HDRI backgrounds are extremely low rez

Coryllon

I understand I am JUST using these images to create something outside a window or behind a forest full of trees, but these are extremely out of focus and I don't want to DOF on every image so looks better. I don't know anything about HDRI backgrounds but my impression is that these should be 4K ish... All I am doing is double clicking them on Render Setttings, so I assume I am missing a major configurations step.

fixmypcmike

Some HDRI's are only intended to produce lighting and reflections, and not to be used as backgrounds also.

NorthOf45

HDRI images are not necessarily high resolution images, they are high dynamic range images. For example, the default HDRI for the Iray render engine in Studio is only 512x256. The full-sized high-res version (8K x 4K) is included with Studio in "DAZ Studio Iray HDR Outdoor Environments" and is suitable for background images as well as lighting. Some are 16K, some even 32K, but they really slow things down. Some might have built-in DoF. There are many "light probe" HDRI's that are intended only for lighting, so check which type you are using.

I noticed that the included HDRI package has two sets of images, one for lighting only and one for backgrounds. Had me scratching my head for a moment...

Hylas

It depends on the size of the HDRI. If you want to use an HDRI as a visible background without DOF it should be at the very least around 20MB and that's on the low side. 100MB is better.

I once downloaded one that was about 350MB and it promptly crashed DAZ Studio. Maybe don't do that, either

Lissa_xyz

Try the ones from HDRI Haven. All cc0 license and none I've seen so far are blurred.
HDRIs: All | HDRI Haven

Coryllon

The one I am using is this: https://www.daz3d.com/skies-of-gaia--20-8k-hdri-skies-with-pre-rendered-terrain-for-iray

NorthOf45

Those should be very clear. What do you see if you just load one of them by itself and render or preview in Iray?

Coryllon

I will let you know once I have finished my render I am working on

Sevrin

8k isn't crazy high resolution.  Keep in mind that HDRIs are not meant primarily as a substitute for geometry.  Sometimes they're good enough, but they're not intended to be the focus of the render.

This is one of Cake and Bob's HDRIs.  One's 8k like the Skies of Gaia, and one is 16k.

Even the 16k doesn't look as good for creating a realistic forest background as what you'd get using something like UltraScenery.  Fortunately, we have access to geometry.

Coryllon

I just need something to fill a window with or place behind a set of trees so there is not a blank spot in the scene

onix

If you only need the background image and not the illumination, you can just upscale any HDRI using some AI upscaler

Although I wonder how it can be that you are unsatisfied with the resolution of 8K image.

 

Coryllon

The max resolutikn on one of my shaders in my image is 3K. So the entire image is as well. The resolution of That part of the image looks more like 200. Not exaggerating. It is blatantly obvious when you know to look. It look like someone took CGI camo turned it into vinyl decal and stuck it on the window. I stopped the render early but you'll get the idea: https://www.deviantart.com/gamopsdirector/art/Not-That-Jaesa-863371528?ga_submit_new=10:1607337842&ga_type=edit&ga_changes=1 Take a look outside the window on the left behind the statue.

Richard Haseltine

3,000 pixels wrapped around a sphere is about 8 pixels per degree - not many at all.

Coryllon

So I need to do what? I am sorry HDRI's are not something I am familiar with. If I understand what you are saying is if I want a higher resolution background, I would have to lower the resolution of on the entire image. That doesn't make sense to me. The HDRI is the same size image regardless of how many pixelsnj am using if I make an image at 2K resolution the information for the image shouldn't change. Is still 8K it's just using 1/4 of the information. So if th answer is then I need to "shrink the dome size how do I do that? Additionally, I'd it's getting 8 pixels per degree then there is no amount I can shrink the dome to that will allow me to put a full sized person in, let alone a scene. The logic doesn't track. K assume I am wrong about something but I have no idea what. Also this is not a 3000 pixel sphere this is a 3000 pixel render. Just the 2D plane I am "snapshotting"

Richard Haseltine

I wasn't suer what you were saying was 3K. Whatever size the HDRI is, divide its width by 360 to get the number of pixels available for each degree - how many degrees the view you are rendering subtends will depend on your camera's focal length (and other settings that are less often varied). Because a lot of the HDRI is out of sight you need a high resolution to give sharp results, especially with a narrow field of view (high focal length).

Coryllon

But isn't it always going to be a 360 degree image anyway, regardless of focal length,it seems like even 16K then won't be enough and and 8K would never work and always be low res regardless?

Richard Haseltine

Coryllon said:

But isn't it always going to be a 360 degree image anyway, regardless of focal length,it seems like even 16K then won't be enough and and 8K would never work and always be low res regardless?

Yes, this is a regular problem. Focal Length affects how mush of the 360 is visible in the eectangular image - the more zoomed in you are, the smaller the segment.

Coryllon

So how does one resole this issue? For what it's worth, I changed it to a 16K HDRI.

dawnblade

Coryllon said:

The one I am using is this: https://www.daz3d.com/skies-of-gaia--20-8k-hdri-skies-with-pre-rendered-terrain-for-iray

You should probably stay clear from V2 then because a number of us couldn't get them to render as crisp as the promos. 

NorthOf45

If you want high resolution background with a forested view, maybe Skies of Gaia isn't the right starting point. They are all the same long shot of mountains, with a some greenery scattered on the slopes. Skies of Sylva uses shots in a forest from the mddle of a dirt path, so the trees are maybe 50 feet away. There are also products purely made for backgrounds, not the sharpest images, but they do fill a niche. Or, render your own background from a forest scene and use it as a backdrop or background billboard.

Sevrin

Coryllon said:

The max resolutikn on one of my shaders in my image is 3K. So the entire image is as well. The resolution of That part of the image looks more like 200. Not exaggerating. It is blatantly obvious when you know to look. It look like someone took CGI camo turned it into vinyl decal and stuck it on the window. I stopped the render early but you'll get the idea: https://www.deviantart.com/gamopsdirector/art/Not-That-Jaesa-863371528?ga_submit_new=10:1607337842&ga_type=edit&ga_changes=1 Take a look outside the window on the left behind the statue.

The patch of green from the HDRI sticks out like a sore thumb in the image, and that's why you notice it more, and why the blurriness becomes a problem.  The viewer's attention is also drawn away from the main character because of that.  You'd be better off with a background that blends in better with the other colours in the scene.  Also, I would use depth of field, so that far wall is about as blurry as the HDRI, and that will help your character stand out, as well.

kenshaw011267

8k should be enough for a background out a window unless it's going to be a major part of the image, I use 8k HDRI's as backgrounds quite a lot and they are almost always good enough, but I source from hdrihaven and they have very high standards for the images used.

 

Coryllon

So if I use a 16K  still get the same crappy resolution, I can't beleive no resolution from the daz store is good enough to use. When using an HDRI I HAVE to assume there something you do besides double click on the render/backdrop and hit "Render".

Sephiroth

I am having the same issue using the: https://www.daz3d.com/neural-notions--quantum-landscape-8k-hdris HDRI's. These are GORGEOUS in the promos, but I cannot for the life of me recreate the effects that I paid money for.... Any suggestion to getting the HDRI's to look like they do in the Promo would be fantastic. I have tried pasting the HDRI image on an imported rectangle to no avail, and was able to get a floor to act reflective but without the wavy effect. Nothing in the surfaces tab suggests being able to make a wavy reflectioon either. 

I know for a fact I am having the same issue as the OP.

Sephiroth

Coryllon said:

I understand I am JUST using these images to create something outside a window or behind a forest full of trees, but these are extremely out of focus and I don't want to DOF on every image so looks better. I don't know anything about HDRI backgrounds but my impression is that these should be 4K ish... All I am doing is double clicking them on Render Setttings, so I assume I am missing a major configurations step.

BUDDY!!!!! I figured it out if you havent already 3 years later haha. In your render settings tab, go to Environment. Look for a setting that says: Dome Scale Multiplier. DECREASE it to 10 or below. Porblem. SOLVED!!!!!