nfotis

On 18/04/2023 at 09:20, The Admiral said:

Ignore me @nfotis, I did mean 2", I'm getting muddled about filter sizes!

Ian 

 

Um, 36mm filters are smaller (and cheaper) than the 2" filters (which are overkill for the IMX533)

N.F.

9 hours ago, turbo 2011 said:

I had seen this set up but it says ZWO only I did email firstlight optics they did send link to this but never mentioned that it would work on SX equipment? Might need to email them back.

Note that you should keep the total backfocus for Canon EF lenses to 44mm (flange to sensor distance), or you will have a real problem focusing.

N.F.

10 hours ago, The Admiral said:

Surely 2" filters would be adequate. That's what I use with my ASI533.

Ian

You mean 1.25" I suppose?

Yes, but I would want to use these with an IMX571 or similar sensor in the future, so 36mm filters would be a requirement for me.

N.F.

5 hours ago, SteveNickolls said:

Thanks for the 'heads up' on this product. Certainly keep it in mind if I aspire to a dual 533 rig.

Cheers,
Steve

I am tempted, as the price is quite competitive, but the cost of filters, filter wheel, etc makes me hesitate

(I calculated that a ZWO set of 36mm filters and filter wheel and an EAF will mean an expenditure of 1300+ dollars, before VAT and transport costs...)

That would mean a plunge into the monochrome world would set me back at least two thousand EUR...

N.F.

Now, SVBONY has entered the fray of monochrome cooled cameras with an IMX533 sensor (model: SV605MC )

https://www.svbony.com/svbony-sv605mc-mono-cooled-camera/

The Canon 6D has a much better sensor for modification, and this can be found quite cheap these days.

If the planets are quite low on the horizon, an ADC is VERY helpful in getting better planetary images.

A sensor like the IMX462 or IMX662 are quite nice for such a task, IMHO.

N.F.

If you still want to replace the old Trius with a modern sensor, I would suggest the IMX533 (available both in color and B&W models, cooled and non-cooled versions, from many manufacturers)

The IMX294 seems to be relatively fickle sensor, while the latest group (IMX533, IMX571 and IMX455?) offer lots of resolution and improvements.

The link below should give a comparison of the Trius to the IMX533:

https://astronomy.tools/calculators/field_of_view/?fov[]=3145||8677||1|1|0&fov[]=3145||35||1|1|0&messier=13

N.F.

Never trust a story teller, only actual users.

ChatGPT is *not* a search engine, it assembles persuasive text from a large amount of existing text.

N.F.

I have to say that the Skymax 180 is more pleasant to use, due to less weight and bulk.

I have noticed also that the C9.25 is painfully bright when using for visual observation with the Moon (and I get some floaters which make the visual observation rather unpleasant if I don't use a filter). On the other hand, the f/10 is nice for imaging, if you can do a careful collimation.

So, for visual observation I prefer the Skymax, for photography the C9.25

Hope this helps,

N.F.

3 hours ago, TrojanMan said:

Perhaps a silly question but I could use the same mount to do planetary observations and just throw a different scope on it right? I am guessing there are different requirements for cameras and filters. I am going to stick with DSO at first but would like to get a mount that can do both DSO and planetary.

Thanks!

As others say, a mount able to do DSO long exposures will easily do planetary imaging. Heck, I am using an unguided HEQ5 mount with my Skymax 180 for visual and planetary imaging...

By the way, you may want to buy used? I own a cheapo ED doublet 102/7 from SVBONY, which is quite nice (of course, a triplet is even nicer).

N.F.

9 hours ago, bluesilver said:

Ideally, if there was a APS-C sensor with the same pixel size as the asi2400, then that would be spot on ideal,  but yet to find one.

 

If you already have the ASI2400, you can just crop to APS-C size using the "region of interest" (ROI) function and keep the good parts of the photos (and the lower size of the shots is a bonus when trying to store/stack the frames)

N.F.

Hello there, and welcome.

DSO objects have very different requirements from planetary imaging/observation.

For DSO, a refractor around 80-100mm aperture is the most accommodating optical instrument. A doublet with ED glass is the minimum, a triplet is quite better in color correction (but more heavy and expensive). Focal distances (without flattener/reducer) are around 500-700mm (less if you use a reducer/flattener).

For planetary imaging, you don't even need a guiding scope, most are shooting fast video sequences over a minute or so (typically around 3-4 thousand frames), then stack the best 30% of frames or so. A large aperture and long focal distance are useful, catadioptric scopes of the Cassegrain family have an advantage (like Schmidt-Cassegrain such as the Celestron C8 or Maksutov-Cassegrain like the Skymax 150-180). These work best with small sensors when hunting planets.

You may want to check your field of view with various cameras/scope combination, to get an idea of what framing you can expect with various target, try this link:

https://astronomy.tools/calculators/field_of_view/

The EQ6-R mount is a popular selection and good value for money. The only bad thing is its weight. iOptron CEM mounts are lighter for the same payload, but pricier.

I don't know about your light pollution, but I suppose that you live in an urban area, so you may need to take it into consideration.

Hope this helps,

N.F.

It's hard to find a reducer suitable for full frame sensors in general (and you need to start from a quite large image circle).

If you start with a 44mm image circle, a reducer will reduce also this circle to a smaller size.

Better to shoot at native focal length instead, if you don't own an APS-C sensor. Else, you will have to crop out a big piece of the image I guess.

That said, there's a 3" reducer for large sensors which might do the job:

https://www.teleskop-express.de/shop/product_info.php/info/p6085_TS-Optics-REFRACTOR-0-79x-3--ED-Reducer-Corrector-for-big-sensors.html

N.F.

As others mentioned, the 80ED should be considered a complementary scope to a Maksutov, not an upgrade or downgrade.

The Maks are specialized instruments, these offer a long focal length and okay aperture at a compact package, and do it well. That makes these excellent planetary hunters, but these aren't the best for astrophotography (with a focal length of 2700+ mm, the Skymax 180 would be quite problematic on a mount smaller than an EQ6-R class at least).

For planetary imaging, I don't even guide on my HEQ5, I just shoot a minute of video (but manually focusing is a bit problematic, a remote focuser is a great help - vibration at such long focal lengths is a real problem).

N.F.

Hard to say which part improved what, unfortunately.

It's not easy to attribute a particular improvement when you change more than one parameter during testing.

N.F.

The Skymax 150 and 180 are excellent planet scopes (I love my 180).

Note that dew is often a problem in cold nights, and you have to bring these scopes outdoors at least one hour before you mount these

(what mount do you have? A HEQ5 class mount is very nice for the 150, just adequate for the 180).

N.F.

I think that the easiest way to get a large sensor (APS-C size) is to get a mirrorless used camera, like the Canon M-series (eg., M3), with 18mm flange distance or Sony E-mount 6xxx series (18mm). Especially the Canon M-series could use your Canon EF lenses via an adapter.

A dedicated astro camera with a large sensor will be VERY pricey, as the cost goes up with the size of the sensor. Maybe a used CCD camera could be useful?

N.F.

In SCT terms, I suppose that the maximum realistic size would be a C11 for astrophotography, correct?

What would be the suggested load factor for long exposure DSOs? Approximately 50% to 60%, I guess?

N.F.

It seems that the first announcements of this mount date back to spring 2019.

It sure took a long time to gestate, let's hope that the pandemic-induced delay will lead a well-engineered mount.

N.F.

Quite intriguing.

The head weight is almost the same as the EQ6-R, but with quite higher payload.

It's a direct competitor for the iOptron CEM70, for sure. Everyone will start making notes and comparisons between them.

The implementation details will make or break this mount. As it's the first Skywatcher mount using this design, I wouldn't expect them to have it perfected at first try (it will be a pleasant surprise if it performs well and reliably)

N.F.

On 04/12/2022 at 11:43, wornish said:

Looks like a serious piece of kit. But, at 33lbs (15KG) the head is just not practical for nightly setup and take down.

If I ever get a permanent site then I would be very tempted.

The EQ6-R head has the same weight, so it's not that bad.

It took them a long time to fruition. Probably the pandemic didn't help either?

N.F.

On 05/12/2022 at 21:02, The Lazy Astronomer said:

I've got the flimsy Nexstar mount the C6 came with, and the eq6r does DSO duties. I'm reluctant to be swapping scopes on the eq6r constantly (plus I'd then have to pick between DSO and planetary on a clear night). I wonder how much weight the little nexstar mount would take... 🤔

According to Celestron, the mount can handle up to approximately 5.5 kg or 12 lbs:

https://www.celestron.com/products/nexstar-6se-computerized-telescope#specifications

Note that you will have to include a Barlow and the camera at least into the mass budget.

For visual and planetary imaging, you can load the mount almost to the maximum stated limit, since you don't need accurate guiding (heck, I don't even guide on my HEQ5 when doing this). Obviously, the EQ6-R is a much better platform for this, but if you don't want to mess with it, you can try your C6 and a barlow on the Nexstar mount, if there's enough room for a straight connection  - else, you have to use a prism.

N.F.

1 hour ago, The Lazy Astronomer said:

Thanks for the input everyone! My current planetary scope is a lowly 6" SCT. Hopefully will be able to get something larger for next year, so will take a look at camera options to find something to fit both.

On a related note: is an ADC considered a necessity, or a nice-to-have?

If your planetary targets are low on the horizon, I would think that's very necessary (especially if you use optical glass elements in your chain - I think that a mirror-only scope like the Classical Cassegrain doesn't suffer from color fringing)

What mount do you have?

If you have an EQ6-R class mount, you can mount up to a C11 for planetary imaging/visual (heck, I even used a C9.25 on my HEQ5). My favourite is the Skymax 180, but that's especially suited for planetary and double stars - it's rather specialized.

Cheers,

N.F.

On 03/12/2022 at 02:01, The Lazy Astronomer said:

It seems like we're in a HGTTG situation here - perhaps I need to start a thread on the right question to ask first 😁

I'll try again: what are people's thoughts on which is the best planetary cam to buy these days? I think the 462mc was generally regarded as a good option previously, but are there any new thoughts on that given the new cameras that have been released in the past few months? 

Find a way out of that, @vlaiv 🤣

If you want to shoot Moon mosaics, you may want a larger sensor like the 662 or the 585.

The 462mc is still fine if you want to go after Jupiter and Saturn etc, but I have seen amazing results with the 533 too.

What scope and Barlow combination do you have in mind for this task?

Cheers,

N.F.