On dark frame subtraction.

2010-09-13 Thread Boris Liberman
Hi! Reading the discussion between Ralf and others regarding the type of night shooting that Ralf excels in, and idea occurred to me. Please have a look: http://pentax-ways.blogspot.com/2010/09/on-dark-frame-subtraction.html What would you say? Thanks. Boris -- PDML Pentax-Discuss Mail

Re: On dark frame subtraction.

2010-09-13 Thread Miserere
On 13 September 2010 04:13, Boris Liberman wrote: > Hi! > > Reading the discussion between Ralf and others regarding the type of night > shooting that Ralf excels in, and idea occurred to me. > > Please have a look: > > http://pentax-ways.blogspot.com/2010/09/on-dark-frame-subtraction.html > > Wha

Re: On dark frame subtraction.

2010-09-13 Thread Boris Liberman
On 9/13/2010 1:15 PM, Miserere wrote: This is what astronomers do on ground and space-based telescopes. The issue with cameras is that the dark frame needs to be the same exposure length as the image you take; for your system to work one would take a 1/2 hour exposure (say) and the camera would f

Re: On dark frame subtraction.

2010-09-13 Thread Mark Roberts
Miserere wrote: >Or...Pentax could just make DFS optional so those who want to turn it >off and do DFS with software of the computer can do so, and those who >don't know what the hell DFS is (or don't care) will leave the camera >on the default "DFS: ON". > >For what it's worth, even a camera like

Re: On dark frame subtraction.

2010-09-13 Thread Matthew Hunt
On Mon, Sep 13, 2010 at 8:07 AM, Boris Liberman wrote: > Right. The particular DFS frame may depend on the outside temperature. So > yes, for perfect DFS, the procedure will have to be done every night. But > only once for the night. It actually depends more on the sensor temperature than the ou

Re: On dark frame subtraction.

2010-09-13 Thread Steven Desjardins
If nothing else it appears you can turn off the NR. On Mon, Sep 13, 2010 at 8:36 AM, Mark Roberts wrote: > Miserere wrote: > >>Or...Pentax could just make DFS optional so those who want to turn it >>off and do DFS with software of the computer can do so, and those who >>don't know what the hell D

Re: On dark frame subtraction.

2010-09-13 Thread Miserere
But can you do it for long exposures? That's the issue here. --M. On 13/09/2010, Steven Desjardins wrote: > If nothing else it appears you can turn off the NR. > > On Mon, Sep 13, 2010 at 8:36 AM, Mark Roberts wrote: >> Miserere wrote: >> >>>Or...Pentax could just make DFS optional so those who

Re: On dark frame subtraction.

2010-09-13 Thread Mark Roberts
Miserere wrote: >On 13/09/2010, Steven Desjardins wrote: >> >> On Mon, Sep 13, 2010 at 8:36 AM, Mark Roberts wrote: >>> Miserere wrote: >>> Or...Pentax could just make DFS optional so those who want to turn it off and do DFS with software of the computer can do so, and those who don'

Re: On dark frame subtraction.

2010-09-13 Thread mike wilson
Boris Liberman wrote: Hi! Reading the discussion between Ralf and others regarding the type of night shooting that Ralf excels in, and idea occurred to me. Please have a look: http://pentax-ways.blogspot.com/2010/09/on-dark-frame-subtraction.html What would you say? I would say that Pent

Re: On dark frame subtraction.

2010-09-13 Thread Godfrey DiGiorgi
I'd keep using film for ultra-long night exposures. Although reciprocity effects tend to do the same thing ... On Mon, Sep 13, 2010 at 12:47 PM, mike wilson wrote: > Boris Liberman wrote: > >> Hi! >> >> Reading the discussion between Ralf and others regarding the type of night >> shooting that Ra

Re: On dark frame subtraction.

2010-09-13 Thread P. J. Alling
On 9/13/2010 3:47 PM, mike wilson wrote: Boris Liberman wrote: Hi! Reading the discussion between Ralf and others regarding the type of night shooting that Ralf excels in, and idea occurred to me. Please have a look: http://pentax-ways.blogspot.com/2010/09/on-dark-frame-subtraction.html

Re: On dark frame subtraction.

2010-09-13 Thread Ralf R. Radermacher
Miserere wrote: > ...so there's no reason for Pentax not to implement it. No more, that is. With the K20D and the K-7 they obviously had very good reasons not to let us see just how inferior their sorry excuse of a Samsung sensor really is. It could be switched off in all Pentax DSLRs with Sony

Re: On dark frame subtraction.

2010-09-13 Thread mike wilson
P. J. Alling wrote: On 9/13/2010 3:47 PM, mike wilson wrote: Boris Liberman wrote: Hi! Reading the discussion between Ralf and others regarding the type of night shooting that Ralf excels in, and idea occurred to me. Please have a look: http://pentax-ways.blogspot.com/2010/09/on-dark-f

Re: On dark frame subtraction.

2010-09-13 Thread Bob Sullivan
Ralf, You ought to sell the K-7 now and get your money out of it. It sounds useless to you. Regards, Bob S. 2010/9/13 Ralf R. Radermacher : > Miserere wrote: > >> ...so there's no reason for Pentax not to implement it. > > No more, that is. With the K20D and the K-7 they obviously had very good

Re: On dark frame subtraction.

2010-09-13 Thread Boris Liberman
On 9/13/2010 9:47 PM, mike wilson wrote: I would say that Pentax wants you to buy a second body I am not sure about Ralf, but I've enough bodies. /("Pentax" deliberately omitted from the previous sentence :-) )/ They are: * film: MZ-6 * digital: K10D and K-7 * compact: Optio W30 (as a c