Archived posting to the Leica Users Group, 2006/06/11
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Damn! And here I always thought that closing the lens down focused the light and burned a hole....Of course what you say about the light and heat is totally logical...and Lord knows you can burn paper with a big ass magnifying glass... ;-) On 6/11/06 6:16 PM, "Walt Johnson" <walt@waltjohnson.com> wrote: > Philippe > > You burn holes in shutters at wide open apertures. so the smaller the > aperture the small the risk..BTW f16 is much smaller aperture than > f1.5...bigger number but smaller hole... ;-) > > Walt > > Philippe Orlent wrote: > >> Weren't you saying then -contrary to me- that the smaller the lens >> opening was, the higher the risk? >> If not, then I misinterpreted you from the start. >> >> >> Op 11-jun-06, om 17:56 heeft Walt Johnson het volgende geschreven: >> >>> It seems simple....light=heat....less light=less heat....f16 is less >>> light (heat) than f1.5...Voila..Elementary my Dear Philippe :-P >>> >>> Philippe Orlent wrote: >>> >>>> Damn Walt, you got me thinking and testing. >>>> Took a Summarit and burned within 1 sec a hole in a newspaper page >>>> at f 1.5. >>>> The distance was about the one to focal plane. >>>> Did it again at f 16. A smaller circle on the newspapern but no >>>> burning even at 10 secs. >>>> I also think I know why. Do you? >>>> ;-) >>>> >>>> >>>> Op 11-jun-06, om 14:56 heeft Walt Johnson het volgende geschreven: >>>> >>>>> Vick >>>>> >>>>> Simply take the lens off and outside to find the solution to your >>>>> question. Focus the sun on your arm stopped down and wide open >>>>> and prove to yourself which is more likely to burn the shutter >>>>> curtain. >>>>> >>>>> Walt >>>>> >>>>> Vick Ko wrote: >>>>> >>>>>> I am just back from a very interesting trip to Bangalore (too >>>>>> few days, but >>>>>> in a way, just enough days). Interesting to see the thread on the >>>>>> temples...hmm. >>>>>> >>>>>> I was visiting my workteam, and a bit of sightseeing. The >>>>>> camera on my trip >>>>>> was a Leica CL. >>>>>> >>>>>> One question, on one day, my workteam took me out to play >>>>>> cricket and when >>>>>> it was "team photo" time, one of the guys took our cameras >>>>>> (there were 2 of >>>>>> us), stood back and took our photos. My camera was at f16, and >>>>>> I noticed >>>>>> that he put it face up on the ground. >>>>>> I had thoughts of horror as I worried about the sun burning a >>>>>> hole into the >>>>>> shutter. I did notice that he wound the film on, so I think at >>>>>> least there >>>>>> was a chance of the sun, coming in at f16, hitting the meter. >>>>>> >>>>>> So my LUG questions: >>>>>> >>>>>> 1. can the sun at f16 burn a hole? I'm not wanting to try the >>>>>> experiment >>>>>> >>>>>> 2. can the sun at f16 hurt my CL meter? It seems fine. I >>>>>> suspect the sun >>>>>> is not at its focal point for the meter face >>>>>> >>>>>> I did notice a discoloured patch that is off to the edge of the >>>>>> shutter, 1/4 >>>>>> of the way to the edge. It doesn't look like the sun "melted" >>>>>> the rubber >>>>>> there, maybe it was there always. >>>>>> >>>>>> Thanks in advance. >>>>>> >>>>>> Regards, >>>>>> >>>>>> Vick Ko >>>>>> >>>>>> ------------------------------------------------------------------- >>>>>> -- --- >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> Leica Users Group. >>>>>> See http://leica-users.org/mailman/listinfo/lug for more information >>>>>> >>>>> >>>>> _______________________________________________ >>>>> Leica Users Group. >>>>> See http://leica-users.org/mailman/listinfo/lug for more information >>>>> >>>> >>>> >>>> _______________________________________________ >>>> Leica Users Group. >>>> See http://leica-users.org/mailman/listinfo/lug for more information >>>> >>>> >>> >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >> >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information >> >> > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information