A quick question. What resolution would people recommend if you want to get a decent print out on a 75 x 50 poster? The images in question could probably tolerate a little blurring, but I'd still like them to seem photographic.
P.S. - if you are in the UK, any recommendations on poster printing services?
Thanks!
at least 150dpi. which means for 75cm which is more or less 30 inch you should have at least 4500x3000 pix. Ideally you should have the double, 300dpi, then in your case 9000x6000pix.
Yep, 300dpi would be your best bet. Bes of luck rendering an image at that size. Mind you, I have had some good results using one of the few image resizing apps (the ones that ONLY resize images) Something Lizard springs to mind. Blows up an image 5-600% with very little loss of quality. The software isn't too cheap, but it does 1 thing and it does it really well ;D
Miles
P.S. I'll have a rummage and see If I can't find the name of the software for you
PPS. http://www.imaging-resource.com/SOFT/GF/GF.HTM (http://www.imaging-resource.com/SOFT/GF/GF.HTM) This is the one, though it looks like its not for sale by them anymore. If I come across any mor infor I'll let you know
Miles,
Isn't this it? - http://www.ononesoftware.com/detail.php?prodLine_id=2
I've done some 4096x3072 renders and printed them at 50x68, and they look really good! Not at all like enlarged or something, so you could probably print that same render size a bit bigger...
Thanks for all your replies. I don't think I've enough money in the budget for a dedicated resizing program, having blown it on TG2 Deep ;)
I can probably stretch to 4800 x 3600 on the machine I have available, although that will involve doing three crops, as I don't have round-the-clock access. Somebody mentioned the possibility in another thread that this could lead to mismatches in GI, but I can't see why that would happen if the scene stays the same. Any thoughts?
Also, came across this company http://www.intelligence-direct.com/home/index.php (http://www.intelligence-direct.com/home/index.php), which seems a reasonable option for UK people.
Calico
Thats the bugger. I couldn't for the life of me remember who had bought the software! For anyone interested, I'd recommend this whole heartedly. It works really well and gives superb results.
Miles
A few thoughts ...
For the absolute, no holds barred in final output quality, rendering right to the required resolution is definitely best.
But, digital files have an amazing ability to be uprezzed to high quality large format prints. I've printed a 4MP ISO 800 digital still on outdoor vinyl at 5x7' feet and had people amazed that they could possibly come from a camera of that resolution. They were viewing the image from about 10 feet away.
Now I'm printing 10MP ISO 3200 and 6400 images in house at roughly 4x6 feet and they look better still - printed on an HP z3100 on some nice semi gloss paper stock.
The fact of the matter is that your viewing distance is a major factor in determining what resolution you will need in your final output.
If you are talking nose-to-the-print inspection of every detail then you will need the highest resolution possible. In photography, that's either really large format negatives and scanning or possibly photo mosaic of multiple digital shots to get extreme resolution. If you are talking looking at these images from a distance at which you will be able to take in the entire image at one time, then the required resolution drops dramatically (for example, billboards are generally a very low print resolution, but they can look really good when you are driving by on the highway, 50 or 100' away).
I've yet to see any digitally generated content that could live up to that sort of in your face resolution and scrutiny on a large scale - the level of detail needed in the image is incredible and usually falls apart on digitally generated content - mostly because of the time needed to create the detail by the artist.
You really won't need 9000x6000 sized files to produce some stunning output. That's 54MP ... Those 4000x3000 renders you did are approximately 12MP and - if the files are treated nicely - could produce some really great output up to some very large sizes.
One of the great things about Terragen (or any fully digitally generated output) is that you don't have to worry about digital signal noise, lens defects like chromatic abberation, lens flare, diffraction, etc., etc. like you have to in real photography. The output is extremely clean and can be upsampled beautifully.
So, don't think you HAVE to be able to render 9000x6000 to print those prints. And you don't have to have special software for the uprezzing. Bicubic interpolation works great on most images. That's available in most image editing packages out there.
Regards,
Micheal
Thanks mhall. This is helpful. I like the idea of trying what Miles suggested...so I did a hunt and found about three different demos. ;D
Thanks for that very comprehensive answer Micheal - it's good to have input from a professional photographer (and nice site and some v nice photos by the way - my only small, font nerd reservation is Eras Medium for the titling, as it tends to look a bit broken at those sizes :-\) I was thinking about increasing the size in Photoshop anyway, and the image really wants to be seen from about 3 feet away as it's a sweeping vista, so it sounds like 4800 x 3600 will be plenty.
One thing though, how does image resolution (1680x1050 for example) equate to the quality they ask for (150dpi)?
I think the rough and ready answer is to equate pixels per inch (ppi) with dots per inch (dpi). So say you want a 30" by 20" image at 150 dpi. Well, that equates to a (30x150=)4500 x (20x150=)3000 pixel image. For 300 dpi, double it to 9000 x 6000 - that's what mt_sabao was suggesting. But mhall is basically saying that you probably don't need 300 dpi, especially if, as in my case, the image wants to be viewed from a distance anyway.
OK I tried it at 9000x6000 because I'm pretty sure it crashes whenever I go over 7000x4667, it did indeed crash even though it was only using 1.7GB out of 8 but I found that switching on preallocate subdiv cache allows larger renders. So if you've been put off doing very large renders, as I have, by crashes then that's a way to get them done.
One possible method of seeing what resolution you need to get the quality you are after is to render cropped versions at different resolutions and then have them printed at a local lab or an online photofinisher. Send them 8x10 crops of the finished output and different resolutions and have them print them for you. Then view them from the relative distance you expect to view your posters.
That should give you some idea of what you will really need resolution-wise to get the quality you want. It will also let you see how the fine detail in your image is holding up and if you need to work on adding more or not. It may be time consuming to do this the first time, but the results will inform your later decisions about what size to render at and thus how long to tie up your machine on a particular project.
@calico - Glad I could contribute. I've been lurking for quite some time now and enjoying the images and insights to the software without being able to contribute much at all.
@domlib - thanks! I'll look into the use of the Eras Medium ... now that you've brought it to my attention, it's bugging me a bit as well. :) I want a decent sans-serif font for the titles, but definitely don't want Arial. Good, old school Helvetica may work, but something with a decent stroke weight would be nice for the titles.
75 x 50 - is that centimeters or inches? ;D At larger sizes (above about 16x22 inches) you definitely don't need above 150DPI, and in fact most printers won't even print higher than that when printing to large size media.
- Oshyan
@oshyan centimetres. Yes, it makes sense they wouldn't print above 150 dpi above that size.
@mhall thanks again. On the font front, why not try Verdana, which is optimised for web display anyway? Tahoma or Trebuchet are other options.
Quote from: PG on March 03, 2009, 06:09:44 PM
OK I tried it at 9000x6000 because I'm pretty sure it crashes whenever I go over 7000x4667, it did indeed crash even though it was only using 1.7GB out of 8....
Maybe this will improve greatly when we get a 64bit version of Terragen 2, hopefully by the end of the year.
Quote from: reck on March 04, 2009, 07:21:04 AM
Maybe this will improve greatly when we get a 64bit version of Terragen 2, hopefully by the end of the year.
Yeah I hope so, it seems weird that it crashes because of the larger size when the consumed memory is so low though. Maybe it preempts how much memory it will use based on the number of subdiv buckets x how much, on average, one bucket will cost.
Alas, my plans to create a poster size image seem to be foundering on GI problems. Because of time constraints, I can only create this image in crops. Here are two crop slices combined in one image. Originally EXR at 4800 x 3600, then imported into Photoshop. GI Blur radius set at 800, as suggested in previous threads. I guess the problem can be postworked out (how exactly??), but I was rather hoping that TG2 would be able to cope with this. Any suggestions? Should I increase GI Blur even further, or is that a losing battle?
Incidentally, switching GI off, which is the obvious solution, is not an option.
GI blur radius only really effects animations so increasing it will not likely have much of an impact in this situation. The only thing that you can really do to try and alleviate the problem is to use enough of a crop overlap that you are getting GI samples from both sides calculated in the image.
Thanks for the suggestion, and I may try it. The reason that I thought GI Blur radius worked here is that it was spoken of in this connection in another thread http://forums.planetside.co.uk/index.php?topic=5271.0 (http://forums.planetside.co.uk/index.php?topic=5271.0), and when I tried it out on crops of a smaller render (800 x 600), it appeared to work, which is why I'm still mulling the possibility of increasing it further.
Is soft shadows turned on in the sunlight node? Might be worth reversing that option.
Yes it is. I'll see what difference that makes to the render. Thanks for the idea.
EDIT
Unfortunately, removing soft shadows makes too much difference to the clouds (yes, there are some in the next slice) :( Oh well, have to try something else....
GI blur radius does effect stills, but at the levels you have it at I don't think increasing it further is going to help. Increasing GI sample quality (and not necessarily GI relative detail) might help though. For example you might try GI relative detail of 1, sample quality 3 or 4, and blur radius 300-500. I'm not sure that would resolve it, but it's worth testing. If you were to go with a non-GI approach you would actually build a fill light rig to emulate your current lighting results. It probably wouldn't be too hard actually, judging by the image you've provided so far. The hardest area to fake GI lighting is clouds and I don't see any in your current scene so far.
- Oshyan
In fact, there are clouds in the next crop (which hasn't been done yet), and the lighting in them is quite important, so I'm afraid GI is important. I'll try the GI detail/sample quality change. Thanks!
Oshyan, I tried your suggestion re lowering relative detail and upping sample quality. Sadly, no dice, as you can see below - even after slightly adjusting the exposure of the second slice. I guess this image is just stressing the GI model too much, and I'll have to laboriously postwork the joins out as far as I can (any suggestions on the best way to do that in Photoshop?). I may have a shot at Rarcher's suggestion too, and also try cropping differently.
What effect does soft shadows have on the clouds? If it fixes the problem then we may be able to work out a solution so you can keep the effect your looking for in the clouds.
I can assure you that having a large enough crop overlap will both minimize the problem as well as make it much easier to properly composite the image together afterward. For a rough guide as to how much to overcrop, Moodflow posted some general guidelines a couple years ago:
http://forums.planetside.co.uk/index.php?topic=2261.0 (http://forums.planetside.co.uk/index.php?topic=2261.0)
@PG - it's kind of difficult to describe what effect it has, except to say it makes the clouds look less complex, and since I want to make them look complex, that's not so good. The other thing is that the current lighting in the scene is the result of extensive testing already, and I'm very happy with it, so I would rather avoid having to re-invent it. I think I'm going to try RArcher's suggestion first.
@RArcher - thanks for the link to Moodflow's post - this looks like the way to go for now. I just wanted to see if Oshyan's suggestion could work some unexpected magic.
It's interesting that this scene challenges the GI so much. It doesn't seem that complex, but then again it does have a lot of very bright surfaces that may be contributing. I agree with RArcher, having a good level of overlap in your crops will help. Photoshop also has a built-in stitching system that works pretty decently...
- Oshyan
Alas, even using overlapping tiles, inconsistencies are still appearing - see the attached file, which combines a 34 percent crop and a 21 per cent crop (I had to reduce the size of the crop because 34 percent was taking too long - about 8 hours, which is the longest I can sequentially use this machine :() The line in the clouds is obvious. Maybe this file is so stressful because of the bright surfaces as Oshyan said (the snow has a reflective shader) and also a lot of light in the clouds - high scattering colour, 0.9 Enviro light, Ambient on. Maybe Planetside could use it as a test file?
I guess if I want to get this file done in one go, I'm probably going to have to consider a render farm. Has anyone had any experience with this company? http://deadline.emecstudios.be (http://deadline.emecstudios.be) It looks my likeliest choice, unless the RenderFarm.ca site featured in this thread http://forums.planetside.co.uk/index.php?topic=5870.0 (http://forums.planetside.co.uk/index.php?topic=5870.0) comes back online.
That is unless there's a kind soul out there with a big machine and some time to spare... any takers? :-\
Maybe you should just use the software to create the higher resolution images?
I don't quite follow you calico - that's precisely what I have been trying to do, but as the thread should make clear, I don't have access to a sufficiently powerful machine for sufficiently long. And cropping and stitching isn't working because of the scene's lighting - which I want to retain. So my only current option - since I don't have the money to buy a new machine - is to go to a renderfarm. Unless, as I said, someone has spare capacity on their box.
When crop rendering + stitching don't you need to overlap the renders a slight bit to get proper lighting due to GI and such?
also if you want I don't mind giving it 3 of my 4 cores on my desktop for a while to render.
Yes neuspadrin, I understand the part about rendering overlaps - the example above has a 10% overlap, but it still didn't work :(.
Thanks for offering 3 of your 4 cores. Just to be clear on the request - we're talking about a 4800 x 3600 pixel render that I estimate would take somewhere around 25 hours using both cores of a Pentium dual E2180 @ 2Ghz. If you still think it's doable, then email me and we can sort out file transfer. Thanks!
yeh thats np, i've left renders for days previously on the computer back when there wasn't multithreading, and I've done overnight renders a lot recently, I generally turn it off at night but its not like i need to.
I'll pm my email.
I've started render, just double check all the settings on the file you sent just to make sure they are what you want, if you want any changes I can just restart it. Only change I did once picking the renderer is to uncheck crop. If you want you can bump up quality a little probably.
There's about three major programs on the market that you can demo that do not require the cropping and stitching and supposedly (notice I haven't tried these) can expand an image quite large without very much deficiency in the end result. Are these listed here? I didn't check.
Quote from: domdib on March 18, 2009, 06:18:03 PM
I don't quite follow you calico - that's precisely what I have been trying to do, but as the thread should make clear, I don't have access to a sufficiently powerful machine for sufficiently long. And cropping and stitching isn't working because of the scene's lighting - which I want to retain. So my only current option - since I don't have the money to buy a new machine - is to go to a renderfarm. Unless, as I said, someone has spare capacity on their box.
It's true that these re-sizing progs exist, but the fact is that they will never do as good a job as simply scaling the image in TG2 - particularly, I would imagine, with clouds, which play a major part in this scene. I just downloaded one (Enlarger Pro) and tried it, and frankly, wasn't impressed. And Genuine Fractals doesn't even work with my version of Photoshop. Fortunately, neuspadrin is lending me his machine for a while, so the problem is hopefully solved. :)
Currently looks like the render will be done this afternoon/tonight.
Thanks - would be interested in how long it takes exactly, and what your exact setup is.
The important stats for TG2:
2.4ghz core 2 quad (http://www.newegg.com/Product/Product.aspx?Item=N82E16819115017)
4 gb of ram (http://www.newegg.com/Product/Product.aspx?Item=N82E16820231122)
Running in 64bit Windows Vista Ultimate.
Probably would've been done by now or much closer had I used all 4 cores. The computer I'm using cost $1700 to make in oct. 2007 buying parts off newegg.
Currently at school, but I'm done with classes at 1:30 or so and render should be done/near done.
------------------------------
Yep it was done when I got back home. 16 hours using 3 cores. Check your email dom. 46 mb exr file ;)
Thanks to neuspadrin, I finally got the image done. And what's more, it even re-sizes up quite gracefully in PS6 to twice its size. Thanks for everyone's help and advice.