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  • Hey all, just changed over the backend after 15 years I figured time to give it a bit of an update, its probably gonna be a bit weird for most of you and i am sure there is a few bugs to work out but it should kinda work the same as before... hopefully :)

Dslr Af?

Gene Crucean

Gene Crucean

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I don't own a camera company (duh) but would I be crazy in asking for an AF system that works like a DSLR camera? I would love for the scarlet to focus like my Nikon in C auto focus mode.

Is that crazy talk? Or is that the AF of the future?

Here is the 51 point AF module for the Nikon D3.
http://a.img-dpreview.com/reviews/NikonD3/Images/Additional/afmodule.jpg
 
With Canon You can actually focus by your eyes. There is a sensor that tracks the movement of Your eye and knows which area of the frame You are looking at (independent of what the camera is looking at) and then focuses on that...

Sure it will be great on Scarlet, but this would require included HQ viewfinder and tons of other electronics with price of Scarlet doubling with ease..
 
I don't know about doubling because it's going to have an autofocus system as is. Maybe the system you are talking about. How do current cameras (HVX, EX1) AF systems work internally?
 
I didn't mean it would double for normal AF. I was referring to the eye-controlled focus.

Cheap AF works on image contrast. The more advanced (and expensive) ones have dedicated chips like the one bellow. This is precisely the reason why cine cameras don't have an autofocus...

Which way RED will go? Only they know...
 
This wouldn't really work on Scarlet but on a bigger camera it would be cool to have a touch screen lcd where the "focus puller" simply touches the part of the image that should be in focus.
 
But how would You do focus-pull shots? Remember that almost all AF system bounce back and forth "overshooting" the desired focus plane before settling on it. Some do it better then others, but I don't see logic of employing "focus-puller" to control AF...
 
I don't know, how does the eye tracking thing work? Like that but with finger tracking. :)

It probably wouldn't work. Just a crazy idea.
 
What would be really nice is to turn on the autofocus, let it settle, and define focus lock point A. Then focus on something else, define focus lock point B. Then you can toggle back and forth between A&B on the fly with the transition time between the two points being programmable. Or just a dial to turn to manually transition between point A&B. I don't know, just another crazy idea. :)
 
kmikami said:
What would be really nice is to turn on the autofocus, let it settle, and define focus lock point A. Then focus on something else, define focus lock point B. Then you can toggle back and forth between A&B on the fly with the transition time between the two points being programmable. Or just a dial to turn to manually transition between point A&B. I don't know, just another crazy idea. :)
Click to expand...

I think Canon XL-H1 already has this option.
 
Joofa said:
I think Canon XL-H1 already has this option.
Click to expand...

The Sony EX1 has this as well- it's actually pretty slick. You can set focus, zoom and exposure and then soft or linear transition and time between memory point A or B. Faster and cheaper than an AC. :)

-Noah
 
I think everyone if forgetting that the Autofocus mode only works on DSLR's when the mirror is down and the focus module is in the prism.

Since light is straight to chip in video cameras, adding a focus system like that of a DSLR would require a new prism or other element affecting the clarity of the lenses in place.

Not worth it, especially in the Scarlet where we want all the light possible to hit that chip.

KO
 
knock out said:
I think everyone if forgetting that the Autofocus mode only works on DSLR's when the mirror is down and the focus module is in the prism.

Since light is straight to chip in video cameras, adding a focus system like that of a DSLR would require a new prism or other element affecting the clarity of the lenses in place.

Not worth it, especially in the Scarlet where we want all the light possible to hit that chip.

KO
Click to expand...

Ah! Very good point.
 
knock out said:
I think everyone if forgetting that the Autofocus mode only works on DSLR's when the mirror is down and the focus module is in the prism.

Since light is straight to chip in video cameras, adding a focus system like that of a DSLR would require a new prism or other element affecting the clarity of the lenses in place.

KO
Click to expand...

Don''t know what the DSLRs out there are doing, but we have successfully developed auto focus systems using certain proprietary techniques that work.
 
kmikami said:
What would be really nice is to turn on the autofocus, let it settle, and define focus lock point A. Then focus on something else, define focus lock point B. Then you can toggle back and forth between A&B on the fly with the transition time between the two points being programmable. Or just a dial to turn to manually transition between point A&B. I don't know, just another crazy idea. :)
Click to expand...

This is already implemented in the Canon XL 20x L-series lens used with XL1/XL1s/XL2 and XL-H-series cameras. You could do it for both the focus and the zoom position - just not at the same time. I use it almost always when I shoot on the XL-series... (PS: You do have to focus manually to set the end point)
 
Joofa said:
Don''t know what the DSLRs out there are doing, but we have successfully developed auto focus systems using certain proprietary techniques that work.
Click to expand...

Yeah, there are plenty of other options, such as contrast-based AF. When implemented well it can be more precise then chip-based, but that is rarely the case...
 
Joofa said:
How do chip-based do it?
Click to expand...

Unlike "contrast-based" the "chip-based" solution has the need to use a prism as KNOCK OUT correctly pointed out above. The contrast-based "only" analyses the actual image contrast of the sensor - therefore it is SW-based and as a result a little "slower". But don't nail me to the cross just yet, I did mention that this depend on the implementation and great AF is possible with "contrast-based" SW solution - which I am sure is what Your system is based on...
 
Thanks for the info Peter, I was not aware of contrast based solutions. I will need to set some time aside to learn more about those designs.

This would be a good feature for Scarlet, but unlikely due to time constraints and other more important stuff. It can't hurt to dream though!

KO
 
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