p.1 #3 · 5d2 highlight tone priority/auto lighting
I just got my 5dm2 yesterday.. im having some processing issues..lightroom shows red greed halos around the highlights. processed in dpp there is no problem..this could be the highlight tone priority or the lighting optimization that on .. or maybe lightroom needs and update for raw 5dm2 files.. I dont know..im keeping those settings off for now.
p.1 #5 · 5d2 highlight tone priority/auto lighting
ChrisDM wrote:
I shoot RAW so I leave the HTP off. It only affects JPGs... And my "auto lighting optimiser" is my set of graduated ND filters
Chris Miller
www.imagineimagery.com
As far as I'm aware HTP does effect Raw images, it also sets the minimum iso to 200. I've used it in situations of high contast and it seems to work well, keeping the highlight details.
To prove it take a shot with & without HTP.... & look at the resulting on screen histogram.
The trade off is slightly more shadow noise, which can be easily removed at processing in LR or DPP.
p.1 #6 · 5d2 highlight tone priority/auto lighting
I don't like the Highlight Tone Priority feature because (a) it defaults to ISO 200 and (b) it increases noise in the shadow areas. I've looked at some web samples and I am not too impressed by what it can do. If I shoot a lot of whites like wedding dresses it may be another story. I am not sure (yet) exactly what Auto Lighting Optimizer does. For now, I have both turned off.
p.1 #7 · 5d2 highlight tone priority/auto lighting
Locheil wrote:
As far as I'm aware HTP does effect Raw images, it also sets the minimum iso to 200. I've used it in situations of high contast and it seems to work well, keeping the highlight details.
To prove it take a shot with & without HTP.... & look at the resulting on screen histogram.
The trade off is slightly more shadow noise, which can be easily removed at processing in LR or DPP.
HTP only affects the RAW file if you view/edit in DPP (which I don't use). The reason you see a change in the histogram in-camera is that the histogram is a representation of the embedded jpg. To prove this, you can also watch the histogram shift between "Picture Styles", which is of course another JPG-only in-camera manipulation, even if you're shooting "RAW only" (there is still an embedded jpg in every RAW file.
The bottom line with all of these in camera edits is that no matter how useful and convenient they may be, a better job can be done in post processing. This is because each image is unique, and can be treated as such in post editing. But in-camera manipulation settings treat every image you take with the exact same settings/processing, whether it needs it or not.
p.1 #8 · 5d2 highlight tone priority/auto lighting
bobbytan wrote:
I am not sure (yet) exactly what Auto Lighting Optimizer does. For now, I have both turned off.
Yeah it would be nice for a technical discussion of what these things do and exactly what they affect. I took a backlit shot of a bronze statue yesterday - turned on HTP and the reflection from the bronze still got fried. I do my processing in Lightroom so I tend to think that Chris is right (as Wikipedia sez, "citation needed") about it only being used in DPP.
As far as the shadow noise - what this implies is that the shadows get bumped in post. That implies the levels are simply raised by adding a numerical constant of some sort. Since teh shadows are contained in the least # of bits you get noise. You should be able to counteract that by simply dragging them back down again. Same net result.
p.1 #9 · 5d2 highlight tone priority/auto lighting
HTP only affects the RAW file if you view/edit in DPP (which I don't use). The reason you see a change in the histogram in-camera is that the histogram is a representation of the embedded jpg. To prove this, you can also watch the histogram shift between "Picture Styles", which is of course another JPG-only in-camera manipulation, even if you're shooting "RAW only" (there is still an embedded jpg in every RAW file.
The bottom line with all of these in camera edits is that no matter how useful and convenient they may be, a better job can be done in post processing. This is because each image is unique, and can be treated as such in post editing. But in-camera manipulation settings treat every image you take with the exact same settings/processing, whether it needs it or not.
Chris Miller
www.imagineimagery.com
Hmmmm...ok Chris I get your drift.... I thought the HTP switch actually made a software change to the sensor sensitivity settings of the sensor itself, hence the reason the ISO defaulted to 200iso.
Also manual states as you say "for RAW images, the contentof the settings in the camera can be applied when processed with DPP"... for Auto Light Optimizer....
It does not say that for HTP.
Just goes to show one thing , ... the Canon manual that comes with the camera it a big let down!
Note I found an interesting aritcle from Bob Atkins on HTP on the 40D found at :
" One way Canon might be doing HTP is to use some sort of amplifier with non-linear gain. Let's say you set the camera to ISO 200 with HTP on. You could then apply the gain of the ISO 100 setting (which may be a gain of 1) to the highlights (pixels with high values), but the gain of the ISO 200 setting to the shadows (pixels with low values). That would keep the highlights from blowing out while retaining shadow detail. You'd get the highlight detail of shooting with an effective -1 EC for the highlights, and the normal shadow detail for ISO 200 (no EC). It's possible you might then have to tweak the tone curve a bit for the best looking image.. This is just a guess of course, made on the basis of some forum and email discussions. It would explain why you can't use HTP at ISO 100 (if the "native ISO" of the sensor is 100, then there may be no gain applied at ISO 100, so you can't then apply less gain with HTP turned on!)
p.1 #10 · 5d2 highlight tone priority/auto lighting
According to Chuck Westfall and to Michael Guncheon (Canon EOS 5D Mark II, Magic Lantern Guide, p 193) "It actually changes the response curve of the image sensor". Obviously that would effect Raw and Jpeg. In my experience it has been helpful under certain wildlife shooting situations. I have avoided some blown highlights. I suppose this comes at some cost in increased shadow noise but in practice the saved highlights more than compensate for a bit of noise. If used judiciously, it is a very useful tool, particulary around white feathers or bridal gowns
p.1 #11 · 5d2 highlight tone priority/auto lighting
ALO can lead to unnatural results, it's pretty much just a shadow/highlight adjustment (which can lead to unnatural results) so it can reduce contrast, however on the flipside it often increases contrast in low contrast images
I leave it on, I'd say it works well in about 50% of photos that it has a visible effect on...not bad
p.1 #12 · 5d2 highlight tone priority/auto lighting
HTP definitely affects RAW.
When I received my first 1D3 at the end of 2007, Capture One was able to read its files but didn't yet correctly handle HTP: all those images taken with HTP set to "on" showed up underexposed by one stop. Only later did they update their software to automatically add a stop in post. LR did this correctly from the start, so you never saw it was on. Same for DPP.
Basically, that's what HTP is all about: underexpose by a stop... Only now we don't have to do it ourselves. It also explains the ISO 200 starting point.
Has the gas been turned of in the States like here in Europe 