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Grainy renderings despite high DPI settings


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I am rendering an exterior landscape for a bridge redesign project and despite high (300) DPI settings everywhere I can (VW default, sheet settings, and camera when used), the renderings still come out extremely pixelated. The quality is noticeably low when opened in Photoshop, for example. At 1"=10' on an AnsiD sheet, I would hope for a crisp render. I know Vectorworks Landmark can do this. What am I doing wrong?

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I used custom renderworks settings with all fields set to very high. Anti-aliasing is turned off since after an hour there was almost no progress with the render. Sheet DPI and the camera DPI are both set to 300. Also the scale is 1"=50' on an AnsiD sheet. See attached images for the entire rendering and zoomed in details of the pixelated wasteland.

1489027383_ScreenShot2021-07-14at12_22_02PM.thumb.png.577f96223d6fee5653855769a8937dee.png 

Screen Shot 2021-07-14 at 12.22.14 PM.png

Screen Shot 2021-07-14 at 12.22.34 PM.png

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That's not pixellation, per se, but a lack of Anti-Aliasing. You'll have to turn that back on in order to smooth out the interpolation of pixels.

 

There might be other ways to reduce your render time in return. Could you post screenshots of your custom render settings, or post the file?

 

Also, what is the size of your viewport? (width is the ΔX field in the OIP). Scale isn't really a useful parameter here.

 

The number of pixels in a rendering is a factor of only two things: Sheet DPI and Viewport size.

 

 

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I have altered the renerworks settings to include anti-aliasing set to very high with all other fields set to medium. So far what little has rendered doesn't look too great. The dimensions of the viewport are approx. 1'6"x1' in the OIP. I am not familiar with viewport dimensions, only setting the scale to change size. It looks like it would be a little over 34"x22" on the page, but the OIP dims say different. Can someone walk me through this? Thanks for everyone's help so far!

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1 hour ago, TallulahOrcel said:

I have altered the renerworks settings to include anti-aliasing set to very high with all other fields set to medium.

 

"High" Anti-Aliasing is often good enough. "Very High" takes forever.

 

Take a look at this guide to RW styles, which includes some of my suggestions for quality levels, though of course it varies from person to person and it depends what your intended output is.

 

And yes, your Viewport is indeed 12x18". So at 300 dpi that's approx 3600 x 5400 px, or about 19,440,000 pixels total. That's somewhere around a 6k image.

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I don't understand how my viewport is 12x18 when it fills an AnsiD sheet at 50 scale. How can I alter the dimensions of a viewport, and would this perhaps improve the quality of the image? I am fairly familiar with creating viewports, but have never dealt with the dimensions thereof unless I'm using a polygon to create the viewport. 

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Could you post a screenshot of your entire sheet layer? Hard to tell without seeing what you're seeing. All I know is that your OIP screen grab shows the viewport is ~12x18". Also keep in mind measurable scale does not exist when in perspective.

 

 

You can change the viewport size by typing in a desired width into the ΔX field. A larger viewport has more pixels, so in a sense that can be though of as higher quality.

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What we are seeing from what you posted, the viewport is 12x18" and is somehow being expanded to  22"x34" on the sheet layer. Since the viewport is expanded to about double the actual size, that means that you are not getting 300 dpi, but something closer to 150. That might explain part of the graininess.

 

But if you resize the viewport so it is truly 22x34, and set your DPI to 300, you are going to extend your render times by about a factor of 4.

 

For the scaling problem, check two places.

1. Page Setup:Printer Setup:Page Attributes:Scale

 

image.png.5e2e7fefce0df69d7dae1075c9ca415f.png

 

2. Page Setup:Printer Setup:Vectorworks:Scale

 

image.png.024a08c0834ff2c1fbdd4185c0e7e0b6.png

 

 

Also, what is the final use of this output? For a 22x34 drawing, it is unlikely that anyone will be close than about 2' from the drawing and likely to be 4'-6' away if it is hung on a wall. Considering how long it will take to render that at 300dpi, do you really need it?

 

Try a quick test. Do an 8.5x11 rendering at 300 dpi and at 150 (or 200) dpi. Hang both on the wall and stand 3' away. Can you see a difference?

 

 

 

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On 7/14/2021 at 4:12 PM, Andy Broomell said:

FWIW, I render most things at 16" wide, at 120 or 240dpi (see chart below I made for reference; if using 16:9 camera aspect ratio which is common in TV).

 

Viewport_Size_Chart_Andy_Broomell.thumb.png.8f128341a0456479291e7342d603a70b.png

 

At the end of the day all the numbers are arbitrary, but making certain numbers consistent can help with one's understanding and expectations of quality. Since I always make my Viewports 16" wide, for example, I have a good idea in my head of what various DPIs look like. But you can choose different numbers.

 

BTW, I should clarify that my post above is referring to renderings whose end result is an image, such as a standalone jpeg or png, perhaps one you take into Photoshop afterwards or send in an email as an image. 

 

As opposed to an viewport ON a drafting plate, such as a 3D view of something, then that's a slightly different story since the printed size on the paper is a constraining factor.

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On 7/14/2021 at 4:12 PM, Andy Broomell said:

FWIW, I render most things at 16" wide, at 120 or 240dpi (see chart below I made for reference; if using 16:9 camera aspect ratio which is common in TV).

 

Viewport_Size_Chart_Andy_Broomell.thumb.png.8f128341a0456479291e7342d603a70b.png

 

At the end of the day all the numbers are arbitrary, but making certain numbers consistent can help with one's understanding and expectations of quality. Since I always make my Viewports 16" wide, for example, I have a good idea in my head of what various DPIs look like. But you can choose different numbers.

Really, @Andy Broomell this chart makes my decision tree for renders so much more efficient. Thanks for the share.

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