mixed light conditions - what could be done

[Valentin Arfire]

I would like to learn the following: what can be done to get decent light out of mixed artificial - ie tungsten, flash and natural light at the same time?

if there is tungsten light and a window with some outdoors landscape... either the interior is correct and the window blue, either the window will be correct but the interior turns profoundly yellow.

besides turning to monochrome - let's admit a very nice solution, I found only very time consuming methods.

By now I generate out of raw for each type one image and then photoshop a lot
wish there was a fusing method for all this quite common situations.

regards,

 

[Ben Rubinstein]

Do you have CS4 or LR2? In the local adjusment tools you can paint a WB on a specific part of an image. Works wonders for this kind of thing. Use the paint tool and choose a colour which when added to the image colour will give you the correct rendition. If you need to turn an orange normal then paint over it with blue, etc, etc. The beauty of these tools is that once the mask is made you can go back and change the colours as many times as it takes to get it right.

 

[Michael Fontana]

Valentin

here's what I try usually:

- daylight & flash will work well together
- tungstene doesn't fits with these too.

So there will be 2 RAW conversions from each shot, by whitebalancing for these two sources; let the tungstene a bit on the warm side, there's no need to have it pure white.... looks better and makes the rest easier.

If the final output is a stitch, I found it best to render the two stitches, prior to mix them. You might use enfuse, with priority set to color, to merge it. Sometimes, a bit of finetuning, with a layermask (of one stitch) on top of the enfused stitch is required, to get it well done.

Yep, quite a bit of work, but if you create a template in PTGui, it's faster. I didn't find yet a easier way.

HTH

 

[Asher Kelman]

Do you have CS4 or LR2? In the local adjustment tools you can paint a WB on a specific part of an image. Works wonders for this kind of thing. Use the paint tool and choose a colour which when added to the image colour will give you the correct rendition. If you need to turn an orange normal then paint over it with blue, etc, etc. The beauty of these tools is that once the mask is made you can go back and change the colours as many times as it takes to get it right.

Hi Ben

Can one make the brush from a particular curve obtained by using the WB tool on a gray or white in each section of the image or does one just have to guess the color correction and work more by trial and error.

I have not received my updates yet, so I haven't seen this tool.

Asher

 

[Valentin Arfire]

Hello and thank you all.

here is a panorama (quite a large one) I did some time ago

http://www.photo360.ro/pano/infocentru/infocentru.html

I had to make two of them one exposed for the interior and the other one for the sunlight - especcially since there was also a strong reflexion from the water on the streetway.

Of course there is a conflict between the light in with the quantity of light from outside...
and a two day photoshopping "fun"...

I was hoping there is a program like tufuse that may put together all images and just eliminate the undezirable parts.
Imagine a room with a tungsten that has a curtain in which there are sunshadows and light - how can I keep the curtains color constant while still having a reasonable yellow bulb light inside and enough details?

 

[Michael Fontana]

Valentin

one point you want to adress is dynamic range, the other one WB.
In your VR, you had to work on both.

As for extended dynamic, some helpers like enfuse, sometimes HDR might exists, but they often go for a averaged image, which might be fine in some cases, but not work in all. In huge contrast stitches there's often the need to work a bit manually, as the app doesn't knows your idea about setting the contrast.

As for WB, it's finally a subjective decision, in the RConverter I very often use a different WB than the °tecnical° correct one, to get a certain taste, feel, etc.

But I think you know that all, already. No free lunch...

Maybe there's a shortcut, once you describe your workflow?

 

[Bart_van_der_Wolf]

I was hoping there is a program like tufuse that may put together all images and just eliminate the undezirable parts.

Hi Valentin,

Did you know that in several blending programs you can influence the blending process by first adding an Alpha mask to some of the images?! The final outcome depends on how many images are being blended and how they differ (e.g. in exposure difference, and/or White Balance).

Several programs just use a simple mask (e.g. 0=exclude and >0=include or 255=include, <255=exclude), others allow more delicate masks, where gray mask tones represent partial contribution. So some experimentation with the application at hand is needed.

Cheers,
Bart

 

[Ben Rubinstein]

Hi Ben

Can one make the brush from a particular curve obtained by using the WB tool on a gray or white in each section of the image or does one just have to guess the color correction and work more by trial and error.

I have not received my updates yet, so I haven't seen this tool.

Asher

I'm afraid the latter Asher, it's intended for colouring stuff not correcting WB.

 

[John Sheehy]

I would like to learn the following: what can be done to get decent light out of mixed artificial - ie tungsten, flash and natural light at the same time?

if there is tungsten light and a window with some outdoors landscape... either the interior is correct and the window blue, either the window will be correct but the interior turns profoundly yellow.

besides turning to monochrome - let's admit a very nice solution, I found only very time consuming methods.

By now I generate out of raw for each type one image and then photoshop a lot
wish there was a fusing method for all this quite common situations.

regards,

Any automatic solution would require AI which determines what is illuminated by what light, and would most likely make a lot of mistakes.

 

[David A. Goldfarb]

A few options are available for film photographers, some of which work equally well for digital, some require somewhat different procedures.

One is to gel the tungsten light to daylight. There are also tubes that slip over fluourescent lights to correct them to tungsten or daylight. Yet another option is to gel the windows to tungsten, which is commonly done for movie/television location shoots.

Another is to replace the tungsten bulbs with slaved strobes that screw into a conventional light bulb socket. Here are some examples--

http://www.bhphotovideo.com/c/shop/1388/Slaves_Accessories_Slave_Flashes_Accessories.html

Strobes are approximately the same as daylight, but daylight is a variable thing, so if you really want to match, you use a color temperature meter and gels. When combining strobe and ambient light, you use the aperture to control the strobe exposure (and strobe settings if you have them), and shutter speed to control the ambient exposure, since the flash duration is much shorter than the shutter speed.

Another standard architectural method is multiple exposure. With digital, you do separate exposures and combine in Photoshop. With film you try to test with instant film or plan and meter very carefully so you can get it all on one sheet of film, and maybe use more than one camera for a few variations, because it may require shooting one exposure while it's dark out, and one with window light, and you only get one or two chances per day. Each exposure gets different filtration, so you might use tungsten film, shoot the tungsten exposure while it is dark out, wait for the sun to come up, put an appropriate orange (85 ser) filter on the camera, turn off the tungsten lamps, and make the daylight exposure (or alternately, do the reverse process in the evening).

 

[Valentin Arfire]

light torment...

Thank you friends for the advices.

Of course my photographic skills are far from good so I need all the experience I can get so your advice is invaluable.

My panorama shooting consists in the following: I try to careful choose a station point from which I see some good details on several directions, have a good dynamic and not too much troubles (I hate scaffolds and mesh covered buildings) and when it comes to impredictable behavior/movement from certain directions I take several shots so that some may be used for certain details and other for others. Of course I shoot raw and often aeb, when it comes to the limited dynamic of the sensor and mixed light sources. The beginning of panorama photography states that all shots must be with the same exposure conditions regardless they are pointing towards the sun or to some shadow area.
With tufuse pro I actually can make several different panoramas and then fuse them together with some remarkable results, but unfortunately there is little prediction on how long it will take the processing while the batching is very unlikely to solve all issues.

Of course it would be impossible to adapt studio-solutions to very different problems when it comes to different light conditions.
For instance I can imagine what a museum curator might say when ask the permission to change the light bulbs or attach some filters on the windows.

regards,

 

[Michael Fontana]

Any automatic solution would require AI which determines what is illuminated by what light, and would most likely make a lot of mistakes.

Exactly, there's no alternative to the photographer's eye.
Finaly, he decides about the image/stitch/pano and not the soft/hardware.

David, you can't usually use flashes for QTVRs, as they will become a parth of the image.
If you wan to displace' em, it will have different shadows/lights.

 

[Valentin Arfire]

http://www.europhoto.ro/valentin/BCN/street/streetscape-night-j.html

here's an example of "now I give up" with no intervention.
probably by tomorrow with a lot of processing the lights would seem better and the dusk more dramatic.


regards,

 

[Michael Fontana]

Valentin
did you stitch the RAWs on that one?

 

[Valentin Arfire]

yes of course - 5D cr2;
Tokina 10-17 lens set at 14.5 mm
ISO 100
aperture 6.7
time: 4 seconds


dpp settings: daylight; neutral

then CA correction in ptlens
results jpg files of approx 2 MB each

stitched with PTGui - results a 40 MB uncompressed jpg of 10420x5211 pix.
(the tiff has better colors but for practical reasons I can't afford to work on huge tifs)

then cubefaces with pano2qtvr to correct the tripod
(I usualy have here a small sharpening step)

in the end photoshop elements 6 I use
to resample to 4000x2000 pixels, reduce noise, light balance (shadow/highlights)
and saving with a 9 (out of 12) jpg compression.


here is a sample out from the 40 MB original large jpg.

regards,

 

[Michael Fontana]

Valentin

there must be something wrong with your RAW-conversion/workflow, if the last, flat image is at 100%-crop. On one side, its close to be oversharped, meanwhile on the other side, there isn't any real sharp parths. Tecnically, there isn't a difference that big to my 1 Ds-2 files, but I never saw such a IQ.

I could imaging, when working with PTGui's output as jpg and saving it multiple times, you might get that sort of effect.

So tiffs might be the solution, but that's not what you want....

Saving jpgs multiple times creates artefacts, loss of original image data, etc

 

[Valentin Arfire]

tif only versions

Hello friends

I stitched again the panoramas - starting from the raw but avoiding any jpg, sharpening or filter.

There were 3 resulting 4000x2000 equirectangular tif files of approx 31255 kB each that afterward I fused together with tufuse pro; think it would be nice to share this with you.

Indeed any jpg has a big price in wasting colors and details.

this workflow:
dpp from Canon (converted to uncompressed tiffs) for daylight conditions, tungsten and click to choose grey - I tried to choose some neutral from the walkway.

ptlens to correct the color aberration from tokina fisheye lens

ptgui to stitch the images at the final size : 4000x2000 pixel (luckily I had the dots from the prior project, so there wasn't much time with that)

pano2vr to make the swf film as well as the html page with an 80% compression so that the final file would be somewhere around 1 MB. I put a limitation of angle from 40 to 110 degrees

http://www.europhoto.ro/valentin/test/c/click_out.html

http://www.europhoto.ro/valentin/test/t/tungsten_out.html

http://www.europhoto.ro/valentin/test/d/daylight_out.html


and here are the fused ones (each pair of resulting images)

http://www.europhoto.ro/valentin/test/dc/output-dc_out.html


http://www.europhoto.ro/valentin/test/dt/output-dt_out.html


http://www.europhoto.ro/valentin/test/tc/output-tc_out.html


... and all three fused together
http://www.europhoto.ro/valentin/test/dtc/output-dtc_out.html

thank you for your time and interest

 

[David A. Goldfarb]

David, you can't usually use flashes for QTVRs, as they will become a parth of the image.
If you wan to displace' em, it will have different shadows/lights.

Sorry, I missed that this was for QTVR. In any case, though, the kinds of slave flashes that I'm suggesting replace bulbs directly (if that is an option logistically), and illuminate the space in the same way but brighter and at 5500K, so if you can have the incandescent lights, you can have these kinds of strobes. Click the link that I posted, and you'll see what I mean. They're a fairly standard tool for photographers who shoot architectural interiors and want to be able to photograph the interior lighting in an authentic way.

 

[Michael Fontana]

Sorry, I missed that this was for QTVR. In any case, though, the kinds of slave flashes that I'm suggesting replace bulbs directly (if that is an option logistically), and illuminate the space in the same way but brighter and at 5500K, so if you can have the incandescent lights, you can have these kinds of strobes. Click the link that I posted, and you'll see what I mean. They're a fairly standard tool for photographers who shoot architectural interiors and want to be able to photograph the interior lighting in an authentic way.

David, I don't have exactly these ones, but some daylight = blue bulbes, not strobes.

Today with digital, I leave very often my 20'000 Ws of studio torches at home and work with available light only. Years ago, you needed tons ofs light, for bigger rooms.

I still rember having spent 8 hrs of lightning only in one single room, with about 10 strobes; a little patio provided the only light of the entire appartement, and of course, there were big glass windows towards it ..... reflections .... ;(

the photo finally looked fine, but completly unauthentic, in terms of the architects light and space ;-)

But no other way to do it.