Shotshell Pressure Question?

[ch]

Bruce, 1st what's an SL. When you tossed the shell in the fire was the expected result your pappy found out and had a talkin with you ch



Jack, I used to take a lot of pictures years back slr under stood it film speed f stop yahda yahda, then they made them into computers I kept shooting the slr (I don't need 1 of thoes goofy cameras) well here I am I want to put pictures on here so I go to wally world to get me one or use my daugthers what are the guidelines to get a good picture the pixles or what ever. Thanks ch

[Bill Bates]

Originally Posted by calvin humburg

Bruce,

Jack, I used to take a lot of pictures years back slr under stood it film speed f stop yahda yahda, then they made them into computers I kept shooting the slr (I don't need 1 of thoes goofy cameras) well here I am I want to put pictures on here so I go to wally world to get me one or use my daugthers what are the guidelines to get a good picture the pixles or what ever. Thanks ch

this is a bit of a wander from the OT.

The rules haven't changed when it comes to photography iso (film speed and grain), f/stop, shutter speed and such, it is still the same. If you have a good film SLR with decent lenses you may want to see if there is a digital body that will use them. Don't get to hung up on mega pixels when it comes to posting pics on the web. There isn't a current digital camera that doesn't have way more than needed when it comes to pixels. If you want to make wall size prints maybe more pixels matter and maybe not. Once we passed 3 mega pixels it just became a number for the marketing boys. The quality of pixels maybe another thing but that is a discussion for a good digital camera techno geek forum like DPReview.

Go with a digital SLR with a few decent lenses. Point and shot digitals most older film photgraphers find slow and frustrating.

[Austin W Hogan]

Jack, Mark, Drew; I think Jack's recent post frames my concerns rather precisely. Jack and Mark cite British proof of 3 1/4 and 3 1/2 Tons. If those are tons made of English pounds, and expressed as the force on English square inches, they are pressures of 6500 psi and 7000 psi. Metric tons and English square inches raise those numbers 10%. If they are metric tons and metric centimeters squared, they are about 15000 psi, comparable to SAAMI proof loads.
Measuring transient pressure, especially when the total event occurs in milliseconds, is not a precise experiment; the numbers quoted always have to be referenced to the time that the pressure is averaged and the measuring instrument.
That is the reason I prefer to choose a gentle load from a simple shot column length and shot speed. I know that a shot column 1 inch long leaving the gun at 1300 ft/sec is pretty hot irrespective of gauge; a shot column 3/4 inch long leaving at less than 1200 ft /sec is pretty mild.
I think RST tables back me up on this; 10 ga 1 1/8 ounce (.686 inch), 12 ga 7/8 ounce (.603 inch ) and 3/4 ounce (.520 inch), 16 ga 7/8 ounce (. 732 inch) and 3/4 ounce (.626 inch), 20 ga 3/4 ounce (.672 inch)and 28 gauge 5/8 ounce (.756 inch) all at less than 1200 ft/sec are without a doubt very gentle loads, and it is not necessary to quote pressure to verify this.
Incidentally, Parker, prior to the formation of the interindustry for runner of SAAMI in the 1920's, proofed by lengthening the shot column (adding more shot weight, not powder weight) according to TPS.

Best, Austin

[TARNATION !!!]

Originally Posted by calvin humburg

Jack, I used to take a lot of pictures years back slr under stood it film speed f stop yahda yahda, then they made them into computers I kept shooting the slr (I don't need 1 of thoes goofy cameras) well here I am I want to put pictures on here so I go to wally world to get me one or use my daugthers what are the guidelines to get a good picture the pixles or what ever. Thanks ch

Calvin: Bill pretty much says it all. I agree for computer purposes anything beyond the 3MP is more than needed and everthing out there is way beyond 3MP now anyway. If you mastered the SLR, all the concepts remain the same for a DSLR but you can do a bit more with the camera that might have been done later in the film processing, like enhanced color saturation. I agree fully with Bill, if you have good lenses with your film camera, try to see what you can find that will accept those lenses or see if there is an adapter that could make them fit. If you want control (f stop/shutter/iso/white balance/dof/manual focus etc), you won't want a point and shoot, although there is plenty you can do with them and they are convenient for their ease of carrying anywhere. Looking forward to seeing some pics.
Cheers,
Jack