HDR images using film

[emtor]

I'm posting here since the topic may somewhat be scanner-related.
Here's the question: Has anyone tried to make multiple slide exposures with the intent of creating HDR-images? With my DSLR I usually shoot three exposures,-at 0 EV, -2 EV and +2 EV. Scanning a frame of -2 EV will be problematic since the slide will be very dense in the shadow areas, but since it's the highlights I'm after in the -2 EV-frame, does it really matter wether the shadow details are lost or not? These will after all be present in the 0 and +2 EV frames anyway. Film has a wider range than digital, but I still find that the skies in landscape images could show some more detail. HDR (digital) is a useful technique in order to make the sky appear in the image the same way as I saw it when shooting the image.
So,-has anyone tried creating HDR-images with scanned slide-frames?

 

[jeongyun]

I have tried it with instant film (Fuji FP-100C).
Merged two shots.
http://www.flickr.com/photos/arty_lee/3844746222/

 

[sanking]

I'm posting here since the topic may somewhat be scanner-related.
Here's the question: Has anyone tried to make multiple slide exposures with the intent of creating HDR-images? With my DSLR I usually shoot three exposures,-at 0 EV, -2 EV and +2 EV. Scanning a frame of -2 EV will be problematic since the slide will be very dense in the shadow areas, but since it's the highlights I'm after in the -2 EV-frame, does it really matter wether the shadow details are lost or not? These will after all be present in the 0 and +2 EV frames anyway. Film has a wider range than digital, but I still find that the skies in landscape images could show some more detail. HDR (digital) is a useful technique in order to make the sky appear in the image the same way as I saw it when shooting the image.
So,-has anyone tried creating HDR-images with scanned slide-frames?

Why not just use color negative film? It has much greater dynamic range than slide film, usually has higher resolution when ASA is the same, and grain with modern color negative films like Portra 160 and Ektar 100 is virtually non-existent. I have exposed color negative film in inside/outside situations where the subject brightness range was 14-15 and was still able to scan the film and adjust the highlights and shadows to make a good print.

So from my perspective shooting color slide film with the intention of merging several exposures to get a HDR image is just creating a problem to solve an issue that already has a solution in another methodology.

Sandy King

 

[glhs116]

I am currently experimenting with film HDR. I'm finding much of the same difficulties that present themselves everywhere with HDR. Firstly, there just aren't that many scenes with such a range (scenes, I mean, that will benefit from not having black go black and white go white). Secondly, it is hard to make the effect look natural.

With all that said, I've had some success cleaning up some of my images where there was a large brightness range. The negative film captured the full range, the single scan on the Coolscan brought the full range into the digital realm. However, the extremes were at the extreme ends of the digital file and looked grainy and noisy when processed. In such a case, I have found combining the normal exposure with one that is deliberately overexposed (at the scanning stage, I mean -- two scans) allows a much cleaner rendering of the dark parts.

See this image and follow the links to previous attempts at scanning it:

http://www.flickr.com/photos/samagnew/5041102905/

 

[glhs116]

Obviously, if one finds a successful workflow, the great advantage that film HDR potentially has is that it removes the great "moving subjects" problem that digital HDR has. Whereas the digital photographer needs to expose the actual scene three times, we only need to scan the exact same piece of film three times.

I'd love to hear of any good HDR tutorials. I seem to be a pretty poor student so far.

 

[timparkin]

I've made a few HDR style combinations, where I've exposed the A sheet and got the highlights but not enough shadows and then pushed the b sheet.

I've also taken one or two shots where I have intentionally over exposed a frame to give me shadows to use.

Finally, I've also scanned using my Howtek drum scanner with Aztek DPL using a photomultiplier op-amp setting that gives me great shadow detail (i.e. most of the 12 bits are deep in the shadows) and a highlight op-amp setting (i.e. the 12 bits are distributed 'correctly') and combined the two to create a pseudo 20ish bit image. I haven't seen another single pass scan that gets such shadow quality without busting highlights.

Merging images is pretty simple and as long as you don't try something silly, i.e. keep it to just providing a boost in the deep shadows, then the results just look like the transprency on the lightbox, just with some great tonal shadows.

The results look nothing like negative film and negative film has a very different quality in the highlights and shadows that I sometimes don't want.

Here is one image that needed the blended exposure technique

http://www.flickr.com/photos/timparkin/4746343579/

and here is one that was the result of two different exposure curve scans.

http://www.flickr.com/photos/timparkin/4842457532/

I read nearly 11 stops of difference between the sky at the top and the deep shadow and I used a three stop grad. Velvia has an amazing dynamic range if you drum scan it (I get about 7.5 stops) where nearly all of it is usable (at least 7 stops of top quality) whereas Portra NC has about 9 stops but I'd say only about 8 stops at top quality.

I need to test more but I continue to be amazed at how much dynamic range velvia actually has (if you can get at it)

Tim

 

[pellicle]

Hi

one of the issues in making HDR with film is the issue of linearity. This is easier to solve (programatically) with a sensor than with film. As Sandy points out negative (colour but especially black and white) often does quite an amount of the range that HDR does and is perhaps why well handled HDR looks like well handled negative. I agree also that using chromes for this is not the easiest way.

Also for the longer exposures (the dark parts) negative has issues with being even more non-linear (reciprocity failure)

In this blog post I compare and examine a few of the issues:

http://cjeastwd.blogspot.com/2008/02/while-hrd-is-all-rage-ive-taken.html

Personally I like HDR when there is a need and application:

but sometimes its easier / only possible to use a single in which case colour negative is great stuff

http://cjeastwd.blogspot.com/2010/02/sun-over-shoulder.html

 

[pellicle]

Tim

I've made a few HDR style combinations, where I've exposed the A sheet and got the highlights but not enough shadows and then pushed the b sheet.
...

Here is one image that needed the blended exposure technique

http://www.flickr.com/photos/timparkin/4746343579/

and here is one that was the result of two different exposure curve scans.

http://www.flickr.com/photos/timparkin/4842457532/

those are some very nice results ... may I ask how you found registration from frame to frame when zooming in more? I found when I tried this that very subtle subject movement went from being blur (leaves are ok blurred a little) to being double images ... which was less attractive.

I like both of them a lot

 

[sanking]

but sometimes its easier / only possible to use a single in which case colour negative is great stuff

One of the attributes of color negative film is that it is virtually impossible to completely blow out the highlights. What happens is that the curve in the highlights, instead of continuing to increase in density as is the case with B&W film, first shoulders and then flattens out. This means that you can easily capture the entire range of subject brightness range recorded by the film.

Now, if you were printing in the wet darkroom it would be impossible to print a negative with this range and get adequate contrast in the highlights. But you can scan a negative like this and then tweak the contrast in the flat part of the shoulder. Also, if you scan in RGB you can use selective filtration to give an even longer dynamic range.

In 2007 I made a long exposure in one of the Yungang Caves near Datong. The difference in subject brightness range between the light in teh cave and outside was more than 20 stops. However, I was able to scan the negative and work it in such a way that detail was captured in the deepest shadows inside the cave and one a part of the rocks outside in full sun. I was amazed by this but it sure gave me a good indicator of the potential of color negative film.

Sandy

 

[Tony-S]

Sandy, I'd sure like to see that image if you could post it. That's truly amazing that you can get that many stops. What film were you using, and if B&W how did you develop it?

Also, what do you mean by "scan in RGB"? Is this something that can be done with VueScan?

Thanks,

Tony

 

[sanking]

Sandy, I'd sure like to see that image if you could post it. That's truly amazing that you can get that many stops. What film were you using, and if B&W how did you develop it?

Tony

Tony,

Here is the image. It was shot with Portra 160 VC and the exposure, based on the shadow values, was somewhere between five and ten minutes at f/22. The light on the side of the rock at the upper left is outside and in full sun. In order to make a good image of the negative I used the filters in Photoshop in making the conversion to B&W, then I adjusted the tonal values to add contrast in areas that were flat.

It was pretty dark in there, so much so that you had to use a flashlight to adjust the camera. It actually would have been much easier to shoot the scene with a B&W film and develop in a two-bath solution to control the highlights, but I did it in color and had to go from there.

Sandy

 

[emtor]

http://cjeastwd.blogspot.com/2010/02/sun-over-shoulder.html

The pics of the sun settles it for me. I'm going color negative film for some of the images I'm shooting . . . thanks,-you just saved my day.
Digital burns out in the highlights very easily, and even HDR-images made up from 11 different exposures burn out. Not only does the sun burn out, but snow also suffers from blown out areas. Looking at your images I can tell that one color negative frame handles highlights better that 11 digital exposures combined. So, what kind of color negative film are you using?

 

[Tony-S]

Tony, Here is the image.

Holy cow Sandy, that's remarkable. Looks like I have an assignment to do. I don't have any 160VC, but I do have Pro 160S. I understand they have about the same dynamic range capabilities?

Thanks,

Tony

 

[pellicle]

Hi

The pics of the sun settles it for me. I'm going color negative film for some of the images I'm shooting . . . thanks,-you just saved my day.
Digital burns out in the highlights very easily, and even HDR-images made up from 11 different exposures burn out. Not only does the sun burn out, but snow also suffers from blown out areas. Looking at your images I can tell that one color negative frame handles highlights better that 11 digital exposures combined. So, what kind of color negative film are you using?

Fairly much all neg responds this way, as it happens I favour using Fuji 400 NC but that's just because I like the colours of it. Have a go with a roll of a few different ones and see how you go.


Its worth noting that if you scan negative as negative on many scanners you will get what appears to be clipped highlights due to the way the scanner software makes conservative assessments as to the point on the curve when "signal" ends and "noise" begins. I recommend more careful manual setting of the black and white points for each channel individually. Something like this:

http://cjeastwd.blogspot.com/2009/10/quick-negative-scan-tutorial.html

It happens that (for reasons I can't quite fathom) that the best control over this is given to the operator using the software to scan as if you were scanning positive (even if you are scanning a negative). Happily it is not difficult to invert and sort the image out.

After I have sussed out a given film I set up "actions" in photoshop to cope with this after scanning.

Enjoy the comming Nordic winter and I hope you pull through the dreary autumn time

 

[emtor]

Enjoy the comming Nordic winter and I hope you pull through the dreary autumn time

Hehe . . . won't be long before the dreary autumn time is over. Winter isn't far away here in Finnmark, Norway. For me color negs is the way to go, which also gives me another benefit of not needing to depend on a DSLR and frozen batteries, since film can be used with my Rolleicord and an old selenium exposure meter. Last winter was frustrating when the temperature went down to minus 45 centigrades. A fresh battery lasted just a couple of minutes before it died on me.

 

[pellicle]

Last winter was frustrating when the temperature went down to minus 45 centigrades. A fresh battery lasted just a couple of minutes before it died on me.

yeah I know where you're coming from ... we had a few cold days in Eastern Finland last year too ... my 4x5 camera is alluminium and I hate using gloves, but if you don't your fingers drop into pain quite fast.

I have tried keeping DSLR batteries in my coat but they still freeze pretty fast when put into the camera. For some reason they don't rebound with their charge when their temperature gets up again.

If you're using 35mm just advance gently and it'll be fine, but if its below -20C (air temp, not wind chill) the film can get "brittle".

Sorry to not be keeping this on topic with HDR images using film

 

[glhs116]

Just a note that the "clipping" when using the "negative" setting in scanning software doesn't seem to be nearly as much of a problem on a Coolscan 9000 with the Nikon Scan 4.0.2 software. I've found it sufficient to simply make two scans as normal negative scans for HDR. One which is auto exposed, one which is deliberately underexposed. The "auto" one will not normally blow the highlights (the software seems conservative in this regard).

I've seen the result pelicle got on his Coolscan 4000 at the "negative" setting and this is not my experience on the newer Coolscan.

Sam

 

[glhs116]

sanking, awesome and inspirational shot. If you used something like ColorPerfect to sort out the curves you might even be able to get that range and keep it colour. Now THAT would be something...