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Old May 12, 2010, 12:45 PM   #11
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That The ef 24 1.4L is a great lens if you don't mind the heft cost of ownership. But that is true for all L series lenses form canon. All canon lenses can shoot macro at either 1:2 or 1:3 if it is not macro designated.

There are pentax lenses that have similar specs. Their DA* and DA series lenses.

the canon ef-s 18-55 and the pentax dal 18-55 are pretty equal
the canon 17-45 f4L and the pentax DA 15-45 f4
the canon 24 f1.4L and 24-105 F4L there are not pentax equals, but you can get a very good sigma 30mm 1.4 for the pentax and sigm 24-70 2.8.

But with either canon or pentax. You are looking a some very expensive lenses.


But for stars a telescope I would be the best option. You may need magnafication in the 1000mm+ range, and a lens with that range is very very expensive. Even if you get a 500mm lens and add TC is will still cost quiet allot and it will make the shot a bit soft.
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Old May 12, 2010, 3:47 PM   #12
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ok got one of those Tokina 28/2.8 lenses shipped for 38 which i can use for stars too. so thats that and one of the macro parts sorted. just need a 135mm or the 70-300mm tamron. i was looking at the sigma 70-300 lense, presume wimilar to the tamron. wahts that like in relation to the tamron as many people seem to think highly of the tamron

and going to be sorting a telescope out at a later date, at the moment im only gna be taking pics like i previosuly have done. just pure wide angled shots of the whole sky. rather than zoomed in at moons etc. ill wait till i can get everything in one go for all that.

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Old May 12, 2010, 3:52 PM   #13
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the sigma and tamron are very similar, but the review say the entry level tamron just slightly better then the entry level sigma. But both are good lenses.

something like a 18-135mm would be a good walk around lens, not to extreme of a range, so the IQ will be a bit better the say a 18-250.

But the pentax with the 28mm 2.8 and a 70-300 with macro and the kit lenses is a good start.
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Old May 12, 2010, 10:29 PM   #14
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I have often thought about older Tokina lenses with the Pentax K mount. These would be fully manual lenses, but Tokina has a very good name and reputation, and some of these prices are extremely tempting.

http://shop.ebay.com/i.html?_nkw=Pen...=1&_trksid=m37
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Old May 15, 2010, 6:59 AM   #15
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just got the tamron 70-300 for 64. so thats prety good going. now just gta get some extention tubes and reversal lense. maybe one more prime lense
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Old May 15, 2010, 3:16 PM   #16
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Quote:
Originally Posted by jasonholland89 View Post
maybe one more prime lense
That's what we all say. Then a few months and 85 lenses later, it's "maybe just one more lens" again... and again... and again... and again... Just wait till you notice a Helios-44 58/2 for 15, or a Meyer Trioplan 100/2.8 for 20, or a sweet little super-sharp Tele-Takumar 200/5.6 for 25... you're doomed.
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Old May 16, 2010, 6:07 AM   #17
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well thank you very much... haha. more oney i gotta spend lol. i know what you mean tho. but i just want 2 prime manual focus only lenses that i can combine to make a cheapy dual lense macro, so one say... 100mm prime lense reversed with my 24mm etc etc. well we will see lol. at least with the older macro lenses a good one only costs 20-50 quid ish. i can get a couple a month lol
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Old May 16, 2010, 11:54 AM   #18
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If you want a field of stars, here is what you do. Pick up an old K mount 50mm f1.7 lens, mount it to your KX, set for 2 second delay with a wireless remote, focus to infinity, aim it towards the sky on a tripod on a moonless night, at iso 1600, exposure time 30 seconds, at f1.7. Repeat 10 to 20 times for 10 to 20 separate frames. (You can also lay it on the ground on a blanket, point up, but be careful not to move anything.) Also, you might have a 30 second wait between images due to dark frame subtraction - just wait.

Load images on to your pc, and down load a stacker with alignment. The 30 second exposes (20 second may be better), is right on the edge of starting a star trail, you want light points. So each of the individual exposures is designed to get enough light without recording the earth's rotation. Taking a number of them and stacking them together will essentially sum their light, again while mitigating the earth's rotation.

You might want to de-noise before stacking.

This is the simplest and least expensive method I know. A Pentax-M 50mm f1.7 should run between $50 and $80. A f2 should run about $15 to $25.

http://deepskystacker.free.fr/english/index.html
http://astro.nightskypix.com/2007/03...-software.html
http://www.astrostack.com/
http://webpages.charter.net/bbiggers..._stacking.html

I helped design a little telescope out in the Texas boondocks....

http://www.as.utexas.edu/mcdonald/het/het.html
http://www.as.utexas.edu/mcdonald/het/gallery.html
http://het.as.utexas.edu/HET/PR/factoids.htm

...
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Old May 16, 2010, 3:46 PM   #19
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ive got myself a 24mm 1.7, being more of a wide angle thats what im aplannign on using, and on my last camera (was compact tho) thats the same technique i used then. 30secs is the max you could get away with. but never tried stacking so might give that a go. ta
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Old May 23, 2010, 5:43 PM   #20
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bought 2 more lenses today lol.... will have them shortly.
anyway... moon was out earlier, thought id test the tamron's zoom out. only gns show 1 pic as im too tired to sort out the rest, but its not a bad test shot. havnt edited it at all other than crop it a tad.



ok, just did a quick contrast, brightness edit etc. kinda better. but thats it for tonight all the same



and a closer image

Last edited by jasonholland89; May 23, 2010 at 5:50 PM.
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