tag:blogger.com,1999:blog-2999230124118604245.post1519456705674680049..comments2024-03-28T16:36:12.581-04:00Comments on Gurney Journey: Using Depth of Field in PaintingJames Gurneyhttp://www.blogger.com/profile/01870848001990898499noreply@blogger.comBlogger7125tag:blogger.com,1999:blog-2999230124118604245.post-26767800709175942182021-11-07T18:57:35.407-05:002021-11-07T18:57:35.407-05:00In photography, pinhole camera models and projecti...In photography, pinhole camera models and projections, Z-axis is used to signify the depth of field. <br /><br />Mr Gurney's notation is consistent with how perspective is represented in academic notes today. Anonymoushttps://www.blogger.com/profile/13921546569822338168noreply@blogger.comtag:blogger.com,1999:blog-2999230124118604245.post-62503128642528170372021-09-14T11:48:52.353-04:002021-09-14T11:48:52.353-04:00When discussing a flat painting, the two dimension...When discussing a flat painting, the two dimensional cartesian coordinate system is used where X and Y describe the physical plane of the painting. Z isn't really used but could be invoked to describe the implied depth of the image as Mr Gurney does here.<br /><br />When discussing a 3 dimensional item (as used by CAD and 3D programs), the same cartesian system uses X to describe the left/right horizontal coordinates, Y to describe the depth (closest to farthest) and Z to describe the vertical/height/depth coordinates. However, I have seen older 3D software that continues to use Y for the height/depth description and Z for the depth description.Pierre Fontainehttps://www.blogger.com/profile/09928175455443075350noreply@blogger.comtag:blogger.com,1999:blog-2999230124118604245.post-43378760298956404682021-09-14T09:02:44.816-04:002021-09-14T09:02:44.816-04:00Kalp, thanks for pointing out that I'm using t...Kalp, thanks for pointing out that I'm using the "Z" term in an unorthodox way. I'm defining the term Z-axis as a normal of the plane defined by X and Y, independent of gravity. In other words, Z is the vector perpendicular to the picture plane, whether the picture is sitting flat on a table or vertical on an easel. James Gurneyhttps://www.blogger.com/profile/01870848001990898499noreply@blogger.comtag:blogger.com,1999:blog-2999230124118604245.post-28132611172908793952021-09-14T08:46:07.977-04:002021-09-14T08:46:07.977-04:00Interesting. I thought Z-axis was referring to the...Interesting. I thought Z-axis was referring to the vertical plane, like physically from the ground skyward. That's mostly because I usually think of geometry in relation to Computer Graphics (CG). Is there any particular merit of imagining space in the way you described, especially when it comes to painting?Kalphttps://www.blogger.com/profile/16568909972159342535noreply@blogger.comtag:blogger.com,1999:blog-2999230124118604245.post-19831957684956915262021-09-14T08:44:29.178-04:002021-09-14T08:44:29.178-04:00Interesting. I thought Z-axis was referring to the...Interesting. I thought Z-axis was referring to the vertical plane, like physically from the ground skyward. That's mostly because I usually think of geometry in relation to Computer Graphics (CG). Is there any particular merit of imagining space in the way you described, especially when it comes to painting?Kalphttps://www.blogger.com/profile/16568909972159342535noreply@blogger.comtag:blogger.com,1999:blog-2999230124118604245.post-1040861770589465762021-09-13T16:50:28.666-04:002021-09-13T16:50:28.666-04:00Forrest, good question. Usually I think of the pic...Forrest, good question. Usually I think of the picture plane as defined by the X and Y axes, and the dimension perpendicular to those two lines (close to far from your eye) would be the Z axis.James Gurneyhttps://www.blogger.com/profile/01870848001990898499noreply@blogger.comtag:blogger.com,1999:blog-2999230124118604245.post-61477770939681350792021-09-13T15:02:22.259-04:002021-09-13T15:02:22.259-04:00Can you elaborate on the Z-axis, etc. Sorry, I fe...Can you elaborate on the Z-axis, etc. Sorry, I feel silly, but I want to make sure I understand which direction that is. :) For that matter, which axis should we be concerned about in a composition with this depth of field technique in mind? forriehttps://www.blogger.com/profile/07746515846739364861noreply@blogger.com