Author Topic: Image size is different from Render settings  (Read 1420 times)

2021-07-31, 20:34:58

Mettigel Hawaii

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Hi,

I was trying to get an A2 image, so I chose 59,4cm*42cm in the render settings when I startet my cinema scene. At first I had 70dpi for testing, before I did the final render I changed to 200dpi. I saved my image as PNG but somehow it came out about double the size I wanted it to be and I had to scale my render to fit it into my presentation layout.
Does somebody know what I did wrong there?

Best regards, Mettigel Hawai

2021-07-31, 22:03:05
Reply #1

burnin

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Just got a bit confused... NP, a beginer's mistake.
Simply understand & don't 'mentally' mix mediums (its resolutions and other physical properties).
dpi (dots per inch) / term used in 2D printing where density, detail is dynamic.
ppi (pixels per inch) / term for display resolutions where density, detail is static and constant.
...


2021-08-01, 14:05:06
Reply #2

Mettigel Hawaii

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I don't know which settings caused the larger image, thats why I pointed out what I changed in the settings, which was dpi, since I thought that dpi changes lead to higher quality in for my final render image.

2021-08-01, 16:04:21
Reply #3

burnin

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As you can observe under Render Settings/Output when you use 'Print' presets, then change dpi below it it shows how your rendered image res./ size changes (in pixels) while "Print size stays static" (cm)... so again, their UI terminology is a bit misleading, causing confusion.  ;)


2021-08-02, 10:40:07
Reply #4

Philw

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I don't know which settings caused the larger image, thats why I pointed out what I changed in the settings, which was dpi, since I thought that dpi changes lead to higher quality in for my final render image.

Guessing you are aiming for a final print 100% size of 200dpi - you only need to worry about the final pixel count as per @burnin - ignore the dpi - I always aim for 300dpi because I'm old. You can always just use an online calculator too to give you the pixels you need https://www.omnicalculator.com/other/pixels-to-print-size

2021-08-02, 11:13:52
Reply #5

Beanzvision

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2021-08-02, 15:46:10
Reply #6

Mettigel Hawaii

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Thanks for all your answers.
So if I need a PNG image  for my Indesign layout (59,4*42cm) I dont need to change the dpi at all? Is there another way to adjust render quality settings then? So for example if I want to go for a quicker test render.
So only for the case I want to print my image DPI becomes relevant



2021-08-03, 07:10:52
Reply #7

bnji

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You can duplicate your current render settings, give it another name, lock the aspect ratio, and then reduce the size.
Once you're ready to do your final render, simply switch/activate to your previous settings, and that's it.
I hope it helps.
Regards.

2021-08-03, 13:06:03
Reply #8

burnin

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And there's a setting  which always keeps interactive preview image ratio & size under value set.

Preferences > Corona > Interactive rendering > Maximum resolution (long side)

2021-08-09, 14:03:35
Reply #9

BigAl3D

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I have extensive experience in print and digital mediums. It is best to only think about the pixels when rendering in C4D and not inches or centimeter. This can get confusing for people not very experienced in resolution. Just think pixels. It will simplify things. I'll explain below using the standards here in the States. This will sound confusing at first, but it will all make sense when you get it.

When a client asks me for an image or graphic, the first question I ask is "What are you using it for and how large with the end size be?"

If the reply is "For a magazine ad. The image will be 6"w x 4"h. (always clarify the width and height since many will give you the height number first).
I know most publications ask for 300dpi (some are lower or higher, just ask them or a specification sheet). 300dpi is a good starting point and will be good for most applications. So it's simple math from there. 6" x 300 = 1,800 pixels and 4" x 300 = 1,200 pixels. So for every inch, you have 300 pixels. See how that works? So this render will be 1,800 x 1,200 pixels at 72. We will change this below.

Assuming you're using this image for a print layout, you should take one more step with it. If you import the render into InDesign as-is, it will appear approx 3 times larger than you need since your render is set to 72dpi. You have two options. First is scale it back down to the final size in InDesign (or whatever app). This will effectively crunch more pixels into a smaller space, which "increases" the resolution at the smaller size. The best thing to do is open the image in Photoshop. Go to Image --> Image Size. This step is VERY important. UN-check the Resample option. Turn it OFF. Now change that resolution right above that to 300 pixels/inch. Boom. Now when that image is placed in your layout, it will show at the proper size and resolution. This also helps the designer see that they should not scale the image much at all since the resolution begins to drop as it is scaled. You could always render larger so you can give a designer more flexibility. You might also ask if they need the final image as RGB or CMYK. If your image will be give to a designer, they can handle that. If it's to someone that doesn't know, better to provide it the final color space. Many printers convert images on their end to what they need, but your never know.


If the reply is "For a PowerPoint presentation that will be shown on our HD screen or projector at a meeting. The image will be full screen.
I know that everything on-screen is 72dpi. Set C4D's output to 1,920 x 1080 which is standard HD. Personally, I wouldn't worry about 4k or anything like that. The image will scale very nicely to 4k on a screen and especially a projector. If you want to be safe, then set it to 3840 x 2160. If you're rendering an animation, this can make a huge difference in time.
Assuming they have decent technology and are not running Windows Vista or Mac OS 9 on really old PCs, then the client should be happy with your file.


I don't know the standard dpi settings for using centimeters, but I see an A2 image is 16.5" x 23.375" or 4,950px X 7,013px.

Sorry for the long post, but this is where most newer designers stumble and make the wrong size graphic. Please ask if you're confused about something. I know it took me a while to understand it completely.