[Qgis-user] Re Did scale change outputting to PDF?
This issue has been solved. Trying to estimate the scale by taking measurements on the paper maps failed despite every advantage that should have maximized the precision of the measurements. A distance measured north-south yielded a different scale than a distance measured east-west. Averages of ten of each yielded different scales in these two orientations. The only thing I can think of that would produce that result is that the image was distorted differently in height than it was in width. But the whole issue was resolved when Kinkos agreed to examine the process and reprint the job. After one test panel, they told me they figured out what had happened (although they didn't tell me what that was). They reprinted the big panel and one small parcel map, and they line up perfectly just as I had planned. They are in the process of reprinting the rest of the panels at no cost to me. For long-story reasons I'm not inclined to share, I didn't think they would do that. The rest of the work going forward is going to be SO much simpler because of that. Thank you all for your help! - John A. John, Is it possible to ask Kinkos what scale they printed the base maps? They don't have to actually reprint the maps, just go through the motions. Open the PDF and look at the print options. As Andreas points out, the default is often "Fit" and there will be a "zoom" or "scale" percent displayed in the application (I use Foxit, and Adobe and both show this). The page size parcel maps will have to be printed at this scale. If they can guarantee that the print scale was 100%, then I would assume some other export discrepancy. David On 5/27/2021 4:15 AM, Andreas Neumann wrote: Hi John, No - the PDF export does not distort the scale. But the printing of the PDF file might. It is absolutely important that - when printing the PDF - the setting "Actual size" or "Custom Scale at 100%" is used. All other options will change the scale. As far as I know, the default option when printing is "Fit", which will often shrink the content by some percentage - because some often "invisible" or white background might be present in the file that extends right to the edge of the page format. Acrobat then thinks that the content goes beyond the "printable area" of the printer and will scale down the whole file. Hope that clarifies this potential pit-fall when printing PDF files. It might well be a different issue than the one I describe, but this is a very common source of error that I know. Andreas On 2021-05-27 10:02, John Antkowiak wrote: Hi, Jochen. Your suggestion sounds do-able; I'll play around with it and see if I can sort it out. I've got some digital calipers around here somewhere :) What I'm hearing is that the process of converting both the base map (and yes, I did create it in QGIS) and the parcel maps into PDF will distort the scale. (And that a print shop might compound the problem by manually fitting the source file to the printable area. Yes?) A question then is why didn't the PDF conversion distort them all the same way, to the same degree? The base maps are done now and I couldn't afford to do them again no matter what, so they are what they are. Going forward, is there an export option in Print Layout that will not distort the scale of the parcel maps? I am so relieved that someone has an explanation for this! - John A. - Forwarded Message - From: j.hu...@post-ist-da.de To: "qgis-user@lists.osgeo.org" Sent: Thursday, May 27, 2021, 03:33:12 AM EDT Subject: Re: [Qgis-user] Did scale change outputting to PDF? Hi John, as I understand it, you created the base map in QGIS. If you use the measure tool in QGIS to get the distance between two distinct features in the map (e.g. road intersections) and then measure the same distance on the printed base map with a ruler, it should be possible to calculate the scale. Maybe use two distances, one aligned more or less horizontally and one vertically, to check if the scaling is proportional. As Andreas pointed out, it is probably a problem with the settings when the PDF was printed. In my experience it is a good idea to go to print shops usually working for architects and engineers since they are familiar with the importance of scaling (for advertising etc. it is more important that the whole content is printed, so that scaling might be used to fit the output to the printable area without potential cropping). You can print directly to a plotter in QGIS if you have access to the device, avoiding the PDF detour. EPSG 2264 should be fine. Units should be US feet. Regards Jochen Am 27.05.21 um 07:15 schrieb John Antkowiak: Hi. This plan was too simple to fail - but it failed. The charity whose project this is needed a large (that is... massive) paper wall ma
[Qgis-user] Fw: Did scale change outputting to PDF?
So...h. When I measure the distance in QGIS, I'm given the choice to use the Ellipsoidal method or the Cartesian method, which yield different distances. Which one of those two choices is my wooden ruler using? Because if they're not the same, the resulting scale isn't going to match... Seems like this shouldn't be this difficult lol... - John A. - Forwarded Message - From: "j.hu...@post-ist-da.de" To: "qgis-user@lists.osgeo.org" Sent: Thursday, May 27, 2021, 03:33:12 AM EDTSubject: Re: [Qgis-user] Did scale change outputting to PDF? Hi John, as I understand it, you created the base map in QGIS. If you use the measure tool in QGIS to get the distance between two distinct features in the map (e.g. road intersections) and then measure the same distance on the printed base map with a ruler, it should be possible to calculate the scale. Maybe use two distances, one aligned more or less horizontally and one vertically, to check if the scaling is proportional. As Andreas pointed out, it is probably a problem with the settings when the PDF was printed. In my experience it is a good idea to go to print shops usually working for architects and engineers since they are familiar with the importance of scaling (for advertising etc. it is more important that the whole content is printed, so that scaling might be used to fit the output to the printable area without potential cropping). You can print directly to a plotter in QGIS if you have access to the device, avoiding the PDF detour. EPSG 2264 should be fine. Units should be US feet. Regards Jochen Am 27.05.21 um 07:15 schrieb John Antkowiak: Hi. This plan was too simple to fail - but it failed. The charity whose project this is needed a large (that is... massive) paper wall map on which to plot and rethink its delivery driver assignments. Both drivers and delivery addresses are subject to change from week to week but it's not a pizza delivery; this is a regular run to supply people in a bad way. So the plan was to print the base map (roads and road names and county boundaries only) and then print 8.5 x 11 address maps with parcel data and orthos. That way, the base maps don't change but the physical parcel layer is flexible. (On top of that is a third paper layer indicating which drivers go where so someone can stand back and take in the whole picture graphically. Not a cutting-edge state of the digital art solution, but not everyone is cut out for that. It is what it is.) In order for this to work, the parcel maps have to be the same scale as the base map. Which they were... in QGIS. We have to convert all the maps to PDF to print them, and we had to send the base map PDFs to FedEx/Kinkos to print the 9 map grid panels at 42" by 62" each. When we got the big base maps up on the wall, we discovered the scale did not match the 8.5" x 11" parcel maps output to PDF and printed from home. It's not off by a lot, but it's enough to be painfully obvious from a single standard size sheet of paper. I don't know how to reverse engineer the big map scale precisely enough to enter a new scale number in the QGIS Print Layout. I didn't foresee it because this never would've been a conceivable scenario at the engineering firm where I picked up my meager GIS skills. (ArcMap sent a map directly to the plotter without interim steps.) There was no scale bar on the map. It shouldn't have been needed for this. Did something happen to the map scale when QGIS output the map to PDF? Could the size of the image on the pdf page have been adjusted manually or otherwise when being sent to a plotter with 42" paper? Could the image have been distorted horizontally differently from vertically? For the life of me, I cannot trial-and-error guess at a scale to enter. I've gone through dozens of new 8.5" x 11" test maps trying to guess the correct scale. Any ideas? Thank you all - John A. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Fw: Did scale change outputting to PDF?
Hi, Jochen. Your suggestion sounds do-able; I'll play around with it and see if I can sort it out. I've got some digital calipers around here somewhere :) What I'm hearing is that the process of converting both the base map (and yes, I did create it in QGIS) and the parcel maps into PDF will distort the scale. (And that a print shop might compound the problem by manually fitting the source file to the printable area. Yes?) A question then is why didn't the PDF conversion distort them all the same way, to the same degree? The base maps are done now and I couldn't afford to do them again no matter what, so they are what they are. Going forward, is there an export option in Print Layout that will not distort the scale of the parcel maps? I am so relieved that someone has an explanation for this! - John A. - Forwarded Message - From: j.hu...@post-ist-da.de To: "qgis-user@lists.osgeo.org" Sent: Thursday, May 27, 2021, 03:33:12 AM EDTSubject: Re: [Qgis-user] Did scale change outputting to PDF? Hi John, as I understand it, you created the base map in QGIS. If you use the measure tool in QGIS to get the distance between two distinct features in the map (e.g. road intersections) and then measure the same distance on the printed base map with a ruler, it should be possible to calculate the scale. Maybe use two distances, one aligned more or less horizontally and one vertically, to check if the scaling is proportional. As Andreas pointed out, it is probably a problem with the settings when the PDF was printed. In my experience it is a good idea to go to print shops usually working for architects and engineers since they are familiar with the importance of scaling (for advertising etc. it is more important that the whole content is printed, so that scaling might be used to fit the output to the printable area without potential cropping). You can print directly to a plotter in QGIS if you have access to the device, avoiding the PDF detour. EPSG 2264 should be fine. Units should be US feet. Regards Jochen Am 27.05.21 um 07:15 schrieb John Antkowiak: Hi. This plan was too simple to fail - but it failed. The charity whose project this is needed a large (that is... massive) paper wall map on which to plot and rethink its delivery driver assignments. Both drivers and delivery addresses are subject to change from week to week but it's not a pizza delivery; this is a regular run to supply people in a bad way. So the plan was to print the base map (roads and road names and county boundaries only) and then print 8.5 x 11 address maps with parcel data and orthos. That way, the base maps don't change but the physical parcel layer is flexible. (On top of that is a third paper layer indicating which drivers go where so someone can stand back and take in the whole picture graphically. Not a cutting-edge state of the digital art solution, but not everyone is cut out for that. It is what it is.) In order for this to work, the parcel maps have to be the same scale as the base map. Which they were... in QGIS. We have to convert all the maps to PDF to print them, and we had to send the base map PDFs to FedEx/Kinkos to print the 9 map grid panels at 42" by 62" each. When we got the big base maps up on the wall, we discovered the scale did not match the 8.5" x 11" parcel maps output to PDF and printed from home. It's not off by a lot, but it's enough to be painfully obvious from a single standard size sheet of paper. I don't know how to reverse engineer the big map scale precisely enough to enter a new scale number in the QGIS Print Layout. I didn't foresee it because this never would've been a conceivable scenario at the engineering firm where I picked up my meager GIS skills. (ArcMap sent a map directly to the plotter without interim steps.) There was no scale bar on the map. It shouldn't have been needed for this. Did something happen to the map scale when QGIS output the map to PDF? Could the size of the image on the pdf page have been adjusted manually or otherwise when being sent to a plotter with 42" paper? Could the image have been distorted horizontally differently from vertically? For the life of me, I cannot trial-and-error guess at a scale to enter. I've gone through dozens of new 8.5" x 11" test maps trying to guess the correct scale. Any ideas? Thank you all - John A. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___
[Qgis-user] Fw: Did scale change outputting to PDF?
Hi, Andreas. I'm not entirely conversant in the CRS. I do understand the basics. All layers use the same CRS, NAD83 / North Carolina (ftUS), EPSG:2264. I know that the NAD variant is State Plane but I'm not familiar with EPSG. - John A. - Forwarded Message - From: Andreas Neumann To: John Antkowiak Cc: QGIS User List Sent: Thursday, May 27, 2021, 02:43:34 AM EDTSubject: Re: [Qgis-user] Did scale change outputting to PDF? Hi again John, Another thing: what projection (CRS) did you use? Not all CRS are suitable for printing to scale - esp. the Web Mercator projections are often not suitable. Greetings, ANdreas On 2021-05-27 08:20, Andreas Neumann wrote: Hi John, A very common error when printing PDF maps (regardless of the software that generated the PDF), is that the print shop scales it down to fit the "printable" area. Then you end up at somewhere around 95% (plus / minus) a bit The PDF viewers (at least the Acrobat one) has a setting to print at 100% (but this is not the default) - it has to be done consciously. However, this normally scales uniformly, not separately for width and height. On the topic of "base maps": Can you explain what source/mechanism for "base maps" you used? Are you refering to "tiled" maps, perhaps consumed through the OpenLayers plugin? This plugin is a known to be a source of error for misalignments and the plugin should be avoided. Even if you didn't use this plugin, I have to say that tiled base maps (e.g. consumed by the quick map services plugin or otherwise) are usually not suited for printing as their resolution is optimized for screen viewing. Printing these tiles would result in disappointing quality. Greetings, Andreas On 2021-05-27 07:15, John Antkowiak wrote: Hi. This plan was too simple to fail - but it failed. The charity whose project this is needed a large (that is... massive) paper wall map on which to plot and rethink its delivery driver assignments. Both drivers and delivery addresses are subject to change from week to week but it's not a pizza delivery; this is a regular run to supply people in a bad way. So the plan was to print the base map (roads and road names and county boundaries only) and then print 8.5 x 11 address maps with parcel data and orthos. That way, the base maps don't change but the physical parcel layer is flexible. (On top of that is a third paper layer indicating which drivers go where so someone can stand back and take in the whole picture graphically. Not a cutting-edge state of the digital art solution, but not everyone is cut out for that. It is what it is.) In order for this to work, the parcel maps have to be the same scale as the base map. Which they were... in QGIS. We have to convert all the maps to PDF to print them, and we had to send the base map PDFs to FedEx/Kinkos to print the 9 map grid panels at 42" by 62" each. When we got the big base maps up on the wall, we discovered the scale did not match the 8.5" x 11" parcel maps output to PDF and printed from home. It's not off by a lot, but it's enough to be painfully obvious from a single standard size sheet of paper. I don't know how to reverse engineer the big map scale precisely enough to enter a new scale number in the QGIS Print Layout. I didn't foresee it because this never would've been a conceivable scenario at the engineering firm where I picked up my meager GIS skills. (ArcMap sent a map directly to the plotter without interim steps.) There was no scale bar on the map. It shouldn't have been needed for this. Did something happen to the map scale when QGIS output the map to PDF? Could the size of the image on the pdf page have been adjusted manually or otherwise when being sent to a plotter with 42" paper? Could the image have been distorted horizontally differently from vertically? For the life of me, I cannot trial-and-error guess at a scale to enter. I've gone through dozens of new 8.5" x 11" test maps trying to guess the correct scale. Any ideas? Thank you all - John A. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Fw: Did scale change outputting to PDF?
Thank you, Andreas - I thought there must be a PDF error. I didn't use any tiling plugin but rather created my own polygon for that. Other than the scale issue, I'm very pleased with the print quality. So if the scale error is proportional I should be able to eventually home in on the correct scale to use. That's promising, and I appreciate your letting me know. Thank you very much! - John A. - Forwarded Message - From: Andreas Neumann To: John Antkowiak Cc: QGIS User List Sent: Thursday, May 27, 2021, 02:27:20 AM EDTSubject: Re: [Qgis-user] Did scale change outputting to PDF? Hi John, A very common error when printing PDF maps (regardless of the software that generated the PDF), is that the print shop scales it down to fit the "printable" area. Then you end up at somewhere around 95% (plus / minus) a bit The PDF viewers (at least the Acrobat one) has a setting to print at 100% (but this is not the default) - it has to be done consciously. However, this normally scales uniformly, not separately for width and height. On the topic of "base maps": Can you explain what source/mechanism for "base maps" you used? Are you refering to "tiled" maps, perhaps consumed through the OpenLayers plugin? This plugin is a known to be a source of error for misalignments and the plugin should be avoided. Even if you didn't use this plugin, I have to say that tiled base maps (e.g. consumed by the quick map services plugin or otherwise) are usually not suited for printing as their resolution is optimized for screen viewing. Printing these tiles would result in disappointing quality. Greetings, Andreas On 2021-05-27 07:15, John Antkowiak wrote: Hi. This plan was too simple to fail - but it failed. The charity whose project this is needed a large (that is... massive) paper wall map on which to plot and rethink its delivery driver assignments. Both drivers and delivery addresses are subject to change from week to week but it's not a pizza delivery; this is a regular run to supply people in a bad way. So the plan was to print the base map (roads and road names and county boundaries only) and then print 8.5 x 11 address maps with parcel data and orthos. That way, the base maps don't change but the physical parcel layer is flexible. (On top of that is a third paper layer indicating which drivers go where so someone can stand back and take in the whole picture graphically. Not a cutting-edge state of the digital art solution, but not everyone is cut out for that. It is what it is.) In order for this to work, the parcel maps have to be the same scale as the base map. Which they were... in QGIS. We have to convert all the maps to PDF to print them, and we had to send the base map PDFs to FedEx/Kinkos to print the 9 map grid panels at 42" by 62" each. When we got the big base maps up on the wall, we discovered the scale did not match the 8.5" x 11" parcel maps output to PDF and printed from home. It's not off by a lot, but it's enough to be painfully obvious from a single standard size sheet of paper. I don't know how to reverse engineer the big map scale precisely enough to enter a new scale number in the QGIS Print Layout. I didn't foresee it because this never would've been a conceivable scenario at the engineering firm where I picked up my meager GIS skills. (ArcMap sent a map directly to the plotter without interim steps.) There was no scale bar on the map. It shouldn't have been needed for this. Did something happen to the map scale when QGIS output the map to PDF? Could the size of the image on the pdf page have been adjusted manually or otherwise when being sent to a plotter with 42" paper? Could the image have been distorted horizontally differently from vertically? For the life of me, I cannot trial-and-error guess at a scale to enter. I've gone through dozens of new 8.5" x 11" test maps trying to guess the correct scale. Any ideas? Thank you all - John A. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Did scale change outputting to PDF?
Hi. This plan was too simple to fail - but it failed. The charity whose project this is needed a large (that is... massive) paper wall map on which to plot and rethink its delivery driver assignments. Both drivers and delivery addresses are subject to change from week to week but it's not a pizza delivery; this is a regular run to supply people in a bad way. So the plan was to print the base map (roads and road names and county boundaries only) and then print 8.5 x 11 address maps with parcel data and orthos. That way, the base maps don't change but the physical parcel layer is flexible. (On top of that is a third paper layer indicating which drivers go where so someone can stand back and take in the whole picture graphically. Not a cutting-edge state of the digital art solution, but not everyone is cut out for that. It is what it is.) In order for this to work, the parcel maps have to be the same scale as the base map. Which they were... in QGIS. We have to convert all the maps to PDF to print them, and we had to send the base map PDFs to FedEx/Kinkos to print the 9 map grid panels at 42" by 62" each. When we got the big base maps up on the wall, we discovered the scale did not match the 8.5" x 11" parcel maps output to PDF and printed from home. It's not off by a lot, but it's enough to be painfully obvious from a single standard size sheet of paper. I don't know how to reverse engineer the big map scale precisely enough to enter a new scale number in the QGIS Print Layout. I didn't foresee it because this never would've been a conceivable scenario at the engineering firm where I picked up my meager GIS skills. (ArcMap sent a map directly to the plotter without interim steps.) There was no scale bar on the map. It shouldn't have been needed for this. Did something happen to the map scale when QGIS output the map to PDF? Could the size of the image on the pdf page have been adjusted manually or otherwise when being sent to a plotter with 42" paper? Could the image have been distorted horizontally differently from vertically? For the life of me, I cannot trial-and-error guess at a scale to enter. I've gone through dozens of new 8.5" x 11" test maps trying to guess the correct scale. Any ideas? Thank you all - John A.___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] How to create a QGIS grid but not the usual way
Hi, Thayer. Again, exactly what I wanted to know; you are most kind. Thank you too for advising me about sending a reply to the whole list. I hadn't realized I wasn't doing that. Thank you all who commented on any of several questions I had. This project has come to a successful, rapid conclusion because of the tips you all offered. Have a great day! - John A. On Sunday, May 16, 2021, 05:59:52 PM EDT, Thayer Young wrote: Hi John, You can prevent the warning about no spatial index by creating the index for each layer using the "Create Spatial Index" processing algorithm. Or you can just ignore the warning. If you are certain of the EPSG code for your layers you can use the "Assign Projection" processing algorithm. EPSG 2264 sounds like a good candidate. Reprojecting to UTM Zone 17N should be good also EPSG:26917. You can find both of these tools by entering their names into the search bar at the bottom left of the main QGIS window or at the top of the Processing Toolbox panel. If you have roads and county boundary shapefiles in the same EPSG 2264, you should be able to clip your roads (input) with your county boundary (overlay) using the Clip tool. If you want your roads to overlap the county boundary try reprojecting your Extent polygon to 2264. Another possibility is that there are invalid geometries. You may want to try the Check Validity, Fix Geometries, and or v.clean tools to find and correct invalid geometry. You may also be able to get more information about what is going wrong from the messages panel. There is a toggle button for it in the bottom right of the main QGIS window. You should be able to get a good pdf converter for free or low cost. So you can convert image files and compile them into a single pdf. -Thayer PS Please remember to send responses to the entire mailing list. - Forwarded Message - From: John Antkowiak To: Thayer Young Sent: Saturday, May 15, 2021, 11:06:38 PM EDTSubject: Re: How to create a QGIS grid but not the usual way Hi, Thayer. I may have to ask for a follow-up explanation. I do apologize. I re-projected the file and each layer separately. Now the GUI tells me, as anticipated, that the CRS is EPSG:2264. (Scrolling down through the list of available systems to use, I found this one - which is further identified as NAD83/NC (ftUS) - before I found the UTM choices. So I selected it.) Each layer matches, so that part went as expected. Then I saved the project and restarted QGIS to rule those variables out when the next step failed. Now when I clip the data to a new shapefile, I see the following error: "No spatial index exists for input layer, performance will be severely degraded." I received the same error before re-projecting everything. This happens with both layers I'm trying to clip: the county boundary and the streets. And when I try to add the resulting shapefiles to a new, blank map project, they fail to load. "File unsupported" or words to that effect. I suspect (but I don't know) the problem is that I'm trying to clip the two State-government layers against the grid polygons (rectangles) I created, even though I was able to save that layer as a valid shapefile with a recognized CRS matching that of the State layers. If I have to use UTM instead, how do I know whether it's Zone 16 or 17? (From my professional experience years ago - I have a decent amount of experience but no formal GIS education so I'm no expert regarding projection systems - I thought I remembered the dividing line between the two being in Florida.) Alamance County is centered east to west in the northern half of North Carolina. This step was necessary because I find I can't create an atlas as a PDF and I don't have Adobe to create one from jpegs. I can export a single map to PDF, but not an atlas unless there's a plugin I can go obtain. So I'm trying to create 9 separate maps by clipping the total extent by the gridlines you helped me create (very effectively I might add - thank you again!) Again, both thanks and apologies... - John A. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] How to create a QGIS grid but not the usual way
Hi. I'm new to QGIS. I've been up all night reviewing the Training Manual and watching tutorial videos looking for someone to address my situation. I'm overtired and I'm sure I'm missing something obvious. I'm trying to create a large-format paper wall map to show all the roads in my county, and I have to create an atlas to do it. For sake of this question, let's assume the county is approximately 19 miles east-west and approximately 28 miles north-south. The key word here is approximately - and I suspect this task requires precision that I don't know how to find. All the lessons for creating grids from which the atlas will be generated instruct me to do it the same way: specify the desired horizontal and vertical intervals. That's not what I want. What I want is to divide the extent by three, whatever interval that happens to be. And I can't figure out precisely the total dimension, in miles, of the map extent. In case this is relevant: the data layers are projected in NAD83 / North Carolina (ftUS) but the QGIS GUI at the bottom right says "Unknown CRS." I created a layer for this exercise - don't ask me to explain how I did it - whose only feature is a rectangle covering the area to be divided. This layer I call "Extent." I try to use the Measure tool to get the exact east-west distance of the polygon. BUT. I have to manually select the start and end points, and I have no confidence that the points I'm selecting precisely match the limits of the polygon because when I measure the north and south horizontal lines, I get two different values. It's a rectangle. The values ought to be the same. Am I going bout this all wrong? How do I create this 3 x 3 grid? Thanks - John A.___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Fw: How to change Map resolution in QGIS Print Layout
Hi. I cannot find an answer to this in the QGIS User Guide or online tutorial videos, and I'm a very inexperienced user. My datasets are linked below. They're from the State of North Carolina and consist of 1) all the streets in the State, and 2) all the county boundaries. I clipped each layer so that I'm working with the streets in Alamance County only. I use the "StreetName" attribute to label the layer. I need to create a paper wall map to help a charity plan its delivery routes. I have no innate sense exactly how big the map has to be; I'm starting with an assumption of a 60" roll of paper. (I've already had to rule out a commercial or purchase of a predesigned product. Doing it myself will cost me probably ten hours, which I can spare, but save nearly a thousand dollars that I can't.) In my Print Layout, I set the paper size to 60" wide by 115" high. (It would be nice if I could change the interface ruler units from mm to inches, but I don't see how. This would help me ensure the desired margin.) I add the map and adjust its scale to fit the entire county as large as possible on the layout page. I hope I'm expressing the scale correctly, but I believe the smaller the scale number, the closer-in the map appears. The closer I zoom in, the more street names should appear. I would prefer that all street names are visible. But here's the first challenge. The Print Layout window acts as a preview of the final printed product, and what it shows me when viewed at 1:1 scale is not what I want to see. All the vector lines and all the labels are so pixelated that they're almost illegible. It makes no difference what the map scale is, because the size of the labels and their resolution doesn't change with the map scale. I tried going back to the source map and adjusting the label font size from the default (10) to 12, but it didn't change the outcome. It only yielded bigger pixelated illegible labels. (I exaggerate; they're not illegible they're just very difficult to read, almost to the point of rendering the whole exercise moot.) I tried adjusting the output dpi in the Print Layout to 500 dpi, but I think all that does is make the pixelated labels more sharply pixelated. The preview didn't change at all. A screen capture is attached. Once I solve that problem, I suspect I'm going to find that a scale of 18,000 - which allows the entire county to be shown on one page without losing any vector data - isn't close enough to display enough of the street names. I'm going to have to create map panels, which adds a level of complexity to my learning curve. Any insights on this situation would be most appreciated. Have a good day - John A. The two datasets are found here:https://connect.ncdot.gov/resources/gis/Pages/GIS-Data-Layers.aspx Download the layers titled "Road Characteristics Arcs Shapefile Format" and "County Boundary Shoreline" to reproduce exactly what I see. Clip them as described above. ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
Re: [Qgis-user] QGIS Download
Hi, Finbar. I installed the same version only a few weeks ago - my first experience with QGIS. It put a shortcut on my desktop linked to "C:\Program Files\QGIS 3.2\bin\qgis-bin.exe." I know these are the first places you looked, but if your desktop is crowded I suppose you might not see it. It's a bit like a green 'Q.' It also installed a raster managing program called GRASS - which I was not expecting - also with a shortcut on the desktop. For whatever that's worth... John A. On Tuesday, July 31, 2018, 11:21:43 AM EDT, GILLEN Finbar wrote: Hi, I have got IT to download the QGIS 3.2 ‘Bonn’ installer program onto my PC, when I run the installer it states that QGIS has installed successfully in my c drive however I cannot find it. I have re started the PC and reinstalled the program and still is nowhere even though it states it has installed successfully. Has anyone came across this issue before? Regards Finbar Finbar GILLEN Underwriting Performance Analyst Pricing & Underwriting Department AXA Insurance dac Wolfe Tone St, Dublin 1 T: +353 1 471 1377 E:finbar.gil...@axa.ie * The contents and any attachments of this electronic mail message are confidential and intended only for the named addressees. Dissemination, forwarding, publication or other use of the message or attachments by any unauthorised person is strictly prohibited. Unless stated to the contrary, any opinions expressed in this message are personal and may not be attributed to AXA Insurance dac or any member of the AXA Group of Companies. AXA Insurance dac is regulated by the Central Bank of Ireland. For business in Northern Ireland, AXA Insurance dac is authorised by the Central Bank of Ireland and subject to limited regulation by the Financial Conduct Authority. Details about the extent of our regulation by the Financial Conduct Authority are available from us on request. AXA Insurance dac is a private company limited by shares, registered in Ireland number 136155. Registered Office Wolfe Tone House, Wolfe Tone Street, Dublin 1. "AXA Supporting Road Safety in Ireland" Internet e-mails are not necessarily secure. AXA Group does not accept responsibility for changes made to this message after it was sent. To help promote the use of electronic documents and to be kinder to the environment, please consider whether you really need to print this email. * ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
[Qgis-user] Brand new user - never heard of QGIS. Where can I find system requirements?
Hi. I used to work with ESRI ArcMap tools as a self-taught mapping analyst, but I haven't looked at mapping platforms in over ten years. Now I have a rather simple project involving boundary vectors for political districts in North Carolina. I need to plot several pieces of information. My system resources are limited. I have no doubt QGIS can handle the task, but is it overkill? Will something simpler do? I need to produce informative .jpgs for email distribution or perhaps web publishing for access by a network of home users. This is not for corporate use. What system requirements must I meet, for downloading and running QGIS? I have an ASUS R510LA notebook with about 370 GB of available memory. Its processing specifications are shown in the attached image. I will also need help finding and using data repositories. Will I have to maintain data sets locally? I don't expect to need raster graphics, but I will need vector and point layers that should be available publicly. This is also my first experience with mailing lists, so I do not understand its concepts yet. I will learn quickly. Thank you for your help! ___ Qgis-user mailing list Qgis-user@lists.osgeo.org List info: https://lists.osgeo.org/mailman/listinfo/qgis-user Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-user
