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Budget Solar H-Alpha with a Canon R7 (or maybe a dedicated camera)

Equipment DSLR H-alpha Sun
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Jean-David Gadina avatar
Jean-David Gadina avatar
I’ve recently started to look for entry-level H-Alpha solar telescopes, and I would like to know if it’s possible to use them with a DSLR-type camera and still get decent results.

I’m using a Canon R7 (RF mount, but I also have an EF adapter).

I’m sure most of you will recommend getting a dedicated astrophotography camera.
While I might do that in the future, I’d like to stick with my Canon for now.

Ideally, I would like to attach the camera directly to the scope, although I might consider eyepiece projection if that's the only option.

So far, I've looked into these models:

Now, I believe I can rule out the Coronado PST, as I don't think it has been designed with a camera in mind.
I think the Daystar SS60-ds and the Lunt 50mm look more interesting.

Would any of these be compatible with my Canon R7, and if so, do you have any recommendations?

Also, what should I consider when imaging with a DSLR with such a scope? Will I run into issues with back focus?
Are there any other technical problems I'm overlooking?
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Jean-David Gadina avatar
Jean-David Gadina avatar
Well, the more I read, the more I think this is not a good idea.

I'm unsure I can achieve focus unless I use eyepiece projection, regardless of the scope.
Also, obviously, using a color sensor for H-Alpha will not produce good images.

So, I would also enjoy any recommendation for a not-too-expensive dedicated monochrome camera.

As for the scope, the Lunt 50mm looks more interesting since it can be upgraded.
Any thoughts on the ASI678MM (or ASI178MM) for that purpose?
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C.Sand avatar
C.Sand avatar
Hi, I'm not too experienced with solar but have been doing off and on research to get into it. For full disk I know the 178 is great, but I don't know too much about the 678 for solar specifically. It looks like it would do well but don't take my word for it. I know you also should "match" pixel size with F-ratio/focal length, so look for information on that.

Between the lunt 40 and 50 there isn't any massive gain to the 10mm of aperature. Of course the 50 will be a little better, but from what I understand going to the 60 is the most meaningful jump, as you get the improved focuser (and other improvements?). 

Daystar has quality control issues. Their quantum series is their best and (should be) perfect, but there are plenty of copies that are not. Their quark series are the rejects of the quantums. The scout are the rejects of the quarks. I've personally heard and experienced (with 2 quarks) enough negative that it has effectively turned me off daystar, so I would say be cautious at best. 


IMO go for a lunt 40 or 60, get a nice barlow (powermate?) and dedicated cam (174?).

Quick edit. The camera names are confusing. I don't remeber if the 174 is good or the 178. Disregard any camera advice I gave. The matching pixel size to fratio/focal length is the important thing.
Jean-David Gadina avatar
Jean-David Gadina avatar
Thanks a lot for this information @C.Sand !
The matching pixel size to fratio/focal length is the important thing.

So, as both the Lunt 50 and 60 are F/7, the ASI178 or ASI678 would be more suitable since they have a smaller pixel size (2 and 2.4).
The ASI174 (5.86) would be better suited for a setup with a Barlow.

The ASI678 should perform similarly to the ASI178, as it's an upgrade with slightly smaller pixels.

The Lunt 60mm is indeed interesting.
It is more expensive, but I like that it may also be used for non-solar imaging.
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Luka Poropat avatar
Luka Poropat avatar
Between the lunt 40 and 50 there isn't any massive gain to the 10mm of aperature. Of course the 50 will be a little better, but from what I understand going to the 60 is the most meaningful jump, as you get the improved focuser (and other improvements?).


Going from 40mm to 50mm is already a big improvement, the 10mm is a difference you can easily see. Also the 50mm+ scopes all have pressure tuning instead of tilt tuning as its primary single stack etalon.

Ofcourse the bigger the better, however do keep in mind major improvement quality wise for the average user is a DS or double stacking module where you put another form of an etalon (either another primary tilt or pressure tuner) and boost the contrast of an image and remove the "double limb".

For Solar Ha the only way is MONO. Shooting mono RAW16 is such a massive improvement even to the best color sensor there is. 

If you were to buy a 40/50/60 you will probably only be shooting "full disc" images. So something like a IMX429 or IMX533 would work the best. 

Also for the double stacking, a DS 50mm will be better option than a single stack 60mm in my opinion.
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C.Sand avatar
C.Sand avatar
Luka Poropat:
Going from 40mm to 50mm is already a big improvement, the 10mm is a difference you can easily see. Also the 50mm+ scopes all have pressure tuning instead of tilt tuning as its primary single stack etalon.


I wasn't aware of the pressure/tilt tuning. Pressure better, go 50 (edit: or bigger) then.

Obviously yes the 10mm difference is impactful, just imo for the price increase not worth it. (again though, pressure tuning is worth it)
Jean-David Gadina avatar
Jean-David Gadina avatar
So, as a follow-up, I also received a response from Lunt confirming all that has been said previously.

Although they recommend a monochrome camera such as the ASI174, they also say that if I really want to go with a DSLR, the 40mm is the only option.
The 50mm won’t achieve focus with a DSLR.

Anyway, I decided to increase the budget and go with a Lunt 60mm universal telescope paired with an ASI678MM.

The rig is more expensive than I had initially planned, but I like that I will also be able to use the telescope for some deep sky targets, especially larger ones, since its short focal length.

I can't wait to try this out!
Thanks to everyone here for their recommendations!
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Oscar avatar
Oscar avatar
Jean-David Gadina:
The rig is more expensive than I had initially planned, but I like that I will also be able to use the telescope for some deep sky targets, especially larger ones, since its short focal length.


you might get some CA, because of the doublet design.

and you'll also need a flattener for it, if you're gonna use it for DSO photography.
Oscar avatar
Oscar avatar
Also, I'm not at all sure but, I think you also need a Lunt blocking filter? I heard that you really need one for visual solar use, but IDK about imaging use.

You probably don't, but make sure.