Hi, I've been looking on getting a V. But.... Im not convinced on the optical quality yet. So I downloaded the spot diagrams for it, and compared against Askar 65PHQ, Askar 300pro, Askar 400, Askar 600. I combined the total um spread one by one for each, and when you compare, it looks like the attached (see attached) Basically the Askar V at similar focal length to Fra 300 is 20% to 57% more degraded, 65PHQ 33% to 46% more degraded, Askar Fra 400 8% degraded to 0.7% upgraded[b], [/b]FRA 600 - better 18 to 26% upgraded % degrade
Performance against Askar Fra 300
Askar V 60 mm 270mm f4.5 reducer use 20.82220094%
Askar V 80mm reducer 384mm f4.8 57.6649695%
% degrade Performance against Askar 65PHQ
Askar V 60mm 360mm f6 Flattener use 33.20396923%
Askar V 80mm 495 f6.18 Flattener use 46.72329251%
% degrade (%upgraded)
Performance against Askar Fra 400
Askar 80mm reducer 384mm f4.8 8.326406207%
Askar V 60mm 360mm f6 Flattener -0.736007204% % degrade %(upgraded)
Performance against Askar Fra 600
Askar V 60mm 360mm f6 Flattener -26.43723891
Askar V 80mm 495 f6.18 Flattener -18.97110442
So against the 300 you can expect, all things being equal, 20% reduction in optical quality, so on and so forth. I also cant find too many images published in astrobin and elsewhere that would refute the above. Either it is too early to compare due to lack of finished images, or the above numbers paint the picture. Any users here want to correct me that would be very much aprpeciated. This post is intended to bring out the best Askar V discussion so I can literally order one, not to discourage anyone who owns one
Performance against Askar Fra 300
Askar V 60 mm 270mm f4.5 reducer use 20.82220094%
Askar V 80mm reducer 384mm f4.8 57.6649695%
% degrade Performance against Askar 65PHQ
Askar V 60mm 360mm f6 Flattener use 33.20396923%
Askar V 80mm 495 f6.18 Flattener use 46.72329251%
% degrade (%upgraded)
Performance against Askar Fra 400
Askar 80mm reducer 384mm f4.8 8.326406207%
Askar V 60mm 360mm f6 Flattener -0.736007204% % degrade %(upgraded)
Performance against Askar Fra 600
Askar V 60mm 360mm f6 Flattener -26.43723891
Askar V 80mm 495 f6.18 Flattener -18.97110442
So against the 300 you can expect, all things being equal, 20% reduction in optical quality, so on and so forth. I also cant find too many images published in astrobin and elsewhere that would refute the above. Either it is too early to compare due to lack of finished images, or the above numbers paint the picture. Any users here want to correct me that would be very much aprpeciated. This post is intended to bring out the best Askar V discussion so I can literally order one, not to discourage anyone who owns one
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A break in the clouds and got 4.4 hours on seagull nebula. A few things... the image quality is excellent. The quality of stars both for ca and shape is almost perfect. This was using the worst performing theoretical stat's 60mm with reducer. What I noticed was the stat's are purist assuming good seeing etc etc. So almost never would you get the stat's in the field. For 4 hours I was surprised at the amount of data and clarity which comes down to the fast fl coupled with triplet clarity of optics. I had to rethink my processing because of the fine detail loss using my old pixinsight steps. A much lighter touch required as the native image was much better quality. With the 6 different fl at disposal and based of the stat's and this image this works for me nicely.
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