Thoughts on Canon Ra?

[pie_in_the_sky]

Hi all,

I know these types of questions are quite subjective and can be pointless as there is no right or wrong just personal preferences but...

What are your thoughts on the Canon Ra? I'm someway off upgrading my gear but am still interested to see what's out there. I see the value of a dedicated Astro-only camera (like the ZWO-type cameras) but I like the interactive element of a DSLR/Mirrorless and also would ideally like the dual purpose of an astro camera and a daytime camera which in theory the Ra would give you. I know some post prod is needed though when using the Ra in the day time.

How does the Ra stack up against the older 60Da?

I see lots of people raving about the Ra but the cynic in me suspects they are paid promotions.

I also see Astronomik making their incredibly subtle point: Please note that Canons Astro-Version "Ra" of the R-body shows strong halos around brighter stars! (Even without any filter) We highly recommend NOT to get a Ra! (https://www.astronomik.com/en/clip-filter/clip-filter-fur-canon-eos-r-eos-rp.html).

From what I understand Astronomik are fairly well regarded in the community so this likely carries a lot of weight...

As the forum says here https://www.dpreview.com/forums/thread/4522351, Astronomik likely wrote that before they knew there was a fix. Regardless, it seems bonkers to me that a £2.5k camera needs a ~£200 filter (assuming I'm looking at the right one) to make it work for its intended purpose. I'd understand daytime photography needing some extra effort, it being an astro camera first, but not for its primary purpose.

I realise I may have essentially answered my own questions - curious though to hear your thoughts.

Couple of technical bonus questions:

• Is the Ra considered a stock or modded camera?
• My understanding is that a Ha filter is redundant on the Ra. Is that correct?

Cheers

[wongataa]

I would say the Canon Ra is a stock camera as the different IR filter is a feature of the camera.  It is sold by Canon as having that different IR filter.  It is just a different type of stock camera than say a Canon non a camera.

Yes a Ha filter is redundant on a Ra.  By Ha filter I am assuming you mean a filter that only lets through the Ha wavelengths.  They really are redundant on all colour cameras as even if the camera doesn't have a IR filter blocking the Ra signal (I think all regular digital cameras will pick up Ra signals as their IR filters don't block it all) then only the red photosites will pick up Ra signal.  Only a quarter of the photosites are red so you would lose a lot of resolution and sensitivity.  For a single bandpass filter a mono camera is better as all the photosites will receive the filtered signal.

[Elp]

The filter thing isn't technically true. A narrowband osc like an lextreme helps separate background sky and emission. My a7s is blind to ha as it's factory, but when I used an lextreme on it the emission was there clearly and much better than imaging without.

The RA is an overpriced camera for what it is. Much better to get a standard modded body, or an astro camera will be far better due to better quantum efficiency and cleaner noise profile, especially if it's a cooled one (you can use uncooled ones for DSO I do it all the time and they're comparable to cooled).

[Icesheet]

It is a stock camera but the use of an additional Ha filter is not redundant. In fact in some scenarios it will be highly recommended. Although the Ra is more sensitive to the Ha spectrum than a normal EOS R it still benefits from a filter with a narrow band pass to really bring out those Ha emissions. 
 

It sounds like you are more tended towards DSO photography and in that case for the price of an EOS Ra you could have a very good dedicated astro camera and a decent stock mirrorless for daytime photography. 
 

For me an Ra or modded camera really come into their own when you are primarily shooting astro landscapes and might only shoot DSO stuff now and again. Bear in mind many telescopes don’t  support full frame. 
 

There is no doubt that an EOS Ra can be your only astro camera. Check out a guy called Mark Shelley but if you want it do it all it’s not worth the compromise in my opinion. I have a modded EOS R btw. Use it exclusively for astro landscapes. 

Edited January 31 by Icesheet
benefits rather than requires

[geeklee]

4 hours ago, pie_in_the_sky said:

My understanding is that a Ha filter is redundant on the Ra. Is that correct?

All an Ha filter (or multi band filter) will do is block other wavelengths of light getting through.  Without it, the Ra still lets more-than-typical-DSLR Ha through but it will be alongside the rest of the broadband spectrum.  It won't be redundant, but could be useful if you want to bring out the Ha emissions.

1 hour ago, Elp said:

My a7s is blind to ha as it's factory, but when I used an lextreme on it the emission was there clearly and much better than imaging without.

It won't be blind or you'd get nothing all the time.  It presumably has an early cut off on red in the builtin filter or only passes a little amount at that wavelength (like most DSLRs?).  When you put an L-eXtreme on it, you block the rest of the usual spectrum and therefore the Ha looks "better".  It's still the same amount of Ha getting through.

Edited January 31 by geeklee

[Elp]

Okay, maybe not blind but a less than 20pc pixel response in ha compared to say 80pc with my 533 astro camera, it's no where near as good.

[Adam J]

5 minutes ago, Elp said:

Okay, maybe not blind but a less than 20pc pixel response in ha compared to say 80pc with my 533 astro camera, it's no where near as good.

533 mono is not 80% in Ha, its more like 60% according to this chart. 

Now the IMX492 is about the best for Ha response at the moment and that really is about 80%, ASI1600mm pro is about 50%

Adam

 

Edited January 31 by Adam J

[Elp]

I looked at this as ZWOs page doesn't show one, the 183 shows around 80pc too which the 533 camera is often compared to:

https://www.firstlightoptics.com/zwo-cameras/zwo-asi-533mc-pro-usb-30-cooled-colour-camera.html

Often, the marketing blurb is questionable so take it with a pinch of salt. Also this is not factoring in the optics which will have a massive bearing on the per sub exposure.

Edited January 31 by Elp

[Adam J]

3 hours ago, Elp said:

I looked at this as ZWOs page doesn't show one, the 183 shows around 80pc too which the 533 camera is often compared to:

https://www.firstlightoptics.com/zwo-cameras/zwo-asi-533mc-pro-usb-30-cooled-colour-camera.html

Often, the marketing blurb is questionable so take it with a pinch of salt. Also this is not factoring in the optics which will have a massive bearing on the per sub exposure.

That link gives a relative response as opposed to a absolute response. 

[pie_in_the_sky]

On 31/01/2024 at 13:33, Elp said:

The RA is an overpriced camera for what it is. Much better to get a standard modded body, or an astro camera will be far better due to better quantum efficiency and cleaner noise profile, especially if it's a cooled one (you can use uncooled ones for DSO I do it all the time and they're comparable to cooled).

It's a good point - new I could buy a colour and a mono...although I have been offered a Ra for £1500 (photographer I knew bought one on a whim and doesn't like it...). Still though, it's a lot of money at this stage.

For a Canon crop sensor, what would you say is a decent option for a modden DSLR? Quick follow up - from what I've read crop sensors seem to be preferred to full-frame. Is that the case?

On 31/01/2024 at 15:25, Icesheet said:

It is a stock camera but the use of an additional Ha filter is not redundant. In fact in some scenarios it will be highly recommended. Although the Ra is more sensitive to the Ha spectrum than a normal EOS R it still benefits from a filter with a narrow band pass to really bring out those Ha emissions. 
 

It sounds like you are more tended towards DSO photography and in that case for the price of an EOS Ra you could have a very good dedicated astro camera and a decent stock mirrorless for daytime photography. 
 

For me an Ra or modded camera really come into their own when you are primarily shooting astro landscapes and might only shoot DSO stuff now and again. Bear in mind many telescopes don’t  support full frame. 
 

There is no doubt that an EOS Ra can be your only astro camera. Check out a guy called Mark Shelley but if you want it do it all it’s not worth the compromise in my opinion. I have a modded EOS R btw. Use it exclusively for astro landscapes. 

Cheers - yep, looking into it some more I could get a couple of ZWOs for the same price new! That's a good point though about a dedicated astro and a stock camera for daytime. You're right about the DSO - it's probably going to be mainly DSO with occasional landscapes.

It sounds like you're all in on the mirrorless. What took you away from DSLR? Out of interest, what DSLR (modded) would you say is a good option?

Last one, can you expand on the point about scopes not supporting full frame - is this because it results in vignetting or is there something else?

On 31/01/2024 at 15:27, geeklee said:

All an Ha filter (or multi band filter) will do is block other wavelengths of light getting through.  Without it, the Ra still lets more-than-typical-DSLR Ha through but it will be alongside the rest of the broadband spectrum.  It won't be redundant, but could be useful if you want to bring out the Ha emissions.

I've probably been thinking about filters wrong. Rather than saying they 'boost' one thing over another, is it more accurate to say they block everything else and leave whatever your target is. I.e. a Ha filter doesn't boost Ha, rather it leaves that behind after filtering out other frequencies? That might be a bit rambling but am I on the right track?

[Elp]

51 minutes ago, pie_in_the_sky said:

For a Canon crop sensor, what would you say is a decent option for a modden DSLR? Quick follow up - from what I've read crop sensors seem to be preferred to full-frame. Is that the case?

Not so sure now, I used to have a modded Canon 600D which was okay though the noise it left even in calibrated images was nowhere near the quality of an astro camera. The modification however did improve it's HA response, seeing the horsehead peek through the dark on a single 120s exposure was something I'll remember. At the time I was also looking at Nikon D750/810/850 for upgrading to full frame. I decided to change to Sony FF but I wouldn't recommend these for AP as their sensors do strange things (not normal linear digital response which affects flats calibration, split sensor construction, star eater noise reduction algorithm, I can only speak for the model I have but the issues are well documented online). I generally use my camera lenses with astro cameras nowadays, it's not really difficult to adapt them as long as theyre manual primes, some AF ones may have aperture locks on them but usually you need a camera body to lock the apertures in place if it can be done in the first place, and utilise an asiair to control the image acquisition. Once youve done it, it's fairly straightforward to setup in future, you get the benefit of plate solving and starfield annotation so you know where youre pointing and if the air is connected to the mount it can also control where the mount is pointing. Some DSLR and mirrorless bodies are also supported with the Asiair but if youre using an astro camera is has to be a ZWO model. Alternative computer controllers include Raspberry Pis loaded with Astroberry or Stellarmate, or using a laptop with NINA or equivalent. For astro, unless I'm imaging widefield say less than 24mm, I prefer using automation, makes it so much more hassle free.

Full frame is fine, but AP performance varies from model to model. Obviously if you intend to use them with a telescope in the future you'd have to check if the telescope can illuminate a full frame imaging circle. You don't necessarily need a modern body, I still have fun with my compacts and mobile phones which can image in RAW.

Edited February 1 by Elp

[geeklee]

3 hours ago, pie_in_the_sky said:

That might be a bit rambling but am I on the right track?

Yeah, exactly.  You see some labelled "boost" or "booster" but they're not getting more of a particular signal through, just blocking more of the stuff that can get in the way.

3 hours ago, pie_in_the_sky said:

from what I've read crop sensors seem to be preferred to full-frame. Is that the case?

Full frame can be challenging for some (most?) optics.  This may be sensor illumination and/or star quality (although some modern tools can help with the latter)

[Icesheet]

On 01/02/2024 at 18:00, pie_in_the_sky said:

Cheers - yep, looking into it some more I could get a couple of ZWOs for the same price new! That's a good point though about a dedicated astro and a stock camera for daytime. You're right about the DSO - it's probably going to be mainly DSO with occasional landscapes.

It sounds like you're all in on the mirrorless. What took you away from DSLR? Out of interest, what DSLR (modded) would you say is a good option?

Last one, can you expand on the point about scopes not supporting full frame - is this because it results in vignetting or is there something else?

I didn't specifically move because it was mirrorless, just that a modded EOS R came on the market. Before that I had a modded 6D and that is generally a well thought of DSLR for astrophotography. If you say it's mainly DSO stuff you're interested in then I would encourage you to get a dedicated cooled astrocamera instead. I've only used a modded 6D and EOS R, which I've been happy with. Really couldn't say if they are any better or worse than others.

 

@geeklee covered it regarding scopes not covering full frame. It's just something to bear in mind so you don't shell out on a very expensive full frame sensor only to find out you can't make use of it.

[Shimrod]

On 31/01/2024 at 10:51, pie_in_the_sky said:

Hi all,

I know these types of questions are quite subjective and can be pointless as there is no right or wrong just personal preferences but...

What are your thoughts on the Canon Ra? I'm someway off upgrading my gear but am still interested to see what's out there. I see the value of a dedicated Astro-only camera (like the ZWO-type cameras) but I like the interactive element of a DSLR/Mirrorless and also would ideally like the dual purpose of an astro camera and a daytime camera which in theory the Ra would give you. I know some post prod is needed though when using the Ra in the day time.

 

I think your biggest challenge will be finding a Canon Ra at a sensible price - it was launched in 2019 and discontinued by 2021. I don't think they sold a huge amount, and a quick search reveals only two on ebay - one with a starting bid of £1850 and the other with a price of £4000 (both body only). 

It's probably cheaper to buy a dedicated astro camera and the R6 full frame body and you will have the reassurance of a warranty on both.

[pie_in_the_sky]

Thanks for the info - very helpful and will keep it in mind when I come to upgrade.