The Beginners Questions Area

The new corkscrew is mild compared to the old one. My first experience with the old one was as a passenger in Jim Herlinger's AP Corvette, on his victory lap in a regional SCCA race. I hung on tight to the roll bar as we dropped into 6A, and it was scary. I used to do track days in 911s at the new Laguna Seca, and the corner wasn't as jaw-dropping. The corner that scared me the most was the next corner, the new turn 9, at the bottom of the hill.

I agree. I have experienced only the new corkscrew and do not remember it as especially problematic. But turn nine was by far the scariest one, especially if running without electronic help.

It's hard to tell yourself to bury the throttle when you're charging down the hill to turn 9.

Are you saying photon noise isn't real? That's odd because the effects of photon noise are something I (most deep-sky visual observers, for that matter) have directly experienced many times. To cut to the chase, the reason a larger aperture telescope allows the visual detection and observation of fainter (e.g. lower surface brightness) extended deep-sky objects, is that the larger total light packet delivered to the eyepiece has a - wait for it - higher signal-to-noise ratio (SNR) than a smaller aperture scope is able to deliver when pointed at the same object. The larger aperture delivers more total light from the object (galaxy, nebula, or star cluster) to the eye. Photon noise being proportional to the square root of the total light, that larger light packet has an improved SNR. As a result, lower contrast objects and details in those objects become observable.

If you ever get the chance to attend a star party at a true dark sky site, wander the field and enjoy views through as many telescopes as possible. Don't just walk past the smaller rigs. They'll offer nice views, too. But when you step up to the eyepiece of an 18-inch or larger Dob, mentally compare the view in that scope's eyepiece with the view of the same object delivered by a 10-inch or smaller instrument. It's the increased aperture, larger light packet, and improved SNR that make all the difference.

Some of those improvements are real if you compare 35mm film with 6x9cm, provided you make the prints the same size (and not the same degree of enlargement).

Don Cox

Bob,
I could download chapter 3 [This ones's] but after trying to get more, it isn't possible:

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Any remark resp. help? - Thanks

Awesome captures Jim. It's great that you kept track of those.
I was the Gopher for the Shadow team in 72. Got to chase parts and watch them build CanAm cars. Ended up the team photographer but left all my prints and negatives with the team.

thanks for that information but isnt that so called noise just particles in the atmosphere ?

Jim made a comment that noise was no different with changing iso setting FOR THE SAME EXPOSURE his quote.. exposure= shutter+ aperture right ? so i shot a studio image setting my strobes to a different value ,so exposure isnt just shutter and aperture is it !

if they open the file all the information is there right in front of them. the problem no one thinks of opening the file, kind of like looking a a book cover and not reading whats inside.

WRT the bold part, I didn't hear anybody say that it was. I'd like to see your "quote" in context. I certainly hope that I never said exposure is shutter + aperture only. Exposure is measured in lux-seconds. Changing the lux and/or changing the seconds affects exposure.

I don't need much encouragement to post a few more. I'm not getting anything out of the rest of this thread at this point.

Jim Hall:

Dan Gurney:

Bruce at speed:

Jim at speed:

For the photon shot noise to appear, photons need to strike a detector.

Where did that "no one" come from? - you were told that you changed exposure. Could you please drop the act?

How to trigger half of the forum. 😅

I would argue that indeed, exposure is not the amount of light hitting the sensor in most technical sense. You really cannot quantify it in general, and you cannot say if it's good or bad exposure by the amount of light either. And so (tongue in cheek) most of you are wrong anyway, because you don't know proper language to describe a phenomena. How do you want to handle, discuss and teach photography if you don't know the language? (tongue in cheek).