Re: DOF calculator

Ku

thanks, got it all now.


regards

Don from Down Under
"Kulvinder Singh Matharu" <real-address-in-sig@xxxxxxxxxxx> wrote in message
news:57tnk1t0vj4kmt1m6c14i7a1t9727kv39r@xxxxxxxxxx
> On Tue, 11 Oct 2005 02:38:30 GMT, "ArcadiaBlue"
> <mackie.don@xxxxxxxxxxx> wrote:
>
> Hi again.
>
> [snip]
>>questions. When using the calculator with my 20 D I assume I put in the
>>adjusted lens focal length? ie for my 50mm I put in 80 mm due to the
>>multiplier?
>
> No. Did you see my post in the Digital ng?
> See the DOF help file and look at "Digital Camera Considerations" at
> the following link:
> http://home.comcast.net/~jonsachs/DOF.htm
>
>>As to the resolution, assuming I wish to print generally at A4 size and
>>given the size of the 20D's CCD what resolution in lines/mm should I use.
>
> see above, but I guess that you have some leeway on the acceptable
> "in focus" quality.
>
>>I read the help file but am a little slow on these types of things and got
>>confused with my circle of confusion and the cameras.
>
> OK.
>
> The focal length is the real focal length regardless of film/sensor
> size. From the help file:
>
> Since CCDs are typically smaller than the 24x36mm frame size for
> 35mm cameras, digital cameras normally use shorter focal length
> lenses than 35mm cameras. Make sure you enter the actual camera
> focal length of your digital camera lens and not the "equivalent
> 35mm focal length".
>
> Then on the resolution:
>
> To compute the theoretical maximum resolution of your digital
> camera, you need to know the dimensions of its CCD's active area
> in mm. The resolving power of the camera in lines per mm.
> (assuming optics are not a limiting factor) is one half of the
> width of the CCD in pixels divided by the width of the CCD in mm.
> For example, if the CCD has an active area of 16x24mm and the
> camera captures 1600x2400 pixels over this area, the pixel
> density is 100 pixels/mm and the resolving power is 50 lines/mm
> (since it take 2 pixels to resolve a line).
>
> I'm not sure what your camera CCD size is but I'm sure that you can
> find that out!
>
> Good luck!
>
> --
> Kulvinder Singh Matharu
> Website : www.metalvortex.com
> Contact : www.metalvortex.com/form/form.htm
>
> "It ain't Coca Cola, it's rice", Straight to Hell - The Clash


.

Relevant Pages

  • Re: Astro CCDs still dragging their pixel feet
    ... > Compared to consumer digital cameras, ... > CCD Sensor: High Sensitvity Sony® ... > camera would be a disaster. ... Smaller pixels = less photons gathered per pixel... ...
    (sci.astro.amateur)
  • Re: digital video cam compatable?
    ... Cheapy cameras shoot 16:9 by remapping the CCD, ... Those pixels have been sat on by an elephant. ... It is better to keep the aspect ratio camera native. ... big enough to afford not using the sides when shooting 4:3. ...
    (uk.comp.sys.mac)
  • Re: OK OK Digital Cant do it.. yet.
    ... with a bit of research I figure a digital camera or line scanner can't reproduce this image because the recording speed is too slow. ... With a digital line scanner you would need to record all pixels in parallel at the same instant to prevent distortion. ...
    (rec.photo.digital)
  • Re: How many pixels?
    ... This assumes that the camera is parfocal with the oculars (which can ... on the CCD. ... It will not increase the number of resolved elements ... 1000x1000 elements or pixels is accurately imaged onto a CCD ...
    (sci.techniques.microscopy)
  • Re: Compulsory low-energy light-bulbs
    ... Brand new 60W incandescent - the camera thought it was either just right ... year old 11W CFL with maybe 2min warmup, ... And I'm limited to the CFA on the CCD. ... averaging all the red pixels, the green pixels, and the blue pixels. ...
    (uk.legal)