Compiled & written by Andrew Nemeth, Australia
URL:   <>
Site last updated:  Sun, 01 Oct 2023

Search the FAQ  
If you can read this then the page CSS failed to load. Most likely this is because you are using an older Version-4 browser, or else one which does not properly support modern W3C standards. Either way, please upgrade your browser to something more modern & standards compliant!

Digital Accessories & Issues


On this page I've listed many products & applications you can use with Leica digital cameras. Also included is a miscellaneous discussion about common digital-related issues, which although not Leica specific, may still be of interest to "red dot" digital shooters.

RAW Converters

JPEG is adequate for snap-shots, but you have to shoot RAW to extract the maximum quality from your digital images. Consequently this requires RAW conversion to make the images usable for editing, printing etc.

So what are your better-quality RAW converter options, which also support Leica "DNG" RAW files?…

Chromatic Aberration correction

"CA" is the colour fringing or multi-coloured blooming you see in the corners of digital images — either due to poor lens design, or because a wide-angle lens was used with a sensor only designed to receive light perpendicular to its surface. The general rule of thumb is that the wider the lens, the worse the CA.

It's because of CA that M8 development was delayed for so long, and also why Leica implemented the "6-bit" scheme for its lens-mounts. See also CA remarks by Bob Atkins and Fred Miranda. To be fair though, check out this rebuttal by Ken Rockwell.

Nevertheless, CA is such well known DSLR phenomenon that software has been specifically created to help correct it. Find below a list of some of the better options:

Noise reduction software

NR applications help reduce image grain or high-ISO digital noise in photographs. Think of them as the visual equivalent of hiss-reduction techniques used to clean sound recordings.

Using NR software can be a bit of an art. Too little and the (often expensive) software has no effect. Too much, and everything will acquire an artificial "smeared plastic" look.

Although many RAW Converters have some form of noise reduction built-in, I recommend you use one of the following for professional-quality results:

In case you are interested, check out the incredibly detailed review of over twenty NR programs by Michael Almond at: <>.

Portable Storage Devices (PSD's)

If you shoot a lot when out on location, then you either have use multiple storage cards or else bring a laptop. PSD's are a third alternative, which allow transfer of images from your card onto a self-contained hard-drive. You can then erase and reuse your card. When you get back home you mount the PSD onto your computer and copy over the files. Easy.

PSDs are compact (roughly the size of a pack of cigarettes) and are much less expensive than a laptop. The only thing Leica users should be wary of is to find units which support SD memory — a lot only support Compact Flash cards.

Altitude limitations

The hard disk drives in these things are only rated to work reliably below a certain altitude threshold, typically < 3000m. So leave the PSD at base camp if you plan on going mountaineering! BTW this limitation applies all non-military grade hard drives, even those in iPods.


For general discussion about PSD's, keep an eye on the "Digital Darkroom Forum -- Storage" forum at: < - category=Storage>.

Recovering deleted images on a card

You do an in-camera review to free up card space. So you highlight a bunch of images and hit the trash button. When the progress bar appears you realise — in horror — that some of them were actually keepers. What can you do?

Eject the card from the camera, insert it into a computer card-reader and then use any of the following applications to restore the accidentally erased images:

Is DNG truly archival?

Leica have adopted the Adobe DNG open-standard format to store camera RAW image files. The big question is: will these files be readable in ten, twenty or a hundred years time?…

Realistically — probably not. Standards always change and eventually DNG will go the way of other formats (like PCD or TGA etc.) Meanwhile, it will do until the OpenRAW Working Group create something more viable.

DNG files contain two kinds of data: (1) the unprocessed image bits captured by the sensor; (2) camera-specific EXIF fields + metadata to help interpret and de-mosaic the linear stream stored in "(1)".

Should DNG ever fall out of favour, it should be relatively straightforward to convert the image into newer formats, because everything is available in a standards-compliant way. This won't necessarily be the case for OEM proprietary formats, like (say) Leica/Panasonic ".raw" files, which may not have enough market share to bother to write converters for.

DNG not supported by some RAW Converters

Most notoriously Apple Aperture, which for years only loaded DNG files from cameras it was preconfigured to support.

Didn't this fly in the face of DNG being an open-standard format? Not really. The problem was with how the RAW converter extracted data from DNG files. Apple (and a few other converters) ignored the metadata stored in the file, which meant they had to obtain camera-specific information from their own settings. When presented with a camera not on their list, they gagged.

Frankly this is brain-dead applications programming and not an inherent failure in the DNG format! Thankfully it has become a moot point, for following the Mac OS X 10.4.10 upgrade in June 2007, Aperture now works with Leica DNG files.

Adobe DNG lossless compression?

Initial versions of the Leica DMR stored DNG RAW data uncompressed, requiring 20 MB per image. For a while I believed the newer Leica M8 wrote its DNG files with the compression flag set, resulting in only 10 MB per image.

In March 2007 it transpired that this was not correct. After a lot of reluctance Leica finally admitted that the file-space saving is achieved by down-sampling the data to 8-bit. Yes, a lot of photographers are unhappy about this, including Yours (egg-on-his-face) Truly.

General DNG Links

LCD Screen protectors

Thin pieces of transparent plastic applied directly to the surface of your camera's rear LCD, to protect it from scratches, fingerprints, nose-grease and other misadventures. IMO a Very Good Idea!


Dust Spots on the CCD

The bane of DSLR users everywhere, these show up as fuzzy spots when shooting at smaller apertures or with macro lenses.

Quoting from <…/sensorcleaning/>:

The dust isn't actually on the sensor surface. It's on the surface of a filter which is in front of the actual sensor itself. This is why dust shows up more at smaller apertures. Since the dust spots are some distance from the actual sensor pixels, a wide aperture lets in light which can "go around" the dust spot. It's a bit like using a large softbox for lighting. Shadows (and what shows up in the image is the shadow of the dust spot) are light and soft. At small apertures it's like using a small pinpoint spotlight and shadows are dark and hard edged […]

Workarounds? See the above URL for chip cleaning techniques, including one the author likes to call "Open Heart Surgery" (!)

Links to chip-cleaning products

Crop-frame chip — shorter DOF?

Mount a 35mm lens onto a 1.3x crop camera and it will have a shallower focus depth, right? No, not really. There is a lot of voodoo mathematics about this online, but Pico diGoliardi nailed it on Oct 2006:

DOF doesn't change, but the acceptable Circle of Confusion (CoC) is more pessimistic due to the greater enlargement factor.

There you go. Read it slowly to let it sink in…

Just because you crop an image doesn't mean its background will suddenly fall out of focus. What does happen is that you have to enlarge the image more to end up with a same size print. Greater enlargement = smaller acceptable CoC = narrower acceptable focus limits when taking the shot.

CF/SD card performance

I/O speed, reliability in camera or transfer to computer etc. See the (huge!) Rob Galbraith database at:


It's interesting to note that current SD cards are all significantly slower than their CF equivalents, mainly due to the 16-bit data-path of the latter. Remains to be seen if the new SD-HC ("Secure Digital High Capacity") specification will increase throughput.


Return to FAQ Home