Re: Always wondered why they supplied a viewfinder cover...
On 13/11/2013 5:14 PM, Darren Addy wrote: On Wed, Nov 13, 2013 at 5:04 PM, Matthew Hunt wrote: Only the effect on metering, not on light reflecting onto sensor during long exposures. You know, I 've been trying to picture how that even happens. I can understand how light from the viewfinder might affect the exposure. After all the mirror is still down while metering, right? So if your eye isn't at the viewfinder, it is possible that it could be bouncing around in there and affect the meter. But this problem? The mirror is UP, during the exposure. So that implies that the mirror does not fully cover the screen on the bottom of the pentaprism. Light, coming from the viewfinder (crack between the mirror and the screen???) must reflect off the back lens element (or goes through the lens reflects off the dark filter and comes back at the sensor?). That's the only thing that I can picture. If someone has an alternative explanation, I'm all ears. The light seal between mirror and screen is never perfect, and of course on long exposures we tend to not be covering the viewfinder with our eye, so more light gets in through the finder anyway. I have also seen camera where the mirror sags a bit on long exposures and allows even more light to pass. Once stray light is in the mirror box, some is going to find it's way to the sensor. bill -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Wed, Nov 13, 2013 at 6:14 PM, Darren Addy wrote: > But this problem? The mirror is UP, during the exposure. So that > implies that the mirror does not fully cover the screen on the bottom > of the pentaprism. Light, coming from the viewfinder (crack between > the mirror and the screen???) must reflect off the back lens element > (or goes through the lens reflects off the dark filter and comes back > at the sensor?). That's the only thing that I can picture. If someone > has an alternative explanation, I'm all ears. Yeah, there's gaps around the mirror. If you take the lens off and fire a long exposure, and hold a flashlight to the viewfinder, you can see quite a bit of light getting past the edges of the mirror (at least on the K-5 II). The biggest streak of light was at the bottom of the photograph, which would correspond to the top edge of the sensor (due to the inverted image). I would guess that comes from light getting past the mirror along the back edge (closest to the sensor) and hitting the sensor pretty directly. Control of scattered light is a pretty big factor in things like telescope design. Since you're getting into astrophotography, keep an eye on your screwheads! -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Wed, Nov 13, 2013 at 5:04 PM, Matthew Hunt wrote: > Only the effect on metering, not on light reflecting onto sensor > during long exposures. You know, I 've been trying to picture how that even happens. I can understand how light from the viewfinder might affect the exposure. After all the mirror is still down while metering, right? So if your eye isn't at the viewfinder, it is possible that it could be bouncing around in there and affect the meter. But this problem? The mirror is UP, during the exposure. So that implies that the mirror does not fully cover the screen on the bottom of the pentaprism. Light, coming from the viewfinder (crack between the mirror and the screen???) must reflect off the back lens element (or goes through the lens reflects off the dark filter and comes back at the sensor?). That's the only thing that I can picture. If someone has an alternative explanation, I'm all ears. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Wed, Nov 13, 2013 at 5:33 PM, John wrote: > I think that's actually in the manual. Only the effect on metering, not on light reflecting onto sensor during long exposures. >> http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On 11/12/2013 7:10 AM, Mark Roberts wrote: Bill wrote: On 11/11/2013 5:14 PM, Darren Addy wrote: ...and now I know... http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html Sigh. Will we ever call Pentax "Pentax again? Or are we forever stuck with nimrods and the cutesy Pentax Hoya Ricoh? FFS, we get that Pentax is now a brand name, not a separate entity. And guess what? For the ones of us with a lick of brains, we don't care. Did Nikon shooters get their panties in a bunch when Nikon was bought by Mitsubishi in the 1970's? Did Mitsubishi put their name on Nikon cameras? -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
I think that's actually in the manual. On 11/11/2013 6:14 PM, Darren Addy wrote: ...and now I know... http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Tue, Nov 12, 2013 at 7:10 AM, Mark Roberts wrote: > Bill wrote: > >>On 11/11/2013 5:14 PM, Darren Addy wrote: >>> ...and now I know... >>> http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html >>> >>Sigh. >>Will we ever call Pentax "Pentax again? Or are we forever stuck with >>nimrods and the cutesy >>Pentax Hoya Ricoh? >> >>FFS, we get that Pentax is now a brand name, not a separate entity. And >>guess what? For the ones of us with a lick of brains, we don't care. > > Did Nikon shooters get their panties in a bunch when Nikon was bought > by Mitsubishi in the 1970's? What, i did not get that memo Dave > > -- > Mark Roberts - Photography & Multimedia > www.robertstech.com > > > > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Documenting Life in Rural Ontario. www.caughtinmotion.com http://brooksinthecountry.blogspot.com/ York Region, Ontario, Canada -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
> another sniveling internet fuckhead with the brains of a small rutabaga. You make Shakespeare look illiterate. B > On 12 Nov 2013, at 13:24, Bill wrote: > >> On 12/11/2013 6:10 AM, Mark Roberts wrote: >> >> >> Did Nikon shooters get their panties in a bunch when Nikon was bought >> by Mitsubishi in the 1970's? >> >> > No. When I pointed out on another forum that Nikon was just a Mitsubishi > brand name, I was given a really long lecture about Mitsubishi's "Keiretsu", > and how Nikon isn't "owned" by anyone other than Nikon. I suspect it was a > Nikon fan boy, or it may have just been a pompous piece of shit. They are > hard to tell one from the other. > The link that Darren gave was interesting up to the point where the guy > crossed out Pentax and Hoya and at that point I wrote him off as another > sniveling internet fuckhead with the brains of a small rutabaga. Pity, he may > have had something smart to say and spoiled it by coming across like a > retarded root vegetable. > > bill > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
MARK!!! Cheers, frank Walt wrote: > >Well, I can see where he's coming from. Like everyone else, my >creativity is fueled by the intimate knowledge of corporate structures. > >-- Walt “Analysis kills spontaneity.” -- Henri-Frederic Amiel -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On 11/12/2013 7:24 AM, Bill wrote: On 12/11/2013 6:10 AM, Mark Roberts wrote: Did Nikon shooters get their panties in a bunch when Nikon was bought by Mitsubishi in the 1970's? No. When I pointed out on another forum that Nikon was just a Mitsubishi brand name, I was given a really long lecture about Mitsubishi's "Keiretsu", and how Nikon isn't "owned" by anyone other than Nikon. I suspect it was a Nikon fan boy, or it may have just been a pompous piece of shit. They are hard to tell one from the other. The link that Darren gave was interesting up to the point where the guy crossed out Pentax and Hoya and at that point I wrote him off as another sniveling internet fuckhead with the brains of a small rutabaga. Pity, he may have had something smart to say and spoiled it by coming across like a retarded root vegetable. bill Well, I can see where he's coming from. Like everyone else, my creativity is fueled by the intimate knowledge of corporate structures. -- Walt -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
> From: Bill > > On 12/11/2013 6:10 AM, Mark Roberts wrote: > >> >> Did Nikon shooters get their panties in a bunch when Nikon was bought >> by Mitsubishi in the 1970's? >> >> > No. When I pointed out on another forum that Nikon was just a Mitsubishi > brand name, I was given a really long lecture about Mitsubishi's > "Keiretsu", and how Nikon isn't "owned" by anyone other than Nikon. I > suspect it was a Nikon fan boy, or it may have just been a pompous piece > of shit. They are hard to tell one from the other. > The link that Darren gave was interesting up to the point where the guy > crossed out Pentax and Hoya and at that point I wrote him off as another > sniveling internet fuckhead with the brains of a small rutabaga. Pity, > he may have had something smart to say and spoiled it by coming across > like a retarded root vegetable. > > bill Unfortunately I think you're wrong on that Bill. I did the research, and if I can believe what I read, Nikon is not just another Mitsubishi brand name, as Pentax is for Ricoh. Nikon is part of the Mitsubishi Group "Keiretsu" and member companies own shares of each others stock and therefore have a mutual interest in one another's well-being. Nikon is an independent corporation in that it's shares continue to be publicly traded and it reports independent financial results separate from all other members of the group. If it were struggling member companies of the group could decide what to do. It has it's own executives and board of directors. History we all know: That 's far different from Asahi Optical (Pentax) ceasing to exist as a corporation in 2008. When Hoya wanted to unload the Pentax camera business in 2011, it created the subsidiary Pentax Imaging Corporation. Ricoh bought all shares of that temporary entity and the combined companies were called Pentax Ricoh Imaging Company. In 2013 it simply became Ricoh Imaging with Pentax as a brand. Hoya also continues to use the Pentax name for the parts of the business it did not sell to Ricoh, mainly the medical division. Does that mean anything? It depends what one wishes to extrapolate. What it says to me (and I believe you) is that Asahi Optical had a long history of making bad decisions. That made it it vulnerable and at risk. It led to it finally be acquired and becoming non-existent as a corporate business entity. That of course is different than saying you can't purchase a new Pentax camera. Tom C. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On 12/11/2013 7:48 AM, Matthew Hunt wrote: On Tue, Nov 12, 2013 at 8:24 AM, Bill wrote: The link that Darren gave was interesting up to the point where the guy crossed out Pentax and Hoya and at that point I wrote him off as another sniveling internet fuckhead with the brains of a small rutabaga. Pity, he may have had something smart to say and spoiled it by coming across like a retarded root vegetable. Coming from you, I will take that as a compliment. Nice to see you are a glass half full kind of guy. bill -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Tue, Nov 12, 2013 at 8:24 AM, Bill wrote: > The link that Darren gave was interesting up to the point where the guy > crossed out Pentax and Hoya and at that point I wrote him off as another > sniveling internet fuckhead with the brains of a small rutabaga. Pity, he > may have had something smart to say and spoiled it by coming across like a > retarded root vegetable. Coming from you, I will take that as a compliment. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On 12/11/2013 6:10 AM, Mark Roberts wrote: Did Nikon shooters get their panties in a bunch when Nikon was bought by Mitsubishi in the 1970's? No. When I pointed out on another forum that Nikon was just a Mitsubishi brand name, I was given a really long lecture about Mitsubishi's "Keiretsu", and how Nikon isn't "owned" by anyone other than Nikon. I suspect it was a Nikon fan boy, or it may have just been a pompous piece of shit. They are hard to tell one from the other. The link that Darren gave was interesting up to the point where the guy crossed out Pentax and Hoya and at that point I wrote him off as another sniveling internet fuckhead with the brains of a small rutabaga. Pity, he may have had something smart to say and spoiled it by coming across like a retarded root vegetable. bill -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
Bill wrote: >On 11/11/2013 5:14 PM, Darren Addy wrote: >> ...and now I know... >> http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html >> >Sigh. >Will we ever call Pentax "Pentax again? Or are we forever stuck with >nimrods and the cutesy >Pentax Hoya Ricoh? > >FFS, we get that Pentax is now a brand name, not a separate entity. And >guess what? For the ones of us with a lick of brains, we don't care. Did Nikon shooters get their panties in a bunch when Nikon was bought by Mitsubishi in the 1970's? -- Mark Roberts - Photography & Multimedia www.robertstech.com -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Mon, Nov 11, 2013 at 10:09 PM, Bill wrote: > FFS, we get that Pentax is now a brand name, not a separate entity. And > guess what? For the ones of us with a lick of brains, we don't care. Sure sounds like you do. -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On 11/11/2013 5:14 PM, Darren Addy wrote: ...and now I know... http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html Sigh. Will we ever call Pentax "Pentax again? Or are we forever stuck with nimrods and the cutesy Pentax Hoya Ricoh? FFS, we get that Pentax is now a brand name, not a separate entity. And guess what? For the ones of us with a lick of brains, we don't care. bill -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Mon, Nov 11, 2013 at 7:15 PM, Stan Halpin wrote: >> ...and now I know... >> http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html > I have a very slow cranky web connection tonight so I haven't linked to your > video. Don't worry! As someone whose home Internet connection is bandwidth-limited (if no longer slow and cranky since upgrading from satellite to LTE), it's not a video, just a blog post. Signed, The Author of the Link -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
The author of the link was getting light intrusion during very long exposures (1000x ND filters, and IR filters) when the cap was off. It wasn't about metering. On Mon, Nov 11, 2013 at 7:15 PM, Stan Halpin wrote: > > On Nov 11, 2013, at 6:14 PM, Darren Addy wrote: > >> ...and now I know... >> http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html >> > > I have a very slow cranky web connection tonight so I haven't linked to your > video. But the reason to use a viewfinder cover is that light coming through > the viewfinder can/will affect the light meter reading of scene brightness. > If you have the camera on a tripod (with your eye presumably not tight > against the viewfinder) and AE turned on and nothing blocking the viewfinder, > then you'll get a false reading, particularly in a situation with light > coming from behind you. Not a problem is you use manual exposure. > > stan > > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- David Parsons Photography http://www.davidparsonsphoto.com Aloha Photographer Photoblog http://alohaphotog.blogspot.com/ -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
On Nov 11, 2013, at 6:14 PM, Darren Addy wrote: > ...and now I know... > http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html > I have a very slow cranky web connection tonight so I haven't linked to your video. But the reason to use a viewfinder cover is that light coming through the viewfinder can/will affect the light meter reading of scene brightness. If you have the camera on a tripod (with your eye presumably not tight against the viewfinder) and AE turned on and nothing blocking the viewfinder, then you'll get a false reading, particularly in a situation with light coming from behind you. Not a problem is you use manual exposure. stan -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
Re: Always wondered why they supplied a viewfinder cover...
never had this problem Dave On Mon, Nov 11, 2013 at 6:14 PM, Darren Addy wrote: > ...and now I know... > http://scotchtape.ductwhisky.com/2013/11/pentax-k-5-ii-and-strong-filters.html > > -- > Nothing is sure but death and Pentaxes. > > -- > PDML Pentax-Discuss Mail List > PDML@pdml.net > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and follow > the directions. -- Documenting Life in Rural Ontario. www.caughtinmotion.com http://brooksinthecountry.blogspot.com/ York Region, Ontario, Canada -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
