits of discussing theory and physics. I’ve been reading lots of information about how to understand all of this stuff and your lessons are the first that I can actually grasp, understand how photographs are created and therefore am retaining the knowledge so I can use it in the field.

I’m reading through all of the lessons now and plan on trying some of the homework assignments.

Thanks!

By: Beverley

Beverley — Fri, 06 Mar 2009 19:33:12 +0000

Hi, I’m new to your tutorials and am loving them. I teach 11 year olds and have already used the pinhole camera to explain light paths, I now want to set up your magnifying glass experiment. I have been into photography for a year now and understand a lot more than I did at the beginning – your tutorials are strenthening my foundations and giving me the will to improve. Thank you.