Jump to content

M8 - CA and Moire


qvsm

Recommended Posts

Advertisement (gone after registration)

I've been using an M8, 50mm Summicron Pre-ASPH with the correct IR filter I recently purchased and while practicing I've found some CA/moire in some shots. See the samples I've attached.

 

Is this normal or to be expected? After coming to Leica from Canon, I'm saddened to see these results after not experiencing them previously. Interested to hear people's remarks.

 

Additionally, I have read of M8 users being happy with IQ at ISO levels of 640+ in low light. From what I've tried so far, the IQ I've found is awful at 640 - beyond that is practically throw away. Are there techniques to get around this, or is this just how it is?

 

Overall, pretty disappointed! Any thoughts, discussion would be very much welcomed.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

Link to post
Share on other sites

x

Try another RAW converter - C1 for instance. It looks like you are using Aperture. And if you get bad results at higher ISO you are exposing to the left instead of to the right. Adjust your exposure to your image contrast and keep your diffuse highlights up against the right hand side of the histogram.

Link to post
Share on other sites

Thanks Jaapv. The attached images are screen captures from previewing the raws using Preview - straight after transferring off the SD card. I haven't done any processing on them yet. But as I mentioned, I've not come across this on previous Canon setups, so curious if its common place on the M8.

Link to post
Share on other sites

The colour artefacts are typical for some RAW converters that have problems handling the steep microcontrast of an AA-filterless sensor. -And the JPGs out of camera are ummm... not optimal :(.The exposing problems usually originate from the switch from matrix-metering to centreweighed metering.

Link to post
Share on other sites

Hello Leica in London,

I'll pipe up on your posted images if you'd like. To start, I strongly suspect that your first image (the architectural detail shot) is neither moire or Chromatic Abberation, but rather the results of zooming into an on screen image past 100% magnification. The second image (of the manhole cover) appears to be 'sensor bloom' from the specular highlights being very over exposed - and the manhole cover itself appears to be over exposed as well - Almost any digital camera is capable of flaky highlights especially if the image as a whole leans toward overexposure. The third image (with the balconies) sure looks like Moire to me! Not sure what kind of 'fix' to suggest other than to ponder that your 'clipping' appears to be a tiny detail of much larger image - would Moire such as this be that much of a detraction from the greater image as a whole? Would it even show up in a print is a question to consider.

 

Looking at the three images as a whole, it leads me to wonder whether these images you've shared were clipped from 'in camera' jpegs or were they generated from DNG's you've processed? It's only a theory I have which might explain things, but the in camera jpeg engine is supposedly dreadful in the M8 cameras.

 

Hope this helps.

 

Richard in Michigan

Link to post
Share on other sites

In other words - opening via C1 should resolve that problem then? I've not stored JPG's during shooting, just DNGs.

 

Regarding the histogram, would you mind explaining further as to how to do this during hand held shooting - not clear on what you're advising!

Link to post
Share on other sites

Advertisement (gone after registration)

Thanks for the help Richard. The attachments are crops from the DNG files - rather than the M8s JPGs. Admittedly they're JPG crops as thats the only way I could get the file size down to attach them. The tall building is exactly the same unfortunately, without scaling beyond the image's actual size.

Link to post
Share on other sites

In other words - opening via C1 should resolve that problem then? I've not stored JPG's during shooting, just DNGs.

 

Regarding the histogram, would you mind explaining further as to how to do this during hand held shooting - not clear on what you're advising!

The preview is an embedded JPG from the DNG file, so you are not looking at RAW files on a preview (not that you could, they must always be converted). So judge the shots after RAW conversion in your computer. For the histogram, just look at the camera LCD when reviewing the shot.

Link to post
Share on other sites

****WARNING****

Ola' Leica In London,

Assuming I read the Quoted Post correctly, you opened your M8 images in the program "Preview". ie: Apple's image viewing software included within OSX. IF that is true, You Must Use A Different Program For Your M8! Period. Unequivocably. I'm a Mac-o-phile from way way back, but Preview, in spite of all that it does smoothly and well-enough, doesn't handle large jpeg's well and doesn't handle Camera RAW files well either (which is what the M8's DNG's are).

I know from personal experience comparing duplicate image files opened in Preview and in Photoshop (side by side) that perfectly good looking images in Photoshop look like a "pile of poo" in Preview! :-) I hope this helps! I'm not a 'hater' of Preview - I love what it provides me and open most of the images I encounter using it, but I do so with the knowledge that it has some serious weaknesses when it comes to big jpegs and especially handling the complexities of RAW Processing. :-)

 

Richard in Michigan

 

Thanks Jaapv. The attached images are screen captures from previewing the raws using Preview - straight after transferring off the SD card. I haven't done any processing on them yet. But as I mentioned, I've not come across this on previous Canon setups, so curious if its common place on the M8.
Link to post
Share on other sites

Richard said the same I would have, LiL, though in different words. :)

 

Use a RAW converter of any stripe, not a file browser like Preview, before making any judgements about the M8 files.

 

 

And BTW--to my knowledge there's no 50/2 aspheric, so you're not THAT out-of-date. ;)

Link to post
Share on other sites

Hi Ho_Co!

I hope you mean by "though in different words" that I spoke with the utmost of clarity and intelligence sprinkled with just the right amount of humor.

 

(hint: I have a huge smile on my face as I make this post!)

Photography is Fun! Sharing images is Fun!

Helping folks (online & off) is Fun!

Sometimes all of the above are Hard Hard Hard, but we do them for Fun Reasons.

Richard in Michigan

 

 

Richard said the same I would have, LiL, though in different words.

 

Use a RAW converter of any stripe, not a file browser like Preview, before making any judgements about the M8 files.

 

 

And BTW--to my knowledge there's no 50/2 aspheric, so you're not THAT out-of-date.

Link to post
Share on other sites

Richard, I meant no offense. We both said that Preview isn't a raw processor.

 

I often find that one person makes a point in a way that makes sense to me while I don't quite get what another saying the same thing means.

 

Because I had accessed the thread about half an hour before I got to look at it, you had already posted without my knowing it. When I made my comments, there was your post saying the same thing.

 

I acknowledged your precedence before repeating the message in different words.

 

Sorry if you took my comment ill.

 

 

To return to topic: I hope we get more information from LiL. I wonder if s/he was satisfied with Preview's rendering of Canon RAWs. Does that mean the camera's low-pass filter is a lot stronger than I'd expected? Or maybe his monitor resolution just fits the Canon's resolution better than the M8's? I occasionally see Moiré on screen due to the screen resolution, but it goes away with changed magnification.

 

This is the first time I've heard of someone judging a camera's performance using an image browser, and I'm intrigued by the thought. I'm looking forward to hearing more from the thread starter.

Link to post
Share on other sites

:-) Kind, Sir - No Offense was Taken. None at all.

I was attempting to make a humorous comment which fell flat in a flaming firework of failure.

 

Like you, I also hope to hear more from the Original Poster as to their success or lack there-of in improving these image problems using a 'real' Raw Processor.

 

Quite Sincerely,

Richard in Michigan

 

Richard, I meant no offense. We both said that Preview isn't a raw processor.

 

I often find that one person makes a point in a way that makes sense to me while I don't quite get what another saying the same thing means.

 

Because I had accessed the thread about half an hour before I got to look at it, you had already posted without my knowing it. When I made my comments, there was your post saying the same thing.

 

I acknowledged your precedence before repeating the message in different words.

 

Sorry if you took my comment ill.

 

 

To return to topic: I hope we get more information from LiL. I wonder if s/he was satisfied with Preview's rendering of Canon RAWs. Does that mean the camera's low-pass filter is a lot stronger than I'd expected? Or maybe his monitor resolution just fits the Canon's resolution better than the M8's? I occasionally see Moiré on screen due to the screen resolution, but it goes away with changed magnification.

 

This is the first time I've heard of someone judging a camera's performance using an image browser, and I'm intrigued by the thought. I'm looking forward to hearing more from the thread starter.

Link to post
Share on other sites

Many thanks all for the help and advice. You'll be glad to know the advice given was spot on. I opened the above files in LR3.2 and the issues I originally raised were mostly gone. All but ever so slight moire on the tall building with balconies. I probably should have known not to use Preview, but in all honesty, having never experienced this while browsing the CD2's from my 5D via Preview, I didn't know any better.

 

I'll now have a good hunt on the forum for information on which tool to use to get the best from the M8's files.

Link to post
Share on other sites

... I probably should have known not to use Preview, but in all honesty, having never experienced this while browsing the CD2's from my 5D via Preview, I didn't know any better....

LiL, I've learned something: It's fascinating to me that it worked with the 5D files. :)

 

Since I had never tried using Preview for viewing my own stuff, it had never occurred to me that it would work for any camera.

 

We were just standing on our opposite sides of the same issue.

 

I'm glad Lightroom works better. I hope you come to like the camera. Keep us posted.

 

Thanks for the post, and for checking us out. And thanks for the education. :D

Link to post
Share on other sites

Archived

This topic is now archived and is closed to further replies.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...