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View Full Version : Digi camera measuring lens threads?



graffian
16-09-2010, 10:17 PM
I wondered if any one had tried photographing stuff to take measurment's?
I just tried but best I could get from the pics I had taken was the image
below, I should have picked a sharper image. The initial measurement was
taken by scaling to the thread pitch, maybe I should have gone for diameter?


http://www.velocette.co.cc/velo-images/barrel-thread2.jpg

irving2008
16-09-2010, 10:44 PM
what camera did you use? its obviously struggling with the closeups... and what is the purpose/goal?

BillTodd
16-09-2010, 11:51 PM
Apparently, camera thread are commonly 55 whitworth form even if of metric diameters and pitch.

Bill

graffian
16-09-2010, 11:54 PM
what camera did you use? its obviously struggling with the closeups... and what is the purpose/goal?
Probably my fault, the camera seems quite good at macro pic's.
It's a Ricoh R6, was 60 quid at jessops so would expect it to be pretty good;-)
I often want to check thread angles and radii, as well as other
small stuff.

I don't know why I put lens in the subject, nothing to do with measuring camera
lens threads, those detaild are probably easy to get. Ah probably had lens on my mind
as I was wondering about strapping the camera to a microscope;-)

I will have to spend a bit of time and see if I can get a pic with better
definition. I can get nice a nice sharp pic but it will be a lot smaller, those pics
have the thread full width of the pic. The pic below is a cam follower, looks quite
good when it's it filling a laptop screen. The screw thread though it is focusing on either
the peaks or tha backgrounds. I also have pretty shaky hands.
http://www.velocette.co.cc/velo-images/mac-follower4s.jpg

John S
17-09-2010, 12:07 AM
The pic below is a cam follower, looks quite
good when it's it filling a laptop screen. The screw thread though it is focusing on either
the peaks or tha backgrounds. I also have pretty shaky hands.
http://www.velocette.co.cc/velo-images/mac-follower4s.jpg
http://www.velocette.co.cc/velo-images/mac-followers4s.jpg

Looks like a Velo cam follower, you can clearly see the custom lapping marks where they lapped them in on the corridor floor outside the canteen.

Many happy ? hours spent at hall Green waiting for spares

Jonathan
17-09-2010, 12:37 AM
Maybe get one of these...

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320408048052

(That's not necessarily the cheapest one, just the first I found)

I've got one and it's great for filming the milling machine as it'll stand pretty much anywhere on the machine!

John S
17-09-2010, 01:00 AM
Camera threads for tripods are 1/4" x 20 Whitworth, I just got a whit bolt, sawn the head off and held the stud on a mag stand instead of a dial gauge.

graffian
17-09-2010, 01:00 AM
That was flogged to me as being in good usable condition, I never
expected it to be good, but could see from his pics they had the original shape.
I did comment to him that they were not usable, would destroy my nice new cam,
I got a realy shitty reply asking what do you expect from old parts. I was originally going to Stellite
them but if I reground them I could have them cased. But I managed to find a set of Stellited ones.

I do have a tripod. I will try it.

Jonathan
17-09-2010, 01:17 AM
Magnetics stands are good I guess, but I always seem to find I can rarely stick it in just the right spot!

Vikash
21-10-2010, 03:23 PM
I wondered if any one had tried photographing stuff to take measurment's?
I haven't, but I would suggest at the very least to take into account barrel distortion of a lens - otherwise the measured thread angles taken from a pic might be all screwed up - pardon the pun.