Deep sky camera advice

[Hedlund]

Hello

Im looking for advice for a affordable price camera for my telescope, Skywatcher 150pds. 

For planets observing and deep sky pictures. 

I have been looking at a Zwo ASI662MC, is this camera good for multipurpose use? Or should i looking at a dslr camera instead. 

Thanks in advance. 

[Adam J]

19 hours ago, Hedlund said:

Hello

Im looking for advice for a affordable price camera for my telescope, Skywatcher 150pds. 

For planets observing and deep sky pictures. 

I have been looking at a Zwo ASI662MC, is this camera good for multipurpose use? Or should i looking at a dslr camera instead. 

Thanks in advance. 

Honestly that's a very small sensor. I would not consider it good for general use. 

[happy-kat]

What sort of budget were you thinking of

[Hedlund]

5 hours ago, Adam J said:

Honestly that's a very small sensor. I would not consider it good for general use. 

Okey, thanks for your reply. 

Can you recommend any camera. 

[Hedlund]

4 hours ago, happy-kat said:

What sort of budget were you thinking of

Around 500-600$ if its possible

[happy-kat]

Whilst you are considering a camera you might find this an interesting thread on one of the new camera models

https://stargazerslounge.com/topic/397896-zwoplayer-one-imx-585-sensor-image-showcase/page/1

There is also the imaging resource FOV calculator to see what different cameras and your telescope will give, could compare a DSLR to different astro cameras.

Do you have a tracking mount for your telescope.

 

[Adam J]

17 hours ago, Hedlund said:

Okey, thanks for your reply. 

Can you recommend any camera. 

For that price the 585 is probably the way to go. But it is always worth looking for used dedicated cameras with larger sensors such as the 183 or the 533. 

Adam

[MichaelBibby]

On 07/10/2022 at 06:18, Hedlund said:

Around 500-600$ if its possible

The 585 is very well suited to your 750mm focal length (pixel size 2.9um). The 533 would also be a great option (I think the pixel size is about 3.88um, and a larger sensor than the 585), and ZWO are about to release an uncooled version which might just be within your price range.

Note: I don't have any experience with astrophotography, I've just been looking into similarly priced camera's, but for 1000mm focal length. I opted for the 585 because it seems well suited to my use case, which is video astronomy/EAA/EEVA.

[paulyz]

I have heritage 150p (identical parameters like Skywatcher 150pds) and looking for camera too.  Zwo cameras expensive, but if add canon 450d? I can get used for 50-100 eur, it will be ok for planets and DSO? Maybe canon better choice than cheap svbony or zwo models ? 

[happy-kat]

@paulyz you might find this interesting on canon cameras

https://www.astropix.com/html/equipment/canon_one_to_one_pixel_resolution.html

Perhaps look at example images to see whether for you a planetary camera or DSLR would work better out of what you are looking at. ZWO cameras with usb3 connector have the potential to connect to mobile devices using the ZWO asicap application for capturing (plus OTG cable) if you don't have a laptop or pc to connect to.

[paulyz]

@happy-kat  thanks, looks 450d beginner cheap choice. I'll not photographer and I don't think I'll astrophotographer,  we just explore sky with kids. We have 5mm eyepiece which good for planetary, but we don't see  acceptable DSO, we find m31, m11 and etc, but they just white dots. We checked youtube, how peoples at live look into DSO through cameras and after some correction get  DSO object with 6" telescope. So looking camera  to play, to make some photos.  And do not invest a lot. Looked for Logitech  C270 too, but canon looks more suitable for DSO.

Edited October 15, 2022 by paulyz

[KevinPSJ]

I have a 150p and a canon 600D which has given me some pleasing results. Have a look at my galleries - DSO and planetary. I am particularly pleased with how the 5x live view that means I can give pretty large images of Jupiter at least. I combine with a X2 Barlow but maybe x3 or x4 would be better for mars and Saturn. Not every canon can do the 5x live view with 1:1 pixel mapping - according to what I've read that is essential: https://www.astropix.com/html/equipment/canon_one_to_one_pixel_resolution.html

Having said all that, In my view the key thing to consider is weight - what mount do you have? I'm using the skywatcher eq3-2. If I recall correctly it's got a max payload spec around 5kg and with the tube and the camera I'm right at the limit of capability of this mount. I can manage subs of 30s reliably but that's it. 

[paulyz]

@KevinPSJ AZ stars dicovery wifi, which can carry 5 kg, heritage 150 ota max 4kg, so plus 0.5 kg for camera should be enought

[happy-kat]

That mount will be very helpful with the goto and tracking. Although the mount is AZ you can image but within the capabilities AZ gives as it tracks in tiny left right up down movements and not equatorial so the exposure lengths can't be too long, though this will very depending where you are pointing in the sky East and West in northern hemisphere between 20-50 odd is good. 

If you are sharing have you looked at live stacking? This builds an image live from what the camera is looking at. What I don't know is if you can use live stacking with a canon camera. Possible things to research here is ascom, sharpcap and astap. The first for the camera driver the latter two live stacking options.

**But** lastly I've just remembered the star discovery 150P telescope does not have enough inward focus travel to reach infinity focus with a mirrored DSLR. It may if a barlow is also used but you will have to search here and see what other people with the same setup have or have not managed.

[KevinPSJ]

@paulyz and @happy-kat. Good point about the focus. I have also heard that other variations of 150P have issues. I have the skywatcher Explorer 150P and have used both Nikon D3200 and Canon 600D at prime focus without problems with focus.

> AZ stars dicovery wifi, which can carry 5 kg

I've heard (can't recall where) that ideally you should aim for payloads around 50% of max load. Obviously I 'm exceeding that with my setup and it's probably limiting me. But maybe you could avoid this ....

Not sure how far your budget will stretch but you could look at a widefield camera lens combined with imaging camera rather than the using the skywatcher - second hand fixed focal length?

[paulyz]

@happy-kati know that az mount isn't ideal for astrophotography, but like I mentioned, I not planing go to pro level.

Heritage 150 can change focal length and I found in internet, that you can focus dslr changing focal length 

I saw that live pictures edited with sharpcap and if I understand good (googled) canon eos series can work in live session. 

[happy-kat]

If it is the heritage 150p telescope then if it's like my heritage 130p then it's about 1 inch the trusses need to be lowered for a camera to reach focus 

[paulyz]

@KevinPSJsw specifications 5kg, Orion (actually I don't remember good) gives 6kg to the same mount. That's because I bought discovery mount, GTI mount was only 50 euros expensive, but discovery looks for me more durable.  I put Celestron 5mm x-cel eyepiece which weight about 200 grams - mount work without problems. 

[paulyz]

5 minutes ago, happy-kat said:

If it is the heritage 150p telescope then if it's like my heritage 130p then it's about 1 inch the trusses need to be lowered for a camera to reach focus 

That means that dslr should work good.?

[davies07]

Hi,

I'm very late to this discussion (as usual), but I thought to add my two cents worth.

I've used a Canon 450D DSLR for a couple of years, and it produced some nice pictures but only after a lot of data gathering on an EQ mount. Uncooled DSLRs are noisy and require at least 55mm of back focus. I could not get mine to focus on a standard SW 200P scope (many years ago) and ended up replacing the focuser with a shallower version which enabled me to focus the camera but was horrible to use in other aspects.

I would wholeheartedly recommend a modern CMOS camera and a cooled one if you can afford it. The ASI 662 mentioned at the beginning of this thread would be a good choice, I think. The pixel count matches the resolution of modern monitors, making the camera ideal for live viewing (EAA). The only issue is that the pixels are rather small at 2.9um. For deep sky viewing with a scope around 750mm to 1000mm focal length, I would go for a camera with pixels in the 4um - 5um range. The ASI 482, for example, is 1920 x 1080 pixels at 5.8um and would be ideal for deep sky EAA. 

One of the advantages of a purpose-built astronomy camera is that the sensor is at the front of the device, giving a much shorter back focus requirement.

A modern CMOS camera has a variable gain enabling you to turn up the sensitivity to view fainter objects at the expense of saturating the brighter stars, losing their colour.

I don't understand the need to go for cameras with large sensors and high pixel counts unless you want to explore wide field-of-view images such as large nebulae. Most images are viewed on monitors, and most cameras will produce images that match their size and are suitable for exploring the vast majority of deep sky objects, which are rather small. The important aspect is getting the right image scale of around one arc sec per pixel, essentially the field of view of a single pixel.

I would recommend Sharpcap as your software. It works very well with modern cameras, and its live stacking feature is remarkable. Even on an Alt-Az mount, it is possible to take a sequence of very short exposures and let Sharpcap align and stack them. After a few minutes, the object will magically appear on the screen, with the background noise correspondingly reducing.

Good luck.

David

 

[paulyz]

@davies07thanks for reply. Yesterday I got Canon 500D for 100 euros, tomorrow will print T-mount adapter and if sky clear - night show

 

 

[paulyz]

New and I think very useful video about old DSLR these days 

 

 

My setup ready, printed T mount, mounted camera on telescope, focused (big advantage of Heritage 150p that I can focus just sliding tube), connected to pc  did test shots and video. Sky cloudy (100% coverage ) all weekend so taked test photos of city. Result good, need to wait clear sky. 

[paulyz]

finally I did photo session (very  sad situation with sky in my country), so what can do NOOB with DSLR (Canon D500) in 2022?

For me result good, now I can see spiral around center (through eyepiece visible only small dot). This photo taken near center of city, so big light pollution.

Now need to read more information about astrophotography and SharpCap and  practice, practice and again practice.

[imakebeer]

Hi All,

I've read through this thread with interest - I wonder if any of you can explain to a newbie what is mean by back focus, and the scope having/not having enough back focus and why it's important? (Or point me to a resource that explains it!)

Reason for asking - I've been having a go at planetary imaging with a basic setup (here's one example), and will have a bash at deep sky if it ever stops raining 😂.

I'm currently using a SkyWatcher 900mm/70mm refractor, now with a Canon EOS 450D (was using my Nikon D5500 initially), plus an Svbony eyepiece projection adapter.

But, I'm looking at upgrading to a SkyWatcher Explorer 150PDS - now as I understand it the PDS differs from the regular P by having a tweaked design to make it better for photography (or prime focus at least).....

I have a feeling this might be related to the back focus that has been mentioned. And I have a feeling it something to do with where the light is focused to a point, and where this point sits relative to the sensor in the camera, but I haven't quite had the Eureka moment yet. (and also I suppose barlow and/or eyepieces will also change the position of this point if they're used)

Can anyone help explain it?

[happy-kat]

Yes that's it, unless eyepieces are parfocal you often need to adjust focus when changing them.

With a reflector designed for visual observation when a camera DSLR is used instead of an eyepiece there is not always enough focus travel distance available for the DSLR to reach focus (often the DSLR chip in inset in the body 44mm for a mirrored Canon) , focus travel runs out of inward movement. Outward focus movement can always be accommodated for by extension tubes where needed. Backfocus becomes a critical distance when a comma corrector or field flattener is used as these with the imaging device have critical placement range.

The PDS reflectors are designed for being usable with a DSLR as well as an eyepiece and has a shorter tube (effectively moving the mirror higher when compared to the P of same length/aperture) (amongst other changes). If an eyepiece is used conversely an extension tube 2 inch long might be used in the focuser before the eyepiece to reach focus.

With a refractor when observing a diagonal is used, if instead a camera is used then the diagonal is often swapped for a 2 inch long extension tube then the camera in order to reach focus.

Edited November 7, 2022 by happy-kat