I was reading this post at https://communities.bentley.com/products/microstation/f/z_-archived-microstation-v8i-forum/69397/microstation-v8i-design-file-advanced-setting-resolution and was wondering how someone would have determined that changing the Design Resolution setting “changes the size of existing geometry in the model”, as stated in this post? The only thing that I have noticed from tests I’ve done on this is that these settings affect the ability to zoom in as close as one might want to in their model. I have done some minor testing on this and below is what I have found . . .
Our company has their seed files (2 – one for State Planes East and one for State Planes West) for surveys in the state of Alabama with the following Design Resolution settings . . .
However, with the settings shown above, my ability to zoom in as much as I would like on certain elements are hindered. From what I have tested, simply changing the Advanced Settings > Resolution: to the settings in the next screenshot does nothing to the size of the geometry, but does allow me to zoom in closer to objects than the previous settings do . . .
Since I am relatively new to MicroStation (maybe 3 years total in the last 10 years, but a 25+yr. AutoCAD user) I am not sure exactly why this is so, but I have two test drawings created from the same seed file with the only changes being made to the settings being those shown in this last screenshot. Distances I’ve measured in both of these test drawings seem to be exact, and Google KML files created from both seem to appear in the exact same location on Google Earth. How could this be so if changing these settings would result in changes in the size of the geometry as the post about has stated?
When I run that same scenario (change resolution from 10 000 to 10 in the design model) my graphics change.
On your screen shot I see the 12 per survey foot changes to 10 000 per meter. If I do similarly I get that 3.2808333 factor.
So I'm miss interpreting your question.
Connect r17 10.17.2.61 self-employed-Unpaid Beta tester for Bentley
I may not have explained myself like I should have. If i understood the original post, it said the size of the graphics change, which lead me to believe (along with his warnings to leave those settings alone) that the actual lengths of graphic elements changed with altering these settings. In other words - change the settings and a 3' door no longer measures 3' wide in your Microstation model. I understand that the "viewing" of the graphics change because of the resolution difference, but I cannot see how the actual graphic elements could change in size or in georeferencing due to the same. Am I just misunderstanding the post? The reason I ask is because I believe our seed files need to be changed to the settings that would allow us to zoom closer, but it was brought to my attention that this "might" be set because of its necessity to proper scaling/location of survey elements.
If you change the resolution, you *do* change the "measured size" of the elements. The "relative size" (of one element to another) does not change. The "resolution" is how you map real-world dimensions to the way the program stores that information internally. It also determines your amount of "accuracy" of your measured data. The higher the precision, the more the accuracy. In your example, you have "12 per Distance US Survey Foot", so you "measurements" are essentially limited to whole inches (1/12 ft). In other words, you cannot place a line that is 1.5 inches long - it will be either 1" or 2" because your "resolution" is so low. If you changed, for example, to "12 per Distance US Survey Inch", now your accuracy would be 1/12 in, so now you could at least have lengths in the 1/10" range.
lets take your fist screenshot.
If you drew a line 10 feet long with the settings from that first screen shot, it would be represented in the file as 120 points (resolution 12 per foot).
Now if you change the resolution in the file, the line is still 120 points long, you have just changed what the points represent.
Lets say (to keep it simple) you changed the resolution from 12 to 120. The line is still 120 points long, it will just measure different. In the first case it would measure 10 feet and in the second case it world measure 1 foot.
Hope this makes sense.
Here is another article that discusses some of this in detail:
https://communities.bentley.com/other/old_site_member_blogs/bentley_employees/b/tim_hickmans_blog/posts/survey-feet-vs-international-feet
Timothy Hickman
CADD Manager | CADD Department
timothy.hickman@colliersengineering.com
Main: 877 627 3772|
1000 Waterview Drive Suite 201 | Hamilton, New Jersey 08691
Rayford,
Think of MicroStation's design plane as a huge piece of graph paper. What you are doing in the "Advanced Settings" part of the dialog is telling MicroStation the spacing between tic marks in the graph paper. With the settings in your first screen shot, when you draw a 1 Survey Foot line, it takes up 12 tic marks. Now suppose you set the Resolution instead to 12000 per foot - then when you draw a 1 foot line, it takes up 12000 tic marks. MicroStation's windowing tools set a minimum number of tic marks that you can see at a time, that is why you can zoom in closer in the second case than the first.
Accuracy, however, is not changed, because the actual coordinates are stored in double precision floating point. So if you wanted to draw a line that is 13 inches, in the first case it takes up 13.5000 tic marks, where in the second case it takes up 13500.0 tic marks. The accuracy is the same.
Because of the limitation on zooming in, however, I suggest you use 1200 or 12000 rather than 12.
To do the test you are describing correctly, set up the Resolution as 12 and raw a one foot line. It will measure as 12 inches or one foot. Now change the Resolution to 12000, and that same line will now measure as .001 foot.
Barry