ISOless sensors, read noise and photography - many questions!

Started Oct 3, 2013 | Discussions thread
OP boardsy Senior Member • Posts: 2,215
Re: quit trying to avoid taking credit for useful thread

RussellInCincinnati wrote:

boardsy: I'd still wonder about ""the same" or better results by post-processing an image from a camera set to ISO 800" - if the same, why bother?

Because (a) no more bracketing (b) never a blown highlight, highlights always visually top priority if you don't want your photos to look like unfinished artworks (c) simplification of always using ISO 800 when the light's bad, no matter exactly how bad it is. One less field decision that could result in a screwup if you set a real high ISO and then forgot to reset it later. Which mistake have done approximately one zillion times. (d) Am wagering if you're using a camera known to your raw processing software, the raw processing software can push the data (beyond the minimum read noise ISO such as Nex C3 ISO 800) with more computational resources and customizability than camera firmware. Am thinking here about RawTherapee working with all 64-bit numbers when extracting the last bit of highlight detail, all the work put into Lightroom etc. (e) this is getting real unimportant but it is psychologically less stressful knowing that you're using your sensor at the 4%-or-whatever-better minimum read noise setting, rather than the most-perfect-EVF-preview setting.

Ordinary interior light, quite small F-stop for perfect clarity throughout scene depth. ISO 800 didn't cut it for 1/6th second exposure, needed ISO 3200 or so. But left cam at ISO 800 and moved an exposure slider in raw post-processing software. Feels like the only low-stress, no-bracketing file clutter, infinite-highlight-detail way to fly now.

Ok, I'll take the credit for this thread! Though let it be known that I'm just riding the coat-tails of bob2n, Great Bustard et al's schooling in the recent "ISO is not part of exposure" DPR-wars, and the concomitant ISO-less approach. A big education for me, as there is plenty of misinformation out there on the mythical "exposure triangle", raising ISO "increases the light available to the sensor"(< I actually read that in a tutorial! ) etc.

And thanks again for persevering further than I did since the previous "full circle" apparent dead-end. I put this in practice yesterday evening - grabbing a few street shots in the dark, I set ISO at 800, set shutter speed at 1/50 (min. necessary for my FDn 50/1.4 + Lens Turbo hand-held) and f2 so under-exposed, and fired away without worrying about the LCD or ISO/brightness. Haven't got around to pp yet, but I'm confident about highlight preservation and brightness-raising in ACR.

Like this uninspired snap, underexposed at hand-held imits of 1/30 & f2 on FDn 35/2 + LT, base ISO, and pushed in ACR to least as bright as the scene was to the eye (could take more perhaps if desired), with highlight detail preserved:

-- hide signature --

my Flickr

Post (hide subjects) Posted by
(unknown member)
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow