nfotis

Yeah, the only practical reason to buy an R body for people with lots of good L glass like me is to get it with the EF lens adapter. Not for the R lenses. I still hope that Canon will release an 6D Mk3, as (probably) the final full frame dSLR for me. But until my 6D and 80D give up the ghost, I don't expect much to change (these days, I shoot more photos with my phone, I have to admit). Especially for astrophotography, I see no point spending money on non cooled cameras without a suitable form factor. I *may* buy the Astromechanics adapter for EF lenses, though. N.F.

In general, the rule of thumb is "approximately 65-70 percent of new price", if it's a current production item. For older models not anymore in production, it's supply and demand. I guess that people don't want to pay 2/3rds the price of new for small scopes like a Skymax 102. Except if these are hard to find and popular, then the used price may approach the price when sold new. Putting an OBO in your ad permits you to gauge any interest on your items. Also, you can check other places, like CN classifieds, Ebay, etc. to get an idea. N.F.

For astrophotography, Canon has brought out a special version of their mirrorless cameras (Canon EOS Ra), which has a suitable filter instead of the regular one. Myself, I think that I would use one of the ZWO/QHY/Touptek IMX571 cameras instead, more useful with scopes, cooled etc. There are EF lenses aplenty, so the mirrorless Canon can use these existing lenses via various official adapters. Personally, I think that my next upgrade will me a 6D mk2 (or mk3, if it ever gets the light of day), because I love the long battery duration and fast AF on my 6D and 80D cameras. And if I want live view, I have this too at the press of a button. And the new R lenses are painfully pricey! N.F.

In general, planetary imaging requires LOTS of focal distance, so catadioptric scopes such as SCTs and Maks have an advantage. Even at 1050mm focal distance the Esprit 150 cannot fill the frame of the 462 with Venus. If I remember correctly, this sensor has ideal sampling around f/15 to f/20, so a 2x Barlow should be fine. You could even push it to 3x for planetary imaging. Check with the field of view calculator here (Imaging Mode, then select your target, your scope and camera etc) N.F.

If I remember correctly, for Jupiter I was recording approximately 60s, for Saturn 70 sec (but with raised gain)? Used the IR cut filter in front of the ASI462MC. For Jupiter, I had two shots with the 2x Barlow (I copy settings from the SharpCap text files): Gain=300 Exposure=0.015812 (that gives approx. 64 FPS) and Gain=250 Exposure=0.022661 (approx. 44 FPS) For Saturn I had: Gain=400 (hence the grain) Exposure=0.022661 (rather underexposed) and Gain=400 Exposure=0.018 Now, the moon is almost in front of Jupiter and Saturn (and there are some clouds), so I shall wait a few nights before I venture to the rooftop again. I have also a C9.25, so I'll try to shoot with it and compare results (the biggest difference should be with Saturn, since f/20 is letting many more photons per millisecond than f/30) N.F.

Guiding means rather infrequent exposures, not at all like in planetary imaging. If you plan to use the ASI290 as a planetary camera too, USB3 is quite useful in order to keep high frame rates. N.F.

(Another idea, go full hog and buy a RASA 8" 🙂 ) N.F.

The recent version of HEQ5 accepts both types of dovetails. If you have an older version (like me), there are various options: https://www.telescope.com/catalog/product.jsp?productId=132366 https://www.firstlightoptics.com/sky-watcher-mount-accessories/adm-dual-saddle-upgrade-for-heq5-neq6-avx-zeq-ioptron.html and other variations between these two extremees N.F.

It's all done with mirrors (and not smoke 🙂 ) . The RC design is supposedly better for astrophotography , and you can add a 0.67 CDDT reducer for higher speed, as an intermediate between the Edge 8" (which can work nicely at its native focal length when hunting galaxies with the ASI533) - I am not sure that FLO offers it, though: https://www.teleskop-express.de/shop/product_info.php/language/en/info/p4955_Astro-Physics-0-67x-Focal-Reducer-for-astrophotography.html The 6" RC would be nearly as fast as a refractor. Another extreme idea would be to buy the Hyperstar for the Edge 8", to get an ultra-fast astrophotography scope, at f/2, but it seems that FLO doesn't carry this 😞 The Astromechanics adapter is quite useful, I dare say, if you have alot of Canon EF lenses (I am tempted to order one, if I settle on a camera first). You may want to check their site (I think that you want the M42 version, which supports up to APS-C sensors like the IMX571 on the ASI2600): https://www.astromechanics.org/ascom.html N.F.

Another idea would be to enter the Ritchey-Cretien world, with imaging-focused reflectors? https://www.firstlightoptics.com/telescopes-in-stock/stellalyra-6-f9-m-crf-ritchey-chrtien-telescope-ota.html Focusing EF lenses doesn't have to be coarse. There's the Astromechanics adapter for this job: https://www.firstlightoptics.com/adapters/astromechanics-ascom-aps-c-m42-to-canon-lens-controller-mark-ii.html N.F.

Supposedly the Lacerta wedges are quite good, but I haven't tested any as I don't own a refractor yet. In hot climates like in Greece, I think that investing on a 2" wedge would be prudent, but it seems that it eats too much backfocus... This might be a problem with binoviewers too. N.F.

The IMX571 is an amazing sensor, judging from the views and reports I have seen. And because it has the same pixel pitch as the 533, you can crop to an equivalent square format easily. It seems that not only ZWO and QHY offer IMX571 sensors, but other companies as well (Altair/Touptek/Rising cam is one design available, and I wouldn't be surprised to see more soon) N.F.

Some people use a sunshade, like this https://teleskopy.pl/product_info.php?cPath=32_64&products_id=3373&lunety=Os ona s oneczna Baader przelot 2 cale D ok 51 mm Another way is to wear a black t-shirt over your head and the camera, in order to be able to open your irises and be able to look better. Or, like the old time photographers looking through the looking glass, you can use a dark cloth focusing cover: https://www.aliexpress.com/i/10000001075867.html N.F.

If I am not mistaken, you use a dSLR? When focusing manually, you should be able to zoom while focusing in the back screen using "live view". A 5x zoom should help in focusing on the brightest star in your shot (or even 10x) N.F.

That punchline got me laughing hard - I am sure that you speak from personal experience 🙂 N.F.

In my opinion, the HEQ5 is the minimum mount to get for astrophotography. If you want to do dual imaging, what's the mass you expect to load the mount? (two OTAs, cameras, filters, dual saddles etc)? Multiply this amount by 1.5x in order to budget a reasonable mount (for up to 14-15 kg, an EQ6-R type mount is quite good for long exposures) N.F.

Two more photos, this time with an ES 2x Barlow in front of the ASI462 camera, I think I recorded 3000 frames. F/30 isn't ideal, but it seems to work, somehow. Stacked in Autostakkert!3, sharpened in Registax. These are my first ever stacked photos of Jupiter and Saturn. The HEQ5 mount is not ideal, the view shakes quite a lot when manually focusing, and that makes focusing hard - an electronic focuser should be quite helpful in attaining better focus (just ordered a cheap DC focus motor for my Crayford style focuser). Used also a ZWO ADC, to reduce the atmospheric dispersion. Consider these a first effort, with so-so focusing, exposure etc. Cheers, N.F.

These are quite different models. The first one is a Newtonian reflector (around 800mm focal distance, if I remember correctly) - the sideways focuser / eyepiece is a giveaway, while the second one is a Maksutov. The Skymax 150 gives 1800mm focal distance and an f/ratio of f/12. This gives a contrasty refractor-like image on the planets and the moon. Forgot to mention, this field of view calculator will give you an idea of what to expect with the framing of planets etc: https://astronomy.tools/calculators/field_of_view/ You will probably need a zoom eyepiece - the SVBONY 7-21mm zoom is quite nice and works very well with these Maksutovs (using it with both my Skymax 127 and 180). N.F.

Two more photos, this time with an ES 2x Barlow in front of the ASI462 camera, I think I recorded 3000 frames. F/30 isn't ideal, but it seems to work, somehow. Stacked in Autostakkert!3, sharpened in Registax. These are my first ever stacked photos of Jupiter and Saturn. Used also a ZWO ADC, to reduce the atmospheric dispersion. Consider these a first effort, with so-so focusing etc.

If I remove the visual back and the Skywatcher 2" diagonal, the difference isn't that great I think. I haven't weighted both, but it didn't feel much different. And it has a proper 2" to 1.25" adapter, with brass ring (the Skywatcher one is really bad, I threw it in the garbage can). N.F.

Will see when I receive the package. If the Orion manual of the Accufocus is to be trusted, I shouldn't have any problem mounting on this GSO/TS focuser. If you look also at the product photos, it doesn't look incompatible to my eyes: https://agenaastro.com/gso-2-linear-bearing-crayford-focuser-for-scts-dual-speed.html N.F.

Some lunar images shot via the Skymax 180 nearly a week ago (first light), with an ASI462 camera. These should give an idea of its capabilities. Typical parameters: shot 3000 frames video in SharpCap, stacked in Autostakkert!3, did some Unsharp Mask in GIMP of the half-sharpened image (haven't mastered Registax yet). These were a first time effort with this scope (on a HEQ5 mount). Quite capable, but sensitive to vibrations on this mount - an electronic focuser is in order. N.F.

Some lunar images shot via the Skymax 180 a week ago (first light), with an ASI462 camera. These should give an idea of its capabilities. Typical parameters: shot 3000 frames video, stacked in Autostakkert!3, did some Unsharp Mask in GIMP of the half-sharpened image (haven't mastered Registax yet). N.F.

I know about this solution, but since I already have the monorail focuser available, why not use it (and avoid mirror shift etc)? At any rate, I ordered the motor (along other stuff), will see how it works... N.F.

Thanks for the suggestions. The idea of adding (in a future) a pulley/belt set to that same motor appeals to me. For automated focusing, I am under the impression that the ZWO EAF (the new 5V version) is adequate, and cooperates with most everything (not only ASIair), without it being too pricey. But I wanted something simpler and cheaper as a first step for accurate focusing without shaking the OTP and requiring one more USB port from a computer. N.F.