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On 21 Jun 2005 18:04:33 -0700, "atasselli@xxxxxxxxxxx"
<atasselli@xxxxxxxxxxx> wrote:
>
>
>RichA wrote:
>> On 21 Jun 2005 00:45:12 -0700, "atasselli@xxxxxxxxxxx"
>> <atasselli@xxxxxxxxxxx> wrote:
>>
>> >How can you possibly prove what you previously posted, eh? They do (or
>> >at least did) NOT use the same multicoatings (MK67DL's are f...ing
>> >better) and baffling is quite different. Optical quality in not even
>> >comparable. Plus, when something really never cools down what do you
>> >really expect?
>> >
>> >Andrea T.
>>
>> "Never really cools down" is wrong. I've used the 7" in temps down to
>> -20 and though it does take time (2 hours) it does cool down.
>> Under more moderate observing conditions (summer) it's ready in
>> 30 minutes or less.
>
>Unfortunately it is not true. Actually, in very cold weather it doesn't
>fare too badly. It is in the norther latitudes summertime that it fares
>the worse, given its oversized primary (as big as an 8"). In fact not
>even the smallest of my maks (the 6") is ready in 30 min in these
>conditions. Larger maks (8" and above) may take the whole of the night
>(which is sure short enough) if not fan-assisted.
>
>> None of what you've said about multicoatings or baffling or optical
>> differences (which are minor) could possibly account for a major
>> difference in image contrast.
>
>It's large enough to be visible to the experienced observer. While I
>know of a large number of top imagers/observers using SCTs of various
>size I can't recall one with a 7" meade mak.
I wonder if that could be because it has an f15 focal length?
>
>>Like most, you are over-emphasizing
>> the differences for whatever reason.
>
>You're downplaying the differences for whatever reason.
Because they are small?
>
>>I have't seen a graphic
>> difference in telescope performance since the bad SCTs of the 1980s.
>> Since then, "like" scopes have all been similar in performance.
>
>Depending on what you mean by "like" it can be either true or not.
>
>Andrea T.
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