Continued issues with lighting - skydomes
Hello All,
I know I just recently posted issues I been having with interior lighting and for the most part I am fine with exterior lighting using the stock skydome with Daz. I know how to dhange the angle and pitch (time of day), etc. So using that is fine. However, the issue I have an issue when using a skydome from a package such as Iray Worlds - Skydome and also this Oak Tree package I just bought:
https://www.daz3d.com/iray-worlds-skydome
(This too):
https://www.daz3d.com/easy-environments-winter-ii
And
https://www.daz3d.com/merlin-s-oak-plants-and-props-set
The problem I am having here is that both of these packages create a 'smaller' skydome within the stock Daz Studio one and they have their own lighting. Used as is, I don't have a problem, but if I put in a prop and the light is being blocked in some way, the issue comes in wanting to move the 'sun' light. I found out very quickly that because this is a dome within the main dome of Daz, that the Daz Enviroment controls no longer work since it is controlling the original skydome and the new skydome inside it, is blocking it. Just yesterday I found out that hidden within my Content Library, I came across a bunch of green circular icons with a bright yellow dot on it. One of them was labeled 'sun'. So breathing a sigh of relief that I CAN adjust the sun within a package Skydome, my excitement quicky turned to disappointment when I found out that instead of moving the sun, it moves the entire scene instead. So with one scene I was working with, in which I had a building over water, when I clicked on one angle, all of a sudden the building was halfway under water! So naturally it has me thinking why would it be designed like this?
With the Merlin's Oak Tree, the issue I am having with that is that it uses a distant light for the sun, but it is OUTSIDE the (package') skydome and inside it is VERY dark. So this had me doing a WTF as why would someone put the light OUTSIDE of an opaque dome? So it has me wondering if there is a way to make the dome translucent or semi-transparent to let the light through?
Again, I am new to Daz and still have much learning to do. But it does seem that some of these products are a bit counter intuitive as they do not come with any kind of instructions and in the case of the Oak Tree, it doesn't even work! I can easily see that I am missing some kind of setting with the Oak Tree, perhaps a translucency or opacity setting? However, I do not like the sun controls on the Iray Skydome package at all in that it disturbs the ground settings. What I would like to know is if there is a way to allow the light from the stock Daz skydome to enter the Skydomes and thus I can resume control of the light (sun) using the Environment controls in Daz? Alternatively, is there a way to change the Daz Skydome itself to something like a sky with clouds setting like the Skydomes have in Iray Worlds and the Winter II environments? I know the stock skydome is a low resolution of a picture. So that has me thinking that can be replaced.
Finally given the wonky control system of Iray Worlds: Skydome, I would be looking for something better, either through an alternative above, or a better package. I do know of Terradome 3, but heard it is very taxing on rendering. Even though I do have a fast machine, I don't have a GPU as of yet and am using only the processor. So whatever I do has to be light on system resources.
Any information on these packages or Skydomes in general would be of great help.
Thank you.
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Good morning, @jukingeo. (It's morning here, anyway.)
I don't have the Easy Environments product, but I see from the "What's Included and Features" on the product page that it supports both Iray and 3Delight (3DL) in Daz Studio. Based on owning several of Flipmode's Iray lighting products, I'm going to guess that you have loaded a 3DL skydome into the scene. For Iray, you want to load the HDRI instead of the skydome. There should be three "Render-Setting" presets for that: FMEE WinterII Scene Iray HQT, FMEE WinterII Scene Iray, and FMEE WinterII Sky Iray.
I've found the easiest way to locate a preset when I know what product it is, but can't find the preset elsewhere, is to go to Smart Content, select the Products tab, type the name into the filter field, and then click on Default in the left column. Then I open the product and locate the preset. (A good way to become familiar with the Content Library is to right click on a preset in Smart Content and select Show in Mapped Folder. A lot of older products don't have the metadata to show up in Smart Content, so learning the Content Library is important.)
I don't have Merlin's Oak, but I can tell you it is is an older product developed long before Iray was added to Daz Studio and the skydome will not work in Iray as loaded. There are ways to use the older skydomes, however, by making changes to the material settings. I'll post a link or two about it shortly. I'll have to look those up.
I do have Iray Worlds SkyDome, so I can test that for you. I'll load the Iray Worlds SkyDome and see if I can give you some specific answers.
As for TerraDome 3 (TD3) using the entire product can be taxing on your system, that's true. However, you don't have to load the props to use the TD3 HDRIs. I use them all the time without the rest of the product. The biggest limitation to these HDRIs, in my opinion, is the lower half of the images are flat ground, and you'll need to make sure the "horizon" is camouflaged if the ground doesn't match your scene.
Talk to you in a bit. I'm off to play with Iray Worlds SkyDome…
An assorment of ways to use 3DL Skydomes in Iray:
One big issue with using the older skydomes instead of an HDRI is the bottom of the dome will be where Iray determines the ground to be unless you set Ground Position Mode to Manual. But when you set the mode to Manual, Iray will cut off the dome at the floor position, (where the grid shows when you have Show Floor enabled from the Viewport menu.) As long as you are using a set with a ground prop, you should be okay.
A quick test using a set with ground and skydome modified as show in the last link did not create any shadows on the ground prop. I loaded the horse, and even set the luminance very high, (1500 Kcd/m^2,) and while it made everything too light, there still wasn't a shadow. I was using the Sunset materials for Lakeside Folly. skydome.
I've loaded the Iray Worlds Skydome prop into a new scene. It consists of three objects: The skydome, which is a half sphere; the ground; and the sun. The dome and sun are parented to the ground. If you have the ground selected and click on one of the sun position presets, the ground, and everything parented to it, is moved. If you select just the sun and apply a sun position preset, just the sun is moved within the dome.
Based on this very quick test, I suspect you had the ground selected when attempting to position the sun.
However, in my Content Library, the icons for moving the sun show a bright white "dot" over a circular green field. They are located in the Content Libray under [LibraryName]->Environments->Iray Worlds->Iray SkyDome->3 Sun Positions. Is this where you found the presets? If not, the ones you used may be for another product, and may not give you correct results even with the sun object selected.
Hello L'Adair,
I will get to all of your messages, but for now I can say this is as far as I got with the Iray Worlds sun postioning as well. I also just found those sun presets this weekend and after over an hour of fiddling with them, (setting one, wait to render, set another, wait to render, etc), I just found it very counter-intuitive to 'guess' which was the right one. Then I had the strange results with my scene going under water and probably you were right, I had the ground set. What I was looking for was something similar in operation to the Daz stock skydome in which I have those nice controls in which I can set the time of day for the pitch and then rotate the whole dome around. So for me the easiest thing would be to have some kind of dome and sun that replaces the stock one, so I can use those controls. In the meantime I did find a trick I can do with the Iray World's domes that mimics the effect of rotating the stock skydome with a dial control. As it turns out, the main reason why up to now the Iray Worlds Skydomes worked for me was that I rotated my figure into the light. And this worked for small backdrops and such. But now I am doing bigger stuff and starting to build scenes and it is pretty hard to rotate all of that. So I looked at my right panel wher the scene items are and the skydome dome is s selectable item. This both know. Since I used the Y axis to rotate my figure and sometimes an entire scene, what if the converse was true. Why not rotate the entire dome using the y-axis control? So I tried it....It works! The only problem is the pitch. That I would have still set using a sun preset as before and sadly it is only three height levels. While this does work, I would like to have the control over the sky dome like I do with the Daz stock skydome.
Also to quickly answer the Merlin's Tree dilema. When I was reading about the trick to lop off the top of the 3DL skydome to create a cyclorama, it dawned on me that the Merlin tree package comes with a cyclorama already. They probably included it to avoid that horizon problem that you mentioned. So really the sky dome is only needed for the sky image. So I could remove the dome altogether and use the stock dome. However, because that is a huge tree, it blocks out the light and that creates another issue of which I experienced with a tree house package I bought. (Please see attached)
Now I am pretty much dealing with a situation as I would with trying to light an indoor environment and as you see from that render, I having trouble in that area too. This is using not using the skydome that came with the tree house and setting three lights. Whatever is leaking in from the stock skydome. I added TWO lights which are on the front character and she looks poorly lit along with the surrounding area. The character in the back only has one light on her and it is set around the same lumens and she is nicely lit. So I don't get that. There are so many unwanted shadows around too! Such is the problems with putting things in or under a larger tree.
Question. For these older domes, is it possible to create a sun using a regular light control so this way I could see thorugh it like I could a regular light through the camera drop down panel? Is there a way to keep the dome, but nix the original sun to do this? Or should I enter the wonderful world of using ghost lights?
Thank you for being diligent and looking this stuff up for me. So I think the main thing I need is to have a skydome in which I can use the controls for the stock dome on and in addtion, having a bright light, like a sun that I could control like a regular light and be able to see through it and postion it that way.
Thanks!
Geo
Hi, Geo.
First, I want to verify the "Daz stock skydome" you mentioned is the default Environment in Render Settings. Correct?
The Environment has a lot of settings, not just the Environment Map, ("dome") and your copy of DS includes the DAZ Studio Iray HDR Outdoor Environments, with five high resolution environments, (including a high resolution, ie not blurry, version of the default HDRI.) These HDRIs are suitable for backgrounds when you set Draw Dome to On.
When you load the Iray Worlds prop, it sets the Environment Mode to Sun-Sky Only, but with the Environment Intensity set to 0.00 so it has no effect on the scene..You can set the Environment Mode to Scene Only and still get the same results. Both the skydome and the sun prop are emissive. They provide all the light in the scene, unless you add lights. The sun in Iray Worlds is an object. You don't actually need the presets to move it around. You can select it and move it to where you need it. Although I suspect the whole thing is optimized for the sun being a bit high in the sky, and you'd want the light of the sun to be coming from the same general direction as the main "light" in the skydome image.
I think your solution to select the Iray Worlds and rotate on the Y-axis is best when using this set.
However, for future reference, you can also use a group to move things in the scene. If you create an empty group, the X and Y axis will be centered at World Center. If you select items and then create the group, the X and Y axis will be at the center of those items. This can be handy for more than just rotating the scene.
You won't be able to rotate the Iray Worlds skydome on the X or Z axis because it is only a half dome. Not like you would the HDRI in the Environment settings. You can try selecting the skydome and rotating either or both, but there will be a gap. This might not be a problem as long as the gap is behind your camera. But there won't be any light coming from the gap without futher Environment changes.
About your treehouse render, or any render with obstructed light, you need to "enter the wonderful world of ghost lights."
Think of the real world. In the middle of the day, even with curtains closed, light still makes it into your house, (apartment, flat, room, etc.) Even if the light is low, your eyes compensate with the pupils opening more, making the light sufficient to see by. Open the curtains, and more light comes in, and your pupils open less to let less light in. Unless the sun is shining directly into the window, the light coming in through the window doesn't create deep, distinct shadows, (like the shadows on the wings and behind the foreground character in the image you attached.) I use ghost lights a lot specifically because the add "ambient light" without adding any shadows to the scene.
The Iray Ghost Light products from Kindred Arts make using ghost lights really easy. But before KA created the products, he shared how to create our own in a forum thread here. Because these lights are all but transparent, they don't cast shadows, nor do they cause spectral light on objects in the scene. And you can put them just about anywhere in your scene. It's really a rare image that I don't use ghost lights.
To use an old skydome with Iray, imo, you need to treat it the same way as the PA has the skydomes in Iray Worlds. Put the image in the Emissive Color channel and set the color to white. Set the Emissive Temperature to 0, so the color stays true to the image. Set Luminance Units to Kcd/m^2 and Luminance to a high value. (Remember, a value of 100 with Kcd/m^2 selected is actually 100,000.) Test the results using Nvidia Iray in the viewport and increase or decrease Luminance to achieve the level of light you need.
It may also be possible to use light outside of the dome. You'll need to make the dome transparent, but leave the Cutout Opacity at 1. To do that, set Refraction Weight to 1. This will make the mesh act like a window, instead of a wall.
This is an image I rendered after converting the Via Serena to Iray. I was attempting to recreate one of the promo images. The sky is the included Skydome, using the same, or similar technique described above. I'm also using the Iray Sun Dial. (You can find the full size image on the gallery page here.)
If you look through my galleries, you will see a lot of outdoor images that use only an HDRI to light the scene. (Other lights for highlights, but not the overall scene.) I have a lot of HDRIs. lol
You're welcome.
Hello L'Adair,
BTW, do you have any connection to this:
https://www.daz3d.com/ly-adair-hd-for-genesis-3-female
Yes, I am referring to the default environment when I say 'Stock' or 'Daz Skydome'. You are saying there are five environments? How do I change them out?
I have noticed that when I have an Iray Worlds Skydome in place that the Enviroment controls do not work. Like I said, I recently found out how to move the Skydome. I don't recall selecting the ground. But I might have selected the dome along with the sun and perhaps that caused the water level issue.
Yes, I like using the Y-axis control to rotate the dome / sun. Not only can I position the sun, but I can change the horizon too that way. The only problem is the pitch (time of day) as I don't have as fine a control as I would with the default environment dome.
How do you do this grouping thing now?
I know that the Iray Worlds Skydome is only half a sphere, but it has the ground too and it seems to match up fine, but yes, it does seem that rotating it with the sun selected instead of the sun alone will create some problems.
I have been looking at some tutorials already and from what I seen on You Tube, it does look like these ghost lights can be created without buying a package. That tutorial you linked to is much like those tutorials.
Kindered Arts does have one on the light kit too:
It would seem like if I put a sphere shaped ghost light in between my characters and a plane one in the front behind my camera, that should do it. I have to play with that.
So here you are making the skydome an emissive surface? That would be a cool way to fix my Merlin Tree problem. It does seem like an HDRI might be more what I am after, but I would want one that looks more like a sky and would I then have control over it using the Environment controls for the default skydome?
So really I would like something that looks like a sky and naturally has a bright sun. Also I do a lot of 'portrait' type work and many times I do not want to set up an elaborate set as that does increase render times. So I would love to have a simple backgrounds like this:
https://www.daz3d.com/cyclorama-portrait-paper-backdrops
A cyclorama. Traditionally, photographers use a photographic background roll like this:
https://www.daz3d.com/z-photo-studio-environment-with-poses-for-genesis-3-and-8
Now between you and I (and those reading) there is NO way I am spending that amount of money for lights and a backdrop that is glorified to look like a photographic studio. But I found an issue with those rolls. Shadows on the backdrop...
However, that first item I am interested in. A cyclorama is usually so large that shadows are not a problem. Better yet, would be if there is a skydome that had that cyclorama look on one side and a light source on the otherside AND I can control it with the environment controls to position the light where I need it. Is there something like that?
Thanks for help and time (as you invested quite a bit of it here with your multiple responses. I appreciate that).
No, I have no connection to Lyoness or any of her products.
To change the HDRI in the Render Settings->Environment, you need to locate the presets. Daz Studio provides more than one way to do just about anything. The following is just what I think would be easiest for you to find at this point.
Each HDRI has two presets. The presets labeled "Background" load only the HDRI. The other presets load both the HDRI and Cameras. The HDRIs load with Draw Dome set to On.
Please open a new, blank scene in DS.
Open the Render Settings pane. This is probably docked to one side or the other, dependent on the layout you are using.
I believe these are the Environment controls you refer to. These settings only control the Iray environment. You cannot rotate an object with these controls. Dome Rotation settings only affect the position of the environment lighting in relation to World Center, (xyz axes of 0, 0, 0.)
It doesn't matter how large the object, to rotate it, you will need to select it in the scene. You probably have a Scene pane (tab) docked to one side of the viewport. You can select items in this tab, as well as in the viewport, but often have better control of what you're selecting in the Scene tab.
I believe you are getting frustrated with the Iray Worlds because you see it as an Environment and it only seems natural it should be controlled by the Environment settings. However, it is an object. It has a mesh. And it is moved with either a tool or settings in the Parameters pane.
To create a Group, go to the Main Menu and click on Create. Scroll down to New Group… and select. A dialog window will open where you can name your new group. The default name is Group # where # is an actual number which increments. Click on Accept. As I mentioned before, you can select items to group first, or you can create the groups and then move items into it. Items in the group are considered children, with the group as the parent.
I'm pretty sure Ghost Lights were Kindred Arts' brainchild. That said, stick with whichever tutorial teaches the way you learn.
One reason why ghost lights work is they use a single poly to light an area. You can actually use any mesh. The difference between "mesh lights" and "ghost lights" is the latter are all but invisible. But… Iray will have to compute the effect of the light on every polygon of the mesh light. The more polygons used, the longer it will take to render the scene. The sphere you are thinking of using between your characters may add more time to the render than you expect. You can use a single poly plane between your characters and turn on Two Sided Light in the material settings, (Surfaces tab)
You don't need to spend money to get a nice backdrop for your renders. You can turn Draw Dome to Off, render the scene, save the render as a PNG image and the background will be transparent. Now you can add any background you want in any image editor that uses layers. I use Photoshop CS6. Gimp is open-source and somewhat like Photoshop, (though I've never spent much time with it.) There are others, I'm sure. You can create simple backgrounds in your image editor, or use one of many free backgrounds available in this Art Studio thread.
You have just described HDRIs. Not all HDRIs are like that. But the HDR product that comes with Daz Studio is. And here are a couple of products in the store that meet that criteria:
There are also websites that have free HDRIs, although I am not familiar with them.
I see from your other lighting question post that the image you were talking about using Ghost Lights with is the same one you shared a few posts back in this thread. Talk about a doh/facepalm moment! How embarassing.
The image looks really good with the Ghost Lights. I see now why you wanted to use a sphere between the two figures. What I said about the polys still applies, though; You could try using a cube instead of a sphere. See if that reduces the render time any further.
Hello L'Adair, I am going to answer this message first since I am in a render right now and cannot try what you suggested in terms of the skydome. Yes, that is the same image as I had a tough time lighting that area. But since I had a related skydome question I also used it here. But the Merlin's Tree example was more relevant as with that one, the tree was a bit more open and I could have used the skydome. But I was just questioning as to why the distant light was outside of the dome.
Thank you. Yes it did come out much better and I really wasn't even trying! I just removed the four lights I had and subsituted the spheres. I made some lumens ajustments and did some test renders. Then I did a full render and timed it. I was surprised to see that the render time went down to less than half! As for using the spheres, I wanted coverage all around, particularly from the ghost light that is in between the fairies. The one that was behind me I could have used a plane though. But I was trying the node trick out in one of the tutorials. There is a cute trick in which you can make a node instance of a primative and thus make an exact copy of the original and keep all the properties. The best part is that if you want to make an adjustment that affects all of the node, you just have to make the adjustment to the first or parent node. I thought this was a good idea in the event I had to just bump up the lumens a notch at a time while I was in Iray mode.
So it was Kindered Arts that came up with the ghost light idea?
I found out that if I make slow increments that the time between renders drops. This makes it VERY convenient to position the sun of a skydome.
To answer some of your questions from the prior post. I don't mind spending some money if it is something I can use. Having those cyclorama skydomes is useful because when using the Environment Controls under the Render tab, that default image is an HDRI if I am not mistaken, right? The issue here is that I cannot see the image when I am in textured mode. But with something that has a backdrop like these:
https://www.daz3d.com/cyclorama-portrait-paper-backdrops
...That will not matter as the background is not dependent on postion. But the sun is relevant and I can use the method I mentioned above...with moving the 'sun' in small increments so I get the faster renders and can see where I am putting the sun.
In terms of HDRI images, I did find this site:
https://hdri-skies.com/
A great majority (if not all of them) are free. They have both low and high resolution versions too. The only thing is that most of them are general scenes and I would like to get more of a cyclorama look for when I do portraits.
I know that many of these HDRI 'domes' seem to be a quick way to just place a figure and just render. But I find the ones that have buildings or rock formations fairly close that it is hard to get my character in position because of the issue that I cannot see the HDRI until it renders. The winter environement I mentioned earlier, I did find the HDRI dome for that and that is a better example to what I am looking for because the position of the dome is not really that relevant. What is more relevant (image wise) is that I can postion the sun. So the Winter environment or other backdrop even with a ground would work. In your examples above, that would be the Four Seasons one. That one seems to have a surrounding backdrop with nothing 'obtrusive' in the middle.( The first link is a perfect example of what I DON'T want). However, even with this type of HDRI dome, there is one caveat...While I can change the sun's rotational position, I can't change the pitch for that would change the horizon of the image. That is why I was saying I would prefer a cyclorama style background for the dome because then I CAN change both the rotational aspect and the pitch of the sun. With my newfound knowledge of ghost lights, I can use them to do highlights with the dome if I want to. As ghost lights don't shut the sun off like the other lights do.
BTW, that was one of the settings you mentioned above, correct? That was something I never liked that as soon as you put a light in the scene, the skydome shuts off. I guess they do it because they figure that someone might be doing an interior render and they need lights in there rather than use the skydome.
I know you mentioned to do a render of the character first and then adding a background, but that is kind of two stepping it. I would rather do it all in one shot unless the render times are significantly different.
Like I was saying, I think what I am mostly after is this kind of effect but with a sun:
https://www.daz3d.com/cyclorama-portrait-paper-backdrops
It would be cool if I could use those images on the stock skydome actually. But they might not be large enough as they are meant to be actual cycloramas.
I looked on that free site and pretty much they only have the HDRI's with a horizon and ground. But that is understandable as the site is hdri-SKIES.com. Some of them are very pretty:
https://hdri-skies.com/shop/hdri-sky-428/
This is good too:
https://hdri-skies.com/shop/hdri-sky-200/
Anyway, I am going to go and play around with some of the Evironment settings and see what happens.
Thanks!
Geo
You're welcome.
I have another question for you. Is there a way to take one of these and make it an HDRI for the Environment Dome?
https://www.daz3d.com/cyclorama-portrait-paper-backdrops
Or are those too low in resolution? I am having a hard time finding a colored pattern like that in HDRI format. Also another issue is that somehow a sun has to be added to it. Something like that would be perfect for my portrait set ups. It is just seems very easy with a one large light setup and all I have to do is postion my character and then use the Environment controls to postion the main light (sun).
However, I do know what is coming next. Once I ace daytime lighting, I am going to want to do dimmer lighting or even some night scenes. But mainly the set up I am looking for above will be the bulk of my work as I do a lot of test renders on new figures I create. Some of those figures will never make it to a full blown set. Many I use all the time.
I like using the Environment dome because it seems to not add much to the render time as opposed to other forms of light.
Given that they have PC+ items on sale now during the latest 'entire lot' sale in the Daz store. I can get those cycloramas for less than $1. (I still would like to find them for free though). Once I have them, I also can experiment with ghost lights too as they also seem to be low on render time. The only thing I miss with using ghost lights is having that on-board camera in which I can see through the light like what you can do with a regular spot light. That would be the ultimate if there was a ghost light with a camera, then I can position it by eye.
No, I'm sorry, those will not plug into the environment image. They will work on the cyclorama, as that's how they were designed. I think you should go ahead and buy the product, test it out and see if it will work for you. And if it doesn't work the way you want it to, you can return it within 30 days. (Daz will refund to the payment source if you specify, otherwise it will go into Store Credit.)
You can add a camera to each of your ghost lights.
You can now view the scene through the Ghost Light camera, as you would a spotlight and moving the camera moves your light.
You can also do this with a horizontal light, but using the Top View of the viewport.
To create a plane for a vertical ghost light, set the Primary Axis to Z-Positive; For a horizontal light, set the Primary Axis to Y-Negative.
I DID buy it last night in fact! Yesterday's (and today's) sale included 50% off on all items if you buy two or more AND it included PC+ items too. So I got the Cyclorma set and those backdrops for less than $2! I still have to check it out to see how it works.
Sweeeeet! I didn't know you can parent something to a camera. Nice trick! That is next on my list of things to try out!
Thanks!
You're welcome. Glad I could help you with something, (not happy about coming up empty on Ellis 8.)
That is OK. I still have yet to play around the Cyclorama pack, but I will. As for Ellis 8, dropping her skin into Skin Builder definitely did something and the skin artifacts are gone. I updated that thread just now. However, I made her skin a bit too dark and much of what made the 'magic' look in her face is gone. She is still pretty though. I am going to go back and try it again but going only a hair darker. Hopefully I can retain the look in her face but get rid of the orange peel look too.
Well, it is official...
I bought these Cyclorama's the other day and I started to use them for the first time this weekend:
https://www.daz3d.com/cyclorama-portrait-paper-backdrops
With that, I did a render time experiment. One using the default Daz Environment Controls HDRI Skydome and one using the Cyclorama. See the attached pictures below:
Both are identical in every way with the exception of the background. The first render was done with the Cyclorama package above. Basically this is your simple photograpy roll as a background. The second render was done with the Environment controls sky dome only. Both renders were done with the Sun / Sky setting and the dome turned 'On'.
Now get ready for this. Using CPU only (I have an i7 6700k Intel Processor with 16gig ram on my machine). The first render took 15 minutes to do, which I didn't think was too bad... However, removing the cyclorama and just using the HDRI dome alone yeilded a render time of about 7 minutes and 35 seconds....nearly HALF the time. So it looks like using HDRI's wins out in terms of render times. As a bonus, unless you are pitched down quite a bit, dealing with shadows is not as a problem with HDRI backgrounds. However, the Cyclormas do play out on the ground for a good ways and you can pull the figure back from the cyclorama and this would reduce shadows there. I just found it a bit shocking that a simply cyclorama actually doubled the render time. Or in better perspective, it added over 7 minutes to it. Still I think that is quite the chunk of time.
So it looks like my Cyclorama idea wasn't the greatest and I am better off using an HDRI, provided it is one like the one that came with Daz Studio. Thankfully I only paid $2 for the Cycloramas. I am going to keep them as they are very pretty and I do like them and more then likely when I get a good video card. The render time for them will go down too. But I don't see them as any easier than selecting a skydome for the Environment Dome. The only other 'pro' to using the Cyclorama is that the background will not change when I change the position of the sun, as with an HDRI the background changes with the sun.
I just was very surprised that there was that much of an increase in the render time for using the Cyclorama.