Re: [APML]M51 (was [APML] M101)

[Larry McManus <lmcmanus@clearpointadv.com>]

Thanks for the info Mike


on 5/15/02 8:30 PM, Michael Cole at mrcole@earthlink.net wrote:

> Larry,
> You could open a full can of worms with questions like that <g>.  Everyone has
> there opinion as to what is best.
> I know that I went from SCT to refractors years back for film use.  I
> previously
> had a 10" SCT and it worked very good for CCD.  There is always the question
> of
> how much the central obstruction takes away from the image, but the work of
> Tony
> and Rob, Phillip, Adam Block and numerous others show that the extra focal
> length
> of reflectors can markedly increase the resolution for both film and CCD.  I
> would have a tendency to compare like focal length instruments as opposed to
> refractors with reflectors.  I think that a common mistake of anyone starting
> out
> is to accept short exposures of either film or CCD as adequate.  The longer
> the
> exposure (be it all adding them together) the better the final image.
> Good Luck,
> Mike
> 
> Larry McManus wrote:
> 
>> Mike
>> I'm new to this. I look at all the good images coming out of this group and
>> see a lot being taken with refractors. I have an 8" sct and am trying to
>> determin what to expect from images I will take by comparing pictures taken
>> by like equipment. What criteria do I use whn comparing images taken by
>> reflectors or by refractors? For instance is an 8" reflector comparable with
>> a 5" or 4" refractor?
>> Thanks...Larry
>> ----------
>>> From: Michael Cole <mrcole@earthlink.net>
>>> To: astro-photo@seds.org
>>> Subject: Re:[APML]M51 (was [APML] M101)
>>> Date: Wed, May 15, 2002, 3:31 PM
>>> 
>> 
>>> Larry,
>>> I use a six inch refractor.
>>> Mike
>>> 
>>> Larry McManus wrote:
>>> 
>>>> Very Nice...What size scope?...Larry
>>>> 
>>>> on 5/15/02 11:24 AM, Michael Cole at mrcole@earthlink.net wrote:
>>>> 
>>>>> Tony,
>>>>> You big scope guys and mosaics are taking away all the advantages of our
>>>>> little refractors.  You and Rob inspired me to try M51 with CCD (my
>>>>> third CCD picture).   Here is my attempt.  Total of over six hours
>>>>> imaging time.
>>>>> http://home.earthlink.net/~fct150/m51.htm
>>>>> 
>>>>> Tony Hallas wrote:
>>>>> 
>>>>>> Part 1.1    Type: Plain Text (text/plain)
>>>>>> Encoding: quoted-printable
>>>>> 
>>>>> --
>>>>> Michael Cole
>>>>> Urban Imager Website:
>>>>> http://home.earthlink.net/~urbanimager
>>>>> 
>>>>> 
>>>>> 
>>>>> 
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>>> --
>>> Michael Cole
>>> Urban Imager Website:
>>> http://home.earthlink.net/~urbanimager
>>> 
>>> 
>>> 
>>> 
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>> 
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> 
> --
> Michael Cole
> Urban Imager Website:
> http://home.earthlink.net/~urbanimager
> 
> 
> 
> 
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