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Freedom from Filters (here lies heresy)

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Guy-

 

Of course, I can't seem to find the message (probably Scott's, I'd guess) where someone measured the vignetting correction and found it to be much less with IR correction on also...in fact, someone also menitoned that this could be seen as a "feature", if you wanted more or less vignetting built into your shot!

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Guy -

from one of Scott's posts from May 1:

Right now the M8 firmware puts a strong L vignetting correction plus a weak A channel correction into the ON behavior, and puts a weak or nonexistent L vignetting correction and a stronger, pretty well lens-calibrated correction (see Sean Reid's results, and one of my posts about a week ago) into the ON+UV/IR behavior. When the firmware doesn't get things quite right, you can end up with slight over or under corrections of the A channel and need either a lot more help to reduce L vignetting, or small adjustments to reduce over corrections (from using ON without the UV/IR). This means that the PP requirements really separate into L vignetting and A vignetting corrections.

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Hi Jono,

 

Of course, none of us needs anyone's OK to photograph as we like. Heck, if someone wants to shoot textiles with an M8 but no filter, who are we to object? It's useful to know that mounting an IR-cut filter on an M8 lens will (generally and assuming good color profiles) provide more accurate color (color that has fidelity to the subject) than working without it.The photographer can then decide whether or not that accuracy (to the degree that such can exist) is important or not.

 

As far as I'm concerned, its OK to paint the whole camera orange and shoot with lenses made from bottles. If a client is paying for something, then they need to get what they asked for. Otherwise, photographers should do whatever they want.

 

Cheers,

 

Sean

HI Sean and Guy as well.

You seem to be telling me that I can do what I like, and that colour is subjective, and it doesn't matter if it's wrong if I like it.

BUT

I'm quite convinced that for much greenery(but not all) the Leica is MORE ACCURATE WITHOUT THE FILTER it isn't just in Aperture - you can see the blue flush on the LCD as well.

I'm not claiming the right to get it wrong - I'm claiming that in most circumstances for landscapes, and especially with the latest firmware, the camera get's it better without filters.

If you add in the problem with the cyan drift, I think there is a real argument, not just that the colours are 'nicer', but that they can be more accurate without a filter.

 

Just to get that clear

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Guy -

 

And more on this at http://www.l-camera-forum.com/leica-forum/leica-m8-forum/21587-results-we-want-see-results-1-a-4.html , on page 4 of the post.

 

He is looking at color vignetting in the various channels, and I have to admit that I'm not sure if he is describing an effect that would be seen as overall vignetting when you add it all up or not...

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Guest guy_mancuso

Thanks Steve I never tested just the ON feature since i always have the ON/IR filter, i will have to look into this some more , really pretty interesting.

 

 

Jono i agree and i don't doubt you for a second when it comes to foilage because foilage actually does something with the IR light and other things do not a house, car etc etc. The effect you are seing maybe a desired one without the filters and it maybe your part of the world and the types of grass and foilage . In other parts of the world it maybe different. You know how we talk about rendering of blue sky for example here in the Southwest it is royal blue but in other parts of the World a blue sky will render differently because of longitude and lattitude difference and seasons. i think the way to look at this is foilage will always be a variable for a landscape shooter so depending on the enviromental conditions foilage will render differently with and without the IR blocking in different places. For instance i mentioned here in the Southwest almost everything is yellow green including our grass but in Kentucky grass is blue green now i would bet a dozens donuts the IR absorbtion or reflection is a completely different value and maybe one would render better with a filter and one without.

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HI Sean and Guy as well.

I'm quite convinced that for much greenery(but not all) the Leica is MORE ACCURATE WITHOUT THE FILTER it isn't just in Aperture - you can see the blue flush on the LCD as well.

I'm not claiming the right to get it wrong - I'm claiming that in most circumstances for landscapes, and especially with the latest firmware, the camera get's it better without filters.

If you add in the problem with the cyan drift, I think there is a real argument, not just that the colours are 'nicer', but that they can be more accurate without a filter.

 

Just to get that clear

 

Hi Jono,

 

Without a proper color profile for the filtered pictures one can't fairly compare the two. The converters you are using, to the best of my knowledge, do not have color profiles designed for the M8+Leica IR-cut filter. Absent that, there's no way to make a fair comparison.

 

If one were to say, "Given the color profiles now available in RAW Converter X, I see more accurate color without the IR filters (than with) when using RAW Converter X...." that might well be true.

 

One fair comparison, at the moment, would be:

 

no filter - coded lens - C1 with generic M8 profile

Leica filter - coded lens - C1 with M8 + IR filter profile

 

There are also other color profiles for the M8 and some may be optimized for the Leica filters. I don't know about those first hand.

 

In short, the profiles (or lack thereof) can be a confounding variable in any comparison.

 

Cheers,

 

Sean

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Thanks Steve I never tested just the ON feature since i always have the ON/IR filter, i will have to look into this some more , really pretty interesting.

 

The examples are on the site if you want them.

 

Cheers,

 

Sean

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Guy -

 

And more on this at http://www.l-camera-forum.com/leica-forum/leica-m8-forum/21587-results-we-want-see-results-1-a-4.html , on page 4 of the post.

 

He is looking at color vignetting in the various channels, and I have to admit that I'm not sure if he is describing an effect that would be seen as overall vignetting when you add it all up or not...

 

That was just a cute example of pink corners, the result of applying 1.102's strong red vignetting correction when only a little was needed. A more recent post, with perhaps a clearer description, is found here.

 

For a sensitive analysis, I have been plotting just the green channel intensity to check for overall vignetting, and the ratio of the red channel to the green channel intensities to check for red vignetting and to see what corrections are applied. I end up with curves, which are noisy but accurate, and I have only one coded lens (plus some nail polish and jlm mounts) to work with at the moment. Check out Sean's site for lots more coded lenses (and more nail polish), with results shown as images, to give a sense of what you might care about in practice.

 

scott

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C1 has the features for the cyan correction built in. But they're only activated for C1 backs.

 

If people here were willing to pay decently I could write something that does the corrections.

 

Edmund

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Hi Jono,

 

Without a proper color profile for the filtered pictures one can't fairly compare the two. The converters you are using, to the best of my knowledge, do not have color profiles designed for the M8+Leica IR-cut filter. Absent that, there's no way to make a fair comparison.

 

If one were to say, "Given the color profiles now available in RAW Converter X, I see more accurate color without the IR filters (than with) when using RAW Converter X...." that might well be true.

 

One fair comparison, at the moment, would be:

 

no filter - coded lens - C1 with generic M8 profile

Leica filter - coded lens - C1 with M8 + IR filter profile

 

There are also other color profiles for the M8 and some may be optimized for the Leica filters. I don't know about those first hand.

 

In short, the profiles (or lack thereof) can be a confounding variable in any comparison.

 

Cheers,

 

Sean

 

Hi Sean

I take your point, but neither Lightroom or Aperture have colour profiles anyway - you make your own presets, or use the camera default preset - the whole concept is different in that you are working with the RAW file rather than doing a conversion. Following your argument you must use C1 to make any sensible comparison. I admit to not having used C1 at all with the latest firmware, largely because I didn't like the colours I got with any of the profiles - especially greens (and I did spend a lot of time with it in the early days) but also because I don't like the workflow.

 

It's not really possible to make scientific comparisons in mixed lighting anyway - and even if you did, it would have to be different for each scene, each plant etc. etc. I think my tests with prints taken out and placed next to the foliage itself as about the best I can manage. You certainly can't use colour checkers - because they don't reflect infra red like foliage.

 

Still, my point holds (in my opinion of course) for Lightroom, for Aperture, and for the LCD on the back of the camera!

 

Your 'fair comparison' doesn't really do anything other than give you an opportunity of comparing C1 profiles, which may be useful for those using C1 . . . . . .

 

I think that taken to it's logical conclusion your argument means that one can't have a valid empirical discussion about colour response outside - I'd probably agree, but it isn't terribly helpful!

 

I spent a lot of time fighting cyan drift in the Kodak SLR/n, where I did some work with Kodak in Rochester on the firmwere, and where the camera had lots of extra information about aperture etc. and I know how difficult it is for landscape work.

 

I'm simply trying to make people think hard about the clear attitude around here which is that you bung on the filters and forget it.

 

Once again however, I'll emphasize that I'm talking about using the camera for natural lighting where you aren't expecting to come across synthetic fibres.

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Jono i agree and i don't doubt you for a second when it comes to foilage because foilage actually does something with the IR light and other things do not a house, car etc etc. The effect you are seing maybe a desired one without the filters and it maybe your part of the world and the types of grass and foilage . In other parts of the world it maybe different. You know how we talk about rendering of blue sky for example here in the Southwest it is royal blue but in other parts of the World a blue sky will render differently because of longitude and lattitude difference and seasons. i think the way to look at this is foilage will always be a variable for a landscape shooter so depending on the enviromental conditions foilage will render differently with and without the IR blocking in different places. For instance i mentioned here in the Southwest almost everything is yellow green including our grass but in Kentucky grass is blue green now i would bet a dozens donuts the IR absorbtion or reflection is a completely different value and maybe one would render better with a filter and one without.

 

Hi Guy

Of course you're right, but it isn't just areas, it's different lighting (sunshine / time of day) and of course different plants. Sean quite rightly implies that you cant really do a proper objective assesment.

 

But we all have our different experiences and expertise. I've taken at least 10,000 shots of landscape and nature in the last 6 months, nearly all in colour, from Greece to the Alps to Scotland, Cornwall and eastern England I've made big prints and exhibited them. I wouldn't be deciding not to use filters out of bloody-mindedness, especially as it's taken so much time and effort to get a complete(ish) set of filters, and to get most of my lenses coded.

 

Of course I'm not telling people NOT to use filters either, just that if you do the same sort of stuff I do, then it's worth examining the situation rather than simply taking the plunge and committing oneself to coded lenses and cyan corners.

 

I've got some PR stuff to do later on this month, and a wedding (dammit) next month, and of course, I'll use the filters on everything for that.

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Jono,

 

Did you photograph landscapes in color before you started using a camera that is sensitive to IR? Were you happy with the results from the other digital or film cameras? Are you more pleased now with the colors?

 

Form my very limited observation of images that I've seen posted using the M8 without filters, my impression was that a lot of the shots of trees and foliage did not look "right" to me. Often the tree trunks and branches looked greenish rather than grayish so something seemed wrong to me. But for all I know, maybe they were greenish in the first place.

 

On this thread there are two comparison landscape pictures showing a pond and some trees. One was taken with an M8 the other is taken with a G7. It seems there is a difference between overall exposure on the two shots so a comparison for IR is difificult. There is no indication which camera produced which picture, but I like the one that has blue sky and darker green foliage. The other one loses the sky color, makes the water look dirtier, and the grass looks artificially bright. (Although I think the other shot could be improved by making the leaves and grass a tiny bit brighter.) Most likely, the one I don't like was shot with an M8 as that shot shows the effects of IR sensitivity. But this is just one man's opinion

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Hi Alan

Jono,

 

Did you photograph landscapes in color before you started using a camera that is sensitive to IR? Were you happy with the results from the other digital or film cameras? Are you more pleased now with the colors?

 

 

Yes Indeed:

Olympus E10 - soso

Nikon D1x - yellowish but okay

Olympus E1 - excellent

Nikon D200 - not so good (also quite sensitive to IR)

Kodak 14n/SLRn - excellent with work

Nikon D2x - pretty poor

Nikon D200 - better, but not so much better

Epson R-D1 - pretty good - especially the jpgs (but it is quite sensitive to IR)

 

I have a library of some 20,000 digital landscapes (and lots more film) landscapes - and that doesn't count the much larger quantity which have been thrown away. Getting good quality greens has always been much the largest challenge - only the Olympus E1 got it 'right' without a deal of tweaking.

 

I have a modus operandi with the M8 which gives me better colour than with all but the E1 - about equivalent to the 14n/SLRn (on which I did some firmware testing and feedback with Rochester, specifically on cyan shifts - spreadsheet after spreadsheet with rgb values across frames) - it's one reason why I'm so wary of using filters, as I've spent so much time fiddling with cyan casts - the problem was never completely solved on the Kodak, even though the camera had much more information than the leica can ever have. There was also a lens table, where you took shots of a white background at various apertures, and the camera stored these values so that it could use them to correct cyan/magenta casts - of course, the Leica doesn't know the aperture value, but the cyan certainly changed with it. The problem is slightly different with the Leica, but I'm very sceptical that it can be cured as easily as knowing what the lens is.

 

Form my very limited observation of images that I've seen posted using the M8 without filters, my impression was that a lot of the shots of trees and foliage did not look "right" to me. Often the tree trunks and branches looked greenish rather than grayish so something seemed wrong to me. But for all I know, maybe they were greenish in the first place.

 

You have to do some work either way - generally speaking a little tweak of the yellow hue is all that's required, but you have to do something for most lighting conditions.

 

On this thread there are two comparison landscape pictures showing a pond and some trees. One was taken with an M8 the other is taken with a G7. It seems there is a difference between overall exposure on the two shots so a comparison for IR is difificult. There is no indication which camera produced which picture, but I like the one that has blue sky and darker green foliage. The other one loses the sky color, makes the water look dirtier, and the grass looks artificially bright. (Although I think the other shot could be improved by making the leaves and grass a tiny bit brighter.) Most likely, the one I don't like was shot with an M8 as that shot shows the effects of IR sensitivity. But this is just one man's opinion

 

My understanding was that the shot with the blue sky was taken with the M8 - but it's a crazy comparison either way, one is clearly overexposed.

 

I'm not nearly as technically accomplished as many around here, but this thread isn't something I stepped into lightly. I realised that I'm definitely swimming against the flow - I just wanted people to stop and think before they made a blanket filtering decision. I was also aware that for many serious photographers who had already made the decision, it would destroy whatever credibility I might previously have gained. Incidentally - Leica make it pretty clear that you don't need filters for all occasions (FWIW).

 

One of the reasons I haven't posted comparisons, is that it's impossible to deal with the differences in different people's colour management and browser response - and anyway, converting it all to srgb doesn't do anything the best of favours!

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...Epson R-D1 - pretty good - especially the jpgs (but it is quite sensitive to IR)...

My R-D1 and R-D1s jpegs look rather poor, raws are much better, and i haven't got IR problems more than 3 or 4 times in 2 years 1/2 (about 7,000 pics).

Also i've used Leica UV-IR filters on Leica lenses with them and colours look natural so far.

But i only use the Epson raw converter, perhaps it comes from this i don't know.

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On this thread there are two comparison landscape pictures showing a pond and some trees. One was taken with an M8 the other is taken with a G7. It seems there is a difference between overall exposure on the two shots so a comparison for IR is difificult. There is no indication which camera produced which picture, but I like the one that has blue sky and darker green foliage. The other one loses the sky color, makes the water look dirtier, and the grass looks artificially bright. (Although I think the other shot could be improved by making the leaves and grass a tiny bit brighter.) Most likely, the one I don't like was shot with an M8 as that shot shows the effects of IR sensitivity. But this is just one man's opinion

 

Yeah those are mine and the G7 shot is clearly a throwaway (it's the overexposed one) but I thought it showed decent colors in the M8 shot which is why I put them up at all.

 

It wasn't meant so much as a comparison as it was to say that I thought the M8 without a filter still did a far better job than the G7 under nearly identical circumstances.

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- you can see the blue flush on the LCD as well.

 

Hi Jono,

As you know, I've been looking for your "Blue Flush" ever since you mentioned it and today I had some sunshine to explore. What I found was that the Leica UV/IR filter seems to shift the WB, so that the presets don't render the same, as no filter. Of course, you can see this easiest with JPEG and the daylight/cloudy/shadow presets, but playing with the Kelvin scale, I found that about 7300° for daylight removed a hint of blue and brought the greens back to reality. I also shot with and without the filter and calculated the "absolute difference" to see what the filter was affecting. It was affecting almost everything and that may have been the WB shift in addition to the IR removal.

Now, I like warm tones, so the 7300° Kelvin is still too cool for my tastes. If you still have your Greek images, check to see if a higher Kelvin will fix the Peloponesian Blue situation.

Bob

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It wasn't meant so much as a comparison as it was to say that I thought the M8 without a filter still did a far better job than the G7 under nearly identical circumstances.

 

I guess I didn't understand the point of the post of those two images. Especially with the over-exposure on one. I've never used a G-7 but my little Canon SD800 records blue skies and green leaves and grass quite well when the exposure is accurate. At least the G7 shot made it clear that the (cherry? or dogwood?) trees were in bloom so we had a color reference there. But how did you measure the quantity of IR in the scene in the first place? Maybe there wasn't much or this type of foliage doesn't reflect much.

 

Forget the comparison to the G7. The M8 shot unfiltered looks fine to me and doesn't seem to show any "noticeable" or objectionable signs of IR affecting the image if there is any affect at all.

 

In general, I'd suspect that landscape shots are where the filters would be needed the least. The colors in a landscape are often subjective and could always be adjusted to look pleasing to most viewers. And even if something black turned magenta, one typically wouldn't notice. And if an object in the scene actually was magenta and became de-saturated as a result of overall color adjustment or via a profile, that too would probably go unnoticed in many cases.

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Forget the comparison to the G7. The M8 shot unfiltered looks fine to me and doesn't seem to show any "noticeable" or objectionable signs of IR affecting the image if there is any affect at all.

 

Exactly, and that was my only point in posting. Probably should have left out the G7 snap as it seems to have confused the issue. Sorry 'bout that!

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I think you need a better 5D - and my profiles for 5D, maybe. When I profiled the 5D I bought a $100 lens, and the sharpness and color tone blew me away (50/1.8). And as you know I own a 1Ds, a 1DsII and some of the best Canon glass. In fact, it was so good that I'm thinking of using a 5D for travel.

 

Edmund

 

Hey Edmund,

 

I don't know quite what to tell you. I've got a couple of 5ds here, and yeah, they're fine. But they certainly don't seem as sharp to me as the M8 files. Maybe you need a new M8

 

(And please don't take this as 5d bashing. It's a great camera! And the 50 1.2L is a wonderful lens. After f2.8 it's nearly as good as the 50 Summilux at 1.4

).

 

On topic now, this weekend's wedding was a Greek Orthodox wedding in Toronto, and I used the 5d and M8 exclusively (the DMR did not make an appearance this weekend, but will soon).

 

Most of my lenses had filters, some didn't, notably my 75 Lux. So I was in the land of synthetic black & tungsten with the M8! When I get a chance, I'll post some stuff.

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Exactly, and that was my only point in posting. Probably should have left out the G7 snap as it seems to have confused the issue. Sorry 'bout that!

Hi Joe

Well, I thought it was useful, and perhaps more so in that you didn't say which was which!

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