Recommendations for telescope

[Mystiqz]

Hi all,

I am new to this hobby and was wondering If anybody could recommend me a few telescopes for astrophotography?  I would greatly appreciate it. I am looking for one that is compatible with canon R5, cost <$5K, and will not be doing long hour exposures (but having the feature/ability to do so would be a nice perk).  Thanks in advance.

[discardedastro]

The most important thing to answer this question is what do you want to take photos of?

Deep space objects will require tracking, and moderate FLs, and will normally involve long exposures. Planetary requires plenty of aperture and long focal lengths. These are frequently incompatible so you're looking at different scopes for each in all likelihood!

You can do a lot of AP without a telescope at all, just a tracking platform for your existing camera and lenses (the R5 isn't ideal for AP compared to the R6 owing to smaller pixel size, but is still a superb camera for it). This can be ideal for wide field.

If you're not sure then I'd start with widefield as you can do this quite affordably and see if you like the hobby while buying minimal specialist kit - you might end up with a decent fast lens, a platform, dew heater and so on. What's your background with observing?

[iapa]

You don’t say if you have anything at the moment.

if you don’t, this is a Lot of money to be spending on your first setup.

do you plan to take images of the planets, galaxies, etc.

[vlaiv]

Hi and welcome to SGL.

What mount will you be using and what are your intended targets. In case you are looking to start with astrophotograpy - then first think of the mount that is suitable - scope comes almost last.

[Mystiqz]

thank you all for the input.

i'm most certain that i won't be doing deep space objects so i'll definitely try for a tracking platform and just my camera and see. I already have a lot of canon lenses so I'll try those out and see how I want to proceed further with the hobby.

 

 

[iapa]

Skywatcher make  two Star Adventurer models. Look for the Pro versions as these include bits and bobs such are counterweights and such.

there are also products from IOptron and Astrotec as well as Vixen

i think I’ve seen a comparison on utoob somewhere.

[Mystiqz]

1 hour ago, discardedastro said:

The most important thing to answer this question is what do you want to take photos of?

Deep space objects will require tracking, and moderate FLs, and will normally involve long exposures. Planetary requires plenty of aperture and long focal lengths. These are frequently incompatible so you're looking at different scopes for each in all likelihood!

You can do a lot of AP without a telescope at all, just a tracking platform for your existing camera and lenses (the R5 isn't ideal for AP compared to the R6 owing to smaller pixel size, but is still a superb camera for it). This can be ideal for wide field.

If you're not sure then I'd start with widefield as you can do this quite affordably and see if you like the hobby while buying minimal specialist kit - you might end up with a decent fast lens, a platform, dew heater and so on. What's your background with observing?

sorry but what do you mean by FL?

[discardedastro]

That's a good starting point for sure. Something like the iOptron SkyGuiders (iPolar is nice to simplify setup) are worth looking at for a decent tracker, or the Star Adventurer from Skywatcher. Basically this lot: https://www.firstlightoptics.com/star-tracker-astronomy-mounts.html

You may find a dew heater useful for your lenses if you're outside for any length of time - cheap and cheerful ones will do fine with a 12V supply from a power tank or any old 12V battery. Guessing you'll already have a good solid tripod but if not definitely worth getting one. A Bahtinov mask can be a really helpful and low-cost upgrade for focus accuracy, and a cheap flat field generator (try A4 sketching tablet lights on Amazon etc, perfectly good and cheap as chips) will be invaluable in doing proper calibration of your images which if you're using lenses with any vignetting will be well worth doing (and plenty of lenses have noticeable vignetting for long exposures - even a Zeiss Otus f/1.4 28mm benefited).

Software is a non-trivial expense depending on the route you go down, Photoshop etc will get you far but if you want to combine multiple images then there are plenty of free options like APP or commercial options like PixInsight.

[discardedastro]

Just now, Mystiqz said:

sorry but what do you mean by FL?

Focal length, i.e. the mm number on your lenses.

[vlaiv]

8 minutes ago, Mystiqz said:

thank you all for the input.

i'm most certain that i won't be doing deep space objects so i'll definitely try for a tracking platform and just my camera and see. I already have a lot of canon lenses so I'll try those out and see how I want to proceed further with the hobby.

 

 

Deep sky objects or DSOs how they are popularly abbreviated, are all the things that you can image that are beyond solar system.

If you use just camera and lens and simple star tracker - you will still be shooting DSOs. Don't let the name fool you - like these are sort of special objects that you need very expensive equipment to image.

There is basic distinction between solar system objects and DSOs in the way they are imaged. Most interesting solar system objects - planets and the Moon (and even Sun) - are imaged with so called lucky imaging technique. It requires special camera that shoots very fast sequence of frames (like hundreds of FPSs) and those images are stacked and processed in particular way. Exposures are extremely short - in milliseconds.

You don't need very good mount to be able to do that as tracking only needs to keep object in field of view.

On the other hand - DSO imaging requires longer exposures (anything longer than few seconds is considered longer exposure but in practice we are talking minutes rather than seconds), and here mount is very important. If you want to do this kind of photography - next thing to choose is your working resolution.

You can go for wide field shots that capture constellations and large diffuse nebulae - that means camera + lens or very small telescope. Working resolutions are above 4"/px and mount tracking is not essential.

Star trackers enable you to do this. Focal lengths are in 50-200mm range

Next step up is small telescope range. Here we are talking about 200-400mm FL range (although technically more in 4"-2"/px range). Mount becomes much more important here. Larger nebulae and galaxies fall in this category.

Again, step up is medium resolution and here we are talking about 2" - 1.5"/px. Mount is very important here. This is general working resolution - most things can be imaged at this resolution but some objects will be small.

Above 1.5"/px - we are talking about high resolution imaging and mount is the most important thing here. Sky quality is another important thing. You need stable atmosphere to image at say 1.2"/px

This is just small overview of things to get you started - it would be best if you tell us your goals and aspirations so we can give you proper advice.

 

[iapa]

27 minutes ago, Mystiqz said:

sorry but what do you mean by FL?

Focal length.

calculated from focal ratio (f) and the diameter (d) of the telescope.

fl = f x d

so, an F5 telescope with 80mm lens has a focal length of 400mm.

The longer the focal length, the narrower the field of view (the amount of sky you will see).

If you want to image andromeda galaxy (M31) which is quite a large one (wide) then the 400mm would be about right.

if you want, for example, the whirlpool galaxy (M51) - this is a bit of a misnomer as it is two interacting galaxies - then you will need a longer focal length as 900mm

remember that lens diameter is relative - the wider it is the more light you can get in any single period of time.

A 900mm telescope could be an f5 telescope with lens diameter of 180mm, or f2 and 450mm or 15” diameter lens.

As you can see, it becomes  important to know what you prefer to image.

There is an online tool you can use to determine what you can see with different telescope / camera combinations: http://astronomy.tools/calculators/field_of_view/

 

Edited April 8, 2021 by iapa

[iapa]

Further to @vlaiv ‘s reply.

”/px is arcseconds per pixel on your camera sensor

60 arcsecs in a degree of rotation.

http://astronomy.tools/calculators/field_of_view/ Also shows this value

[vlaiv]

39 minutes ago, iapa said:

60 arcsecs in a degree of rotation.

A bit more - 60 arc seconds per arc minute and 60 arc minutes per one degree.

[iapa]

27 minutes ago, vlaiv said:

A bit more - 60 arc seconds per arc minute and 60 arc minutes per one degree.

Thppppppt

[ScouseSpaceCadet]

If you already have a decent photography kit, maybe just stick with that and a suitable mount.

 

Edited April 8, 2021 by ScouseSpaceCadet

[AstroNebulee]

Plus 1 for a skywatcher star adventurer, also an apo refractor like skywatcher 72ed