Which IR/UV setting?

[jmoors]

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If I'm using an IR/UV filter on a non 6-bit lens, is it worth using the M8's lens recognition + UV setting?

 

If I do, it tags files with the wrong lens (C1 reads them as f1, even though it's a 50mm/f2 cron), so am I best leaving the lens recognition off, and just selecting the M8+IR/UV profile within C1?

 

Be grateful if anyone can...errr...shed any light on the matter (sorry)...

[farnz]

If you're using UV/IR filters you should set the lens detection option to:" On + UV/IR" and leave it there.

 

The EXIF defaults to f1 if the lens is not 6-bit coded.

 

Pete.

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[hoppyman]

Also selecting lens detection for non coded lenses may cause mis-identification. There is no advantage to leaving detection on (except a couple of seconds of selection time in the menu when you mount the non-coded lens).

[lars_bergquist]

I make pictures, not EXIF files. 'UV/IR on' is not detrimental to the image quality of non-coded lenses using the filter. And I do always use the filter, on both coded and non-coded lenses, therefore lens recognition is always 'UV/IR on'. What's the gripe?

 

The old man from the Age of the Medium Yellow Filter

[hoppyman]

Lars I have noticed no difference shooting an uncoded 35 Summicron with lens detection on either. However Leica simply provides a precautionary note against doing it this way as they recorded false detections with some (unspecified) lenses in testing. Should your lens be detected as say a very wide angle type you could find the wrong correction for vignetting or cyan corners being applied. May or may not be significant.

There is no gripe, just providing information for the OP.

 

I make pictures, not EXIF files. 'UV/IR on' is not detrimental to the image quality of non-coded lenses using the filter. And I do always use the filter, on both coded and non-coded lenses, therefore lens recognition is always 'UV/IR on'. What's the gripe?

 

The old man from the Age of the Medium Yellow Filter

[ho_co]

jmoors--

I'm with Pete and Lars in regard to leaving the LENS ID + UV/IR set to ON whenever using a UV/IR-Cut filter, but Geoff is correct that it is against Leica's recommendation.

 

The camera will make no exposure or color compensations if you turn LENS ID off.

 

I think in most cases it will make its default exposure and color compensation if you set LENS ID + UV/IR to ON and it can't recognize the lens.

 

With a 50 that should make little to no visible difference. But if you've got other lenses with the 6-bit coding, you may find it easier to set the camera for LENS ID + UV/IR and just leave it.

 

Remember, the M8 was finalized and its original instruction manual written before Leica saw the need for the UV/IR Cut filters. Thus, the camera isn't optimized for a situation where it's using a filter on an uncoded lens.

[photoshutter]

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It must be Off.

[hx911]

It must be Off.

 

and why, my dear troll?

 

 

this may get more interesting than 'what oil to use in my xxxxcar / bike'

[hoppyman]

Hmm the thread my get derailed.

jmoors, just try for yourself with your particular equipment. No harm done.

 

and why, my dear troll?

 

 

this may get more interesting than 'what oil to use in my xxxxcar / bike'

[stunsworth]

I've only come across one problem using uncoded lenses with the setting left at 'on' and that is with a Voigtlander 90mm used with a Voigtlander screw to M adaptor. The camera was fooled into thinking that a wider lens was mounted - presumably due to light falling onto the sensor from the cut out on the adaptor. It happened on a couple of frames, and looked rather odd.

 

Other than that no problem, and the only uncoded lens I'm currently using on a regular basis is a 35mm Pre-ASPH Summilux

[pgk]

Leica state in the manual: "Note: When using aperture priority and manual exposure setting in conjunction with a lens without 6-bit coding, the camera’s identification function must always be turned off, to prevent malfunctions."

 

However, I'd echo stunsworth's comment in that when I use uncoded 35mm lenses I see no significant difference whether the camera's recognition is either on or off. I have never tried switching off when I use my coded 24mm but it might be worth trying sometime to see just what the difference is.

[jaapv]

The only lens I have seen reported on this foum that records when uncoded is a 90 mm one. And as it happens it records itself as a 90 mm lens....There is no reason to switch detection off.

[Guest Luis D]

If you look on the INFO screen after a shot and it displays the wrong focal length (usually says 90mm) then look the lens mount and probably will be a screw sitting across the code reader. Paint the screw cap white, and it will be blinded to the reader.

 

Quite personally, I resolved after a short time to DIY code all my lenses from 35mm and wider because the firmware correction for cyan corner drift I found much less choreful than Cornerfix, not to in any way malign that wonderful software.

[MV8]

jmoors, I have the same setup as you (M8 with uncoded 50mm f2 cron) and get same tags thru C1. I leave my the setting "on" but always apply it in C1 it doesn't recognize it, no biggie. You can apply that to all your captures at the same time, select all and add adjustment.

[sean_reid]

If I'm using an IR/UV filter on a non 6-bit lens, is it worth using the M8's lens recognition + UV setting?

 

If I do, it tags files with the wrong lens (C1 reads them as f1, even though it's a 50mm/f2 cron), so am I best leaving the lens recognition off, and just selecting the M8+IR/UV profile within C1?

 

Be grateful if anyone can...errr...shed any light on the matter (sorry)...

 

I'd leave it off. There will be no chance of mis-detection and even coded 50s sometimes do better with coding off.

 

Cheers,

[Guest Luis D]

I'd leave it off. There will be no chance of mis-detection and even coded 50s sometimes do better with coding off.

 

Cheers,

 

Remember to stop and push menu buttons to change from detection-ON to -OFF or the reverse each time you change from coded to uncoded lens? I imagine it would depend how/what you shoot whether that is practical or no. I and everyone else I know who has a mixture of coded and uncoded lenses keeps permanently On+UV/IR and has no complains.

[lars_bergquist]

Leica state in the manual: "Note: When using aperture priority and manual exposure setting in conjunction with a lens without 6-bit coding, the camera’s identification function must always be turned off, to prevent malfunctions."

 

However, I'd echo stunsworth's comment in that when I use uncoded 35mm lenses I see no significant difference whether the camera's recognition is either on or off. I have never tried switching off when I use my coded 24mm but it might be worth trying sometime to see just what the difference is.

 

I agree fully. Leica simply want to keep their collective legal ass covered for all eventualities. U.S. lawyers are headhunters, but German lawyers are cannibals. Not even garlic can keep them away.

 

The old man from the New Guinea Highlands