Guestbook

Kelinci (Thursday, 16 June 2016 02:41)

Your article is really getting better, and we will continue to focus on your latest work

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My friends say the article is written very well, really well written, refueling, we will support you!

jordan shoe (Saturday, 07 March 2015 00:37)

Your article is really getting better, and we will continue to focus on your latest work!

Michael (Tuesday, 09 September 2014 05:12)

Thanks Natalie for your lens family tree I have been interested in the history of lens development for a long time this really filled in a few of the gaps for me. This is a remarkable piece of work and a wonderful illustration of lens history that all serious photographers should be aware of I congratulate you for a job well done!.
Now please publish a list of the lenses in your draw it's quite a collection and I am dying to know what they are :)

John Barton Wood (Tuesday, 26 August 2014 09:17)

Hi Yuri,

I am a retired engineer living in the UK. I served an apprenticeship as an optical instrument maker back in the early sixties with Rank Precision Industries: A. Kershaw & Sons and Taylor Hobson divisions, in Leeds and Leicester respectively.

The reason I am getting in touch is that I am looking for an 85mm F1:2 lens for my NX300. I have many, many, older lenses from 1" macro objectives to 600mm F1:4.5 Kinetheodolite and 36" F1:4 air reconnaissance lenses along with a number of legacy M42 and Olympus Zuiko 35mm format lenses which I am using to good effect with the NX.

As part of my search for an 85mm F1:2 for the NX I saw your comparison tests of the Minolta MD 85mm F1:2 and the Jupiter-9 equivalent on the allphotolenses.com website. Overall, I found it to be a very interesting and informative article and you are to be congratulated for publishing your results. However, I was troubled by what appears to be a (common) misunderstanding of light paths through lenses relating to cropped images at the focal plane.

You state the following: "Please note that at a crop factor x2 real edge of lenses are not used." If, by these words, you are saying that light from near the physical edge (outer zone) of the lens does not impinge on the inner, un-cropped, part of the image then you are mistaken. If not then please ignore the rest of this message. However, if you are then please read the following explanation:

Rays of light from all points of the object field pass through all points of the lens onto their corresponding point in the image field (this is the main aim of the designer). That is why, in ray tracing, rays are taken from an absolute minimum of two points of the object and pass via the centre of the lens and its periphery to the corresponding image points - in practise, during the design of a lens, rays are taken through a number of zones to assess and reduce the various aberrations of the lens as a whole. In other words, light that passes through the outer zones of the lens is not solely used to illuminate the outer parts of the image but ALL parts of the image.

It may be that this misconception has arisen because very wide angle lenses seem to have very large front apertures but that is just the result of requiring enough glass to allow light from all parts of the object field to arrive at the image field, i.e. to capture the full cone of light at the stop at the centre of the lens. The fact that the required image circle is smaller than the designed for image circle does not mean that the peripheral zones of the lens are not used for the smaller image. Having said all that it should be noted that the extra light allowed into the lens, from wider angles than required, should be managed so that it does not, by way of internal reflections, impinge on the image with detriment to contrast.

Please do not be offended by the above comments as they are only meant to be constructive. Please also note that I had no intention for this to be displayed in the guest book as it was the only way I could message you as to my concerns. Accordingly, you may do with it what you may.

Kind regards,

John

Keep up the good work.

alissa.everett.mn@gmail.com (Friday, 15 August 2014 11:01)

Hi,

I just checked out your portfolio and I wanted to say that you have some great photos there! I can really tell you put a lot of feeling and effort into your photography.

Also, I want to thank you for following me on Twitter (medianovak). It's really an honour to know that people are interested in what my company and I have to offer.

Keep up the good work and thank you again!

Alissa Everett,
MediaNovak | Photography Websites & Logo Design

http://medianovak.com

Bob Coe (Tuesday, 15 July 2014 09:53)

I came here for info on old lens, but I enjoyed your photography much more so thank you.

Bob

Stan Feldman (Saturday, 28 December 2013 21:53)

Wonderful use of colors. Enjoy your work !

Thomas Wuthrich (Monday, 09 December 2013 05:56)

Beautiful work, Natalia!

David Renson (Saturday, 11 February 2012 15:35)

I am very glad, to have seen more of your soul, what is loved in your eyes, and wonderful painted by jou!

best regards

David Renson

Марина Шарунова (Sunday, 06 November 2011 10:37)

Здорово!!! Наташ ты ТАЛАНТ!!!