Expose properly with a DSLR

I have long time followed exactly the histogram of the DSLR to expose so that as much of the dynamic range is covered. However, that is not ideal in all cases.

In most cases shadow detail is what is lacking and the picture looks very dark and even unpleasant sometimes. Video codec, aliasing, lack of resolution etc. makes things even worse. This occurs mostly when shooting at available light outside and sun is pointing somewhat towards the camera (or some other light source doing the same). Even when it is not directly pointing to the camera, the areas on front of it will be very easily dark. Sun is extremely powerful light source and competing with it with exposure can be tricky.

People usually shoot with flat picture profiles, which a little bit helps on this case too. However, flat picture styles will reduce the available dynamic range because it compresses it. You will get more shadow details because the blacks are moved to right in the histogram, but the image quality reduces.

I found an old article which recommended exposing towards the right side (towards highlights) of the histogram. I could not believe it because I was thinking that I will lose dynamic range if I do that. I made an experiment: I shot an evening scene which was exposed as dark as it was naturally to the eye. Looks like the right way to do it? Yeah right. I took another shot which I overexposed it so that the histogram was leaning to the right (highlight side) so that everything was too light still without clipping the highlights.

As expected from my experiment: the scene that I made to look like it was in reality looked like it was in reality. Fiddling with Aperture – there was some noise and I could not get much more shadow detail out of it than there was. It was like it was exposed to look like it was and that’s it. No further alterations very much possible.

Ok now I then went to the next picture which was overexposed and a bit too bright. It looked like a failure to begin with. However, after I adjusted the exposure in Aperture, it started looking like it looked to the eye in the evening. And guess what – it had less noise – with same ISO setting! I could find lots of shadow detail in the picture.

I was recently also looking my old video scenes that I have shot for example in North Cape. In general they are rather muddy and dark. Some have rather unpleasant look. I have been trying to adjust them with Color and then with these couple of free plugins for FCPX but if I bring up the blacks, block artifacts and noise start to show up rather severely and the video quality drops to almost to a level of SD. In middle of these scenes there was one overexposed scene. And voila, when I exposed it in post processing towards blacks, there was lots of shadow detail, and even highlight detail in the scene and no visible noise.

So what I do now when I shoot next time (this is still an experiment, so don’t ruin your footage based on this instruction, or if you do, do it with your own risk):- I use a bit less flat picture style than e.g. Technicolor because the picture style after all is not a holy grail and does not fix all the problems in the exposure there are because the file format is not 12 bit RAW. Neutral picture style with contrast reduction is fine. Another possibility is to use Technicolor Cinestyle profile with contrast setting in the middle (not dialed all the way down). – Then I expose a bit towards highlights but make sure the highlights do not clip (otherwise the image quality will be low because highlights are clipped).

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Automotive grade LiFePo battery cells and automotive grade brushless DC electric motor power controllers

In addition to the RC batteries from http://www.hobbyking.com, you can also get more robust packaged batteries from for example here:

http://www.ev-power.eu/

They also have high power motor controllers which are at or exceeding power class of a big hybrid aircraft.

How to use Nokia N9 as music production tool – encoding your sequencer’s tracks with Dolby Headphone using the Nokia N9

Nokia N9 has Dolby Headphone effect, which is gives pretty neat effect – makes the sound being perceived to be less inside the head. I have tried with several tracks that it can be helpful sometimes and I could even use that in my music. However, I don’t have Dolby Headphone encoder in my Logic Studio (as far as I know). However, if you want to spend the time, you can use N9 for the task and here is how:

1. Record your (stereo) audio track in your audio sequencer (like Logic, Cubase, whatever). Add a loud beep or loud peaky drum sample to the beginning of the track.
2. Mount the N9 to your computer. Then copy the track to N9. I have not tried wav files, if these don’t get indexed, you may have to do a detour and encode the file to lossless flac format.
2. Go to Settings application -> Applications -> Music. Turn on the switch Dolby Headphone.
3. Connect your computer audio input to the headphone output of your N9 (assuming you have the cable)
4. Start recording on sequencer (another stereo track) and go to Music player on N9, locate your track and play back the sound.
5. Now cut the track so that it starts from the loud peak in the beginning.
6. Line up the original track and the track you just recorded visually – the peaks should align exactly with each other.
7. Now you can cut the synchronization sound from your track and mute the original track and you have a track with Dolby Headphone encoding on it.

This roundtrip will add noise of course because it goes through analog domain (DA->analog head phone amp->analog input->AD-conversion) and it will also otherwise reduce the quality slightly. However, many synthesizers I use have only analog outputs and it does not prevent me to use them and I have never had trouble with noise. The added noise may be negligible.

This is not the fastest way to do Dolby Headphone encoding for your audio track in your sequencer probably and certainly is not the official way, but this is a neat effect that you can do with the built-in software of your N9 and is kinda awesome feature. And I think the quality of the audio output in the N9 is so good that I could consider using this myself like I explained above.

I have been using this kind of syncing with a peaking signal in DSLR movie making (where I have recorded the sound separately with a audio recorder (I have Zoom H4N for that)) and it works because unlike in the prehistoric times when you could not sync two tracks if they were from separate machines (as there was speed variation, e.g. if you had two drum machines from same manufacturer, set both to 120 bpm and then record both separately and then try to line up the tracks, it started going out of sync in mere seconds if these were not midi synced with each other), but with modern equipment this is not a problem. The tracks will line up nicely.

N9 Software Update with MacOSX or Linux (part 1)

This has been available for some time, but in case you have not noticed it, the new software release really worths installing as it significantly improves the performance of the device. You can see that for example the scrolling smoothness will be improved after updating from. Latest software release for Nokia N9 via Nokia page is 20.2011.40-4.

You can get a Mac and Linux flasher from here:http://tablets-dev.nokia.com/maemo-dev-env-downloads.php

The flash image is not currently available outside Nokia but is inside the exe that you can download from the Nokia web site for updating the N9. Unfortunately this exe obviously only runs on Windows (I for example don’t have any Windows machines around and for me the Windows exe is completely useless).

If someone manages to extract the flash image from the exe, it can be in theory flashed with Mac and Linux flashers. If you manage to succeed with that, please let me know and I will mention about it on my blog. Please write me at karoliina dot t dot salminen at gmail dot com or write to the comments on this post (please note that the comments are moderated to avoid spam and it will take time for me to approve them, so don’t be afraid if you don’t see them appearing immediately).

I tried to send a question about this to Nokia customer care [about how can I update my N9 with my Mac] but I was unable to do so because the form required all the lengthy numbers like serial number and my personal N9 was not with me today so I could not check it.

UPDATE: Got information that there indeed is a beta version (unstable) Mac Nokia Updater out there. http://betalabs.nokia.com/apps/nokia-software-updater-for-macIt does not state that it would support Nokia N9. I downloaded it and tried it with my N9. It didn’t work, it stated that N9 is not supported.

Also people have been using a software called navifirm to extract the flash image out of the Nokia software updater exe to enable flashing it using Mac. However, according to my Googling this software also runs on Windows, so it may not be so straightforward for Mac users to use that route. Maybe the beta version of the software updater for Mac is the best bet at the moment in case it would start supporting N9 (that I hope but don’t know).

It seems I still don’t have a solution for this. If you know a working solution how to get N9 flashed with Mac, please let me know.If I will find a solution for this, I will post a new blog post with instructions how to do it with Mac.

External link: Article about Flying wings

If you are into flying wings like me, this PowerPoint slideset might interest you. It compares the basics of conventional airliner and flying wing airliner.Much bigger planes in other words, than my interest area. However, some of the pros and cons findings for each configuration also apply for the small version. Not all though as the starting point does not have engine nacelles and engines sticking out of the wing. http://www.engbrasil.eng.br/index_arquivos/ap23.pdfI haven’t done yet comparison for the wetted area of a flying wing compared to a sailplane like structure.Logic tells that the flying wing in this size category might have more wetted area. But I am not sure. I need to design both and then measure the wetted area of both and compare.I am not a big fan of wing twist and the amount of wing twist on PUL-10 causes me shivers (wing tip twisted 10 degrees). That can’t be good for cruise, simply can not. Ten degrees is insane amount of twist – on cruise the tips are on negative angle of attack and cause a lots of negative lift. The wing tips act as rather poor tails this way – it is very short coupled and if you have tail deflected that much on that close, the wing center section will need to lift also the negative lift of the tips which will make the plane to perform poorer. I am quite sure that a flying wing should be made stable without that much twist.I have a related idea for a flying wing:- one problem with flying wing is that flaps can not be used- what if you had small trim tails that look like the ones in SpaceShipOne. When flaps would be down, the trim tail, would cause opposing pitching moment to negate the pitching moment of the flap- The elevator control otherwise would be like on a flying wing, with elevons.- I haven’t tried this out yet but it can be tested with RC model.

Short note: Electric motors for hybrid or electric aircraft

The Joby Motors seems to have good enough KV-values for running slow turning props (especially JM2S and JM2):
http://www.jobymotors.com/public/views/pages/products.php

Electric Lazair uses these motors.Standard windings are available for up to 700 volt system!

Video: Burt Rutan: Bipod update. Oshkosh Airventure 2011

HD-link: http://youtu.be/HSwkY5M4pPo?hd=1