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Triangulum constellation

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#1 Michal1

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Posted 08 July 2014 - 02:14 PM

Triangulum constellation with my two favourite naked-eye objects - M 33 galaxy and NGC 752 open cluster.
Posted Image
Pentax 6x7, 200mm SMC lens, f/5.6, 53 min, Kodak E200
High resolution (4.4 Mpix)

#2 TxStars

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Posted 08 July 2014 - 02:53 PM

Looks great.
And only one exposure of 1hr.

#3 Nightfly

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Posted 09 July 2014 - 11:57 AM

Very nice Michal. The superior optic that is the 200 SMC is showing here. Great scan too BTW.

Colors look a bit desaturated, but detail is impressive. Excellent guide as well. Thanks for sharing. Great to see new images. I should be contributing some myself soon after a long break from the hobby.

Was this from last autumn?

Jim

#4 Michal1

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Posted 09 July 2014 - 04:08 PM

Thank you both!

Nightfly, you are right about the lack of saturation. I reduced color aberration by software way. This probably also caused desaturating of star colors. The 200mm SMC lens is definitely much sharper than the Takumar version. But it seems to me color aberration is more obvious with it. I will have to experiment with focusing. Now I use the position, at which the star diameters were smallest on a B&W film. Maybe the optimal focus position is different for color images.

Yes, this one comes from the last autumn. All my images taken last year on E200 come from the same night. Not a very good one. This particular frame was surprisingly guided very well. The best of all the images taken that night. The resolution of this photo seems to be limited by low exposure rather than by lens or guiding as it is usual. In the upcoming season, I consider that I will be taking several frames of the same object and stack them. I hope I will be consistently able to achieve accurate polar alignment using the software I'm currently finishing. Theoretically, I should be able to achieve sub-arcminute precission in less than 10 minutes of time. Now I need a clear night to test my program.

Nightfly, shoot and share! I'm looking forward.

M.

#5 Nightfly

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Posted 09 July 2014 - 04:35 PM

Sounds good Michal. The difference in focus for either B&W or color film should be pretty much the same given modern optics. Of course Acros is blue sensitive and E200 is red (and blue) sensitive.

I have shot almost three rolls this past month and I need to get them processed, so all this talk of images I can assure you I have more than one exposure in the tin. Waiting is part of the experience. I love it.

Good luck on your alignment program and image stacking. Would like to see that.

NF

#6 Michal1

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Posted 11 July 2014 - 06:42 PM

I just finished the first tests of my program in the field. The results look promising. I have tested it four times. In the best case, when everything went as it should, I was able to achieve sub-arcminute precission of polar alignment in 4 minutes! In the worst case, when I struggled with bugs in the program and my personal errors caused by my sleepiness, I achieved this precission in 23 minutes.






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