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Messages - tryit

#1
I was very surprised that the 5D III did not have auto iso with EC.

Setting ISO seems to be a throwback to days of film, where ISO change needed replacement of the film. The Av, Tv & ISO "triangle" is now much more flexible, ISO is of equal rank in the equation as it can be changed instantly, precisely and automatically.

I take very varied shots. generally using Av mode. Generally "slow" shots are OK, but if something unexpected happens it can be missed or turn out blurry through motion blur. Auto ISO seems like a solution, but the idea of no adjustment seems crazy.

In general I think I know (in priority order)
1/ the DOF I want hence the Av. At least roughly.
2/ I know the speed I need - or at least that it should be no less than the numerical focal length ( e.g 1/200 for a 200mm lens).
3/ I know if the meter is going to be roughly right or will need compensation.
4/ with all that the iso can be set as near 100 as will work

I guess what I really want is an auto mode that reflects these priorities so I set ideal Av (optionally Tv) and EC and shoot. An algorithm would adjust ISO, perhaps up the Tv from the lens minimum and perhaps alter Av a bit if the iso was looking a bit extreme.
#2
I haven't tried ML yet. I am interested in how ML works - my 5D can produce 50fps video, can ML (even if theoretically) better that either for video or slit-scan (or other mode?) or is 50fps a limitation of the sensor? I note some p+s cameras do boast very high frame rates, but quality and number of pixels is apparently much reduced.

It looks like Interframe or Twixtor just interpolate between existing frames - you cannot add information, this would be the same as (or similar to)  stretching the image my program outputs in photoshop (bicubic interpolation).

I did have an idea that photographing via a set of mirrors parallel with the raster (so the same long thin image is repeated on the sensor)  you could take more than one line of pixels off each video frame. Should be an improvement, but I suspect rather marginal and a lot of effort.

Although I was delighted with the image I posted (it was my first attempt!) clearly it would be improved with a faster framerate. Photofinish cameras obviously have fast "frame" rates, but are presumably rather specialist bits of kit and I hoped to get what I could from my existing equipment.

Does slow slit scan in ML use the full sensor width/resolution or is it just full HD video size. Is slit-scan on the 5D iii release?
#3
Can you tell me all about ML and slit-scan images?

I created my own slit-scan software, but have since heard ML can do this.

Knowing nothing about ML or details of camera internal operation - how does ML do slit-scan - can ML change how info is obtained from the sensor? e.g. can slit (or frame) be read more than 50 FPS?

I use a canon 5D MkIII.

My program converts any .mov file (from any camera) to a slit-scan image with some controls on slit position, scanning etc.  The main limitation is the camera's FPS rate which I would dearly love to be much greater than 50FPS.

I don't really know how normal camera video mode works, but it seems that there is a non interlaced raster scan that takes 1/50 of a second (or 25 or 24), and each pixel must be exposed for some fraction of this time(?) as there is a lot of motion blur (can this be controlled?) on a frame of a moving image and a vertical moving horizontal line is sheared (becomes angled).

See www.slitcam.com where you can download and try the program - let me know what you think.



Thanks!