M8 lens coding needed for RAW?

[keithdunlop]

Long-time lurker and I'm finally picking up an M8 in a couple of weeks to compliment my Nikon wedding kit. I used to work exclusively with a pair of M7's and I'm eager to get back to RF shooting.

The two lenses I want to start off with are the new VC 28mm f/2.0 Ultron and a 90mm Summicron 2.0 pre-ASPH. Obviously these are not coded. I always shoot in RAW and have read somewhere that lens coding is not used by the M8 processing engine in RAW mode. If this is correct, then great. If not, then the only lens I would need to code is the 28, right? Why would there be any cyan vignetting in the 90mm? And, even if there is a little corner cyan in both lenses, why can't I just formulate an import developing preset in Lightroom to correct it instead of coding?

Thanks in advance for the advice, and I look forward to being a more active forum participant once I have the M8 in my hands.

Keith

 

[J. Borger]

There is no need to code the 90mm unless you want exif info in your files.
Just get a IR filter and shoot away.
For the 28mm you need a filter and coding which is not convenient with a non Leica lens in M mount. The LTM lenses (like the VC ultron 1,9) are easier to code using Milich adapters (do a google search for Milich adapters, the guy does not have a website). Coding with lenses 35mm and wider is needed for correcting Cyan drift.
Alternative would be to just use the IR filter on the uncoded vc 28mm lens and run a program called Cornerfix afterwards.
You can find the download link here:

http://chromasoft.blogspot.com/2008/01/cornerfix_15.html

Hope this helps!

 

[Bill Blackwell]

... For the 28mm you need a filter and coding which is not convenient with a non Leica lens in M mount. The LTM lenses (like the VC ultron 1,9) are easier to code using Milich adapters (do a google search for Milich adapters, ...

Why? John Milich will code any M lens flange for $25.

Email him at JM [at] milich [dot] com and he will reply with his latest pricing (and "how to do it") sheet.

 

[J. Borger]

Why? John Milich will code any M lens flange for $25.

Email him at JM [at] milich [dot] com and he will reply with his latest pricing (and "how to do it") sheet.

Because with LTM adapters there is no need to change the flange and you can just use a coded adapter, without the need taking the lens apart😉.

 

[baycrest]

I'm not too sure the design of the flange on the "older" Ultron.
There are 2 types. The older LTM has models have an "irregular" circumference which prevents milling (since there's no metal). The newer flanges have the same circumference size. These you can have milled.
Buying a new flange will set you back $150 versus $25 for the milling. JM has milling a few flanges Zeiss 28 & 35 and also CV 21 for me. As well I've purchased the flanges for my LTM CV 15 and Rollei 80.
He does a great job.
If you have a newer flange, you have the option of hand coding yourself, which I've done for my CV 35 f1.2
Best
Rob

 

[ChipNovaMac]

I am sorry.. but CV and John should join forces.... CV should give up on converting all the lenses to the M mount unless they have the pits needed for coding... otherwise CV should offer the lenses in the SM mount in order to use John's "coded" adapters!

Some of us are leery about taking an M mount off our lenses....

 

[keithdunlop]

I am sorry.. but CV and John should join forces.... CV should give up on converting all the lenses to the M mount unless they have the pits needed for coding... otherwise CV should offer the lenses in the SM mount in order to use John's "coded" adapters!

Some of us are leery about taking an M mount off our lenses....

I've often wondered this exact same thing myself. If Leica will not code third-party lenses, why are the other manufacturers (i.e. CV and Zeiss) not simply offering "M8 versions" of their lenses with milled and coded flanges? Is there some patent issue preventing the manufacturing of this one minor lens part? It certainly would not require any major retooling; just the addition of a program to an existing CNC machine to to cut the grooves. Myself, I would pay an additional $45.00 or so for a coded M8 version Zeiss lens.

 

[SR1]

Long-time lurker and I'm finally picking up an M8 in a couple of weeks to compliment my Nikon wedding kit. I used to work exclusively with a pair of M7's and I'm eager to get back to RF shooting.

The two lenses I want to start off with are the new VC 28mm f/2.0 Ultron and a 90mm Summicron 2.0 pre-ASPH. Obviously these are not coded. I always shoot in RAW and have read somewhere that lens coding is not used by the M8 processing engine in RAW mode. If this is correct, then great. If not, then the only lens I would need to code is the 28, right? Why would there be any cyan vignetting in the 90mm? And, even if there is a little corner cyan in both lenses, why can't I just formulate an import developing preset in Lightroom to correct it instead of coding?

Thanks in advance for the advice, and I look forward to being a more active forum participant once I have the M8 in my hands.

Keith

Keith,

I have a 28 zeiss and 90 elmarit (uncoded). There are issues beyond cyan vignetting if using UV/IR filters. I first noticed this when my car (silver) was included in a shot under a clear blue sky. The paintwork has a distinct blue cast, where as without the filter the colour of the car is registered correctly. I only shoot in RAW format.

The same problem occurs on both 28 and 90 lenses.

Unfortunately as my lenses still have to be coded, I can't tell you what difference it makes to the blue cast on silver paintwork.

Regards

SR

 

[jaapv]

Keith,

I have a 28 zeiss and 90 elmarit (uncoded). There are issues beyond cyan vignetting if using UV/IR filters. I first noticed this when my car (silver) was included in a shot under a clear blue sky. The paintwork has a distinct blue cast, where as without the filter the colour of the car is registered correctly. I only shoot in RAW format.

The same problem occurs on both 28 and 90 lenses.

Unfortunately as my lenses still have to be coded, I can't tell you what difference it makes to the blue cast on silver paintwork.

Regards

SR

I can tell you - it will be improved. However, a slight tweak in RAW conversion or using the correct profile in C1 or C4 will cure the problem without a trace.

 

[jaapv]

I've often wondered this exact same thing myself. If Leica will not code third-party lenses, why are the other manufacturers (i.e. CV and Zeiss) not simply offering "M8 versions" of their lenses with milled and coded flanges? Is there some patent issue preventing the manufacturing of this one minor lens part? It certainly would not require any major retooling; just the addition of a program to an existing CNC machine to to cut the grooves. Myself, I would pay an additional $45.00 or so for a coded M8 version Zeiss lens.

Patent issues forbid it. As it is, John Milich offers a flange milling service for self-coding (read - filling in with paint) and milled LTM-M adapters, as Baycrest notes. The sum of 150$ for a Zeiss flange seems a bit on the high side to me; I paid 26 Euro for one to Zeiss Germany about a year ago.

 

[SR1]

Jaap,

I unerstand that a filter needs to be used to deal with the IR issue as this cannot be corrected easily in post processing. I also understand that vignetting reduction can be achieved if the camera knows the focal length of the attached lens.

As the connection between lens and body is simply one of identification, I do not see how the coding can help to correct colour casts which differ in different lighting conditions if the canera is not set to AWB.

I leave my camera on daylight white balance and alter if necessary in photoshop. I prefer it that way.

The filter therefore cuts the IR and lets the camera produce a result which can be adjusted in software, be it vignetting or colour casts.

I am inclined to form the opinion that photoshop is the best place to do this adjustment and that coding is of little use on any lens if you like to decide on lighting temperatures and the extent of vignetting yourself.

After all both can be used to artistic effect.

Regards

SR

 

[jaapv]

Jaap,

I unerstand that a filter needs to be used to deal with the IR issue as this cannot be corrected easily in post processing. I also understand that vignetting reduction can be achieved if the camera knows the focal length of the attached lens.

As the connection between lens and body is simply one of identification, I do not see how the coding can help to correct colour casts which differ in different lighting conditions if the canera is not set to AWB.

I leave my camera on daylight white balance and alter if necessary in photoshop. I prefer it that way.

The filter therefore cuts the IR and lets the camera produce a result which can be adjusted in software, be it vignetting or colour casts.

I am inclined to form the opinion that photoshop is the best place to do this adjustment and that coding is of little use on any lens if you like to decide on lighting temperatures and the extent of vignetting yourself.

After all both can be used to artistic effect.

Regards

SR

No -the whole colour spectrum is affected by IR. The camera uses both the lens ID and the message "IR filter" in the menu to balance the colour for IR effects elimination. WB settings are irrelevant in RAW.

 

[victoriapio]

Patent issues forbid it. As it is, John Milich offers a flange milling service for self-coding (read - filling in with paint) and milled LTM-M adapters, as Baycrest notes. The sum of 150$ for a Zeiss flange seems a bit on the high side to me; I paid 26 Euro for one to Zeiss Germany about a year ago.

FYI - Correct. Zeiss will, however, replace the flange with another that brings up the correct frame lines on the M8. I bought a 21mm biogon from Popflash and they have very courteously, acted as the middle man in this conversion.

What is weird is that I also have a 21mm elmarit that is 6-bit coded but brings up the wrong flame lines on the M8.

It sure would be convenient if someone could offer a one-stop service that would 6-bit code a flange that brings up the correct M8 framelines.

 

[SR1]

No -the whole colour spectrum is affected by IR. The camera uses both the lens ID and the message "IR filter" in the menu to balance the colour for IR effects elimination. WB settings are irrelevant in RAW.

Jaap,

Granted that white balance in RAW is irrelevant at the point of capture, however the camera does not know the colour temperature you will ultimately choose. The best it can do is apply the one you last selected, and in the case of the 90mm elmarit with daylight setting on white balance, it gets the colour of my car wrong.

Also granted that coding the lens will help, however for those who don't want to post process, they clearly do need to code lenses above 35mm and the advise not to is simply wrong.

Once the IR cut filter has done its job, the rest is down to processing in an image editor, be it in camera or on computer. The computer has the advantage (or disadvantage depending on your view!) of having human input so each shot can be fine tuned rather than using a one size fits all package in the camera.

As the coding can only deliver 63 differnet permutations and those are all given over to identifying the focal length, nothing sophisticated is happening other than the mechanically achieved shift in IR entering the camera.

I really must get a lens coded to verify my assumptions, however the logic is sound.

If you want total control over your images, don't bother coding and sort out the resulting issues in photoshop etc.

SR

 

[jaapv]

The logic is not sound. It ignores the camera menu setting to coded+IR filter. Then the camera will apply IR correction prior (and vignetting correction) to writing the RAW data. WB is determined by the user at RAW conversion and has nothing to do with what the camera "knows". In a RAW workflow, the camera's WB setting is used for three things only: The camera LCD, the DNG thumbnail and the RAW converter's "as shot" setting. If you use camera Jpeg, obviously that will be determined by the camera WB too.
Coding has 189 permutations btw, not 63.
I have a feeling you do not see the distinction between RAW conversion (in ACR for Lightroom and Photoshop or any other conversion program) and postprocessing in, for instance, Photoshop, Lightroom, or any other program you care to name.

If you want to get quality colour images from the M8, there is but one way to go: Use IR filters, use coded lenses for all focal lengths under 35 mm (or use Cornerfix), shoot RAW and do colour balancing in RAW conversion. Use Photoshop etc. only for further processing and minor colour tweaks.
Another very important aspect: RAW-convert the files to 16 bit TIFF's for Photoshop, to avoid posterisation and other quality losses!
Start your workflow in the camera in aRGB, use that colourspace throughout and only convert down to sRGB at the very end of the process, just before saving for print. It is wise to save a 16-bits aRGB TIFF of the file first to revert to if needed. You can convert down to sRGB, but it is irreversible and you can never regain lost information by converting up to aRGB again.

 

[Gabriel M.A.]

The other day, about a month ago, a guy spotted my M8 as I was walking into a movie theatre. He said "oh, that's an M8, isn't it?" Yes, I said. "Don't you have to code the lenses so that you can take pictures?" I went on to explain as short and concisely as I could that it wasn't necessary at all, but that it helps.

He was surprised to hear it.

And it makes me wonder, how many other things keep on circling on- and offline of stuff that, in spite of many people rebutting misconceptions and misperceptions, these persist.

I guess the bashers own the soundbox.

And, to clarify (because you never know on these Internets, as a renowned genius called it) I'm not calling you (Keith) a basher.

I'm just amazed at the reach of the anti-Leica misinformation BORG collective.

 

[Gabriel M.A.]

If you want total control over your images, don't bother coding and sort out the resulting issues in photoshop etc.

I strongly advice against this background-less oversimplification. I've compared images with the same lens(es) coded and noncoded, and I would keep the coded one.

 

[SR1]

I am trying to answer Keiths question with a logical discussion and open reasoned throught.

I have nothing against coding and as I have said I really must get at least one of my lenses coded to see the result myself.

I object to the sugestion this is backgroundless oversimplification. How patronsing is that, not only to me but the silent majority reading this post and hoing to find reasoned and explained logic. I have tried to spell out my thought processes so people can make up their own mind.

Jaap,

The coding is 6 bit binary therefore 63 permutations. Are you calling the options of lens detection "on", "off" and "on+UV/IR" 3 groups of detection resulting in 189?

That's pushing a point as the camera still only receives 63 possible permutations from the camera. The other options are input by the operator.


I fully understand RAW conversion and I have already conceded that the camera does not atribute a white balance to the data. The fact remains that the camera registers the WB I set as my preferred and shows me that option when I open the image on screen.

If you are saying the coding allows the camera to "corrects" the RAW data before writing it to the SD card, then it is surely no longer RAW data.

The fact remains that the UV/IR filter corrects an issue which software cannot. Are we agreed on that?

If so, the further correction is done in software and I don't see why people shouldn't explore the possibility of seeing if photoshop etc can do a better job than the camera. There's no Leica bashing going on, just a search for an answer to a question posted.

I therefore think Keiths question was valid and whilst we may ultimately disagree on which is best (I currently have not done enough research to fully form my own opinion on this), I don't think it is helpful to dismiss such questions without letting others form their own opinions.

The autor of Cornerfix states that he developed it as an alternative to the one size fits all approach of the camera and if he can do it, why can't others?

Regards

SR

 

[sandymc]

Early on in the M8 IR saga, a number of folks did have some success in correcting for "cyan drift" using PhotoShop. But at the time, I think the consensus was that the results were visibly not as good as a for coded lens (or CornerFix for that matter) - it just turned out to be very difficult to match each lens's vignetting characteristics closely enough to get good results.

But there are a LOT of different ways to do things in PhotoShop, so perhaps a new approach will give better results....

Sandy

 

[HenningW]

I am trying to answer Keiths question with a logical discussion and open reasoned throught.

I have nothing against coding and as I have said I really must get at least one of my lenses coded to see the result myself.

I object to the sugestion this is backgroundless oversimplification. How patronsing is that, not only to me but the silent majority reading this post and hoing to find reasoned and explained logic. I have tried to spell out my thought processes so people can make up their own mind.

Jaap,

The coding is 6 bit binary therefore 63 permutations. Are you calling the options of lens detection "on", "off" and "on+UV/IR" 3 groups of detection resulting in 189?

That's pushing a point as the camera still only receives 63 possible permutations from the camera. The other options are input by the operator.


I fully understand RAW conversion and I have already conceded that the camera does not atribute a white balance to the data. The fact remains that the camera registers the WB I set as my preferred and shows me that option when I open the image on screen.

If you are saying the coding allows the camera to "corrects" the RAW data before writing it to the SD card, then it is surely no longer RAW data.

The fact remains that the UV/IR filter corrects an issue which software cannot. Are we agreed on that?

If so, the further correction is done in software and I don't see why people shouldn't explore the possibility of seeing if photoshop etc can do a better job than the camera. There's no Leica bashing going on, just a search for an answer to a question posted.

I therefore think Keiths question was valid and whilst we may ultimately disagree on which is best (I currently have not done enough research to fully form my own opinion on this), I don't think it is helpful to dismiss such questions without letting others form their own opinions.

The autor of Cornerfix states that he developed it as an alternative to the one size fits all approach of the camera and if he can do it, why can't others?

Regards

SR

The coded camera has 189 permutations to work from as the frame selector tab has three positions. The Tri-Elmar, for example makes use of this as it has one code, but three tab positions to help the camera write correct EXIF data and for it to apply the appropriate corrections to the file for corner colour and vignetting correction.

No camera writes truly 'raw' data to file. All 'raw' picture data is processed to some degree by every camera. When IR/lens detection is enabled and used with a coded lens, the DNG is 'corrected'.

It's a little bit hard to see when you don't have a coded lens available, but it has become abundantly clear that coded lenses with filters are the means to optimum file quality. On the 12CV I use a filter with Cornerfix and it works extremely well, but I can bring up noise in the corners quite easily. That said, I haven't compared a 15 or 16mm lens with Cornerfix and then with coded in-camera correction so i don't know whether the coded images also lose the same amount of dynamic range so it might not be a Cornerfix issue. It's just that the in-camera correction with coded lenses do all the processing in one step (hopefully!) while when using Cornerfix the file is first processed to the regular DNG file and then again with Cornerfix. As is well known, each such processing step loses data points.

Henning