Lines in Render

W

wolfcheck

0
Lines in Render

Why am I getting these lines in my render? The texture is an imported solid color .jpg. I've got my radiosity tag error under 0.04 and increased the amount of samples in the Radiosity tag because I was getting dark splotches. I don't ever remember my textures doing this. Any thoughts?
 

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But I will tell you this. I have two versions of Cheetah. The latest version is on my newer Mac Mini and the earlier version (5.6???) is on my older Mac Mini. I usually create in the older version and then copy the file over to the newer version to render it, because it's faster. A render on my old version does not have the lines. Maybe I corrupted something moving it over?
 
wolfcheck said:
What do you mean? How are you going to look into the file?
Click to expand...
Well you can compress and upload it or share a link or make a screenshot of the 3d view without texture (wireframe). To me it seems like there´re not connected polygons. If the lines are intentional you might increase the Min.Samples at the render settings of the camera.

Cheers
Frank
 
My immediate suspicion is doubled geometry or a very thin object with front and back faces intersecting.

C3D treats all polygons as two-sided and if two polygons are exactly coincident then it's random which one a ray (Cheetah) or photon (Falcon) will hit and also random whether it will be illuminated.

Another possibility is a source bitmap with slight misalignment of UVs _or_ transparent edges.
 
Well, I fixed it. I got to thinking and had my suspicions about the textures. I imported flat color .jpgs so I could get the colors just right. So I enlarged them in Photoshop, resaved them and reimported them into Cheetah and retextured everything. All the lines are gone! Go figure! I'll post a finished render.
 
:smile: Thanks wolf check & Swizl

Quite often I am working with Transparent images; however when it comes to non-transparent images:

1. Does one format produce a largely noticeable better resolution than the other?
2. In the long run would it affect the "umph" (for lack of a better word to describe the power needed) needed to render an animation?

I know at one time tiffs were considered the best resolution however they are costly "ram wise" (for lake of knowing how to express it).

If someone could also let me know better words to express what I'm trying to describe it would be appreciated. :rolleyes: I'm rolling my eyes at me for not being able to find the correct words. However - I think my words are more fun anyhow.

Thanks

My Best
Jeanny
 
wolfcheck said:
I always use .jpegs. I've never used png. Just preference, I guess. I finally put a copy of the render in the gallery.
Click to expand...

It's not a preference, it's a decision ;-)

PNG — losslessly compressed (no surprises, like weird artifacts), and alpha channel support.

JPEG — lossily compressed (which usually means smaller files) which also means every time you make an edit and save it, there's a generation loss (like copying a VHS tape to another VHS tape), and in particular, because the compression relies on a model of human perception, you're also giving up a lot more quality in places a person usually won't notice (like darker tones, and especially dark blues). The problem is that a texture is not a final delivery image, so you're going to randomly degrade your overall image in ways that can't easily be predicted.

E.g. suppose you use a JPEG transparency map, and you want to make a glass pane look a little dirty, but it turns out this means using a source bitmap that's very dark. JPEG doesn't care about details in dark, so the transparency channel ends up having horrible artifacts which are obvious because the final image created isn't very dark. Transparency and reflection maps are often lots of shades of dark, and that's something JPEG will absolutely butcher if you're not careful.

So, no it's not a preference, it's a decision to trade storage space (which is very, very cheap) for quality.
 
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Actually, it is a preference. It's what I'm used to using. I've never used .png, didn't know anything about it. Used .tiff a lot when I was working in printing, but after I left that, all the files I worked with were Photoshop and Illustrator and mostly Illustrator files imported into Photoshop. Jpegs were just easier for me to work with. I was familiar with them. Might have to check into the .png format though.
 
If you didn't know about PNG it's not even a preference ;-)

TIFF, like PNG, is losslessly compressed, but in general TIFF files are much bigger than PNG files containing the same information. That said, TIFF includes support for images PNG does not (e.g. 16 bpc).

Again, understanding what different files actually are, and are for, is pretty important. JPEG is intended as a delivery format. It's not intended for work product — just as an audio engineer wouldn't store recordings in MP3, or a writer wouldn't use PDF for a half-written novel, or a programmer wouldn't store programs in .o files, an artist shouldn't use JPEG for anything other than delivery of final output to a consumer.

Now, there are reasons why you might start with a JPEG file — e.g you might be working with a photo from a camera (or phone) that has no RAW support. But if you're going to make any changes to it, you'd want to use a lossless format, such as PNG, PSD, TIFF, etc. (to avoid generation losses). When you're using the image as part of a pipeline, you definitely want to avoid lossy formats based on a human perceptual model (like JPEG).
 
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Here's my rules: Don't use a lossy compression until the last step. Lossy compression throws stuff away.
Keep a copy of the file from before you made the jpeg.

That being said, if don't work directly with the client, and the "bosses"
take the job orders, you will get jpegs even if they are told not to do that.

They want to keep the job, and won't tell a client to go get the right stuff for fear of loosing them.

Fallback Rule: Since you have to work with jpegs sometimes, don't re-save it as a jpeg until the last step.

Remember with jpegs the compression level is adjustable,
and you may not know to what extent it has been compressed.

​
 
ZooHead said:

Here's my rules: Don't use a lossy compression until the last step. Lossy compression throws stuff away.
Keep a copy of the file from before you made the jpeg.

That being said, if don't work directly with the client, and the "bosses"
take the job orders, you will get jpegs even if they are told not to do that.

They want to keep the job, and won't tell a client to go get the right stuff for fear of loosing them.

Fallback Rule: Since you have to work with jpegs sometimes, don't re-save it as a jpeg until the last step.

Remember with jpegs the compression level is adjustable,
and you may not know to what extent it has been compressed.

​
Click to expand...

Exactly.

I remember in the "good old days" you'd get a request from a client to do something with their logo, so you'd ask for the original file… Puzzled look. Then you'd ask for the EPS. Puzzled look. Then you'd ask for a bromide. At this point, if you're lucky, you got a bromide (high resolution output from a linotron or similar), otherwise you got a piece of letterhead and ended up recreating the logo yourself in Illustrator.

Then, when you handed the work back with a copy of their logo in illustrator format, they'd wonder WTF they needed the disk for…
 
podperson said:
Exactly.

I remember in the "good old days" you'd get a request from a client to do something with their logo, so you'd ask for the original file… Puzzled look. Then you'd ask for the EPS. Puzzled look. Then you'd ask for a bromide. At this point, if you're lucky, you got a bromide (high resolution output from a linotron or similar), otherwise you got a piece of letterhead and ended up recreating the logo yourself in Illustrator.

Then, when you handed the work back with a copy of their logo in illustrator format, they'd wonder WTF they needed the disk for…
Click to expand...

haha, what a nostalgic feeling :)
 
preference |ˈpref(ə)rəns|
noun
1. a greater liking for one alternative over another or others: a preference

Don't ever question me over the use of a word.

Advantages and disadvantages of JPEGs:

Pros:
- high controlled degree of compression. The user independently selects the ratio quality/file size;
- small file size;
- format is compatible and it is displayed correctly in any browsers, text and graphics programs, on all computers, tablets and mobile devices;
- suitable for full-color realistic images with a lot of color and contrast transitions;
- picture quality is high with small degree of compression.

All these features provide tremendous popularity of the format.

I use jpegs because I send my files to many friends and a lot of them have PCs and jpegs make it easy for them to open them. Do you have a problem with the way I do the things that work for me?
 
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