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Messages - Roman

#1
Hey,

Firstly please dont rip my head off if this is an idiotic idea, I dont know tooo much about audio but just had a random thought about audio and gain control. :)

People hate AGC, why?

Because it's automatically adjusting, and often not how you'd like. Once it's recorded, you've got no idea how loud it 'should' have been.

So first thing that comes to mind is turning the bloody thing off haha.

But I was thinking, what if there was a way to make the AGC aim to instantaneously normalise every volume to say 75% volume of what the mic can do... BUT the difference being that it datalogs the gain 'offset' required to get the audio to this level.

So something that would normally clip, records at 75% volume. Something that would normally be a pin dropping, records at 75% volume. So it would sound terrible, but the idea is that you post process this to use the 'offset' information to make the pin dropping super quiet again, and the clipped parts really loud again. But you never have to worry about clipping or signal:noise ratio being awful.

Here's a very poor visualisation of what I'm thinking.

First picture down is how you normally record... Volume goes up and down with recording.

Second picture down would be the "75% goal" AGC turned on.

And then third picture down would be the 75% goal AGC post processed into an 'HDR' audio file.



#2
Share Your Photos / Re: Thread photos dual iso
September 21, 2014, 09:42:51 PM
Quotewith full respect but those examples are possible to shoot with just single iso..

And how are you able to judge that? From viewing an edited photo which has the contrast hugely reduced? lol.










#3
Hey,

So in the Canon menus you can set the exposure to adjust by either 1/2 or 1/3rd of a stop per click of the dial.

However! There are a few situations where having slightly finer control over the shutter speed would be beneficial.

Panning shots with motorsport, generally I start at about 1/100th of a second exposure time and then dial it up or down to suit distance from the vehicle, vehicle speed, etc.

However the jump from 100th to the next setting up or down can be quite significant, in terms of how much motion blur is in the picture. So sometimes I wish I had finer control.

Is there an ML option to somehow temporarily set the camera to increase/decrease exposure time in 1/10th stops or similar?

Or another option, is there a good way to take 3 shots at differening exposure lengths, say 1/80th, 1/100th, 1/120th while compensating exposure or aperture to keep the same brightness as the first shot? It would be handy for dialing in initially, which shutter speed suits best.

It's probably something that can be acheived already, but I'm not sure which combination of features would allow for it.

Apologies if this is a repeat or annoying question, I've used ML extensively over the last year or two but have not seen a combination which can acheive the above.
Thanks,
#4
Share Your Photos / Re: Thread photos dual iso
September 14, 2014, 11:54:51 AM



#5
Sheesh getting carried away a bit, Why even discuss mass production, when it's not even confirmed that it's possible to work yet?
#6
Tragic Lantern / Re: Raw video on 50d and 40d
June 13, 2013, 03:15:52 PM
How old are your batteries though?

I've got 4 batteries of unknown age, and yes I must admit the 50D hoofs through them a lot quicker than my 600D doing the same thing.

However I've no clue how old they are, I'm sure a fresh set wouldnt go amiss.

In other news, my Samyang 35 F1.4 has actually got a really awesome minimum focus distance even without reversing or extension tubes.

This is a crop at minimum focus distance:

http://iforce.co.nz/i/5rgrkus5.aoh.jpg

Looking forward to trying out the 5x zoom mode at MFD and seeing what interesting or horrifying things I can capture haha.
#7
As has been said in other similar threads, most people impulse purchasing a DSLR are likely to end up with something Nikon, or something Canon with little or no tech knowledge about the differences.

So what are the motivations? With electronics there's the massive stigma that if you buy something old, you're an idiot and that's usually true.

If they go into the shop and see a 2 year old 650D or a 3 month old Nikon somethingsomething for the same money, they are going to buy what's newest on the assumption that it's better. Canon pushes out something 'new' each year in the ***D line for this reason, it would seem.

To be honest I think it's reaching a bit of a plateau in terms of what hardware features you can add to an entry level camera.

When you buy an entry level DSLR like a 700D, it's still bazillions better in terms of usability for first time shooters than it was 10 years ago.

In terms of the software innovation, which is effectively maximising the usability and effectiveness of the hardware with software - Magic Lantern has shown what each camera is easily capable of, if they chose not to ignore development in this manner.

Why in god's name no Canon DSLR has a built in intervalometer at the very least, so many years after a digital cameras have become the norm truly boggles my mind.

It seems Canon wants to treat it's DSLRs as though they are still film cameras, a mechanical item with the minimum software and firmware required to make it functional.

In saying this though it's sooooooo hard to change anything in a giant corporation, it's like trying to do a 3 point turn with an oil tanker.

If there's a "Dont fix what aint broke" mentality there, it going to change any time soon.
#8
Tragic Lantern / Re: Raw video on 50d and 40d
June 12, 2013, 06:37:37 PM
Dont think so, apart from apeture or ND filters.

Situation might get a little better if someone fishes around and finds a native 24fps mode to reduce fps from rather than 30.
#9
Tragic Lantern / Re: Raw video on 50d and 40d
June 11, 2013, 12:59:47 PM
No one knows yet.
#10
Tragic Lantern / Re: Raw video on 50d and 40d
June 11, 2013, 12:47:48 PM
Firmware.
#11
Updated 50D to new speed available - 70 to 73mb/s with the new build. Woot!
#12
Raw Video / Re: Aliasing with RAW
June 10, 2013, 10:28:19 AM
With the 5D3, is it possible that they are sampling from the entire sensor, rather than skipping?

So for example to make one pixel, they take an average from an entire area rather than skipping sections and reading from only one part.
#13
Raw Video / Re: Aliasing with RAW
June 09, 2013, 09:54:08 AM
Quote from: kgv5 on June 09, 2013, 09:04:14 AM

Maybe, but isn't a crop mode made out of 1920x1080? (I mean picture with 1x magnification, resolution say 1792 x something)

Think of it as, because the sensor is downsampling in a way that means certain parts of the sensor are skipped,  there is a gap of a certain distance between parts of the sensor it records from.

A blurs the image an exact minimal amount, so the light that would have fell apon 'the gap' reaches the parts that are recording.

When you change how much of the sensor you are using, or using the full sensor at a different resolution, the size of the gap changes so the VAF filter will either now make your image blurry (if now less of a gap) or not work as well as intended (if more of a gap)

For what we're doing with raw, generally filming at higher resolutions with the full sensor, I would expect a vaf filter to remove aliasing at the cost of the image being blurrier than you'd like.
#14
Also people are going "If we can shoot at xyz bits, we can use 10million x 8million resolution!"

Forgetting there's a certain sized resolution that's the maximum for each camera, some/most of which are already recording at the maximum available.
#15
Tragic Lantern / Re: Raw video on 50d and 40d
June 09, 2013, 09:03:10 AM
Not really, if the focus isnt changing through the shot.

It's just that the above is the quickest method.

(I have a lilliput monitor but dont use it if I can help it)
#16
Tragic Lantern / Re: Raw video on 50d and 40d
June 09, 2013, 01:38:40 AM
5x zoom only.
#17
Tragic Lantern / Re: Raw video on 50d and 40d
June 08, 2013, 10:57:02 PM
Quote from: menoc on June 08, 2013, 09:52:11 PM
I have found absolute 0 sharpess in the ML menus combined with 0 sharpness in picture style helps  . . . But I'mnot seeing that much crap like that guy is getting. He shot the worst scenerio possible!

Any sharpness settings only affect what you see on the liveview screen, being a raw file?
#18
Quote from: 3pointedit on June 08, 2013, 11:50:15 AM
Infact this is exactly how I shoot computer monitors at work. Often you find a moire effect when the screen pitch matches that of the camera resolution (a form of extreme brick wall). The easiest way to solve this is to back off focus just a little bit. But sure you get a little contamination in the blacks/edges.

Or perhaps, (if lighting allows) stop down as far as you can go, to introduce diffraction... I think that's essentially the same as what the aliasing filter does.
#19
Tragic Lantern / Re: Raw video on 50d and 40d
June 08, 2013, 01:22:05 PM
Whoa 2k shutter count! Nice. I was pretty happy with 18k, which is still quite low for a 5+ year old camera.

Quote from: dacssfreak on June 08, 2013, 11:17:57 AM
Roman, i dont get the problem with the Sticky DOF. As soon as you Enable Exp. Override it changes the Aperture right after you dialed it in. Where's your problem?

Right you are! Sorry didnt realise that's what it did, haha.
#20
Quote from: jchristman on June 07, 2013, 08:40:32 PM
I just came across this optical filter solution for moire. I'm intrigued:

http://recordingsofnature.wordpress.com/2012/12/04/cyl-filter-moire-and-aliasing-filter-for-hd-dslr-video/

Since there are lines skipped causing the aliasing, the problem is that some light reaches one pixel*, some light reaches the gap in the middle, then some light reaches the next pixel across.
So what an aliasing filter does is blur the light coming to the pixels, so the lost colour information that otherwise gets sent to the 'gap' is included.

Which obviously reduces sharpness and contrast to some extent, but the idea of the aliasing filter is to reduce it by the exact minimum amount required for sensor size and how much line skipping it's doing so it's not noticably blurry...

Could you not acheive exactly the same thing, by shifting the lense focus by a tiny amount forward or backward from a 'perfect' focus and then sharpening the image afterwards?
I know that sounds pretty blasphemous to a photography crowd to intentionally misfocus, but maybe worth experimenting with.
Or just smear some butter on the front of your lense, hahaha.

* = I realise this isnt the correct terminology, not sure what the RGBG cluster type thing is called that recieves light on the sensor.
#21
Tragic Lantern / Re: Raw video on 50d and 40d
June 08, 2013, 08:23:28 AM
Okay so I'm sure we're all totally amazed at what the 50D can do, especially since it never came with video for starters!

However, there are still a few realistic ways I think it could be better.
Since I'm not technically capable of programming Magic Lantern in any which way, I thought I'd put together a wish list for futre 50D video features, as follows...

1. A hard upper limit to exposure time, of 1/fps when raw video mode is turned on. i.e. it will not let you shift the exposure time beyond 1/24th of a second if you are shooting 24fps.

2. Tying into the above, exposure time indicated in degrees, 180, 275, etc.

3. Clarification on real exposure time, when fps override is turned on. For example, if you set the camera to 1/250th of a second when at 30fps, and then set fps override to 24fps... Is it still 1/250th? Or is it 1/250th * (30/24) ?    If it's the latter, then updating exposure time to match FPS would be handy. (And make sure the 360 degree exposure time matches fps override, instead of 30fps still)

4. Perhaps far fetched, but there was mention that there could possibly be other native video modes apart from 30fps?
Perhaps would help with the above scenario if there was a native 24fps setting floating around somewhere in the camera already.

5. Sticky DOF automatically working when you hit the record button. As it's quite cumbersome to use electronic lenses at the moment.

6. Not 50D specific, but I find it a real pain to autofocus in video mode, and usually only do it at the start of a shot. So what I tend to do, (if not manually focus0 is turn liveview off, autofocus the camera the 'normal' way, (as this works very quickly) and then switch it back to liveview and go from there. Would it be possible to automate this sequence? Live view off > autofocus > focus confirmation > liveview on? Assuming anyone else would find that handy of course. If that could be automated to a half shutter press or something, it would be freaken sweet.

So just a few thoughts, anyone else got any other (realistic) suggestions?
#22
Tragic Lantern / Re: Raw video on 50d and 40d
June 07, 2013, 08:05:08 AM
50D Live view only works in certain camera modes - make sure you've got it set to 'M' on the dial.


#23
Tragic Lantern / Re: Raw video on 50d and 40d
June 06, 2013, 06:08:52 PM
Once the raw video mode is enabled, you can close out of the window and press the live view button. Then press it again to start recording, press it again to stop.
#24
Does the indicated buffer change, depending on settings? As I get the 30+25 for 600D and that's it.
#25
Ahh great stuff! Thanks.

600D buffer is 30+25

And 50D is 27+27+27+27+27+27   (27x6)