Topic: about yor rebuttal (Read 8674 times)

« **on:** March 12, 2005, 08:26:16 pm »

I new that sooner rather than later someone would raise this.

The point, which it seems you recognize, is that in the real world (not the theoretical one), smaller sensors require shorter focal length lenses for the same image size, and therefore produce greater DOF.

Michael

didger · « **Reply #1 on:** March 13, 2005, 12:10:01 am »

Sheeesh!! Should we change the name to the "Luminous DOF Forum"? At least the various threads are remaining relatively polite and I sincerely (honestly, no sarcasam implied) commend Howard for apologizing for a perceived offense on one of the DOF threads.

didger · « **Reply #2 on:** March 13, 2005, 03:31:41 am »

Yeah, the improved behavior is a big relief. On one of the DOF threads Howard even responded to one of my messages with a joke that had no bite to it at all and that still has me chuckling (about french fries and unlimited DOF, DR, and resolution). Even Canon vs Nikon doesn't get anyone too excited any more, though I'm a little disappointed that a few folks still don't realize that Mac is the computer platform for intellegent adults.

Flame me fast, I'm leaving for another big Sierra shooting trip very soon.

sergio · « **Reply #3 on:** March 13, 2005, 10:28:56 am »

Quote

relatively polite

Am I being any bit impolite? If you feel so it is not my intention to do so. It´s that being this site an incredible source of knowledge and learning that I thought this inaccuracy ought to be pointed out just for the sake of precision and to avoid misconception, especially among those of us who are learning. Thank you Michael anyway for your great site. I have been a regular visitor for several years now.

Sergio

www.sergiobartelsman.com

Jonathan Wienke · « **Reply #4 on:** March 13, 2005, 11:36:06 am »

That would be totally impractical, as all of the hundreds of connections between the sensor chip and its supporting circuitry would have to be designed to flex at least as far as the sensor height, and then the sensor would still have to go exactly where the optical viewfinder focusing screen has to be during viewfinding, so it would have to move out of the way before the sensor could take its place. And then there's the problem of maintaing the critical optical alignment between sensor and lens when the sensor is moving back and forth at high speed. Flipping a mirror up and down is MUCH simpler to design and build economically and keep working reliably.

Bobtrips · « **Reply #5 on:** March 13, 2005, 11:26:28 pm »

"Ten years...twenty years?"

I'm guessing way sooner. Market pressure is going to be for smaller, lighter, less expensive cameras (and lenses).

Moving to smaller sensors requires solving noise at high ISO problems (happening) and making shallow DOF an option.

I wouldn't be surprised to see a stand-alone 'DOF controller' software solution on the market in the near future. "Pick your favorite brokeh...."

sergio · « **Reply #6 on:** March 12, 2005, 07:19:32 pm »

Michael, though I agree with you in the concepts explained in your rebuttal -its in the DOF, I believe there is an inaccuracy that might lead to establish even more a widely wrong understood concept which is that depth of field is greater in wide angle lenses that in telephoto lenses. Depth of field is only dependant of the f stop used not of the focal length. It is a matter of subject size in relation to the format size used, where increased or decreased depth field is apparent but not really true. And yes, in the conceptual frame you state this, I agree with you.

Jonathan Wienke · « **Reply #7 on:** March 12, 2005, 11:52:21 pm »

For a practical, real-world example of Michael's point regarding DOF, see this thread...

Jonathan Wienke · « **Reply #8 on:** March 13, 2005, 12:13:38 am »

It does seem to be a hot topic lately, but at least the acrimony level of the discussion seems to be trending down. Like any kidney stone, "this too, shall pass..."

Jonathan Wienke · « **Reply #9 on:** March 13, 2005, 09:25:39 am »

Happy shooting!

b2martin · « **Reply #10 on:** March 13, 2005, 11:14:06 am »

Michael, I believe it's possible to have an optical viewfinder without using mirrors or prisms in a digital camera. Remember that unlike film it's possible to move the digital sensor - this is what Minolta does to stabilize the image. I think you could move the sensor into the image path to take the picture and move it out to allow viewing the image through an optical path - no mirror prism or otherwise.

« **Reply #11 on:** March 13, 2005, 11:33:35 am »

That's a possability, but one which I would guess would be frought with enginerring issues, and which would take up a lot of space.

Michael

paullantz · « **Reply #12 on:** March 13, 2005, 11:09:10 pm »

I suspect that electronic viewfinders will end up almost everywhere and will be better than optical ones (eventually)? I think we should be prepared or expect radical change in cameras and, perhaps as important, the software that will run them. At some point, the software will analyze a scene the way we do (or in that direction) and turn it into not a two dimensional bunch of pixels but break it down into its components (Uncle Fred, the pine tree, some grass, Bob's car...). Depth of field may end up being a variable we can adjust like colour.
Ten years...twenty years?

crspe · « **Reply #13 on:** March 14, 2005, 04:19:45 pm »

What I dont get is how Mike can predict on one side that the sensor will converge on an "extreme high performance," "high ISO" "6.6x8.8mm" sensors, and yet on the other side claim that medium format will continue to have a market ...

IF these "extreme high performance" sensors had 8MP ... then medium format backs (even small ones) would be able to handle 188MP simply due to the fact that they are an immense 23x larger. Of course, they would be able to maintain the same "extreme high performance"

So ... what gives? I do not believe that anyone really needs to shoot with a 188MP camera, so what is going to keep medium format alive if we can get extreme high performance and heaps of MP without all the cost, weight and hassle of medium format?

Author Topic: about yor rebuttal (Read 8674 times)