A surprise!
Posted 05/07/2025 - 16:01
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okay, starting from a zero (or even minus!) knowledge level of astronomy photography I foolishly had a look at this (on the website I should be clear) and yes the price did make me wince slightly. Is it essentially a 200mm (or 250mm) lens with the optics optimised for distant objects? And why the focuser? Surely that far away you would focus at infinity. If the questions are too foolish I apologise and promise to stick to birds and insects in future!
Stephen
645Z, K1, K1ii, K3iii + mono, K3ii, K3,KP, K-S1, K200D,K10D, K-r, Ist* DL, Ist* D, QS-1 plus too many film bodies !
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645Z, K1, K1ii, K3iii + mono, K3ii, K3,KP, K-S1, K200D,K10D, K-r, Ist* DL, Ist* D, QS-1 plus too many film bodies !
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Posted 05/07/2025 - 16:09
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SSF1957 wrote:
If the questions are too foolish I apologise and promise to stick to birds and insects in future!
Aren't there spiders from Mars??If the questions are too foolish I apologise and promise to stick to birds and insects in future!
Steve
Posted 05/07/2025 - 17:54
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Lubbyman wrote:
Aren't there spiders from Mars??
Steve
Aren't there spiders from Mars??
Steve
Stephen
645Z, K1, K1ii, K3iii + mono, K3ii, K3,KP, K-S1, K200D,K10D, K-r, Ist* DL, Ist* D, QS-1 plus too many film bodies !
Flickr Page
Photocrowd Page
645Z, K1, K1ii, K3iii + mono, K3ii, K3,KP, K-S1, K200D,K10D, K-r, Ist* DL, Ist* D, QS-1 plus too many film bodies !
Flickr Page
Photocrowd Page
Posted 05/07/2025 - 18:40
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Lubbyman wrote:
Steve
No spiders on Mars SSF1957 wrote:
If the questions are too foolish I apologise and promise to stick to birds and insects in future!
Aren't there spiders from Mars??If the questions are too foolish I apologise and promise to stick to birds and insects in future!
Steve
But it is filling up with NASA's discarded junk
SSF1957 wrote:
okay, starting from a zero (or even minus!) knowledge level of astronomy photography I foolishly had a look at this (on the website I should be clear) and yes the price did make me wince slightly. Is it essentially a 200mm (or 250mm) lens with the optics optimised for distant objects? And why the focuser? Surely that far away you would focus at infinity. If the questions are too foolish I apologise and promise to stick to birds and insects in future!
There is a focuser because of temperature change. During a long shooting sessions (these can be upto 12hrs long), the air in the scope changes. This can, and does effect focus. I use Electronic Auto Focusers that are set to refocus every 2° of temperature change.okay, starting from a zero (or even minus!) knowledge level of astronomy photography I foolishly had a look at this (on the website I should be clear) and yes the price did make me wince slightly. Is it essentially a 200mm (or 250mm) lens with the optics optimised for distant objects? And why the focuser? Surely that far away you would focus at infinity. If the questions are too foolish I apologise and promise to stick to birds and insects in future!
Other things also have to be taken in to consideration. Such back focus, this is the distance from sensor to the rear most optics. On most it should be 55mm, but sometimes it has to be fine tuned with shims to get the back focus bang on. This then can adjust the focal point, and you'll have to refocus.
To be honest astrophotography should be classed as a dark art...
...good job it's modern times or I would be burnt at the stake for witchcraft
Or if those Roman Catholic lunatics where in charge, I believe my fate would be most horrible!
Posted 05/07/2025 - 23:43 - Helpful Comment
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The explanation is most welcome, Spad. Informative and to the point.
Thank you Stephen for asking the questions I am too ignorant to think of, but now that I know them, I feel are important to know the answers to
Rather interesting this astrophotography lark and well beyond me. I am, however, smart enough not to visit *that* website!
Thank you Stephen for asking the questions I am too ignorant to think of, but now that I know them, I feel are important to know the answers to
Rather interesting this astrophotography lark and well beyond me. I am, however, smart enough not to visit *that* website!
Nigel.
Getting older and grumpier. Taking longer to decide which lens to use today.
K5 with auto-everything lenses
A collection of manual primes to keep me in touch with the pleasures of doing it old-school.
Getting older and grumpier. Taking longer to decide which lens to use today.
K5 with auto-everything lenses
A collection of manual primes to keep me in touch with the pleasures of doing it old-school.
Posted 06/07/2025 - 18:53 - Helpful Comment
Link
Spad wrote:
To be honest astrophotography should be classed as a dark art...
Thanks for the explanation Spad - I think I will consider it a "Dark Art" and steer clear - maybe a few dark skies and stars weather permitting
To be honest astrophotography should be classed as a dark art...
Stephen
645Z, K1, K1ii, K3iii + mono, K3ii, K3,KP, K-S1, K200D,K10D, K-r, Ist* DL, Ist* D, QS-1 plus too many film bodies !
Flickr Page
Photocrowd Page
645Z, K1, K1ii, K3iii + mono, K3ii, K3,KP, K-S1, K200D,K10D, K-r, Ist* DL, Ist* D, QS-1 plus too many film bodies !
Flickr Page
Photocrowd Page
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1375 posts
18 years
Drooling over things I can't afford...
And I saw this!
Just for the record.... I can't afford either of them!