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Shelender kumar  20111026 11:03:59 
Fantabulous,marvoulus,burrrrrrrah..................... 
richard harding  20111024 04:28:20 
Thank you. I stumbled on this site as I was reading the book "Godel, Escher, Bach", by Douglas Hofstadter. Your site elaborates in greater detail some of the concepts in his book. Your website is wonderful! Thanks again! 
Angela Maria Camara Nogueira da Gama  20111002 17:38:12 
É incrível o talento de Escher e arrebatador.
Foi para mim o precursor da ideia de sustentabilidade, no moto contínuo que materializou, onde a energia potencial da água em queda se transforma em mecênica da roda d'água, criando um movimento infinito sem consumo energético.
Um matemático que desenha, um desenhista que calcula.
Gostaria de ter conhecido de perto seu processo criativo! 
Roger J. Tremblay, PhD  20110924 18:13:22 
Inspirational example of how a complex but beautiful application of mathematics can be presented with such clarity. I have never seen anything quite like it, web, television, text or live presentation (should be presented at TED?). Thank you for your efforts. 
Thank you for the interesting site! Spooky mathematics, luckily you have the stop button. 
Drs. Albert Spijkers  20110814 16:27:00 
I always liked Droste Chocolate, but makes you fat. But al fun aside, I had a book once about Escher explained, but WebGL can do a much better job explaining Escher's Lithographs. Infinitely moving down in the drawing details, like with fractals. 
wayne ferguson  20110809 02:55:05 
i am looking for the mantis 
Baumann Eduard  20110720 18:05:52 
Nice, this infinity with the limited AVI file. 
Marcia Weinhold  20110708 00:18:45 
Thank you! This is fascinating! 
RyanGeorgia  20110706 10:35:29 
Great site! Escher is one of my favorite artists ever, and you did a great job explaining the mathematics behind the art. 
Brilliant...on both Escher's and Lenstra's part... It is so interesting to see mathematical and artistic intuition crossfertilizing. Grand unification of art and math  rather than GUT in physics. Escher/Lenstra personificaton of intuitive mathematician/artist. Always been fascinated by Hofstaeders book  Goedel, Escher, Bach and somehow this analysis kills the notion of incompleteness of Escher. 
Cathy  Pittsburgh  20110502 17:54:44 
As perfect a blend of art, imagination and mathematics as I've ever seen: a genius' work! ☺ 
Bill Hackborn  20110416 02:38:50 
Great site! Very interesting. 
Thank you very much for sharing your work at Grinnell College. Your presentation was extremely interesting and entertaining. 
Hello,
Glad to see fellow Escher enthusiasts, I have been curious about him for many years now, and as the days go by, my curiosity increases, I cant wait to see what you come up with next! 
Chris Miller  20110404 22:29:02 
This is a very interesting topic. I had always wondered about the "scotoma" in " the Picture Gallery". 
Aditya TVM  20110305 07:25:21 
Thanks a lot, if not for this site, i wouldn't have know the existence of EscherDroste effect(i accidentally came across this site) and the whole process of how this genius artist made his awesome artwork... :)
i will try sketching with the reference to Escher's graph... thanks to your step by step detail description and examples:)
Thanks again... :) 
Hans Wassink  20110220 10:06:05 
Of all the ways man can spend his time, this is by far the best. Keep it up! :D 
Anton Älgmyr  20110123 01:43:16 
Thanks for the great lecture at the Sonja Kowalevsky days! It was by far the most interesting one we heard in the whole weekend (the participant's survey confirms that as well)!
I doubt you remember this, but I was the one who couldn't resist giving you a thumbsup when I saw you just after the lecture. ;)
Take care! 
Carla Blankevoort  20110105 19:41:39 
What a genius and wonderful that his genius lives on through this site and has other young geniuses working out his methodology! I wish I was clever enough to work it out myself, well done! 
escher is een flut schilder. 
Dr. Tom C.J. Gribnau  20101114 12:21:14 
Excellent work rding an excellent "artist" 
Gustav JonssonGlans  20101114 00:39:16 
Great lecture at the Sonja Kowalesky days! Was really fascinating and inspiring, I'll look further into the technical aspects of this method. 
Gustav JonssonGlans  20101114 00:39:00 
Great lecture at the Sonja Kowalesky days! Was really fascinating and inspiring, I'll look further into the technical aspects of this method. 
Jan Hus  20101110 23:44:25 
I never heard of the Droste effect, but I vividly remember the Drosty container as a five year old. It must have been in 1933. My mother was in the hospital in Singapore and a Droste can was sitting on the table beside her bed. I think I was trying to see how far back I could still see a can. I did not remember the Droste name, but I was amazed to see the picture again. Wow the Droste effect. Thank you.
Jan Hus 
Judai Burton  20101003 16:10:34 
a fascinating look into liberal arts math! 
Andrew Wyszkowski  20100930 05:43:30 
Thank you for this study. I now have to digest it.
Best regards. 
Beautiful stuff!
..thank you. 
jock mctavish  20100825 05:57:54 
you do him honour
and extend our curiosity
in the same way he first attracted us
very well done
thankyou 
Guilan Raphaelle Gistand Runty  20100808 00:33:10 
Uitstekend! Dank je wel! Nous pouvons exploiter les excellentes informations sur ce site, Merci pour les instructions du grand professeur de Recife (Brésil), le Prof. Dr. JOSÉ CLAUDINIER DE FREITAS FILHO. Fabulous économiste, maître, écrivain, commissaire de la Trésorerie, analyste de systèmes et spécialiste de la culture, en particulier dans le nordest du Brésil.
Guilan Raphaelle Gistand Runty – Avignon  France – graphaelle@hotmail.com 
Tonya M.  20100803 00:57:33 
On August 1, 2010, I saw this at the New Britain Museum of American Art in CT, USA. Amazing to see this animation and plenty of Escher's originals in person! 
Xezlec  20100619 17:21:02 
It would be interesting to use some version of hypercomplex numbers to do the same trick with a threedimensional grid. Make a 3D gallery that contains itself, for instance. Anyone trying that? 
Xezlec  20100619 17:13:56 
Wonderful explanation! Thanks for this. 
Cheryl  20100617 15:20:48 
This is amazing!!!!!!
Thank you for giving such a clear explanation. 
very confusing Oo, the artist drew very well, we're talking about this picture in mathematics ^^
from switzerland 
this is amazing !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ive never seen anything like this before i tell my friends about this . i like this guessed book lots .
thank you for your time .
from k and k :) 
this is us people and we like this a lot !!!! from k and k :) 
Shannon  20100513 20:14:48 
So trippy, I feel like I should be on acid. Sitting in math class, teacher made me check this out. 
Reinko  20100330 22:17:18 
This evening (30 March 2010) I visited a public lecture (the so called Bernoulli lezing in Groningen) given by Mr. Lenstra.
In the lecture Lenstra explained a bit of the math used, most boiled down to taking the log of a picture and 'store' that in the computer.
(This is not that difficult, you go from rectangular to polar coordinates and apply the complex log. A piece of cake.)
But you can also create easily a picture with eight of those disappearing points, think for example an ... read more 
rinke Visser  20100329 12:11:02 
rinke Visser  20100329 12:08:01 
Michael Hann  20100324 15:13:20 
Arlene O. Consiglio  20100323 17:14:11 
I have Art. No. 80 2351 1943 Cordon Art Baarn Holland Made by Pussycat 32075 Bad Salzuflen, Germany.
I am looking to get an appraisal. It has never been used and is a picture of Reptillien/Reptiles, 1943 
Serena  20100309 17:06:45 
I saw u on Plenty of Fish and you said to check out the website members.cox.net/jcl3622
That is what I am trying to do
I don't know the last name of the artist to whom this site is devoted...help 
hennie  20100307 01:40:26 
Ik vind het werk van Escher zo fascinerend!
Erwin bedankt voor het leuke programma gebaseerd op het Droste effect
www.sansevaria.nl 
Andrea Wall  20100128 07:50:12 
Very interesting! I never knew about the Droste effect in Escher's art. It was fantastic! 
Erwin de Groot  20100126 09:47:02 
Awesome work. I should've found out about this site a while back before I started writing my own software (that would've helped a lot). Anyway, in case you're interested I made an application which can create these Droste images with a spiral: www.photospiralysis.com. 
Richard Millette  20100108 21:57:52 
I'm so glad to have found this site. I saw a documentary about the whole project a few weeks ago and have been fascinated by it since. I'm sure Escher would have used the computer for this project, if it has been possible at the time. Amazing work, thank you. How about something with Magritte, now?... 
Frauke  20100101 21:18:56 
This site is very interesting for me because I and a friend of mine take part in a German competition called "Jugend forscht"(I'm a German, you know). We write texts about platonic polyhedra used in art. Escher used them in some of his pictures, so we want to know many things about him, too. You made very clear how this Droste effect works. Still we don't know if we might use this in our texts just because it is not about platonic polyhedra although you made a very magnificent work. 
