Long Exposure | Forum profile

I didn't know the d40 had a meter. I took auto iso off and selected 200- the same iso in my pentax. Histogram? I don't understand digital, and I don't think I ever will. But if i did use the d40 meter, would the image significantly differ from that of the pentax? I mean exposure-wise.

Yes the d40 definitely has a meter, which you can set to meter in spot, center weighted (which is probably what your Pentax uses) or matrix (which calculates the exposure based on light levels of the entire scene). If you meter the same scene at the same focal length (remember the sensor of the d40 is smaller than a 35mm negative so 18mm on the d40 would be about 28mm on film) with the iso, shutter speed, and aperture constant I would expect...

If you don't have or don't trust meters. Or if it is just way too dark to get useable results [*] -- here are good rule-of-thump recommendations. Applies for film & digital. Does not consider film specific reciprocity failure (see MFG's website) www.fredparker.com/ultexp1.htm#Light Intensity Chart [*] look at the fineprint -- often meters (dSLR, or otherwise) will not accurately measure below 0EV, some go down to -2EV....

thanks, this is interesting: maybe this two common sense definitions found with Google could be related to (1) the typical longest exposure time (1/60) you can use hand-held with the normal 50mm lens, and (2) the typical exposure time (1s) at which, historically, you need to apply some compensation for reciprocity failure..

Gedankenexperiment No, I meant it literally. Googling around I see two definitions that say "more than 1/60th" and "more than half a second". I guess there's no right answer but for the sake of simplicity I would go with 'longer than 1 second'. But it's not my group.

@Ottoman42: if i use f/22, what is the longest time of exposure can it produce? can i get a picture that is not blown-out during broad daylight with an exposure beyond 1 minute?

@Lucas The longer the shutter is open the more light gets in. an F Stop of 11 just wasn’t a high enough setting to avoid over exposing your image try an F/22 next time.