pico Posted May 16, 2018 Share #21 Posted May 16, 2018 (edited) Advertisement (gone after registration) I just discovered this nice little article about IR photography. Worth a 5 minute read. https://photofocus.com/2018/05/14/tech-corner-infra-red-filtration-for-digital-cameras/ It is worth a one-minute read for historical inaccuracy. Who are these people who write such stuff? Edited May 16, 2018 by pico 1 Quote Link to post Share on other sites More sharing options...
Advertisement Posted May 16, 2018 Posted May 16, 2018 Hi pico, Take a look here INFRARED-Image-Thread. I'm sure you'll find what you were looking for!
Leica Guy Posted May 16, 2018 Share #22 Posted May 16, 2018 It is worth a one-minute read for historical inaccuracy. Who are these people who write such stuff? And your point? Do you have a better reference you can link us too. I was simply trying to bring a little more understanding beyond put a filter on and now you have an IR image. Please add to the content of the IR discussion if you are knowledgeable on the topic. 5 Quote Link to post Share on other sites More sharing options...
uffehagen Posted May 16, 2018 Share #23 Posted May 16, 2018 I'm waiting to get my filter. Should have arrived yesterday, but it didn't. I have one question though. How do you decide which shutter speed to use? I seem to remember from earlier (Nikon gear) that the build in lightmeter is not reliable. Do you guys use Q's build in meter, or is it a trial an error approach ? 1 Quote Link to post Share on other sites More sharing options...
Leica Guy Posted May 16, 2018 Share #24 Posted May 16, 2018 (edited) I certainly am not the authority of IR photography, but I’ve had fun and a little success so far. I ended up setting the aperture at f/4 or sometimes f/8. I was concerned about focus so I wanted a reasonable DOF. I set ISO to 800. Then I let the camera pick the shutter speed and I bracketed by a stop on each side. In post I selected the image which I liked the exposure best. It seemed to work for me. You must use a tripod as exposures are in my case 10-20 secs. Hope this helps you. I did use the built in meter. Edited May 16, 2018 by Infiniumguy 3 Quote Link to post Share on other sites More sharing options...
Martin B Posted May 16, 2018 Share #25 Posted May 16, 2018 (edited) Came across this interesting thread, but I am not owning a digital Leica camera. The OP did not limit the posting just to Leica Q based systems for IR, so I just add two of my Leica based photos below even it might not fully fit in this context regarding the digital Q. I am doing and teaching IR photography since > 7 years. For digital IR, I am still using my converted Canon 5D MkII camera with 715 nm cutoff filter. Leica M6, Ilford SFX200 infrared film with 720 nm cutoff filter, home-developed in Xtol Edited May 16, 2018 by Martin B 4 Quote Link to post Share on other sites More sharing options...
Martin B Posted May 16, 2018 Share #26 Posted May 16, 2018 I certainly am not the authority of IR photography, but I’ve had fun and a little success so far. I ended up setting the aperture at f/4 or sometimes f/8. I was concerned about focus so I wanted a reasonable DOF. I set ISO to 800. Then I let the camera pick the shutter speed and I bracketed by a stop on each side. In post I selected the image which I liked the exposure best. It seemed to work for me. You must use a tripod as exposures are in my case 10-20 secs. Hope this helps you. I did use the built in meter. Not sure how it is with the internal meter in the Q camera, but in all cameras (analog and digital) which I have the needed exposure time with added IR filter is often too long to be displayed with the internal meter (it works if it is just a few seconds, but longer is then always "B"). With a IR-converted camera the exposure time is similar to regular light photography since no IR-blocking layer on top of the sensor hinders the IR light to pass through the IR light filter. But the attached filter method on top of a lens always requires much longer exposure times both on analog and digital cameras. Also be aware that by using very long exposure times > 10 seconds, some regular light will also sneak in and can potentially mess up the otherwise clear IR image (you will see more greyish dull looking images instead). The newer the digital camera, as rule of thumb the stronger the IR-blocking layer on the sensor glass cover is which will require very long exposure times as you mentioned. To determine if a digital camera can be used with the attached IR-filter method, simply hold any kind of remote control with the front directly against the camera with lens and IR filter. If the B&W image after PP displays a fully white IR diode which you won't be able to see with your eyes of course then the attached filter method works. If the dot is only grey and quite dim, you will face issues with longer exposure times needed and regular light hitting the sensor during the longer exposure. Keep in mind that the longer wave length of IR light allows you to obtain a longer depth of field (DoF) at wider open apertures compared to regular light. Approximately a f/11 aperture translates into a f/8 aperture in IR to achieve the same DoF - this means you can shoot one stop faster in IR to obtain the same DoF as in the same color photo. Avoid apertures smaller than f/11 in IR - it can lead to some unwanted hot spots which are nearly impossible to remove in PP. Some lenses are better than others to avoid hot spots - there are a few tables out there which describe which lenses work well and which won't in IR. Unfortunately M lenses are not well described how well they perform. 6 Quote Link to post Share on other sites More sharing options...
bags27 Posted May 16, 2018 Share #27 Posted May 16, 2018 Advertisement (gone after registration) Thanks so much for all this, Martin. I particularly learned from this statement of yours, which had never occurred to me: Keep in mind that the longer wave length of IR light allows you to obtain a longer depth of field (DoF) at wider open apertures compared to regular light. Approximately a f/11 aperture translates into a f/8 aperture in IR to achieve the same DoF - this means you can shoot one stop faster in IR to obtain the same DoF as in the same color photo. I think a couple of your other points, as they apply to the Q, could be met if you looked at our early IR photos, before this thread was established, starting perhaps here: https://www.l-camera-forum.com/topic/269530-leica-q-the-image-thread/page-273 Your instructor's eye and criticisms would be most welcomed! 2 Quote Link to post Share on other sites More sharing options...
Leica Guy Posted May 16, 2018 Share #28 Posted May 16, 2018 Ditto for Martin. I learned several new tidbits from your comments. Thanks much!!! 1 Quote Link to post Share on other sites More sharing options...
Astropap Posted May 17, 2018 Share #29 Posted May 17, 2018 Hmmm. Looking at some of the very cool shots in this thread has got me thinking about investing in an IR filter for the Q. I've started to read some articles about it. Very tempted to pull the trigger on the Hoya filter . . . Quote Link to post Share on other sites More sharing options...
RK+Q Posted May 17, 2018 Author Share #30 Posted May 17, 2018 Thank you Martin for sharing your experience.I always use manual Focus and move my settings between ISO 200-400, f8 and f11, the exposure I correct +1 or +1.3.Here´s something new from me.Salon Weirauch 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! 8 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/284529-infrared-image-thread/?do=findComment&comment=3520410'>More sharing options...
RK+Q Posted May 17, 2018 Author Share #31 Posted May 17, 2018 Sculpture(exceptionally wide open) 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! 13 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/284529-infrared-image-thread/?do=findComment&comment=3520413'>More sharing options...
farnz Posted May 18, 2018 Share #32 Posted May 18, 2018 . There are some infrared threads over in the M8 subforum; the M8 had a weak IR-blocking filter over the sensor, which could be exploited for infrared photography. Adding an IR-pass (visible light blocking) filter to the lens and using the rangefinder/viewfinder to compose becomes straight forward because you're not viewing the scene through the lens and (black) IR filter. I've enjoyed doing handheld digital infrared photography for more than 10 years with my M8, a 21/2.8 Kobalux lens and a 093 IR filter. The Kobalux has no IR hot spot whereas many other lenses do (under IR radiation the centre of the picture will be more exposed than the outsides). This is not simply vignetting, it's much more profound and difficult to adjust in post processing owing to the typically large difference in exposure values between the centre and the outsides. An example taken handheld in Zingst with the M8, 21/2.8 Kobalux, and 093 IR filter. Pete. 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! 17 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/284529-infrared-image-thread/?do=findComment&comment=3520621'>More sharing options...
zampelis Posted May 19, 2018 Share #33 Posted May 19, 2018 8 Quote Link to post Share on other sites More sharing options...
zampelis Posted May 19, 2018 Share #34 Posted May 19, 2018 8 Quote Link to post Share on other sites More sharing options...
Leica Guy Posted May 20, 2018 Share #35 Posted May 20, 2018 Very, very nice composition. 5 Quote Link to post Share on other sites More sharing options...
gbealnz Posted May 20, 2018 Share #36 Posted May 20, 2018 They're wonderful Zamp, but I wonder if the images are showing a "hot-spot"?Gary Quote Link to post Share on other sites More sharing options...
bags27 Posted May 20, 2018 Share #37 Posted May 20, 2018 (edited) 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! Edited May 20, 2018 by bags27 5 Quote Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/284529-infrared-image-thread/?do=findComment&comment=3521780'>More sharing options...
zampelis Posted May 20, 2018 Share #38 Posted May 20, 2018 (edited) Very, very nice composition. Thank you very much for the kind words Dan! They're wonderful Zamp, but I wonder if the images are showing a "hot-spot"?Gary Hello GB, thank you for your kind words! I am not sure yet if this is considered a hot spot. It seems that the areas that contain foliage and are hit by direct sunlight emit more of the IR light. On channel reversal it seems that intense IR is pink and regular light is blue? Not sure yet still experimenting! It may be just a nasty artefact!!! The next shot is a vertical panorama consist of three shots. I would expect to see three hot spots if it was a "middle of lens" artefact but I see only two areas in pink. The area in the middle for example shows no IR indication, (as it should be). Also the area on the left and the right of the water stream was covered with algae. But at the same time I can see that the foliage at the bottom has not a uniform pink colour even though the light was even. The thing is that even if you get this effect due to hot areas of intense IR I think it is a nice effect and I believe that it would be time well spend to find out how to manipulate this "hot spot" in order to take it to your advantage if it is not always in the middle of the lens!! Edited May 20, 2018 by zampelis Quote Link to post Share on other sites More sharing options...
zampelis Posted May 20, 2018 Share #39 Posted May 20, 2018 7 Quote Link to post Share on other sites More sharing options...
zampelis Posted May 20, 2018 Share #40 Posted May 20, 2018 6 Quote Link to post Share on other sites More sharing options...
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