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w7ay both manual and auto. I always use manual. No VR so that is good too.
https://www.tamron.com/global/consumer/lenses/f045/spec.html#nav
First Light with new ASI585MC Pro.
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Kevin_A both manual and auto
OK, it is the next lens to look at after getting the Rokinon 135 optimized (using the English meaning of optimize, and not ZWO's usage of that term, which is a bug fix).
Perhaps get it ready for Perseids.
I have given up on the Milky Way from here. It is towards the south, and the sky pollution there is like a Bortle 8. I can get something like "looks" like the Milky Way, but nothing like what I saw as a kid in Asia.
By the way, even the ASI585 is good for a 4.7º x 2.7º field of view with a 135mm lens -- easily frames M42 and Running Man, not to mention M31. With slightly better pixel size than an ASI6200. Problem would be the dynamic range for M42 and M31.
Chen
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Darn... just when I have started to standardize on 77mm filter thread (and step downs) as apertures for my lenses. :-).
Chen
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w7ay one thing I did notice with the cooled 585 was the amount of hot pixels at HGC. I used Unity gain 198 and it was reduced greatly but that 198 setting still seems to have a bit too little FWC for my broadband imaging and bright stars really got saturated fast at f5.6 on my 115mm triplet. I am going to test gain 150 as it seems like a good balance and the extra noise will get eliminated with more total integration. Using LGC has a normal amount of hot pixels, but HGC just goes nuts!
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w7ay I tried at 25db and that was too much. This camera is worse at HGC than my 533 and 2600 cameras. I think with this 585 camera the FWC is so small at that gain that they just light up like Christmas from current leakage…. But who knows. At unity they are easily managed.
So I prefer to use where the FWC is fairly normal maybe at 15db and I can deal with the read noise with more subs and it will allow less saturation of bright objects too. Luckily my use is on smaller dim galaxies. Narrowband with filters may prove better with higher gains or Unity.
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My cooled ASI585 arrived this morning
More ZWO cables to add to the thrash. Sigh. Their cables even looks like garbage.
Swapped in my Frankenstein M54 female to M42 female x 11mm thick spacer on the ASI585 already :-). PreciseParts says it is shipping the proper 11mm adapter ring on Apr 18.
Chen
Kevin_A I
OK, I just did a different Frankensteining... I mixed and matched end plates of the "new ZWO 54mm filter drawer" with a "new ZWO 42mm drawer." So now I have a Franken drawer with a 54mm hole, with a T2 male on the other end for the ASI585's native 11mm T2 ring.
I would still need the PreciseParts adapter when I need to use a 54mm Filter Wheel.
No clear nights in sight, according to Wunderground.
Chen
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OK, Moon uncropped (but resized) single exposure through 455mm focal length and the cooled ASI585 (0 dB gain), with ASIAIR. Through thin clouds, 1 hour before sunset, just the IDAS HEUIB. Looks clean enough with such short (10ms) exposure.
I should try the camera on the FOA60-Q (highest Strehl commercial scope :-) at 901mm focal length; should fill the frame nicely, albeit with only 60mm aperture.
Pity it is a Bayer camera, otherwise I can try it too with Solar.
Should have a clear night on Tuesday.
Chen
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Kevin_A I am going to try mine on my new Esprit when it arrives soon!
The nice thing about buying a Takahashi is you don't have to constantly "upgrade" the OTA :-). Saves money on the long run. I have yet to find any new 60-90mm scope that makes me want to open up my wallet. One of them needs to produce a chromatic spot diagram close to that from the Baby-Q (Askars are about twice the spot size, although the V series looks better).
If I could take the weight, I would get the real FSQ-106; but as it is, I can barely carry that scope without camera and filters, and that is too much of a hassle. I have set everything up so I can just plop my scoe on the mount and not even do a polar alignment.
Chen
Kevin_A I tried at 25db and that was too much.
One hour before we leave astronomical twilight, the ASI585MC-Pro at Unity gain, 180 second. 455mm-f/5.4. Already quite noisy, but workable. Just average more frames.
Cooling of the small camera is no sweat at all. 8ºC ambient, -10ºC with just 25% cooler power consumption.
Chen
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Kevin_A I
1/2 hour before leaving astronomical twilight; same settings as above. I guess the previous image included a lot of sky backgroud. This one looks more promising (M51 vs sky). The dark vignette is one of my antenna masts. Once it clears and I leave twilight, I can try some autorun in ASIAIR after refocusing.
Chen
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Kevin_A Idid my first light at unity gain and may drop down to gain 150 but I do not like dropping too much below Unity… here is just slightly less than 3 hours of 180s subs at Unity… better than my 183 for sure.
Clouds came in just a few minutes after I started an autorun. 1 hour later, my all-sky camera shows this :-)
(Hey, night time sky is also blue. Just so dark that you think it is black :-). You can see the dipper on the bottom left. North is to the left.) Daytime is about -11.7 EV on this system (ASI294MC with a Samyang fisheye), the above image is at +8.5 EV. 20 f-stops difference.
Chen
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Hoo boy, this camera is sure noisy at unity gain (180 sec at 457mm-f/4.3). (Doesn't help with the Antlia RGB robbing me of the photons.)
Stable seeing tonight. This is what I got a little earlier in the ASIAIR autofocus routine:
Notice you can actually see a pretty clean Airy disc in the 3 second exposure. ASIAIR Auto focus actually works with this kind of plate scale (and very fast too, with such a small sensor). Temperature is also not changing too much; 0.7ºC in 90 minutes. But I will soon need to refocus the FSQ.
Autoguiding is pretty clean too.
Chen